TY  - JOUR
A1  - Neugart, Susanne
A1  - Wiesner-Reinhold, Melanie
A1  - Frede, Katja
A1  - Jander, Elisabeth
A1  - Homann, Thomas
A1  - Rawel, Harshadrai Manilal
A1  - Schreiner, Monika
A1  - Baldermann, Susanne
T1  - Effect of Solid Biological Waste Compost on the Metabolite Profile of Brassica rapa ssp chinensis
JF  - Frontiers in plant science : FPLS
N2  - Large quantities of biological waste are generated at various steps within the food production chain and a great utilization potential for this solid biological waste exists apart from the current main usage for the feedstuff sector. It remains unclear how the usage of biological waste as compost modulates plant metabolites. We investigated the effect of biological waste of the processing of coffee, aronia, and hop added to soil on the plant metabolite profile by means of liquid chromatography in pak choi sprouts. Here we demonstrate that the solid biological waste composts induced specific changes in the metabolite profiles and the changes are depending on the type of the organic residues and its concentration in soil. The targeted analysis of selected plant metabolites, associated with health beneficial properties of the Brassicaceae family, revealed increased concentrations of carotenoids (up to 3.2-fold) and decreased amounts of glucosinolates (up to 4.7-fold) as well as phenolic compounds (up to 1.5-fold).
KW  - metabolite profiling
KW  - LC/MS
KW  - pak choi
KW  - carotenoids
KW  - phenolic compounds
KW  - glucosinolates
Y1  - 2018
U6  - https://doi.org/10.3389/fpls.2018.00305
SN  - 1664-462X
VL  - 9
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Jobe, Jessica Ann Thompson
A1  - Li, Tao
A1  - Bookhagen, Bodo
A1  - Chen, Jie
A1  - Burbank, Douglas W.
T1  - Dating growth strata and basin fill by combining Al-26/Be-10 burial dating and magnetostratigraphy
BT  - Constraining active deformation in the Pamir-Tian Shan convergence zone, NW China
JF  - Lithosphere
N2  - Cosmogenic burial dating enables dating of coarse-grained, Pliocene-Pleistocene sedimentary units that are typically difficult to date with traditional methods, such as magnetostratigraphy. In the actively deforming western Tarim Basin in NW China, Pliocene-Pleistocene conglomerates were dated at eight sites, integrating Al-26/Be-10 burial dating with previously published magnetostratigraphic sections. These samples were collected from growth strata on the flanks of growing folds and from sedimentary units beneath active faults to place timing constraints on the initiation of deformation of structures within the basin and on shortening rates on active faults. These new basin-fill and growthstrata ages document the late Neogene and Quaternary growth of the Pamir and Tian Shan orogens between >5 and 1 Ma and delineate the eastward propagation of deformation at rates up to 115 km/m.y. and basinward growth of both mountain belts at rates up to 12 km/m.y.
Y1  - 2018
U6  - https://doi.org/10.1130/L727.1
SN  - 1941-8264
SN  - 1947-4253
VL  - 10
IS  - 6
SP  - 806
EP  - 828
PB  - American Institute of Physics
CY  - Boulder
ER  - 
TY  - JOUR
A1  - Weng, Wei
A1  - Lüdeke, Matthias K. B.
A1  - Zemp, Delphine Clara
A1  - Lakes, Tobia
A1  - Kropp, Jürgen
T1  - Aerial and surface rivers
BT  - downwind impacts on water availability from land use changes in Amazonia
JF  - Hydrology and earth system sciences : HESS
N2  - The abundant evapotranspiration provided by the Amazon forests is an important component of the hydrological cycle, both regionally and globally. Since the last century, deforestation and expanding agricultural activities have been changing the ecosystem and its provision of moisture to the atmosphere. However, it remains uncertain how the ongoing land use change will influence rainfall, runoff, and water availability as findings from previous studies differ. Using moisture tracking experiments based on observational data, we provide a spatially detailed analysis recognizing potential teleconnection between source and sink regions of atmospheric moisture. We apply land use scenarios in upwind moisture sources and quantify the corresponding rainfall and runoff changes in downwind moisture sinks. We find spatially varying responses of water regimes to land use changes, which may explain the diverse results from previous studies. Parts of the Peruvian Amazon and western Bolivia are identified as the sink areas most sensitive to land use change in the Amazon and we highlight the current water stress by Amazonian land use change on these areas in terms of the water availability. Furthermore, we also identify the influential source areas where land use change may considerably reduce a given target sink's water reception (from our example of the Ucayali River basin outlet, rainfall by 5–12 % and runoff by 19–50 % according to scenarios). Sensitive sinks and influential sources are therefore suggested as hotspots for achieving sustainable land–water management.
Y1  - 2018
U6  - https://doi.org/10.5194/hess-22-911-2018
SN  - 1027-5606
SN  - 1607-7938
VL  - 22
IS  - 1
SP  - 911
EP  - 927
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Ritter, Christoph
A1  - Ángeles Burgos, María
A1  - Böckmann, Christine
A1  - Mateos, David
A1  - Lisok, Justyna
A1  - Markowicz, Krzysztof M.
A1  - Moroni, Beatrice
A1  - Cappelletti, David
A1  - Udisti, Roberto
A1  - Maturilli, Marion
A1  - Neuber, Roland
T1  - Microphysical properties and radiative impact of an intense biomass burning aerosol event measured over Ny-angstrom lesund, Spitsbergen in July 2015
JF  - Tellus - Series B, Chemical and Physical Meteorology
N2  - In this work, an evaluation of an intense biomass burning event observed over Ny-angstrom lesund (Spitsbergen, European Arctic) in July 2015 is presented. Data from the multi-wavelengths Raman-lidar KARL, a sun photometer and radiosonde measurements are used to derive some microphysical properties of the biomass burning aerosol as size distribution, refractive index and single scattering albedo at different relative humidities. Predominantly particles in the accumulation mode have been found with a bi-modal distribution and dominance of the smaller mode. Above 80% relative humidity, hygroscopic growth in terms of an increase of particle diameter and a slight decrease of the index of refraction (real and imaginary part) has been found. Values of the single scattering albedo around 0.9 both at 355nm and 532nm indicate some absorption by the aerosol. Values of the lidar ratio are around 26sr for 355nm and around 50sr for 532nm, almost independent of the relative humidity. Further, data from the photometer and surface radiation values from the local baseline surface radiation network (BSRN) have been applied to derive the radiative impact of the biomass burning event purely from observational data by comparison with a clear background day. We found a strong cooling for the visible radiation and a slight warming in the infra-red. The net aerosol forcing, derived by comparison with a clear background day purely from observational data, obtained a value of -95 W/m(2) per unit AOD500.
KW  - aerosol
KW  - lidar
KW  - retrieval of aerosol properties
KW  - radiative forcing
KW  - Arctic aerosol
Y1  - 2018
U6  - https://doi.org/10.1080/16000889.2018.1539618
SN  - 1600-0889
VL  - 70
PB  - Routledge, Taylor & Francis Group
CY  - Abingdon
ER  - 
TY  - JOUR
A1  - Metin, Ayse Duha
A1  - Nguyen Viet Dung, 
A1  - Schröter, Kai
A1  - Guse, Björn
A1  - Apel, Heiko
A1  - Kreibich, Heidi
A1  - Vorogushyn, Sergiy
A1  - Merz, Bruno
T1  - How do changes along the risk chain affect flood risk?
JF  - Natural hazards and earth system sciences
N2  - Flood risk is impacted by a range of physical and socio-economic processes. Hence, the quantification of flood risk ideally considers the complete flood risk chain, from atmospheric processes through catchment and river system processes to damage mechanisms in the affected areas. Although it is generally accepted that a multitude of changes along the risk chain can occur and impact flood risk, there is a lack of knowledge of how and to what extent changes in influencing factors propagate through the chain and finally affect flood risk. To fill this gap, we present a comprehensive sensitivity analysis which considers changes in all risk components, i.e. changes in climate, catchment, river system, land use, assets, and vulnerability. The application of this framework to the mesoscale Mulde catchment in Germany shows that flood risk can vary dramatically as a consequence of plausible change scenarios. It further reveals that components that have not received much attention, such as changes in dike systems or in vulnerability, may outweigh changes in often investigated components, such as climate. Although the specific results are conditional on the case study area and the selected assumptions, they emphasize the need for a broader consideration of potential drivers of change in a comprehensive way. Hence, our approach contributes to a better understanding of how the different risk components influence the overall flood risk.
Y1  - 2018
U6  - https://doi.org/10.5194/nhess-18-3089-2018
SN  - 1561-8633
SN  - 1684-9981
VL  - 18
IS  - 11
SP  - 3089
EP  - 3108
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Foster, William J.
A1  - Heindel, Katrin
A1  - Richoz, Sylvain
A1  - Gliwa, Jana
A1  - Lehrmann, Daniel J.
A1  - Baud, Aymon
A1  - Kolar-Jurkovsek, Tea
A1  - Aljinovic, Dunja
A1  - Jurkovsek, Bogdan
A1  - Korn, Dieter
A1  - Martindale, Rowan C.
A1  - Peckmann, Jörn
T1  - Suppressed competitive exclusion enabled the proliferation of Permian/Triassic boundary microbialites
JF  - The Depositional Record : the open access journal of the International Association of Sedimentologists
N2  - During the earliest Triassic microbial mats flourished in the photic zones of marginal seas, generating widespread microbialites. It has been suggested that anoxic conditions in shallow marine environments, linked to the end-Permian mass extinction, limited mat-inhibiting metazoans allowing for this microbialite expansion. The presence of a diverse suite of proxies indicating oxygenated shallow sea-water conditions (metazoan fossils, biomarkers and redox proxies) from microbialite successions have, however, challenged the inference of anoxic conditions. Here, the distribution and faunal composition of Griesbachian microbialites from China, Iran, Turkey, Armenia, Slovenia and Hungary are investigated to determine the factors that allowed microbialite-forming microbial mats to flourish following the end-Permian crisis. The results presented here show that Neotethyan microbial buildups record a unique faunal association due to the presence of keratose sponges, while the Palaeotethyan buildups have a higher proportion of molluscs and the foraminifera Earlandia. The distribution of the faunal components within the microbial fabrics suggests that, except for the keratose sponges and some microconchids, most of the metazoans were transported into the microbial framework via wave currents. The presence of both microbialites and metazoan associations were limited to oxygenated settings, suggesting that a factor other than anoxia resulted in a relaxation of ecological constraints following the mass extinction event. It is inferred that the end-Permian mass extinction event decreased the diversity and abundance of metazoans to the point of significantly reducing competition, allowing photosynthesis-based microbial mats to flourish in shallow water settings and resulting in the formation of widespread microbialites.
KW  - Competitive exclusion
KW  - Permian
KW  - Triassic
KW  - mass extinction
KW  - microbialites
KW  - palaeoecology
Y1  - 2019
U6  - https://doi.org/10.1002/dep2.97
SN  - 2055-4877
VL  - 6
IS  - 1
SP  - 62
EP  - 74
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Bielcik, Milos
A1  - Aguilar-Trigueros, Carlos A.
A1  - Lakovic, Milica
A1  - Jeltsch, Florian
A1  - Rillig, Matthias C.
T1  - The role of active movement in fungal ecology and community assembly
JF  - Movement Ecology
N2  - Movement ecology aims to provide common terminology and an integrative framework of movement research across all groups of organisms. Yet such work has focused on unitary organisms so far, and thus the important group of filamentous fungi has not been considered in this context. With the exception of spore dispersal, movement in filamentous fungi has not been integrated into the movement ecology field. At the same time, the field of fungal ecology has been advancing research on topics like informed growth, mycelial translocations, or fungal highways using its own terminology and frameworks, overlooking the theoretical developments within movement ecology. We provide a conceptual and terminological framework for interdisciplinary collaboration between these two disciplines, and show how both can benefit from closer links: We show how placing the knowledge from fungal biology and ecology into the framework of movement ecology can inspire both theoretical and empirical developments, eventually leading towards a better understanding of fungal ecology and community assembly. Conversely, by a greater focus on movement specificities of filamentous fungi, movement ecology stands to benefit from the challenge to evolve its concepts and terminology towards even greater universality. We show how our concept can be applied for other modular organisms (such as clonal plants and slime molds), and how this can lead towards comparative studies with the relationship between organismal movement and ecosystems in the focus.
KW  - Filamentous fungi
KW  - Microbial community
KW  - Active movement
KW  - Modular organisms
KW  - Interference competition
KW  - Fungal space searching algorithms
KW  - Fungal foraging
KW  - Fungal highways
KW  - Clonal plants
KW  - Slime molds
Y1  - 2019
U6  - https://doi.org/10.1186/s40462-019-0180-6
SN  - 2051-3933
VL  - 7
IS  - 1
PB  - BMC
CY  - London
ER  - 
TY  - JOUR
A1  - Zoll, Felix
A1  - Diehl, Katharina
A1  - Siebert, Rosemarie
T1  - Integrating sustainability goals in innovation processes
BT  - applying a decision support tool in a dual-purpose chicken case study
JF  - Sustainability
N2  - The innovative dual-purpose chicken approach aims at contributing to the transition towards sustainable poultry production by avoiding the culling of male chickens. To successfully integrate sustainability aspects into innovation, goal congruency among actors and clearly communicating the added value within the actor network and to consumers is needed. The challenge of identifying common sustainability goals calls for decision support tools. The objectives of our research were to investigate whether the tool could assist in improving communication and marketing with respect to sustainability and optimizing the value chain organization. Three actor groups participated in the tool application, in which quantitative and qualitative data were collected. The results showed that there were manifold sustainability goals within the innovation network, but only some goals overlapped, and the perception of their implementation also diverged. While easily marketable goals such as ‘animal welfare’ were perceived as being largely implemented, economic goals were prioritized less often, and the implementation was perceived as being rather low. By visualizing congruencies and differences in the goals, the tool helped identify fields of action, such as improved information flows and prompted thinking processes. We conclude that the tool is useful for managing complex decision processes with several actors involved.
KW  - value-based sustainability assessment
KW  - stakeholder participation
KW  - niche level
KW  - culling of male chickens
KW  - mixed methods
Y1  - 2019
U6  - https://doi.org/10.3390/su11143761
SN  - 2071-1050
VL  - 11
IS  - 14
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Bürger, Gerd
T1  - A seamless filter for daily to seasonal forecasts, with applications to Iran and Brazil
JF  - Quarterly Journal of the Royal Meteorological Society
N2  - A digital filter is introduced which treats the problem of predictability versus time averaging in a continuous, seamless manner. This seamless filter (SF) is characterized by a unique smoothing rule that determines the strength of smoothing in dependence on lead time. The rule needs to be specified beforehand, either by expert knowledge or by user demand. As a result, skill curves are obtained that allow a predictability assessment across a whole range of time-scales, from daily to seasonal, in a uniform manner. The SF is applied to downscaled SEAS5 ensemble forecasts for two focus regions in or near the tropical belt, the river basins of the Karun in Iran and the Sao Francisco in Brazil. Both are characterized by strong seasonality and semi-aridity, so that predictability across various time-scales is in high demand. Among other things, it is found that from the start of the water year (autumn), areal precipitation is predictable with good skill for the Karun basin two and a half months ahead; for the Sao Francisco it is only one month, longer-term prediction skill is just above the critical level.
KW  - climate drift
KW  - ensemble prediction
KW  - seamless prediction
KW  - seasonal forecast skill
Y1  - 2019
VL  - 146
IS  - 726
PB  - WILEY-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Ayzel, Georgy
A1  - Izhitskiy, Alexander
T1  - Climate Change Impact Assessment on Freshwater Inflow into the Small Aral Sea
JF  - Water
N2  - During the last few decades, the rapid separation of the Small Aral Sea from the isolated basin has changed its hydrological and ecological conditions tremendously. In the present study, we developed and validated the hybrid model for the Syr Darya River basin based on a combination of state-of-the-art hydrological and machine learning models. Climate change impact on freshwater inflow into the Small Aral Sea for the projection period 2007-2099 has been quantified based on the developed hybrid model and bias corrected and downscaled meteorological projections simulated by four General Circulation Models (GCM) for each of three Representative Concentration Pathway scenarios (RCP). The developed hybrid model reliably simulates freshwater inflow for the historical period with a Nash-Sutcliffe efficiency of 0.72 and a Kling-Gupta efficiency of 0.77. Results of the climate change impact assessment showed that the freshwater inflow projections produced by different GCMs are misleading by providing contradictory results for the projection period. However, we identified that the relative runoff changes are expected to be more pronounced in the case of more aggressive RCP scenarios. The simulated projections of freshwater inflow provide a basis for further assessment of climate change impacts on hydrological and ecological conditions of the Small Aral Sea in the 21st Century.
KW  - Small Aral Sea
KW  - hydrology
KW  - climate change
KW  - modeling
KW  - machine learning
Y1  - 2019
U6  - https://doi.org/10.3390/w11112377
SN  - 2073-4441
VL  - 11
IS  - 11
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Martin-Lopez, Berta
A1  - Leister, Ines
A1  - Cruz, Pedro Lorenzo
A1  - Palomo, Ignacio
A1  - Gret-Regamey, Adrienne
A1  - Harrison, Paula A.
A1  - Lavorel, Sandra
A1  - Locatelli, Bruno
A1  - Luque, Sandra
A1  - Walz, Ariane
T1  - Nature’s contributions to people in mountains
BT  - a review
JF  - PLoS one
N2  - Mountains play a key role in the provision of nature’s contributions to people (NCP) worldwide that support societies’ quality of life. Simultaneously, mountains are threatened by multiple drivers of change. Due to the complex interlinkages between biodiversity, quality of life and drivers of change, research on NCP in mountains requires interdisciplinary approaches. In this study, we used the conceptual framework of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) and the notion of NCP to determine to what extent previous research on ecosystem services in mountains has explored the different components of the IPBES conceptual framework. We conducted a systematic review of articles on ecosystem services in mountains published up to 2016 using the Web of Science and Scopus databases. Descriptive statistical and network analyses were conducted to explore the level of research on the components of the IPBES framework and their interactions. Our results show that research has gradually become more interdisciplinary by studying higher number of NCP, dimensions of quality of life, and indirect drivers of change. Yet, research focusing on biodiversity, regulating NCP and direct drivers has decreased over time. Furthermore, despite the fact that research on NCP in mountains becoming more policy-oriented over time, mainly in relation to payments for ecosystem services, institutional responses remained underexplored in the reviewed studies. Finally, we discuss the relevant knowledge gaps that should be addressed in future research in order to contribute to IPBES.
Y1  - 2019
U6  - https://doi.org/10.1371/journal.pone.0217847
SN  - 1932-6203
VL  - 14
IS  - 6
PB  - PLoS
CY  - San Fransisco
ER  - 
TY  - JOUR
A1  - Schoonover, Heather A.
A1  - Gret-Regamey, Adrienne
A1  - Metzger, Marc J.
A1  - Ruiz-Frau, Ana
A1  - Santos-Reis, Margarida
A1  - Scholte, Samantha S. K.
A1  - Walz, Ariane
A1  - Nicholas, Kimberly A.
T1  - Creating space, aligning motivations, and building trust
BT  - a practical framework for stakeholder engagement based on experience in 12 ecosystem services case studies
JF  - Ecology and society : a journal of integrative science for resilience and sustainability
N2  - Ecosystem services inherently involve people, whose values help define the benefits of nature's services. It is thus important for researchers to involve stakeholders in ecosystem services research. However, a simple and practicable framework to guide such engagement, and in particular to help researchers anticipate and consider key issues and challenges, has not been well explored. Here, we use experience from the 12 case studies in the European Operational Potential of Ecosystem Research Applications (OPERAs) project to propose a stakeholder engagement framework comprising three key elements: creating space, aligning motivations, and building trust. We argue that involving stakeholders in research demands thoughtful reflection from the researchers about what kind of space they want to create, including if and how they want to bring different interests together, how much space they want to allow for critical discussion, and whether there is a role for particular stakeholders to serve as conduits between others. In addition, understanding their own motivations—including values, knowledge, goals, and desired benefits—will help researchers decide when and how to involve stakeholders, identify areas of common ground and potential disagreement, frame the project appropriately, set expectations, and ensure each party is able to see benefits of engaging with each other. Finally, building relationships with stakeholders can be difficult but considering the roles of existing relationships, time, approach, reputation, and belonging can help build mutual trust. Although the three key elements and the paths between them can play out differently depending on the particular research project, we suggest that a research design that considers how to create the space in which researchers and stakeholders will meet, align motivations between researchers and stakeholders, and build mutual trust will help foster productive researcher–stakeholder relationships.
KW  - cocreated knowledge
KW  - ecosystem services
KW  - participatory research
KW  - research design
KW  - stakeholder engagement
KW  - transdisciplinary research
Y1  - 2019
U6  - https://doi.org/10.5751/ES-10061-240111
SN  - 1708-3087
VL  - 24
IS  - 1
PB  - Resilience Alliance
CY  - Wolfville
ER  - 
TY  - JOUR
A1  - Muster, Sina
A1  - Riley, William J.
A1  - Roth, Kurt
A1  - Langer, Moritz
A1  - Aleina, Fabio Cresto
A1  - Koven, Charles D.
A1  - Lange, Stephan
A1  - Bartsch, Annett
A1  - Grosse, Guido
A1  - Wilson, Cathy J.
A1  - Jones, Benjamin M.
A1  - Boike, Julia
T1  - Size distributions of arctic waterbodies reveal consistent relations in their statistical moments in space and time
JF  - Frontiers in Earth Science
N2  - Arctic lowlands are characterized by large numbers of small waterbodies, which are known to affect surface energy budgets and the global carbon cycle. Statistical analysis of their size distributions has been hindered by the shortage of observations at sufficiently high spatial resolutions. This situation has now changed with the high-resolution (<5 m) circum-Arctic Permafrost Region Pond and Lake (PeRL) database recently becoming available. We have used this database to make the first consistent, high-resolution estimation of Arctic waterbody size distributions, with surface areas ranging from 0.0001 km(2) (100 m(2)) to 1 km(2). We found that the size distributions varied greatly across the thirty study regions investigated and that there was no single universal size distribution function (including power-law distribution functions) appropriate across all of the study regions. We did, however, find close relationships between the statistical moments (mean, variance, and skewness) of the waterbody size distributions from different study regions. Specifically, we found that the spatial variance increased linearly with mean waterbody size (R-2 = 0.97, p < 2.2e-16) and that the skewness decreased approximately hyperbolically. We have demonstrated that these relationships (1) hold across the 30 Arctic study regions covering a variety of (bio)climatic and permafrost zones, (2) hold over time in two of these study regions for which multi-decadal satellite imagery is available, and (3) can be reproduced by simulating rising water levels in a high-resolution digital elevation model. The consistent spatial and temporal relationships between the statistical moments of the waterbody size distributions underscore the dominance of topographic controls in lowland permafrost areas. These results provide motivation for further analyses of the factors involved in waterbody development and spatial distribution and for investigations into the possibility of using statistical moments to predict future hydrologic dynamics in the Arctic.
KW  - permafrost
KW  - hydrology
KW  - waterbodies
KW  - size distribution
KW  - thermokarst
KW  - statistical moments
KW  - ponds
KW  - lakes
Y1  - 2019
U6  - https://doi.org/10.3389/feart.2019.00005
SN  - 2296-6463
VL  - 7
PB  - Frontiers Research Foundation
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Barbosa, Luis Romero
A1  - de Lira, Nicholas Borges
A1  - Rabelo Coelho, Victor Hugo
A1  - Bernard Passerat de Silans, Alain Marie
A1  - Gadelha, Andre Nobrega
A1  - Almeida, Cristiano das Neves
T1  - Stability of Soil Moisture Patterns Retrieved at Different Temporal Resolutions in a Tropical Watershed
JF  - Revista brasileira de ciencias do solo
N2  - Above and underground hydrological processes depend on soil moisture (SM) variability, driven by different environmental factors that seldom are well-monitored, leading to a misunderstanding of soil water temporal patterns. This study investigated the stability of the SM temporal dynamics to different monitoring temporal resolutions around the border between two soil types in a tropical watershed. Four locations were instrumented in a small-scale watershed (5.84 km(2)) within the tropical coast of Northeast Brazil, encompassing different soil types (Espodossolo Humiluvico or Carbic Podzol, and Argissolo Vermelho-Amarelo or Haplic Acrisol), land covers (Atlantic Forest, bush vegetation, and grassland) and topographies (flat and moderate slope). The SM was monitored at a temporal resolution of one hour along the 2013-2014 hydrological year and then resampled a resolutions of 6 h, 12 h, 1 day, 2 days, 4 days, 7 days, and 15 days. Descriptive statistics, temporal variability, time-stability ranking, and hierarchical clustering revealed uneven associations among SM time components. The results show that the time-invariant component ruled SM temporal variability over the time-varying parcel, either at high or low temporal resolutions. Time-steps longer than 2 days affected the mean statistical metrics of the SM time-variant parcel. Additionally, SM at downstream and upstream sites behaved differently, suggesting that the temporal mean was regulated by steady soil properties (slope, restrictive layer, and soil texture), whereas their temporal anomalies were driven by climate (rainfall) and hydrogeological (groundwater level) factors. Therefore, it is concluded that around the border between tropical soil types, the distinct behaviour of time-variant and time-invariant components of SM time series reflects different combinations of their soil properties.
KW  - soil moisture variability
KW  - time-domain reflectometry
KW  - temporal resolution
KW  - Carbic Podzol
KW  - Haplic Acrisol
Y1  - 2019
U6  - https://doi.org/10.1590/18069657rbcs20180236
SN  - 0100-0683
VL  - 43
PB  - Sociedade Brasileira de Ciencia do Solo
CY  - Vicosa
ER  - 
TY  - JOUR
A1  - Park, Jungsu
A1  - Batalla, Ramon J.
A1  - Birgand, Francois
A1  - Esteves, Michel
A1  - Gentile, Francesco
A1  - Harrington, Joseph R.
A1  - Navratil, Oldrich
A1  - Lopez-Tarazon, José Andrés
A1  - Vericat, Damia
T1  - Influences of Catchment and River Channel Characteristics on the Magnitude and Dynamics of Storage and Re-Suspension of Fine Sediments in River Beds
JF  - Water
N2  - Fine particles or sediments are one of the important variables that should be considered for the proper management of water quality and aquatic ecosystems. In the present study, the effect of catchment characteristics on the performance of an already developed model for the estimation of fine sediments dynamics between the water column and sediment bed was tested, using 13 catchments distributed worldwide. The model was calibrated to determine two optimal model parameters. The first is the filtration parameter, which represents the filtration of fine sediments through pores of the stream bed during the recession period of a flood event. The second parameter is the bed erosion parameter that represents the active layer, directly related to the re-suspension of fine sediments during a flood event. A dependency of the filtration parameter with the catchment area was observed in catchments smaller than 100 km(2), whereas no particular relationship was observed for larger catchments (>100 km(2)). In contrast, the bed erosion parameter does not show a noticeable dependency with the area or other environmental characteristics. The model estimated the mass of fine sediments released from the sediment bed to the water column during flood events in the 13 catchments within 23% bias.
KW  - bed erosion
KW  - catchment area
KW  - filtration
KW  - sediment accumulation
KW  - sediment bed fluidization
KW  - sediment re-suspension
Y1  - 2019
U6  - https://doi.org/10.3390/w11050878
SN  - 2073-4441
VL  - 11
IS  - 5
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Irrgang, Anna Maria
A1  - Lantuit, Hugues
A1  - Gordon, Richard R.
A1  - Piskor, Ashley
A1  - Manson, Gavin K.
T1  - Impacts of past and future coastal changes on the Yukon coast - threats for cultural sites, infrastructure, and travel routes
JF  - Arctic Science
N2  - Yukon’s Beaufort coast, Canada, is a highly dynamic landscape. Cultural sites, infrastructure, and travel routes used by the local population are particularly vulnerable to coastal erosion. To assess threats to these phenomena, rates of shoreline change for a 210 km length of the coast were analyzed and combined with socioeconomic and cultural information. Rates of shoreline change were derived from aerial and satellite imagery from the 1950s, 1970s, 1990s, and 2011. Using these data, conservative (S1) and dynamic (S2) shoreline projections were constructed to predict shoreline positions for the year 2100. The locations of cultural features in the archives of a Parks Canada database, the Yukon Archaeological Program, and as reported in other literature were combined with projected shoreline position changes. Between 2011 and 2100, approximately 850 ha (S1) and 2660 ha (S2) may erode, resulting in a loss of 45% (S1) to 61% (S2) of all cultural features by 2100. The last large, actively used camp area and two nearshore landing strips will likely be threatened by future coastal processes. Future coastal erosion and sedimentation processes are expected to increasingly threaten cultural sites and influence travelling and living along the Yukon coast.
KW  - Arctic coastal dynamics
KW  - permafrost coast
KW  - shoreline projection
KW  - Inuvialuit cultural features
Y1  - 2019
U6  - https://doi.org/10.1139/as-2017-0041
SN  - 2368-7460
VL  - 5
IS  - 2
SP  - 107
EP  - 126
PB  - Canadian Science Publishing
CY  - Ottawa
ER  - 
TY  - JOUR
A1  - Corti, Giacomo
A1  - Cioni, Raffaello
A1  - Franceschini, Zara
A1  - Sani, Federico
A1  - Scaillet, Stephane
A1  - Molin, Paola
A1  - Isola, Ilaria
A1  - Mazzarini, Francesco
A1  - Brune, Sascha
A1  - Keir, Derek
A1  - Erbello Doelesso, Asfaw
A1  - Muluneh, Ameha
A1  - Illsley-Kemp, Finnigan
A1  - Glerum, Anne
T1  - Aborted propagation of the Ethiopian rift caused by linkage with the Kenyan rift
JF  - Nature Communications
N2  - Continental rift systems form by propagation of isolated rift segments that interact, and eventually evolve into continuous zones of deformation. This process impacts many aspects of rifting including rift morphology at breakup, and eventual ocean-ridge segmentation. Yet, rift segment growth and interaction remain enigmatic. Here we present geological data from the poorly documented Ririba rift (South Ethiopia) that reveals how two major sectors of the East African rift, the Kenyan and Ethiopian rifts, interact. We show that the Ririba rift formed from the southward propagation of the Ethiopian rift during the Pliocene but this propagation was short-lived and aborted close to the Pliocene-Pleistocene boundary. Seismicity data support the abandonment of laterally offset, overlapping tips of the Ethiopian and Kenyan rifts. Integration with new numerical models indicates that rift abandonment resulted from progressive focusing of the tectonic and magmatic activity into an oblique, throughgoing rift zone of near pure extension directly connecting the rift sectors.
Y1  - 2019
U6  - https://doi.org/10.1038/s41467-019-09335-2
SN  - 2041-1723
VL  - 10
PB  - Nature Publ. Group
CY  - London
ER  - 
TY  - JOUR
A1  - Fairey, Brenton J.
A1  - Timmerman, Martin Jan
A1  - Sudo, Masafumi
A1  - Tsikos, Harilaos
T1  - The role of hydrothermal activity in the formation of Karst-hosted manganese deposits of the Postmasburg Mn Field, Northern Cape Province, South Africa
JF  - Minerals
N2  - The Postmasburg Manganese Field (PMF), Northern Cape Province, South Africa, once represented one of the largest sources of manganese ore worldwide. Two belts of manganese ore deposits have been distinguished in the PMF, namely the Western Belt of ferruginous manganese ores and the Eastern Belt of siliceous manganese ores. Prevailing models of ore formation in these two belts invoke karstification of manganese-rich dolomites and residual accumulation of manganese wad which later underwent diagenetic and low-grade metamorphic processes. For the most part, the role of hydrothermal processes and metasomatic alteration towards ore formation has not been adequately discussed. Here we report an abundance of common and some rare Al-, Na-, K- and Ba-bearing minerals, particularly aegirine, albite, microcline, banalsite, serandite-pectolite, paragonite and natrolite in Mn ores of the PMF, indicative of hydrothermal influence. Enrichments in Na, K and/or Ba in the ores are generally on a percentage level for most samples analysed through bulk-rock techniques. The presence of As-rich tokyoite also suggests the presence of As and V in the hydrothermal fluid. The fluid was likely oxidized and alkaline in nature, akin to a mature basinal brine. Various replacement textures, particularly of Na- and K- rich minerals by Ba-bearing phases, suggest sequential deposition of gangue as well as ore-minerals from the hydrothermal fluid, with Ba phases being deposited at a later stage. The stratigraphic variability of the studied ores and their deviation from the strict classification of ferruginous and siliceous ores in the literature, suggests that a re-evaluation of genetic models is warranted. New Ar-Ar ages for K-feldspars suggest a late Neoproterozoic timing for hydrothermal activity. This corroborates previous geochronological evidence for regional hydrothermal activity that affected Mn ores at the PMF but also, possibly, the high-grade Mn ores of the Kalahari Manganese Field to the north. A revised, all-encompassing model for the development of the manganese deposits of the PMF is then proposed, whereby the source of metals is attributed to underlying carbonate rocks beyond the Reivilo Formation of the Campbellrand Subgroup. The main process by which metals are primarily accumulated is attributed to karstification of the dolomitic substrate. The overlying Asbestos Hills Subgroup banded iron formation (BIF) is suggested as a potential source of alkali metals, which also provides a mechanism for leaching of these BIFs to form high-grade residual iron ore deposits.
KW  - manganese ore
KW  - Postmasburg manganese field
KW  - hydrothermal
KW  - karst
KW  - South Africa
Y1  - 2019
U6  - https://doi.org/10.3390/min9070408
SN  - 2075-163X
VL  - 9
IS  - 7
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Schmidt, Martin
A1  - Nendel, Claas
A1  - Funk, Roger
A1  - Mitchell, Matthew G. E.
A1  - Lischeid, Gunnar
T1  - Modeling Yields Response to Shading in the Field-to-Forest Transition Zones in Heterogeneous Landscapes
JF  - Agriculture
N2  - In crop modeling and yield predictions, the heterogeneity of agricultural landscapes is usually not accounted for. This heterogeneity often arises from landscape elements like forests, hedges, or single trees and shrubs that cast shadows. Shading from forested areas or shrubs has effects on transpiration, temperature, and soil moisture, all of which affect the crop yield in the adjacent arable land. Transitional gradients of solar irradiance can be described as a function of the distance to the zero line (edge), the cardinal direction, and the height of trees. The magnitude of yield reduction in transition zones is highly influenced by solar irradiance-a factor that is not yet implemented in crop growth models on a landscape level. We present a spatially explicit model for shading caused by forested areas, in agricultural landscapes. With increasing distance to forest, solar irradiance and yield increase. Our model predicts that the shading effect from the forested areas occurs up to 15 m from the forest edge, for the simulated wheat yields, and up to 30 m, for simulated maize. Moreover, we estimated the spatial extent of transition zones, to calculate the regional yield reduction caused by shading of the forest edges, which amounted to 5% to 8% in an exemplary region.
KW  - edge effect
KW  - transition zone
KW  - solar irradiance
KW  - crop growth
KW  - maize
KW  - wheat
Y1  - 2019
U6  - https://doi.org/10.3390/agriculture9010006
SN  - 2077-0472
VL  - 9
IS  - 1
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Freymark, Jessica
A1  - Bott, Judith
A1  - Cacace, Mauro
A1  - Ziegler, Moritz 0.
A1  - Scheck-Wenderoth, Magdalena
T1  - Influence of the Main Border Faults on the 3D Hydraulic Field of the Central Upper Rhine Graben
JF  - Geofluids
N2  - The Upper Rhine Graben (URG) is an active rift with a high geothermal potential. Despite being a well-studied area, the three-dimensional interaction of the main controlling factors of the thermal and hydraulic regime is still not fully understood. Therefore, we have used a data-based 3D structural model of the lithological configuration of the central URG for some conceptual numerical experiments of 3D coupled simulations of fluid and heat transport. To assess the influence of the main faults bordering the graben on the hydraulic and the deep thermal field, we carried out a sensitivity analysis on fault width and permeability. Depending on the assigned width and permeability of the main border faults, fluid velocity and temperatures are affected only in the direct proximity of the respective border faults. Hence, the hydraulic characteristics of these major faults do not significantly influence the graben-wide groundwater flow patterns. Instead, the different scenarios tested provide a consistent image of the main characteristics of fluid and heat transport as they have in common: (1) a topography-driven basin-wide fluid flow perpendicular to the rift axis from the graben shoulders to the rift center, (2) a N/NE-directed flow parallel to the rift axis in the center of the rift and, (3) a pronounced upflow of hot fluids along the rift central axis, where the streams from both sides of the rift merge. This upflow axis is predicted to occur predominantly in the center of the URG (northern and southern model area) and shifted towards the eastern boundary fault (central model area).
Y1  - 2019
U6  - https://doi.org/10.1155/2019/7520714
SN  - 1468-8115
SN  - 1468-8123
PB  - Wiley-Hindawi
CY  - London
ER  - 
TY  - JOUR
A1  - Didovets, Iulii
A1  - Krysanova, Valentina
A1  - Bürger, Gerd
A1  - Snizhko, Sergiy
A1  - Balabukh, Vira
A1  - Bronstert, Axel
T1  - Climate change impact on regional floods in the Carpathian region
JF  - Journal of hydrology : Regional studies
N2  - Study region: Tisza and Prut catchments, originating on the slopes of the Carpathian mountains. Study focus: The study reported here investigates (i) climate change impacts on flood risk in the region, and (ii) uncertainty related to hydrological modelling, downscaling techniques and climate projections. The climate projections used in the study were derived from five GCMs, downscaled either dynamically with RCMs or with the statistical downscaling model XDS. The resulting climate change scenarios were applied to drive the eco-hydrological model SWIM, which was calibrated and validated for the catchments in advance using observed climate and hydrological data. The changes in the 30-year flood hazards and 98 and 95 percentiles of discharge were evaluated for the far future period (2071-2100) in comparison with the reference period (1981-2010). New hydrological insights for the region: The majority of model outputs under RCP 4.5 show a small to strong increase of the 30-year flood level in the Tisza ranging from 4.5% to 62%, and moderate increase in the Prut ranging from 11% to 22%. The impact results under RCP 8.5 are more uncertain with changes in both directions due to high uncertainties in GCM-RCM climate projections, downscaling methods and the low density of available climate stations.
KW  - Climate change impact
KW  - Floods
KW  - Hydrological modelling
KW  - SWIM
KW  - Tisza
KW  - Prut
KW  - Carpathians
KW  - Ukraine
Y1  - 2019
U6  - https://doi.org/10.1016/j.ejrh.2019.01.002
SN  - 2214-5818
VL  - 22
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - von Specht, Sebastian
A1  - Öztürk, Ugur
A1  - Veh, Georg
A1  - Cotton, Fabrice
A1  - Korup, Oliver
T1  - Effects of finite source rupture on landslide triggering
BT  - the 2016 M-w 7.1 Kumamoto earthquake
JF  - Solid earth
N2  - The propagation of a seismic rupture on a fault introduces spatial variations in the seismic wave field surrounding the fault. This directivity effect results in larger shaking amplitudes in the rupture propagation direction. Its seismic radiation pattern also causes amplitude variations between the strike-normal and strike-parallel components of horizontal ground motion. We investigated the landslide response to these effects during the 2016 Kumamoto earthquake (M-w 7.1) in central Kyushu (Japan). Although the distribution of some 1500 earthquake-triggered landslides as a function of rupture distance is consistent with the observed Arias intensity, the landslides were more concentrated to the northeast of the southwest-northeast striking rupture. We examined several landslide susceptibility factors: hillslope inclination, the median amplification factor (MAF) of ground shaking, lithology, land cover, and topographic wetness. None of these factors sufficiently explains the landslide distribution or orientation (aspect), although the landslide head scarps have an elevated hillslope inclination and MAF. We propose a new physics-based ground-motion model (GMM) that accounts for the seismic rupture effects, and we demonstrate that the low-frequency seismic radiation pattern is consistent with the overall landslide distribution. Its spatial pattern is influenced by the rupture directivity effect, whereas landslide aspect is influenced by amplitude variations between the fault-normal and fault-parallel motion at frequencies < 2 Hz. This azimuth dependence implies that comparable landslide concentrations can occur at different distances from the rupture. This quantitative link between the prevalent landslide aspect and the low-frequency seismic radiation pattern can improve coseismic landslide hazard assessment.
Y1  - 2019
U6  - https://doi.org/10.5194/se-10-463-2019
SN  - 1869-9510
SN  - 1869-9529
VL  - 10
IS  - 2
SP  - 463
EP  - 486
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Haber-Pohlmeier, Sabina
A1  - Tötzke, Christian
A1  - Lehmann, E.
A1  - Kardjilov, Nikolay
A1  - Pohlmeier, A.
A1  - Oswald, Sascha
T1  - Combination of magnetic resonance imaging and neutron computed tomography for three-dimensional rhizosphere imaging
JF  - Vadose zone journal
N2  - Core Ideas

    3D MRI relaxation time maps reflect water mobility in root, rhizosphere, and soil.
    3D NCT water content maps of the same plant complement relaxation time maps.
    The relaxation time T1 decreases from soil to root, whereas water content increases.
    Parameters together indicate modification of rhizosphere pore space by gel phase.
    The zone of reduced T1 corresponds to the zone remaining dry after rewetting.

In situ investigations of the rhizosphere require high‐resolution imaging techniques, which allow a look into the optically opaque soil compartment. We present the novel combination of magnetic resonance imaging (MRI) and neutron computed tomography (NCT) to achieve synergistic information such as water mobility in terms of three‐dimensional (3D) relaxation time maps and total water content maps. Besides a stationary MRI scanner for relaxation time mapping, we used a transportable MRI system on site in the NCT facility to capture rhizosphere properties before desiccation and after subsequent rewetting. First, we addressed two questions using water‐filled test capillaries between 0.1 and 5 mm: which root diameters can still be detected by both methods, and to what extent are defined interfaces blurred by these imaging techniques? Going to real root system architecture, we demonstrated the sensitivity of the transportable MRI device by co‐registration with NCT and additional validation using X‐ray computed tomography. Under saturated conditions, we observed for the rhizosphere in situ a zone with shorter T1 relaxation time across a distance of about 1 mm that was not caused by reduced water content, as proven by successive NCT measurements. We conclude that the effective pore size in the pore network had changed, induced by a gel phase. After rewetting, NCT images showed a dry zone persisting while the MRI intensity inside the root increased considerably, indicating water uptake from the surrounding bulk soil through the still hydrophobic rhizosphere. Overall, combining NCT and MRI allows a more detailed analysis of the rhizosphere's functioning.
Y1  - 2019
U6  - https://doi.org/10.2136/vzj2018.09.0166
SN  - 1539-1663
VL  - 18
IS  - 1
PB  - Soil Science Society of America
CY  - Madison
ER  - 
TY  - JOUR
A1  - Jing, Miao
A1  - Hesse, Falk
A1  - Kumar, Rohini
A1  - Kolditz, Olaf
A1  - Kalbacher, Thomas
A1  - Attinger, Sabine
T1  - Influence of input and parameter uncertainty on the prediction of catchment-scale groundwater travel time distributions
JF  - Hydrology and earth system sciences : HESS
N2  - Groundwater travel time distributions (TTDs) provide a robust description of the subsurface mixing behavior and hydrological response of a subsurface system. Lagrangian particle tracking is often used to derive the groundwater TTDs. The reliability of this approach is subjected to the uncertainty of external forcings, internal hydraulic properties, and the interplay between them. Here, we evaluate the uncertainty of catchment groundwater TTDs in an agricultural catchment using a 3-D groundwater model with an overall focus on revealing the relationship between external forcing, internal hydraulic properties, and TTD predictions. Eight recharge realizations are sampled from a high-resolution dataset of land surface fluxes and states. Calibration-constrained hydraulic conductivity fields (Ks fields) are stochastically generated using the null-space Monte Carlo (NSMC) method for each recharge realization. The random walk particle tracking (RWPT) method is used to track the pathways of particles and compute travel times. Moreover, an analytical model under the random sampling (RS) assumption is fit against the numerical solutions, serving as a reference for the mixing behavior of the model domain. The StorAge Selection (SAS) function is used to interpret the results in terms of quantifying the systematic preference for discharging young/old water. The simulation results reveal the primary effect of recharge on the predicted mean travel time (MTT). The different realizations of calibration-constrained Ks fields moderately magnify or attenuate the predicted MTTs. The analytical model does not properly replicate the numerical solution, and it underestimates the mean travel time. Simulated SAS functions indicate an overall preference for young water for all realizations. The spatial pattern of recharge controls the shape and breadth of simulated TTDs and SAS functions by changing the spatial distribution of particles' pathways. In conclusion, overlooking the spatial nonuniformity and uncertainty of input (forcing) will result in biased travel time predictions. We also highlight the worth of reliable observations in reducing predictive uncertainty and the good interpretability of SAS functions in terms of understanding catchment transport processes.
Y1  - 2019
U6  - https://doi.org/10.5194/hess-23-171-2019
SN  - 1027-5606
SN  - 1607-7938
VL  - 23
IS  - 1
SP  - 171
EP  - 190
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Rözer, Viktor
A1  - Kreibich, Heidi
A1  - Schröter, Kai
A1  - Müller, Meike
A1  - Sairam, Nivedita
A1  - Doss-Gollin, James
A1  - Lall, Upmanu
A1  - Merz, Bruno
T1  - Probabilistic Models Significantly Reduce Uncertainty in Hurricane Harvey Pluvial Flood Loss Estimates
JF  - Earths future
N2  - Pluvial flood risk is mostly excluded in urban flood risk assessment. However, the risk of pluvial flooding is a growing challenge with a projected increase of extreme rainstorms compounding with an ongoing global urbanization. Considered as a flood type with minimal impacts when rainfall rates exceed the capacity of urban drainage systems, the aftermath of rainfall-triggered flooding during Hurricane Harvey and other events show the urgent need to assess the risk of pluvial flooding. Due to the local extent and small-scale variations, the quantification of pluvial flood risk requires risk assessments on high spatial resolutions. While flood hazard and exposure information is becoming increasingly accurate, the estimation of losses is still a poorly understood component of pluvial flood risk quantification. We use a new probabilistic multivariable modeling approach to estimate pluvial flood losses of individual buildings, explicitly accounting for the associated uncertainties. Except for the water depth as the common most important predictor, we identified the drivers for having loss or not and for the degree of loss to be different. Applying this approach to estimate and validate building structure losses during Hurricane Harvey using a property level data set, we find that the reliability and dispersion of predictive loss distributions vary widely depending on the model and aggregation level of property level loss estimates. Our results show that the use of multivariable zero-inflated beta models reduce the 90% prediction intervalsfor Hurricane Harvey building structure loss estimates on average by 78% (totalling U.S.$3.8 billion) compared to commonly used models.
KW  - pluvial flooding
KW  - loss modeling
KW  - urban flooding
KW  - probabilistic
KW  - Hurricane Harvey
KW  - climate change adaptation
Y1  - 2019
U6  - https://doi.org/10.1029/2018EF001074
SN  - 2328-4277
VL  - 7
IS  - 4
SP  - 384
EP  - 394
PB  - American Geophysical Union
CY  - Washington
ER  - 
TY  - JOUR
A1  - Sairam, Nivedita
A1  - Schröter, Kai
A1  - Lüdtke, Stefan
A1  - Merz, Bruno
A1  - Kreibich, Heidi
T1  - Quantifying Flood Vulnerability Reduction via Private Precaution
JF  - Earth future
N2  - Private precaution is an important component in contemporary flood risk management and climate adaptation. However, quantitative knowledge about vulnerability reduction via private precautionary measures is scarce and their effects are hardly considered in loss modeling and risk assessments. However, this is a prerequisite to enable temporally dynamic flood damage and risk modeling, and thus the evaluation of risk management and adaptation strategies. To quantify the average reduction in vulnerability of residential buildings via private precaution empirical vulnerability data (n = 948) is used. Households with and without precautionary measures undertaken before the flood event are classified into treatment and nontreatment groups and matched. Postmatching regression is used to quantify the treatment effect. Additionally, we test state-of-the-art flood loss models regarding their capability to capture this difference in vulnerability. The estimated average treatment effect of implementing private precaution is between 11 and 15 thousand EUR per household, confirming the significant effectiveness of private precautionary measures in reducing flood vulnerability. From all tested flood loss models, the expert Bayesian network-based model BN-FLEMOps and the rule-based loss model FLEMOps perform best in capturing the difference in vulnerability due to private precaution. Thus, the use of such loss models is suggested for flood risk assessments to effectively support evaluations and decision making for adaptable flood risk management.
KW  - flood loss
KW  - average treatment effect
KW  - matching methods
KW  - loss models
KW  - risk analysis
KW  - adaptation
Y1  - 2019
U6  - https://doi.org/10.1029/2018EF000994
SN  - 2328-4277
VL  - 7
IS  - 3
SP  - 235
EP  - 249
PB  - American Geophysical Union
CY  - Washington
ER  - 
TY  - JOUR
A1  - Herzschuh, Ulrike
A1  - Cao, Xianyong
A1  - Laepple, Thomas
A1  - Dallmeyer, Anne
A1  - Telford, Richard J.
A1  - Ni, Jian
A1  - Chen, Fahu
A1  - Kong, Zhaochen
A1  - Liu, Guangxiu
A1  - Liu, Kam-Biu
A1  - Liu, Xingqi
A1  - Stebich, Martina
A1  - Tang, Lingyu
A1  - Tian, Fang
A1  - Wang, Yongbo
A1  - Wischnewski, Juliane
A1  - Xu, Qinghai
A1  - Yan, Shun
A1  - Yang, Zhenjing
A1  - Yu, Ge
A1  - Zhang, Yun
A1  - Zhao, Yan
A1  - Zheng, Zhuo
T1  - Position and orientation of the westerly jet determined Holocene rainfall patterns in China
JF  - Nature Communications
N2  - Proxy-based reconstructions and modeling of Holocene spatiotemporal precipitation patterns for China and Mongolia have hitherto yielded contradictory results indicating that the basic mechanisms behind the East Asian Summer Monsoon and its interaction with the westerly jet stream remain poorly understood. We present quantitative reconstructions of Holocene precipitation derived from 101 fossil pollen records and analyse them with the help of a minimal empirical model. We show that the westerly jet-stream axis shifted gradually southward and became less tilted since the middle Holocene. This was tracked by the summer monsoon rain band resulting in an early-Holocene precipitation maximum over most of western China, a mid-Holocene maximum in north-central and northeastern China, and a late-Holocene maximum in southeastern China. Our results suggest that a correct simulation of the orientation and position of the westerly jet stream is crucial to the reliable prediction of precipitation patterns in China and Mongolia.
Y1  - 2019
U6  - https://doi.org/10.1038/s41467-019-09866-8
SN  - 2041-1723
VL  - 10
PB  - Nature Publ. Group
CY  - London
ER  - 
TY  - JOUR
A1  - Steirou, Eva
A1  - Gerlitz, Lars
A1  - Apel, Heiko
A1  - Sun, Xun
A1  - Merz, Bruno
T1  - Climate influences on flood probabilities across Europe
JF  - Hydrology and earth system sciences : HESS
N2  - The link between streamflow extremes and climatology has been widely studied in recent decades. However, a study investigating the effect of large-scale circulation variations on the distribution of seasonal discharge extremes at the European level is missing. Here we fit a climate-informed generalized extreme value (GEV) distribution to about 600 streamflow records in Europe for each of the standard seasons, i.e., to winter, spring, summer and autumn maxima, and compare it with the classical GEV distribution with parameters invariant in time. The study adopts a Bayesian framework and covers the period 1950 to 2016. Five indices with proven influence on the European climate are examined independently as covariates, namely the North Atlantic Oscillation (NAO), the east Atlantic pattern (EA), the east Atlantic-western Russian pattern (EA/WR), the Scandinavia pattern (SCA) and the polar-Eurasian pattern (POL). It is found that for a high percentage of stations the climate-informed model is preferred to the classical model. Particularly for NAO during winter, a strong influence on streamflow extremes is detected for large parts of Europe (preferred to the classical GEV distribution for 46% of the stations). Climate-informed fits are characterized by spatial coherence and form patterns that resemble relations between the climate indices and seasonal precipitation, suggesting a prominent role of the considered circulation modes for flood generation. For certain regions, such as northwestern Scandinavia and the British Isles, yearly variations of the mean seasonal climate indices result in considerably different extreme value distributions and thus in highly different flood estimates for individual years that can also persist for longer time periods.
Y1  - 2019
U6  - https://doi.org/10.5194/hess-23-1305-2019
SN  - 1027-5606
SN  - 1607-7938
VL  - 23
IS  - 3
SP  - 1305
EP  - 1322
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Costa Tomaz de Souza, Arthur
A1  - Ayzel, Georgy
A1  - Heistermann, Maik
T1  - Quantifying the location error of precipitation nowcasts
JF  - Advances in meteorology
N2  - In precipitation nowcasting, it is common to track the motion of precipitation in a sequence of weather radar images and to extrapolate this motion into the future. The total error of such a prediction consists of an error in the predicted location of a precipitation feature and an error in the change of precipitation intensity over lead time. So far, verification measures did not allow isolating the extent of location errors, making it difficult to specifically improve nowcast models with regard to location prediction. In this paper, we introduce a framework to directly quantify the location error. To that end, we detect and track scale-invariant precipitation features (corners) in radar images. We then consider these observed tracks as the true reference in order to evaluate the performance (or, inversely, the error) of any model that aims to predict the future location of a precipitation feature. Hence, the location error of a forecast at any lead time Delta t ahead of the forecast time t corresponds to the Euclidean distance between the observed and the predicted feature locations at t + Delta t. Based on this framework, we carried out a benchmarking case study using one year worth of weather radar composites of the German Weather Service. We evaluated the performance of four extrapolation models, two of which are based on the linear extrapolation of corner motion from t - 1 to t (LK-Lin1) and t - 4 to t (LK-Lin4) and the other two are based on the Dense Inverse Search (DIS) method: motion vectors obtained from DIS are used to predict feature locations by linear (DIS-Lin1) and Semi-Lagrangian extrapolation (DIS-Rot1). Of those four models, DIS-Lin1 and LK-Lin4 turned out to be the most skillful with regard to the prediction of feature location, while we also found that the model skill dramatically depends on the sinuosity of the observed tracks. The dataset of 376,125 detected feature tracks in 2016 is openly available to foster the improvement of location prediction in extrapolation-based nowcasting models.
KW  - inuosity
Y1  - 2020
U6  - https://doi.org/10.1155/2020/8841913
SN  - 1687-9309
SN  - 1687-9317
VL  - 2020
PB  - Hindawi
CY  - London
ER  - 
TY  - JOUR
A1  - Oguntunde, Philip G.
A1  - Abiodun, Babatunde Joseph
A1  - Lischeid, Gunnar
A1  - Abatan, Abayomi A.
T1  - Droughts projection over the Niger and Volta River basins of West Africa at specific global warming levels
JF  - International Journal of Climatology
N2  - This study investigates possible impacts of four global warming levels (GWLs: GWL1.5, GWL2.0, GWL2.5, and GWL3.0) on drought characteristics over Niger River basin (NRB) and Volta River basin (VRB). Two drought indices-Standardized Precipitation Index (SPI) and Standardized Precipitation-Evapotranspiration Index (SPEI)-were employed in characterizing droughts in 20 multi-model simulation outputs from the Coordinated Regional Climate Downscaling Experiment (CORDEX). The performance of the simulation in reproducing basic hydro-climatological features and severe drought characteristics (i.e., magnitude and frequency) in the basins were evaluated. The projected changes in the future drought frequency were quantified and compared under the four GWLs for two climate forcing scenarios (RCP8.5 and RCP4.5). The regional climate model (RCM) ensemble gives a realistic simulation of historical hydro-climatological variables needed to calculate the drought indices. With SPEI, the simulation ensemble projects an increase in the magnitude and frequency of severe droughts over both basins (NRB and VRB) at all GWLs, but the increase, which grows with the GWLs, is higher over NRB than over VRB. More than 75% of the simulations agree on the projected increase at GWL1.5 and all simulations agree on the increase at higher GWLs. With SPI, the projected changes in severe drought is weaker and the magnitude remains the same at all GWLs, suggesting that SPI projection may underestimate impacts of the GWLs on the intensity and severity of future drought. The results of this study have application in mitigating impact of global warming on future drought risk over the regional water systems.
KW  - climate change
KW  - drought index
KW  - global warming levels
KW  - river basins
KW  - West Africa
KW  - CORDEX data
Y1  - 2019
VL  - 40
IS  - 13
PB  - John Wiley & Sons, Inc.
CY  - New Jersey
ER  - 
TY  - JOUR
A1  - Marcisz, Katarzyna
A1  - Jassey, Vincent E. J.
A1  - Kosakyan, Anush
A1  - Krashevska, Valentyna
A1  - Lahr, Daniel J. G.
A1  - Lara, Enrique
A1  - Lamentowicz, Lukasz
A1  - Lamentowicz, Mariusz
A1  - Macumber, Andrew
A1  - Mazei, Yuri
A1  - Mitchell, Edward A. D.
A1  - Nasser, Nawaf A.
A1  - Patterson, R. Timothy
A1  - Roe, Helen M.
A1  - Singer, David
A1  - Tsyganov, Andrey N.
A1  - Fournier, Bertrand
T1  - Testate amoeba functional traits and their use in paleoecology
JF  - Frontiers in Ecology and Evolution
N2  - This review provides a synthesis of current knowledge on the morphological and functional traits of testate amoebae, a polyphyletic group of protists commonly used as proxies of past hydrological changes in paleoecological investigations from peatland, lake sediment and soil archives. A trait-based approach to understanding testate amoebae ecology and paleoecology has gained in popularity in recent years, with research showing that morphological characteristics provide complementary information to the commonly used environmental inferences based on testate amoeba (morpho-)species data. We provide a broad overview of testate amoeba morphological and functional traits and trait-environment relationships in the context of ecology, evolution, genetics, biogeography, and paleoecology. As examples we report upon previous ecological and paleoecological studies that used trait-based approaches, and describe key testate amoebae traits that can be used to improve the interpretation of environmental studies. We also highlight knowledge gaps and speculate on potential future directions for the application of trait-based approaches in testate amoeba research.
KW  - protists
KW  - functional traits
KW  - morphological traits
KW  - ecology
KW  - peatlands
KW  - lakes
KW  - soils
KW  - trait-based approaches
Y1  - 2020
U6  - https://doi.org/10.3389/fevo.2020.575966
SN  - 2296-701X
VL  - 8
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Zingraff-Hamed, Aude
A1  - Hüesker, Frank
A1  - Lupp, Gerd
A1  - Begg, Chloe
A1  - Huang, Josh
A1  - Oen, Amy M. P.
A1  - Vojinović, Zoran
A1  - Kuhlicke, Christian
A1  - Pauleit, Stephan
T1  - Stakeholder mapping to co-create nature-based solutions
BT  - who is on board?
JF  - Sustainability
N2  - Nature-based solutions (NBS) are inspired and supported by nature but designed by humans. Historically, governmental stakeholders have aimed to control nature using a top-down approach; more recently, environmental governance has shifted to collaborative planning. Polycentric governance and co-creation procedures, which include a large spectrum of stakeholders, are assumed to be more effective in the management of public goods than traditional approaches. In this context, NBS projects should benefit from strong collaborative governance models, and the European Union is facilitating and encouraging such models. While some theoretical approaches exist, setting-up the NBS co-creation process (namely co-design and co-implementation) currently relies mostly on self-organized stakeholders rather than on strategic decisions. As such, systematic methods to identify relevant stakeholders seem to be crucial to enable higher planning efficiency, reduce bottlenecks and time needed for planning, designing, and implementing NBS. In this context, this contribution is based on the analysis of 16 NBS and 359 stakeholders. Real-life constellations are compared to theoretical typologies, and a systematic stakeholder mapping method to support co-creation is presented. Rather than making one-fit-all statements about the "right" stakeholders, the contribution provides insights for those "in charge" to strategically consider who might be involved at each stage of the NBS project.
KW  - ecosystem-based
KW  - natural hazard mitigation
KW  - participative planning
KW  - co-design
KW  - polycentric governance
KW  - living labs
KW  - societal resilience
KW  - sustainable development goals
Y1  - 2020
U6  - https://doi.org/10.3390/su12208625
SN  - 2071-1050
VL  - 12
IS  - 20
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - de Brito, Mariana Madruga
A1  - Kuhlicke, Christian
A1  - Marx, Andreas
T1  - Near-real-time drought impact assessment
BT  - a text mining approach on the 2018/19 drought in Germany
JF  - Environmental research letters
N2  - Contemporary drought impact assessments have been constrained due to data availability, leading to an incomplete representation of impact trends. To address this, we present a novel method for the comprehensive and near-real-time monitoring of drought socio-economic impacts based on media reports. We tested its application using the case of the exceptional 2018/19 German drought. By employing text mining techniques, 4839 impact statements were identified, relating to livestock, agriculture, forestry, fires, recreation, energy and transport sectors. An accuracy of 95.6% was obtained for their automatic classification. Furthermore, high levels of performance in terms of spatial and temporal precision were found when validating our results against independent data (e.g. soil moisture, average precipitation, population interest in droughts, crop yield and forest fire statistics). The findings highlight the applicability of media data for rapidly and accurately monitoring the propagation of drought consequences over time and space. We anticipate our method to be used as a starting point for an impact-based early warning system.
KW  - drought impacts
KW  - Germany
KW  - text analytics
KW  - newspaper
KW  - validation
Y1  - 2020
U6  - https://doi.org/10.1088/1748-9326/aba4ca
SN  - 1748-9326
VL  - 15
IS  - 10
PB  - IOP Publ.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Hudson, Paul
A1  - Hagedoorn, Liselotte
A1  - Bubeck, Philip
T1  - Potential linkages between social capital, flood risk perceptions, and self-efficacy
JF  - International journal of disaster risk science
N2  - A growing focus is being placed on both individuals and communities to adapt to flooding as part of the Sendai Framework for Disaster Risk Reduction 2015-2030. Adaptation to flooding requires sufficient social capital (linkages between members of society), risk perceptions (understanding of risk), and self-efficacy (self-perceived ability to limit disaster impacts) to be effective. However, there is limited understanding of how social capital, risk perceptions, and self-efficacy interact. We seek to explore how social capital interacts with variables known to increase the likelihood of successful adaptation. To study these linkages we analyze survey data of 1010 respondents across two communities in Thua Tien-Hue Province in central Vietnam, using ordered probit models. We find positive correlations between social capital, risk perceptions, and self-efficacy overall. This is a partly contrary finding to what was found in previous studies linking these concepts in Europe, which may be a result from the difference in risk context. The absence of an overall negative exchange between these factors has positive implications for proactive flood risk adaptation.
KW  - flood risk
KW  - protection motivation theory
KW  - risk perceptions
KW  - social
KW  - capital
KW  - self-efficacy
KW  - Vietnam
Y1  - 2020
U6  - https://doi.org/10.1007/s13753-020-00259-w
SN  - 2095-0055
SN  - 2192-6395
VL  - 11
IS  - 3
SP  - 251
EP  - 262
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Webber, Heidi
A1  - Lischeid, Gunnar
A1  - Sommer, Michael
A1  - Finger, Robert
A1  - Nendel, Claas
A1  - Gaiser, Thomas
A1  - Ewert, Frank
T1  - No perfect storm for crop yield failure in Germany
JF  - Environmental research letters
N2  - Large-scale crop yield failures are increasingly associated with food price spikes and food insecurity and are a large source of income risk for farmers. While the evidence linking extreme weather to yield failures is clear, consensus on the broader set of weather drivers and conditions responsible for recent yield failures is lacking. We investigate this for the case of four major crops in Germany over the past 20 years using a combination of machine learning and process-based modelling. Our results confirm that years associated with widespread yield failures across crops were generally associated with severe drought, such as in 2018 and to a lesser extent 2003. However, for years with more localized yield failures and large differences in spatial patterns of yield failures between crops, no single driver or combination of drivers was identified. Relatively large residuals of unexplained variation likely indicate the importance of non-weather related factors, such as management (pest, weed and nutrient management and possible interactions with weather) explaining yield failures. Models to inform adaptation planning at farm, market or policy levels are here suggested to require consideration of cumulative resource capture and use, as well as effects of extreme events, the latter largely missing in process-based models. However, increasingly novel combinations of weather events under climate change may limit the extent to which data driven methods can replace process-based models in risk assessments.
KW  - crop yield failure
KW  - extreme events
KW  - support vector machine
KW  - process-based crop model
KW  - Germany
Y1  - 2020
U6  - https://doi.org/10.1088/1748-9326/aba2a4
SN  - 1748-9326
VL  - 15
IS  - 10
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Tesselaar, Max
A1  - Botzen, W. J. Wouter
A1  - Haer, Toon
A1  - Hudson, Paul
A1  - Tiggeloven, Timothy
A1  - Aerts, Jeroen C. J. H.
T1  - Regional inequalities in flood insurance affordability and uptake under climate change
JF  - Sustainability
N2  - Flood insurance coverage can enhance financial resilience of households to changing flood risk caused by climate change. However, income inequalities imply that not all households can afford flood insurance. The uptake of flood insurance in voluntary markets may decline when flood risk increases as a result of climate change. This increase in flood risk may cause substantially higher risk-based insurance premiums, reduce the willingness to purchase flood insurance, and worsen problems with the unaffordability of coverage for low-income households. A socio-economic tipping-point can occur when the functioning of a formal flood insurance system is hampered by diminishing demand for coverage. In this study, we examine whether such a tipping-point can occur in Europe for current flood insurance systems under different trends in future flood risk caused by climate and socio-economic change. This analysis gives insights into regional inequalities concerning the ability to continue to use flood insurance as an instrument to adapt to changing flood risk. For this study, we adapt the "Dynamic Integrated Flood and Insurance" (DIFI) model by integrating new flood risk simulations in the model that enable examining impacts from various scenarios of climate and socio-economic change on flood insurance premiums and consumer demand. Our results show rising unaffordability and declining demand for flood insurance across scenarios towards 2080. Under a high climate change scenario, simulations show the occurrence of a socio-economic tipping-point in several regions, where insurance uptake almost disappears. A tipping-point and related inequalities in the ability to use flood insurance as an adaptation instrument can be mitigated by introducing reforms of flood insurance arrangements.
KW  - climate change
KW  - flood risk management
KW  - insurance
KW  - socio-economic
KW  - tipping-point
KW  - adaptation
KW  - partial equilibrium modeling
Y1  - 2020
U6  - https://doi.org/10.3390/su12208734
SN  - 2071-1050
VL  - 12
IS  - 20
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Pan, Xiaohui
A1  - Wang, Weishi
A1  - Liu, Tie
A1  - Huang, Yue
A1  - De Maeyer, Philippe
A1  - Guo, Chenyu
A1  - Ling, Yunan
A1  - Akmalov, Shamshodbek
T1  - Quantitative detection and attribution of groundwater level variations in the Amu Darya Delta
JF  - Water
N2  - In the past few decades, the shrinkage of the Aral Sea is one of the biggest ecological catastrophes caused by human activity. To quantify the joint impact of both human activities and climate change on groundwater, the spatiotemporal groundwater dynamic characteristics in the Amu Darya Delta of the Aral Sea from 1999 to 2017 were analyzed, using the groundwater level, climate conditions, remote sensing data, and irrigation information. Statistics analysis was adopted to analyze the trend of groundwater variation, including intensity, periodicity, spatial structure, while the Pearson correlation analysis and principal component analysis (PCA) were used to quantify the impact of climate change and human activities on the variabilities of the groundwater level. Results reveal that the local groundwater dynamic has varied considerably. From 1999 to 2002, the groundwater level dropped from -189 cm to -350 cm. Until 2017, the groundwater level rose back to -211 cm with fluctuation. Seasonally, the fluctuation period of groundwater level and irrigation water was similar, both were about 18 months. Spatially, the groundwater level kept stable within the irrigation area and bare land but fluctuated drastically around the irrigation area. The Pearson correlation analysis reveals that the dynamic of the groundwater level is closely related to irrigation activity within the irrigation area (Nukus: -0.583), while for the place adjacent to the Aral Sea, the groundwater level is closely related to the Large Aral Sea water level (Muynak: 0.355). The results of PCA showed that the cumulative contribution rate of the first three components exceeds 85%. The study reveals that human activities have a great impact on groundwater, effective management, and the development of water resources in arid areas is an essential prerequisite for ecological protection.
KW  - groundwater level variation
KW  - climate change
KW  - human activities
KW  - statistical analysis
KW  - Amu Darya Delta
Y1  - 2020
U6  - https://doi.org/10.3390/w12102869
SN  - 2073-4441
VL  - 12
IS  - 10
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Natho, Stephanie
A1  - Tschikof, Martin
A1  - Bondar-Kunze, Elisabeth
A1  - Hein, Thomas
T1  - Modeling the effect of enhanced lateral connectivity on nutrient retention capacity in large river floodplains
BT  - how much connected floodplain do we need?
JF  - Frontiers in Environmental Science
N2  - Floodplains have been degraded in Central Europe for centuries, resulting in less dynamic and less diverse ecosystems than in the past. They provide essential ecosystem services like nutrient retention to improve overall water quality and thus fulfill naturally what EU legislation demands, but this service is impaired by reduced connectivity patterns. Along the second-longest river in Europe, the Danube, restoration measures have been carried out and are planned for the near future in the Austrian Danube Floodplain National Park in accordance with navigation purposes. We investigated nutrient retention capacity in seven currently differently connected side arms and the effects of proposed restoration measures using two complementary modeling approaches. We modeled nutrient retention capacity in two scenarios considering different hydrological conditions, as well as the consequences of planned restoration measures for side arm connectivity. With existing monitoring data on hydrology, nitrate, and total phosphorus concentrations for three side arms, we applied a statistical model and compared these results to a semi-empirical retention model. The latter was originally developed for larger scales, based on transferable causalities of retention processes and set up for this floodplain with publicly available data. Both model outcomes are in a comparable range for NO3-N (77-198 kg ha(-1)yr(-1)) and TP (1.4-5.7 kg ha(-1)yr(-1)) retention and agree in calculating higher retention in floodplains, where reconnection allows more frequent inundation events. However, the differences in the model results are significant for specific aspects especially during high flows, where the semi-empirical model complements the statistical model. On the other hand, the statistical model complements the semi-empirical model when taking into account nutrient retention at times of no connection between the remaining water bodies left in the floodplain. Overall, both models show clearly that nutrient retention in the Danube floodplains can be enhanced by restoring lateral hydrological reconnection and, for all planned measures, a positive effect on the overall water quality of the Danube River is expected. Still, a frequently hydrologically connected stretch of national park is insufficient to improve the water quality of the whole Upper Danube, and more functional floodplains are required.
KW  - floodplain
KW  - lateral hydrological connectivity
KW  - Danube
KW  - restoration
KW  - reconnection
KW  - inundation
KW  - nutrient retention
KW  - modeling
Y1  - 2020
U6  - https://doi.org/10.3389/fenvs.2020.00074
SN  - 2296-665X
VL  - 8
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Lehr, Christian
A1  - Lischeid, Gunnar
T1  - Efficient screening of groundwater head monitoring data for anthropogenic effects and measurement errors
JF  - Hydrology and Earth System Sciences
N2  - Groundwater levels are monitored by environmental agencies to support the sustainable use of groundwater resources. For this purpose continuous and spatially comprehensive monitoring in high spatial and temporal resolution is desired. This leads to large datasets that have to be checked for quality and analysed to distinguish local anthropogenic influences from natural variability of the groundwater level dynamics at each well. Both technical problems with the measurements as well as local anthropogenic influences can lead to local anomalies in the hydrographs. We suggest a fast and efficient screening method for the identification of well-specific peculiarities in hydrographs of groundwater head monitoring networks. The only information required is a set of time series of groundwater heads all measured at the same instants of time. For each well of the monitoring network a reference hydrograph is calculated, describing expected "normal" behaviour at the respective well as is typical for the monitored region. The reference hydrograph is calculated by multiple linear regression of the observed hydrograph with the "stable" principal components (PCs) of a principal component analysis of all groundwater head series of the network as predictor variables. The stable PCs are those PCs which were found in a random subsampling procedure to be rather insensitive to the specific selection of the analysed observation wells, i.e. complete series, and to the specific selection of measurement dates. Hence they can be considered to be representative for the monitored region in the respective period. The residuals of the reference hydrograph describe local deviations from the normal behaviour. Peculiarities in the residuals allow the data to be checked for measurement errors and the wells with a possible anthropogenic influence to be identified. The approach was tested with 141 groundwater head time series from the state authority groundwater monitoring network in northeastern Germany covering the period from 1993 to 2013 at an approximately weekly frequency of measurement.
KW  - streamflow variability
KW  - principal components
KW  - united states
KW  - time-seriesa
KW  - water
KW  - network
KW  - nonstationarity
KW  - fluctuations
KW  - rotation
Y1  - 2020
U6  - https://doi.org/10.5194/hess-24-501-2020
SN  - 1027-5606
SN  - 1607-7938
VL  - 24
IS  - 2
SP  - 501
EP  - 513
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Zimmermann, Heike Hildegard
A1  - Stoof-Leichsenring, Kathleen Rosemarie
A1  - Kruse, Stefan
A1  - Müller, Juliane
A1  - Stein, Ruediger
A1  - Tiedemann, Ralf
A1  - Herzschuh, Ulrike
T1  - Changes in the composition of marine and sea-ice diatoms derived from sedimentary ancient DNA of the eastern Fram Strait over the past 30 000 years
JF  - Ocean Science
N2  - The Fram Strait is an area with a relatively low and irregular distribution of diatom microfossils in surface sediments, and thus microfossil records are scarce, rarely exceed the Holocene, and contain sparse information about past richness and taxonomic composition. These attributes make the Fram Strait an ideal study site to test the utility of sedimentary ancient DNA (sedaDNA) metabarcoding. Amplifying a short, partial rbcL marker from samples of sediment core MSM05/5-712-2 resulted in 95.7 % of our sequences being assigned to diatoms across 18 different families, with 38.6 % of them being resolved to species and 25.8 % to genus level. Independent replicates show a high similarity of PCR products, especially in the oldest samples. Diatom sedaDNA richness is highest in the Late Weichselian and lowest in Mid- and Late Holocene samples. Taxonomic composition is dominated by cold-water and sea-ice-associated diatoms and suggests several reorganisations – after the Last Glacial Maximum, after the Younger Dryas, and after the Early and after the Mid-Holocene. Different sequences assigned to, amongst others, Chaetoceros socialis indicate the detectability of intra-specific diversity using sedaDNA. We detect no clear pattern between our diatom sedaDNA record and the previously published IP25 record of this core, although proportions of pennate diatoms increase with higher IP25 concentrations and proportions of Nitzschia cf. frigida exceeding 2 % of the assemblage point towards past sea-ice presence.
KW  - last glacial maximum
KW  - surface temperatures
KW  - species composition
KW  - greenland shelf
KW  - Disko Bay
KW  - phytoplankton
KW  - communities
KW  - variability
KW  - diversity
KW  - Svalbard
Y1  - 2019
VL  - 16
IS  - 5
PB  - Springer
CY  - Tokyo
ER  - 
TY  - JOUR
A1  - Zhang, Yan-qiu
A1  - Guo, Zeng-hui
A1  - Chen, Dai-zhao
T1  - Porosity distribution in cyclic dolomites of the Lower Qiulitag Group (Upper Cambrian) in northwestern Tarim Basin, China
JF  - China geology
N2  - Increasing interests in hydrocarbon resources at depths have drawn greater attentions to the deeply-buried carbonate reservoirs in the Tarim Basin in China. In this study, the cyclic dolomite rocks of Upper Cambrian Lower Qiulitag Group from four outcrop sections in northwestern Tarim Basin were selected to investigate and evaluate the petrophysical properties in relation to depositional facies and cyclicity. The Lower Qiulitag Group includes ten lithofacies, which were deposited in intermediate to shallow subtidal, restricted shallow subtidal, intertidal, and supratidal environments on a carbonate ramp system. These lithofacies are vertically stacked into repeated shallowing-upward, meter-scale cycles which are further grouped into six third-order depositional sequences (Sq1 to Sq6). There are variable types of pore spaces in the Lower Qiulitag Group dolomite rocks, including interparticle, intraparticle, and fenestral pores of primary origin, inter crystal, and vuggy pores of late diagenetic modification. The porosity in the dolomites is generally facies-selective as that the microbially-originated thrombolites and stromatolites generally yield a relatively high porosity. In contrast, the high-energy ooidal grainstones generally have very low porosity. In this case, the microbialite-based peritidal cycles and peritidal cycle-dominated highstand (or regressive) successions have relatively high volumes of pore spaces, although highly fluctuating (or vertical inhomogeneous). Accordingly, the grainstone-based subtidal cycles and subtidal cycle-dominated transgressive successions generally yield extremely low porosity. This scenario indicates that porosity development and preservation in the thick dolomite successions are primarily controlled by depositional facies which were influenced by sea-level fluctuations of different orders and later diagenetic overprinting.
KW  - Dolomites
KW  - porosity
KW  - cyclicity
KW  - Upper Cambrian
KW  - stromatolite
KW  - microbial
KW  - build up
KW  - oil-gas basin
KW  - oil-gas exploration engineering
KW  - Tarim Basin
KW  - China
Y1  - 2020
UR  - http://en.cgsjournals.com/zgdzdcqkw-data/zgdzyw/2020/3/PDF/cg2020026.pdf
SN  - 2096-5192
SN  - 2589-9430
VL  - 3
IS  - 3
SP  - 425
EP  - 444
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Dobkowitz, Sophia
A1  - Walz, Ariane
A1  - Baroni, Gabriele
A1  - Pérez-Marin, Aldrin M.
T1  - Cross-Scale Vulnerability Assessment for Smallholder Farming
BT  - A Case Study from the Northeast of Brazil
JF  - Sustainability
N2  - Climate change heavily impacts smallholder farming worldwide. Cross-scale vulnerability assessment has a high potential to identify nested measures for reducing vulnerability of smallholder farmers. Despite their high practical value, there are currently only limited examples of cross-scale assessments. The presented study aims at assessing the vulnerability of smallholder farmers in the Northeast of Brazil across three scales: regional, farm and field scale. In doing so, it builds on existing vulnerability indices and compares results between indices at the same scale and across scales. In total, six independent indices are tested, two at each scale. The calculated indices include social, economic and ecological indicators, based on municipal statistics, meteorological data, farm interviews and soil analyses. Subsequently, indices and overlapping indicators are normalized for intra- and cross-scale comparison. The results show considerable differences between indices across and within scales. They indicate different activities to reduce vulnerability of smallholder farmers. Major shortcomings arise from the conceptual differences between the indices. We therefore recommend the development of hierarchical indices, which are adapted to local conditions and contain more overlapping indicators for a better understanding of the nested vulnerabilities of smallholder farmers.
KW  - family farming
KW  - nested vulnerabilities
KW  - vulnerability indices
KW  - semi-arid regions
KW  - Paraíba
Y1  - 2020
U6  - https://doi.org/10.3390/su12093787
SN  - 2071-1050
VL  - 12
IS  - 9
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Scherler, Dirk
A1  - Schwanghart, Wolfgang
T1  - Drainage divide networks - part 1: Identification and ordering in digital elevation models
JF  - Earth surface dynamics : ESURF
N2  - We propose a novel way to measure and analyze networks of drainage divides from digital elevation models. We developed an algorithm that extracts drainage divides based on the drainage basin boundaries defined by a stream network. In contrast to streams, there is no straightforward approach to order and classify divides, although it is intuitive that some divides are more important than others. A meaningful way of ordering divides is the average distance one would have to travel down on either side of a divide to reach a common stream location. However, because measuring these distances is computationally expensive and prone to edge effects, we instead sort divide segments based on their tree-like network structure, starting from endpoints at river confluences. The sorted nature of the network allows for assigning distances to points along the divides, which can be shown to scale with the average distance downslope to the common stream location. Furthermore, because divide segments tend to have characteristic lengths, an ordering scheme in which divide orders increase by 1 at junctions mimics these distances. We applied our new algorithm to the Big Tujunga catchment in the San Gabriel Mountains of southern California and studied the morphology of the drainage divide network. Our results show that topographic metrics, like the downstream flow distance to a stream and hillslope relief, attain characteristic values that depend on the drainage area threshold used to derive the stream network. Portions along the divide network that have lower than average relief or are closer than average to streams are often distinctly asymmetric in shape, suggesting that these divides are unstable. Our new and automated approach thus helps to objectively extract and analyze divide networks from digital elevation models.
Y1  - 2020
U6  - https://doi.org/10.5194/esurf-8-245-2020
SN  - 2196-6311
SN  - 2196-632X
VL  - 8
IS  - 2
SP  - 245
EP  - 259
PB  - Copernicus Publ.
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Herrero, Mario
A1  - Thornton, Philip K.
A1  - Mason-D'Croz, Daniel
A1  - Palmer, Jeda
A1  - Bodirsky, Benjamin Leon
A1  - Pradhan, Prajal
A1  - Barrett, Christopher B.
A1  - Benton, Tim G.
A1  - Hall, Andrew
A1  - Pikaar, Ilje
A1  - Bogard, Jessica R.
A1  - Bonnett, Graham D.
A1  - Bryan, Brett A.
A1  - Campbell, Bruce M.
A1  - Christensen, Svend
A1  - Clark, Michael
A1  - Fanzo, Jessica
A1  - Godde, Cecile M.
A1  - Jarvis, Andy
A1  - Loboguerrero, Ana Maria
A1  - Mathys, Alexander
A1  - McIntyre, C. Lynne
A1  - Naylor, Rosamond L.
A1  - Nelson, Rebecca
A1  - Obersteiner, Michael
A1  - Parodi, Alejandro
A1  - Popp, Alexander
A1  - Ricketts, Katie
A1  - Smith, Pete
A1  - Valin, Hugo
A1  - Vermeulen, Sonja J.
A1  - Vervoort, Joost
A1  - van Wijk, Mark
A1  - van Zanten, Hannah H. E.
A1  - West, Paul C.
A1  - Wood, Stephen A.
A1  - Rockström, Johan
T1  - Articulating the effect of food systems innovation on the Sustainable Development Goals
JF  - The lancet Planetary health
N2  - Food system innovations will be instrumental to achieving multiple Sustainable Development Goals (SDGs). However, major innovation breakthroughs can trigger profound and disruptive changes, leading to simultaneous and interlinked reconfigurations of multiple parts of the global food system. The emergence of new technologies or social solutions, therefore, have very different impact profiles, with favourable consequences for some SDGs and unintended adverse side-effects for others. Stand-alone innovations seldom achieve positive outcomes over multiple sustainability dimensions. Instead, they should be embedded as part of systemic changes that facilitate the implementation of the SDGs. Emerging trade-offs need to be intentionally addressed to achieve true sustainability, particularly those involving social aspects like inequality in its many forms, social justice, and strong institutions, which remain challenging. Trade-offs with undesirable consequences are manageable through the development of well planned transition pathways, careful monitoring of key indicators, and through the implementation of transparent science targets at the local level.
Y1  - 2020
U6  - https://doi.org/10.1016/S2542-5196(20)30277-1
SN  - 2542-5196
VL  - 5
IS  - 1
SP  - E50
EP  - E62
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Koç, Gamze
A1  - Petrow, Theresia
A1  - Thieken, Annegret
T1  - Analysis of the Most Severe Flood Events in Turkey (1960–2014)
BT  - Which Triggering Mechanisms and Aggravating Pathways Can be Identified?
JF  - Water
N2  - The most severe flood events in Turkey were determined for the period 1960–2014 by considering the number of fatalities, the number of affected people, and the total economic losses as indicators. The potential triggering mechanisms (i.e., atmospheric circulations and precipitation amounts) and aggravating pathways (i.e., topographic features, catchment size, land use types, and soil properties) of these 25 events were analyzed. On this basis, a new approach was developed to identify the main influencing factor per event and to provide additional information for determining the dominant flood occurrence pathways for severe floods. The events were then classified through hierarchical cluster analysis. As a result, six different clusters were found and characterized. Cluster 1 comprised flood events that were mainly influenced by drainage characteristics (e.g., catchment size and shape); Cluster 2 comprised events aggravated predominantly by urbanization; steep topography was identified to be the dominant factor for Cluster 3; extreme rainfall was determined as the main triggering factor for Cluster 4; saturated soil conditions were found to be the dominant factor for Cluster 5; and orographic effects of mountain ranges characterized Cluster 6. This study determined pathway patterns of the severe floods in Turkey with regard to their main causal or aggravating mechanisms. Accordingly, geomorphological properties are of major importance in large catchments in eastern and northeastern Anatolia. In addition, in small catchments, the share of urbanized area seems to be an important factor for the extent of flood impacts. This paper presents an outcome that could be used for future urban planning and flood risk prevention studies to understand the flood mechanisms in different regions of Turkey.
KW  - hierarchical clustering
KW  - Hess-Brezowsky Großwetterlagen classification
KW  - ERA5
KW  - flood hazards
KW  - pathway
KW  - Turkey
Y1  - 2020
U6  - https://doi.org/10.3390/w12061562
SN  - 2073-4441
VL  - 12
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Laudan, Jonas
A1  - Zöller, Gert
A1  - Thieken, Annegret
T1  - Flash floods versus river floods
BT  - a comparison of psychological impacts and implications for precautionary behaviour
JF  - Natural Hazards and Earth System Sciences
N2  - River floods are among the most damaging natural hazards that frequently occur in Germany. Flooding causes high economic losses and impacts many residents. In 2016, several southern German municipalities were hit by flash floods after unexpectedly severe heavy rainfall, while in 2013 widespread river flooding had occurred. This study investigates and compares the psychological impacts of river floods and flash floods and potential consequences for precautionary behaviour. Data were collected using computer-aided telephone interviews that were conducted among flood-affected households around 9 months after each damaging event. This study applies Bayesian statistics and negative binomial regressions to test the suitability of psychological indicators to predict the precaution motivation of individuals. The results show that it is not the particular flood type but rather the severity and local impacts of the event that are crucial for the different, and potentially negative, impacts on mental health. According to the used data, however, predictions of the individual precaution motivation should not be based on the derived psychological indicators – i.e. coping appraisal, threat appraisal, burden and evasion – since their explanatory power was generally low and results are, for the most part, non-significant. Only burden reveals a significant positive relation to planned precaution regarding weak flash floods. In contrast to weak flash floods and river floods, the perceived threat of strong flash floods is significantly lower although feelings of burden and lower coping appraisals are more pronounced. Further research is needed to better include psychological assessment procedures and to focus on alternative data sources regarding floods and the connected precaution motivation of affected residents.
KW  - private households
KW  - risk perceptions
KW  - extreme rainfall
KW  - health
KW  - mitigation
KW  - Germany
KW  - people
KW  - damage
KW  - preparedness
KW  - residents
Y1  - 2019
U6  - https://doi.org/10.5194/nhess-20-999-2020
SN  - 1684-9981
VL  - 20
SP  - 999
EP  - 1023
PB  - European Geophysical Society
CY  - Katlenburg-Lindau
ER  - 
TY  - JOUR
A1  - Hudson, Paul
A1  - Pham, My
A1  - Hagedoorn, Liselotte
A1  - Thieken, Annegret
A1  - Lasage, Ralph
A1  - Bubeck, Philip
T1  - Self-stated recovery from flooding
BT  - empirical results from a survey in Central Vietnam
JF  - Journal of Flood Risk Management
N2  - Social inequalities lead to flood resilience inequalities across social groups, a topic that requires improved documentation and understanding. The objective of this paper is to attend to these differences by investigating self-stated flood recovery across genders in Vietnam as a conceptual replication of earlier results from Germany. This study employs a regression-based analysis of 1,010 respondents divided between a rural coastal and an urban community in Thua Thien-Hue province. The results highlight an important set of recovery process-related variables. The set of relevant variables is similar across genders in terms of inclusion and influence, and includes age, social capital, internal and external support after a flood, perceived severity of previous flood impacts, and the perception of stress-resilience. However, women were affected more heavily by flooding in terms of longer recovery times, which should be accounted for in risk management. Overall, the studied variables perform similarly in Vietnam and Germany. This study, therefore, conceptually replicates previous results suggesting that women display slightly slower recovery levels as well as that psychological variables influence recovery rates more than adverse flood impacts. This provides an indication of the results' potentially robust nature due to the different socio-environmental contexts in Germany and Vietnam.
KW  - flood recovery
KW  - resilience
KW  - societal equity
KW  - vulnerability
Y1  - 2020
U6  - https://doi.org/10.1111/jfr3.12680
SN  - 1753-318X
VL  - 14
PB  - Wiley-Blackwell
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Jehmlich, Caroline
A1  - Hudson, Paul
A1  - Thieken, Annegret
T1  - Short contribution on adaptive behaviour of flood-prone companies
BT  - a pilot study of Dresden-Laubegast, Germany
JF  - Journal of Flood Risk Management
N2  - Integrated flood management strategies consider property-level precautionary measures as a vital part. Whereas this is a well-researched topic for residents, little is known about the adaptive behaviour of flood-prone companies although they often settle on the ground floor of buildings and are thus among the first affected by flooding. This pilot study analyses flood responses of 64 businesses in a district of the city of Dresden, Germany that experienced major flooding in 2002 and 2013. Using standardised survey data and accompanying qualitative interviews, the analyses revealed that the largest driver of adaptive behaviour is experiencing flood events. Intangible factors such as tradition and a sense of community play a role for the decision to stay in the area, while lacking ownership might hamper property-level adaptation. Further research is also needed to understand the role of insurance and governmental aid for recovery and adaptation of businesses.
KW  - adaptation
KW  - disaster risk reduction
KW  - integrated flood risk management
KW  - risk perception
Y1  - 2019
U6  - https://doi.org/10.1111/jfr3.12653
SN  - 1753-318X
VL  - 13
PB  - Wiley-Blackwell
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Koc, Gamze
A1  - Petrow, Theresia
A1  - Thieken, Annegret
T1  - Analysis of the most severe flood events in Turkey (1960-2014)
BT  - which triggering mechanisms and aggravating pathways can be identified?
JF  - Water / Molecular Diversity Preservation International (MDPI)
N2  - The most severe flood events in Turkey were determined for the period 1960-2014 by considering the number of fatalities, the number of affected people, and the total economic losses as indicators. The potential triggering mechanisms (i.e., atmospheric circulations and precipitation amounts) and aggravating pathways (i.e., topographic features, catchment size, land use types, and soil properties) of these 25 events were analyzed. On this basis, a new approach was developed to identify the main influencing factor per event and to provide additional information for determining the dominant flood occurrence pathways for severe floods. The events were then classified through hierarchical cluster analysis. As a result, six different clusters were found and characterized. Cluster 1 comprised flood events that were mainly influenced by drainage characteristics (e.g., catchment size and shape); Cluster 2 comprised events aggravated predominantly by urbanization; steep topography was identified to be the dominant factor for Cluster 3; extreme rainfall was determined as the main triggering factor for Cluster 4; saturated soil conditions were found to be the dominant factor for Cluster 5; and orographic effects of mountain ranges characterized Cluster 6. This study determined pathway patterns of the severe floods in Turkey with regard to their main causal or aggravating mechanisms. Accordingly, geomorphological properties are of major importance in large catchments in eastern and northeastern Anatolia. In addition, in small catchments, the share of urbanized area seems to be an important factor for the extent of flood impacts. This paper presents an outcome that could be used for future urban planning and flood risk prevention studies to understand the flood mechanisms in different regions of Turkey.
KW  - hierarchical clustering
KW  - Hess-Brezowsky Grosswetterlagen classification
KW  - ERA5
KW  - flood hazards
KW  - pathway
KW  - Turkey
Y1  - 2020
U6  - https://doi.org/10.3390/w12061562
SN  - 2073-4441
VL  - 12
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Kellermann, Patric
A1  - Schröter, Kai
A1  - Thieken, Annegret
A1  - Haubrock, Sören-Nils
A1  - Kreibich, Heidi
T1  - The object-specific flood damage database HOWAS 21
JF  - Natural hazards and earth system sciences
N2  - The Flood Damage Database HOWAS 21 contains object-specific flood damage data resulting from fluvial, pluvial and groundwater flooding. The datasets incorporate various variables of flood hazard, exposure, vulnerability and direct tangible damage at properties from several economic sectors. The main purpose of development of HOWAS 21 was to support forensic flood analysis and the derivation of flood damage models. HOWAS 21 was first developed for Germany and currently almost exclusively contains datasets from Germany. However, its scope has recently been enlarged with the aim to serve as an international flood damage database; e.g. its web application is now available in German and English. This paper presents the recent advancements of HOWAS 21 and highlights exemplary analyses to demonstrate the use of HOWAS 21 flood damage data. The data applications indicate a large potential of the database for fostering a better understanding and estimation of the consequences of flooding.
Y1  - 2020
U6  - https://doi.org/10.5194/nhess-20-2503-2020
SN  - 1561-8633
SN  - 1684-9981
VL  - 20
IS  - 9
SP  - 2503
EP  - 2519
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Pradhan, Prajal
A1  - Kropp, Jürgen
T1  - Interplay between diets, health, and climate change
JF  - Sustainability
N2  - The world is facing a triple burden of undernourishment, obesity, and environmental impacts from agriculture while nourishing its population. This burden makes sustainable nourishment of the growing population a global challenge. Addressing this challenge requires an understanding of the interplay between diets, health, and associated environmental impacts (e.g., climate change). For this, we identify 11 typical diets that represent dietary habits worldwide for the last five decades. Plant-source foods provide most of all three macronutrients (carbohydrates, protein, and fat) in developing countries. In contrast, animal-source foods provide a majority of protein and fat in developed ones. The identified diets deviate from the recommended healthy diet with either too much (e.g., red meat) or too little (e.g., fruits and vegetables) food and nutrition supply. The total calorie supplies are lower than required for two diets. Sugar consumption is higher than recommended for five diets. Three and five diets consist of larger-than-recommended carbohydrate and fat shares, respectively. Four diets with a large share of animal-source foods exceed the recommended value of red meat. Only two diets consist of at least 400 gm/cap/day of fruits and vegetables while accounting for food waste. Prevalence of undernourishment and underweight dominates in the diets with lower calories. In comparison, a higher prevalence of obesity is observed for diets with higher calories with high shares of sugar, fat, and animal-source foods. However, embodied emissions in the diets do not show a clear relation with calorie supplies and compositions. Two high-calorie diets embody more than 1.5 t CO<mml:semantics>2</mml:semantics>eq/cap/yr, and two low-calorie diets embody around 1 t CO<mml:semantics>2</mml:semantics>eq/cap/yr. Our analysis highlights that sustainable and healthy diets can serve the purposes of both nourishing the population and, at the same time, reducing the environmental impacts of agriculture.
KW  - dietary patterns
KW  - healthy diets
KW  - embodied emissions
KW  - diet shifts
KW  - sustainable diets
KW  - emission intensity
Y1  - 2020
U6  - https://doi.org/10.3390/su12093878
SN  - 2071-1050
VL  - 12
IS  - 9
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Vyse, Stuart Andrew
A1  - Semiromi, Majid Taie
A1  - Lischeid, Gunnar
A1  - Merz, Christoph
T1  - Characterizing hydrological processes within kettle holes using stable water isotopes in the Uckermark of northern Brandenburg, Germany
JF  - Hydrological Processes
N2  - Understanding the hydrologic connectivity between kettle holes and shallow groundwater, particularly in reaction to the highly variable local meteorological conditions, is of paramount importance for tracing water in a hydro(geo)logically complex landscape and thus for integrated water resource management. This article is aimed at identifying the dominant hydrological processes affecting the kettle holes' water balance and their interactions with the shallow groundwater domain in the Uckermark region, located in the north-east of Germany. For this reason, based on the stable isotopes of oxygen (delta O-18) and hydrogen (delta H-2), an isotopic mass balance model was employed to compute the evaporative loss of water from the kettle holes from February to August 2017. Results demonstrated that shallow groundwater inflow may play the pivotal role in the processes taking part in the hydrology of the kettle holes in the Uckermark region. Based on the calculated evaporation/inflow (E/I) ratios, most of the kettle holes (86.7%) were ascertained to have a partially open, flow-through-dominated system. Moreover, we identified an inverse correlation between E/I ratios and the altitudes of the kettle holes. The same holds for electrical conductivity (EC) and the altitudes of the kettle holes. In accordance with the findings obtained from this study, a conceptual model explaining the interaction between the shallow groundwater and the kettle holes of Uckermark was developed. The model exhibited that across the highest altitudes, the recharge kettle holes are dominant, where a lower ratio of E/I and a lower EC was detected. By contrast, the lowest topographical depressions represent the discharge kettle holes, where a higher ratio of E/I and EC could be identified. The kettle holes existing in between were categorized as flow-through kettle holes through which the recharge takes place from one side and discharge from the other side.
KW  - evaporation
KW  - groundwater inflow
KW  - kettle hole
KW  - stable water isotope
KW  - surface–groundwater interactions
Y1  - 2020
U6  - https://doi.org/10.1002/hyp.13699
SN  - 0885-6087
SN  - 1099-1085
VL  - 34
IS  - 8
SP  - 1868
EP  - 1887
PB  - Wiley
CY  - New York
ER  - 
TY  - JOUR
A1  - Smetanová, Anna
A1  - Müller, Anne
A1  - Zargar, Morteza
A1  - Suleiman, Mohamed A.
A1  - Gholami, Faraz Rabei
A1  - Mousavi, Maryam
T1  - Mesoscale mapping of sediment source hotspots for dam sediment management in data-sparse semi-arid catchments
JF  - Water
N2  - Land degradation and water availability in semi-arid regions are interdependent challenges for management that are influenced by climatic and anthropogenic changes. Erosion and high sediment loads in rivers cause reservoir siltation and decrease storage capacity, which pose risk on water security for citizens, agriculture, and industry. In regions where resources for management are limited, identifying spatial-temporal variability of sediment sources is crucial to decrease siltation. Despite widespread availability of rigorous methods, approaches simplifying spatial and temporal variability of erosion are often inappropriately applied to very data sparse semi-arid regions. In this work, we review existing approaches for mapping erosional hotspots, and provide an example of spatial-temporal mapping approach in two case study regions. The barriers limiting data availability and their effects on erosion mapping methods, their validation, and resulting prioritization of leverage management areas are discussed.
KW  - reservoir siltation
KW  - water security
KW  - water management
KW  - data sharing
KW  - spatial-temporal
KW  - erosion hotspots
KW  - mapping
KW  - global datasets
KW  - mesoscale
KW  - leverage areas
Y1  - 2020
U6  - https://doi.org/10.3390/w12020396
SN  - 2073-4441
VL  - 12
IS  - 2
SP  - 1
EP  - 24
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Mtilatila, Lucy Mphatso Ng'ombe
A1  - Bronstert, Axel
A1  - Shrestha, Pallav
A1  - Kadewere, Peter
A1  - Vormoor, Klaus Josef
T1  - Susceptibility of water resources and hydropower production to climate change in the tropics
BT  - the case of Lake Malawi and Shire River Basins, SE Africa
JF  - Hydrology : open access journal
N2  - The sensitivity of key hydrologic variables and hydropower generation to climate change in the Lake Malawi and Shire River basins is assessed. The study adapts the mesoscale Hydrological Model (mHM) which is applied separately in the Upper Lake Malawi and Shire River basins. A particular Lake Malawi model, which focuses on reservoir routing and lake water balance, has been developed and is interlinked between the two basins. Climate change projections from 20 Coordinated Regional Climate Downscaling Experiment (CORDEX) models for Africa based on two scenarios (RCP4.5 and RCP8.5) for the periods 2021-2050 and 2071-2100 are used. An annual temperature increase of 1 degrees C decreases mean lake level and outflow by 0.3 m and 17%, respectively, signifying the importance of intensified evaporation for Lake Malawi's water budget. Meanwhile, a +5% (-5%) deviation in annual rainfall changes mean lake level by +0.7 m (-0.6 m). The combined effects of temperature increase and rainfall decrease result in significantly lower flows in the Shire River. The hydrological river regime may change from perennial to seasonal with the combination of annual temperature increase and precipitation decrease beyond 1.5 degrees C (3.5 degrees C) and -20% (-15%). The study further projects a reduction in annual hydropower production between 1% (RCP8.5) and 2.5% (RCP4.5) during 2021-2050 and between 5% (RCP4.5) and 24% (RCP8.5) during 2071-2100. The results show that it is of great importance that a further development of hydro energy on the Shire River should take into account the effects of climate change, e.g., longer low flow periods and/or higher discharge fluctuations, and thus uncertainty in the amount of electricity produced.
KW  - Lake Malawi Basin
KW  - Shire River Basin
KW  - lake water balance
KW  - climate change impacts in the tropics
KW  - hydropower generation
KW  - response surface analysis
KW  - sensitivity analysis
Y1  - 2020
U6  - https://doi.org/10.3390/hydrology7030054
SN  - 2306-5338
VL  - 7
IS  - 3
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Rottler, Erwin
A1  - Francke, Till
A1  - Bürger, Gerd
A1  - Bronstert, Axel
T1  - Long-term changes in central European river discharge for 1869–2016
BT  - impact of changing snow covers, reservoir constructions and an intensified hydrological cycle
JF  - Hydrology and Earth System Sciences
N2  - Recent climatic changes have the potential to severely alter river runoff, particularly in snow-dominated river basins. Effects of changing snow covers superimpose with changes in precipitation and anthropogenic modifications of the watershed and river network. In the attempt to identify and disentangle long-term effects of different mechanisms, we employ a set of analytical tools to extract long-term changes in river runoff at high resolution. We combine quantile sampling with moving average trend statistics and empirical mode decomposition and apply these tools to discharge data recorded along rivers with nival, pluvial and mixed flow regimes as well as temperature and precipitation data covering the time frame 1869-2016. With a focus on central Europe, we analyse the long-term impact of snow cover and precipitation changes along with their interaction with reservoir constructions.

Our results show that runoff seasonality of snow-dominated rivers decreases. Runoff increases in winter and spring, while discharge decreases in summer and at the beginning of autumn. We attribute this redistribution of annual flow mainly to reservoir constructions in the Alpine ridge. During the course of the last century, large fractions of the Alpine rivers were dammed to produce hydropower. In recent decades, runoff changes induced by reservoir constructions seem to overlap with changes in snow cover. We suggest that Alpine signals propagate downstream and affect runoff far outside the Alpine area in river segments with mixed flow regimes. Furthermore, our results hint at more (intense) rain-fall in recent decades. Detected increases in high discharge can be traced back to corresponding changes in precipitation.
KW  - empirical mode decomposition
KW  - atmospheric blocking
KW  - heavy precipitation
KW  - streamflow trends
KW  - climate-change
KW  - rhine basin
KW  - time-series
KW  - events
KW  - Switzerland
KW  - variability
Y1  - 2020
U6  - https://doi.org/10.5194/hess-24-1721-2020
SN  - 1027-5606
SN  - 1607-7938
VL  - 24
IS  - 4
SP  - 1721
EP  - 1740
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Jing, Miao
A1  - Kumar, Rohini
A1  - Heße, Falk
A1  - Thober, Stephan
A1  - Rakovec, Oldrich
A1  - Samaniego, Luis
A1  - Attinger, Sabine
T1  - Assessing the response of groundwater quantity and travel time distribution to 1.5, 2, and 3 °C global warming in a mesoscale central German basin
JF  - Hydrology and Earth System Sciences
N2  - Groundwater is the biggest single source of high-quality freshwater worldwide, which is also continuously threatened by the changing climate. In this paper, we investigate the response of the regional groundwater system to climate change under three global warming levels (1.5, 2, and 3 ∘C) in a central German basin (Nägelstedt). This investigation is conducted by deploying an integrated modeling workflow that consists of a mesoscale hydrologic model (mHM) and a fully distributed groundwater model, OpenGeoSys (OGS). mHM is forced with climate simulations of five general circulation models under three representative concentration pathways. The diffuse recharges estimated by mHM are used as boundary forcings to the OGS groundwater model to compute changes in groundwater levels and travel time distributions. Simulation results indicate that groundwater recharges and levels are expected to increase slightly under future climate scenarios. Meanwhile, the mean travel time is expected to decrease compared to the historical average. However, the ensemble simulations do not all agree on the sign of relative change. Changes in mean travel time exhibit a larger variability than those in groundwater levels. The ensemble simulations do not show a systematic relationship between the projected change (in both groundwater levels and travel times) and the warming level, but they indicate an increased variability in projected changes with adjusting the enhanced warming level from 1.5 to 3 ∘C. Correspondingly, it is highly recommended to restrain the trend of global warming.
KW  - climate change impacts
KW  - hydrological models
KW  - coupled surface
KW  - water fluxes
KW  - catchment
KW  - recharge
KW  - dynamics
KW  - aquifer
KW  - flow
KW  - parameterization
Y1  - 2020
U6  - https://doi.org/10.5194/hess-24-1511-2020
SN  - 1607-7938
SN  - 1027-5606
VL  - 24
IS  - 3
SP  - 1511
EP  - 1526
PB  - Copernicus Publ.
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Schmidt, Lennart
A1  - Heße, Falk
A1  - Attinger, Sabine
A1  - Kumar, Rohini
T1  - Challenges in applying machine learning models for hydrological inference: a case study for flooding events across Germany
JF  - Water Resources Research
N2  - Machine learning (ML) algorithms are being increasingly used in Earth and Environmental modeling studies owing to the ever-increasing availability of diverse data sets and computational resources as well as advancement in ML algorithms. Despite advances in their predictive accuracy, the usefulness of ML algorithms for inference remains elusive. In this study, we employ two popular ML algorithms, artificial neural networks and random forest, to analyze a large data set of flood events across Germany with the goals to analyze their predictive accuracy and their usability to provide insights to hydrologic system functioning. The results of the ML algorithms are contrasted against a parametric approach based on multiple linear regression. For analysis, we employ a model-agnostic framework named Permuted Feature Importance to derive the influence of models' predictors. This allows us to compare the results of different algorithms for the first time in the context of hydrology. Our main findings are that (1) the ML models achieve higher prediction accuracy than linear regression, (2) the results reflect basic hydrological principles, but (3) further inference is hindered by the heterogeneity of results across algorithms. Thus, we conclude that the problem of equifinality as known from classical hydrological modeling also exists for ML and severely hampers its potential for inference. To account for the observed problems, we propose that when employing ML for inference, this should be made by using multiple algorithms and multiple methods, of which the latter should be embedded in a cross-validation routine.
KW  - machine learning
KW  - inference
KW  - floods
Y1  - 2019
VL  - 56
IS  - 5
PB  - John Wiley & Sons, Inc.
CY  - New Jersey
ER  - 
TY  - JOUR
A1  - Bilbao-Lasa, Peru
A1  - Jara Muñoz, Julius
A1  - Pedoja, Kevin
A1  - Álvarez, Irantzu
A1  - Aranburu, Arantza
A1  - Iriarte, Eneko
A1  - Galparsoro, Ibon
T1  - Submerged marine terraces identification and an approach for numerical modeling the sequence formation in the Bay of Biscay (Northeastern Iberian Peninsula)
JF  - Frontiers in Earth Science
N2  - Submerged sequences of marine terraces potentially provide crucial information of past sea-level positions. However, the distribution and characteristics of drowned marine terrace sequences are poorly known at a global scale. Using bathymetric data and novel mapping and modeling techniques, we studied a submerged sequence of marine terraces in the Bay of Biscay with the objective to identify the distribution and morphologies of submerged marine terraces and the timing and conditions that allowed their formation and preservation. To accomplish the objectives a high-resolution bathymetry (5 m) was analyzed using Geographic Information Systems and TerraceM(R). The successive submerged terraces were identified using a Surface Classification Model, which linearly combines the slope and the roughness of the surface to extract fossil sea-cliffs and fossil rocky shore platforms. For that purpose, contour and hillshaded maps were also analyzed. Then, shoreline angles, a geomorphic marker located at the intersection between the fossil sea-cliff and platform, were mapped analyzing swath profiles perpendicular to the isobaths. Most of the submerged strandlines are irregularly preserved throughout the continental shelf. In summary, 12 submerged terraces with their shoreline angles between approximately: -13 m (T1), -30 and -32 m (T2), -34 and 41 m (T3), -44 and -47 m (T4), -49 and 53 m (T5), -55 and 58 m (T6), -59 and 62 m (T7), -65 and 67 m (T8), -68 and 70 m (T9), -74 and -77 m (T10), -83 and -86 m (T11) and -89 and 92 m (T12). Nevertheless, the ones showing the best lateral continuity and preservation in the central part of the shelf are T3, T4, T5, T7, T8, and T10. The age of the terraces has been estimated using a landscape evolution model. To simulate the formation and preservation of submerged terraces three different scenarios: (i) 20-0 ka; (ii) 128-0 ka; and (iii) 128-20 ka, were compared. The best scenario for terrace generation was between 128 and 20 Ka, where T3, T5, and T7 could have been formed.
KW  - marine terrace
KW  - submerged sequence
KW  - digital bathymetric model
KW  - TerraceM
KW  - numerical modeling
KW  - Bay of Biscay
Y1  - 2020
U6  - https://doi.org/10.3389/feart.2020.00047
SN  - 2296-6463
VL  - 8
IS  - 47
SP  - 1
EP  - 20
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Metin, Ayse Duha
A1  - Dung, Nguyen Viet
A1  - Schröter, Kai
A1  - Vorogushyn, Sergiy
A1  - Guse, Björn
A1  - Kreibich, Heidi
A1  - Merz, Bruno
T1  - The role of spatial dependence for large-scale flood risk estimation
JF  - Natural hazards and earth system sciences
N2  - Flood risk assessments are typically based on scenarios which assume homogeneous return periods of flood peaks throughout the catchment. This assumption is unrealistic for real flood events and may bias risk estimates for specific return periods. We investigate how three assumptions about the spatial dependence affect risk estimates: (i) spatially homogeneous scenarios (complete dependence), (ii) spatially heterogeneous scenarios (modelled dependence) and (iii) spatially heterogeneous but uncorrelated scenarios (complete independence). To this end, the model chain RFM (regional flood model) is applied to the Elbe catchment in Germany, accounting for the spatio-temporal dynamics of all flood generation processes, from the rainfall through catchment and river system processes to damage mechanisms. Different assumptions about the spatial dependence do not influence the expected annual damage (EAD); however, they bias the risk curve, i.e. the cumulative distribution function of damage. The widespread assumption of complete dependence strongly overestimates flood damage of the order of 100% for return periods larger than approximately 200 years. On the other hand, for small and medium floods with return periods smaller than approximately 50 years, damage is underestimated. The overestimation aggravates when risk is estimated for larger areas. This study demonstrates the importance of representing the spatial dependence of flood peaks and damage for risk assessments.
Y1  - 2020
U6  - https://doi.org/10.5194/nhess-20-967-2020
SN  - 1561-8633
SN  - 1684-9981
VL  - 20
IS  - 4
SP  - 967
EP  - 979
PB  - European Geosciences Union (EGU) ; Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Ramachandran, Srikanthan
A1  - Rupakheti, Maheswar
A1  - Lawrence, Mark
T1  - Aerosol-induced atmospheric heating rate decreases over South and East Asia as a result of changing content and composition
JF  - Scientific reports
N2  - Aerosol emissions from human activities are extensive and changing rapidly over Asia. Model simulations and satellite observations indicate a dipole pattern in aerosol emissions and loading between South Asia and East Asia, two of the most heavily polluted regions of the world. We examine the previously unexplored diverging trends in the existing dipole pattern of aerosols between East and South Asia using the high quality, two-decade long ground-based time series of observations of aerosol properties from the Aerosol Robotic Network (AERONET), from satellites (Moderate Resolution Imaging Spectroradiometer (MODIS) and Ozone Monitoring Instrument (OMI)), and from model simulations (Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2). The data cover the period since 2001 for Kanpur (South Asia) and Beijing (East Asia), two locations taken as being broadly representative of the respective regions. Since 2010 a dipole in aerosol optical depth (AOD) is maintained, but the trend is reversed-the decrease in AOD over Beijing (East Asia) is rapid since 2010, being 17% less in current decade compared to first decade of twenty-first century, while the AOD over South Asia increased by 12% during the same period. Furthermore, we find that the aerosol composition is also changing over time. The single scattering albedo (SSA), a measure of aerosol's absorption capacity and related to aerosol composition, is slightly higher over Beijing than Kanpur, and has increased from 0.91 in 2002 to 0.93 in 2017 over Beijing and from 0.89 to 0.92 during the same period over Kanpur, confirming that aerosols in this region have on an average become more scattering in nature. These changes have led to a notable decrease in aerosol-induced atmospheric heating rate (HR) over both regions between the two decades, decreasing considerably more over East Asia (- 31%) than over South Asia (- 9%). The annual mean HR is lower now, it is still large (>= 0.6 K per day), which has significant climate implications. The seasonal trends in AOD, SSA and HR are more pronounced than their respective annual trends over both regions. The seasonal trends are caused mainly by the increase/decrease in anthropogenic aerosol emissions (sulfate, black carbon and organic carbon) while the natural aerosols (dust and sea salt) did not change significantly over South and East Asia during the last two decades. The MERRA-2 model is able to simulate the observed trends in AODs well but not the magnitude, while it also did not simulate the SSA values or trends well. These robust findings based on observations of key aerosol parameters and previously unrecognized diverging trends over South and East Asia need to be accounted for in current state-of-the-art climate models to ensure accurate quantification of the complex and evolving impact of aerosols on the regional climate over Asia.
Y1  - 2020
U6  - https://doi.org/10.1038/s41598-020-76936-z
SN  - 2045-2322
VL  - 10
IS  - 1
PB  - Macmillan Publishers Limited, part of Springer Nature
CY  - [London]
ER  - 
TY  - JOUR
A1  - Dietze, Elisabeth
A1  - Mangelsdorf, Kai
A1  - Andreev, Andrei
A1  - Karger, Cornelia
A1  - Schreuder, Laura T.
A1  - Hopmans, Ellen C.
A1  - Rach, Oliver
A1  - Sachse, Dirk
A1  - Wennrich, Volker
A1  - Herzschuh, Ulrike
T1  - Relationships between low-temperature fires, climate and vegetation during three late glacials and interglacials of the last 430 kyr in northeastern Siberia reconstructed from monosaccharide anhydrides in Lake El’gygytgyn sediments
JF  - Climate of the Past
N2  - Landscapes in high northern latitudes are assumed to be highly sensitive to future global change, but the rates and long-term trajectories of changes are rather uncertain. In the boreal zone, fires are an important factor in climate-vegetation interactions and biogeochemical cycles. Fire regimes are characterized by small, frequent, low-intensity fires within summergreen boreal forests dominated by larch, whereas evergreen boreal forests dominated by spruce and pine burn large areas less frequently but at higher intensities. Here, we explore the potential of the monosaccharide anhydrides (MA) levoglucosan, mannosan and galactosan to serve as proxies of low-intensity biomass burning in glacial-to-interglacial lake sediments from the high northern latitudes. We use sediments from Lake El'gygytgyn (cores PG 1351 and ICDP 5011-1), located in the far north-east of Russia, and study glacial and interglacial samples of the last 430 kyr (marine isotope stages 5e, 6, 7e, 8, 11c and 12) that had different climate and biome configurations. Combined with pollen and non-pollen palynomorph records from the same samples, we assess how far the modern relationships between fire, climate and vegetation persisted during the past, on orbital to centennial timescales. We find that MAs attached to particulates were well-preserved in up to 430 kyr old sediments with higher influxes from low-intensity biomass burning in interglacials compared to glacials. MA influxes significantly increase when summergreen boreal forest spreads closer to the lake, whereas they decrease when tundra-steppe environments and, especially, Sphagnum peatlands spread. This suggests that low-temperature fires are a typical characteristic of Siberian larch forests also on long timescales. The results also suggest that low-intensity fires would be reduced by vegetation shifts towards very dry environments due to reduced biomass availability, as well as by shifts towards peatlands, which limits fuel dryness. In addition, we observed very low MA ratios, which we interpret as high contributions of galactosan and mannosan from biomass sources other than those currently monitored, such as the moss-lichen mats in the understorey of the summergreen boreal forest. Overall, sedimentary MAs can provide a powerful proxy for fire regime reconstructions and extend our knowledge of long-term natural fire-climate-vegetation feedbacks in the high northern latitudes.
KW  - molecular tracers
KW  - organic aerosols
KW  - emission factors
KW  - carbonaceous aerosols
KW  - pollen records
KW  - core PG1351
KW  - biomass
KW  - holocene
KW  - levoglucosan
KW  - charcoal
Y1  - 2020
U6  - https://doi.org/10.5194/cp-16-799-2020
SN  - 1814-9332
SN  - 1814-9324
VL  - 16
IS  - 2
SP  - 788
EP  - 818
PB  - Copernicus Publications
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Liu, Sisi
A1  - Stoof-Leichsenring, Kathleen Rosemarie
A1  - Kruse, Stefan
A1  - Pestryakova, Luidmila Agafyevna
A1  - Herzschuh, Ulrike
T1  - Holocene vegetation and plant diversity changes in the north-eastern Siberian treeline region from pollen and sedimentary ancient DNA
JF  - Frontiers in Ecology and Evolution
N2  - Although sedimentary ancient DNA (sedaDNA) has been increasingly used to study paleoecological dynamics (Schulte et al., 2020), the approach has rarely been compared with the traditional method of pollen analysis for investigating past changes in the vegetation composition and diversity of Arctic treeline areas. Here, we provide a history of latitudinal floristic composition and species diversity based on a comparison ofsedaDNA and pollen data archived in three Siberian lake sediment cores spanning the mid-Holocene to the present (7.6-0 cal ka BP), from northern typical tundra to southern open larch forest in the Omoloy region. Our results show that thesedaDNA approach identifies more plant taxa found in the local vegetation communities, while the corresponding pollen analysis mainly captures the regional vegetation development and has its limitations for plant diversity reconstruction. Measures of alpha diversity were calculated based onsedaDNA data recovered from along a tundra to forest tundra to open larch forest gradient. Across all sites,sedaDNA archives provide a complementary record of the vegetation transition within each lake's catchment, tracking a distinct latitudinal vegetation type range from larch tree/alder shrub (open larch forest site) to dwarf shrub-steppe (forest tundra) to wet sedge tundra (typical tundra site). By contrast, the pollen data reveal an open landscape, which cannot distinguish the temporal changes in compositional vegetation for the open larch forest site and forest-tundra site. IncreasingLarixpollen percentages were recorded in the forest-tundra site in the last millenium although noLarixDNA was detected, suggesting that thesedaDNA approach performs better for tracking the local establishment ofLarix. Highest species richness and diversity are found in the mid-Holocene (before 4.4 ka) at the typical tundra site with a diverse range of vegetational habitats, while lowest species richness is recorded for the forest tundra where dwarf-willow habitats dominated the lake's catchment. During the late Holocene, strong declines in species richness and diversity are found at the typical tundra site with the vegetation changing to relatively simple communities. Nevertheless, plant species richness is mostly higher than at the forest-tundra site, which shows a slightly decreasing trend. Plant species richness at the open larch forest site fluctuates through time and is higher than the other sites since around 2.5 ka. Taken together, there is no evidence to suggest that the latitudinal gradients in species diversity changes are present at a millennial scale. Additionally, a weak correlation between the principal component analysis (PCA) site scores ofsedaDNA and species richness suggests that climate may not be a direct driver of species turnover within a lake's catchment. Our data suggest thatsedaDNA and pollen have different but complementary abilities for reconstructing past vegetation and species diversity along a latitude.
KW  - sedimentary ancient DNA
KW  - metabarcoding
KW  - pollen
KW  - Siberia
KW  - palaeovegetation
KW  - plant diversity
KW  - latitudinal gradient
Y1  - 2020
U6  - https://doi.org/10.3389/fevo.2020.560243
SN  - 2296-701X
VL  - 8
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Cao, Xianyong
A1  - Tian, Fang
A1  - Andreev, Andrei
A1  - Anderson, Patricia M.
A1  - Lozhkin, Anatoly V.
A1  - Bezrukova, Elena
A1  - Ni, Jian
A1  - Rudaya, Natalia
A1  - Stobbe, Astrid
A1  - Wieczorek, Mareike
A1  - Herzschuh, Ulrike
T1  - A taxonomically harmonized and temporally standardized fossil pollen dataset from Siberia covering the last 40 kyr
JF  - Earth System Science Data
N2  - Pollen records from Siberia are mostly absent in global or Northern Hemisphere synthesis works. Here we present a taxonomically harmonized and temporally standardized pollen dataset that was synthesized using 173 palynological records from Siberia and adjacent areas (northeastern Asia, 42-75 degrees N, 50-180 degrees E). Pollen data were taxonomically harmonized, i.e. the original 437 taxa were assigned to 106 combined pollen taxa. Age-depth models for all records were revised by applying a constant Bayesian age-depth modelling routine. The pollen dataset is available as count data and percentage data in a table format (taxa vs. samples), with age information for each sample. The dataset has relatively few sites covering the last glacial period between 40 and 11.5 ka (calibrated thousands of years before 1950 CE) particularly from the central and western part of the study area. In the Holocene period, the dataset has many sites from most of the area, with the exception of the central part of Siberia. Of the 173 pollen records, 81 % of pollen counts were downloaded from open databases (GPD, EPD, PANGAEA) and 10 % were contributions by the original data gatherers, while a few were digitized from publications. Most of the pollen records originate from peatlands (48 %) and lake sediments (33 %). Most of the records (83 %) have >= 3 dates, allowing the establishment of reliable chronologies. The dataset can be used for various purposes, including pollen data mapping (example maps for Larix at selected time slices are shown) as well as quantitative climate and vegetation reconstructions. The datasets for pollen counts and pollen percentages are available at https://doi.org/10.1594/PANGAEA.898616 (Cao et al., 2019a), also including the site information, data source, original publication, dating data, and the plant functional type for each pollen taxa.
KW  - Late Quaternary vegetation
KW  - Holocene environmental history
KW  - eastern continental Asia
KW  - plant macrofossil data
KW  - late pleistocene
KW  - paleoenvironmental records
KW  - Verkhoyansk mountains
KW  - climate dynamics
KW  - glacial maximum
KW  - Northern Asia
Y1  - 2020
U6  - https://doi.org/10.5194/essd-12-119-2020
SN  - 1866-3508
SN  - 1866-3516
VL  - 12
IS  - 1
SP  - 119
EP  - 135
PB  - Copernics Publications
CY  - Katlenburg-Lindau
ER  - 
TY  - JOUR
A1  - Vogel, Johannes
A1  - Paton, Eva Nora
A1  - Aich, Valentin
T1  - Seasonal ecosystem vulnerability to climatic anomalies in the Mediterranean
JF  - Biogeosciences
N2  - Mediterranean ecosystems are particularly vulnerable to climate change and the associated increase in climate anomalies. This study investigates extreme ecosystem responses evoked by climatic drivers in the Mediterranean Basin for the time span 1999–2019 with a specific focus on seasonal variations as the seasonal timing of climatic anomalies is considered essential for impact and vulnerability assessment. A bivariate vulnerability analysis is performed for each month of the year to quantify which combinations of the drivers temperature (obtained from ERA5-Land) and soil moisture (obtained from ESA CCI and ERA5-Land) lead to extreme reductions in ecosystem productivity using the fraction of absorbed photosynthetically active radiation (FAPAR; obtained from the Copernicus Global Land Service) as a proxy.

The bivariate analysis clearly showed that, in many cases, it is not just one but a combination of both drivers that causes ecosystem vulnerability. The overall pattern shows that Mediterranean ecosystems are prone to three soil moisture regimes during the yearly cycle: they are vulnerable to hot and dry conditions from May to July, to cold and dry conditions from August to October, and to cold conditions from November to April, illustrating the shift from a soil-moisture-limited regime in summer to an energy-limited regime in winter. In late spring, a month with significant vulnerability to hot conditions only often precedes the next stage of vulnerability to both hot and dry conditions, suggesting that high temperatures lead to critically low soil moisture levels with a certain time lag. In the eastern Mediterranean, the period of vulnerability to hot and dry conditions within the year is much longer than in the western Mediterranean. Our results show that it is crucial to account for both spatial and temporal variability to adequately assess ecosystem vulnerability. The seasonal vulnerability approach presented in this study helps to provide detailed insights regarding the specific phenological stage of the year in which ecosystem vulnerability to a certain climatic condition occurs.

How to cite. 
Vogel, J., Paton, E., and Aich, V.: Seasonal ecosystem vulnerability to climatic anomalies in the Mediterranean, Biogeosciences, 18, 5903–5927, https://doi.org/10.5194/bg-18-5903-2021, 2021.
Y1  - 2021
U6  - https://doi.org/10.5194/bg-18-5903-2021
SN  - 1726-4189
VL  - 18
SP  - 5903
EP  - 5927
PB  - Copernicus
CY  - Göttingen
ET  - 22
ER  - 
TY  - JOUR
A1  - Vogel, Johannes
A1  - Rivoire, Pauline
A1  - Deidda, Cristina
A1  - Rahimi, Leila
A1  - Sauter, Christoph A.
A1  - Tschumi, Elisabeth
A1  - van der Wiel, Karin
A1  - Zhang, Tianyi
A1  - Zscheischler, Jakob
T1  - Identifying meteorological drivers of extreme impacts
BT  - an application to simulated crop yields
JF  - Earth System Dynamics
N2  - Compound weather events may lead to extreme impacts that can affect many aspects of society including agriculture. Identifying the underlying mechanisms that cause extreme impacts, such as crop failure, is of crucial importance to improve their understanding and forecasting. In this study, we investigate whether key meteorological drivers of extreme impacts can be identified using the least absolute shrinkage and selection operator (LASSO) in a model environment, a method that allows for automated variable selection and is able to handle collinearity between variables. As an example of an extreme impact, we investigate crop failure using annual wheat yield as simulated by the Agricultural Production Systems sIMulator (APSIM) crop model driven by 1600 years of daily weather data from a global climate model (EC-Earth) under present-day conditions for the Northern Hemisphere. We then apply LASSO logistic regression to determine which weather conditions during the growing season lead to crop failure. We obtain good model performance in central Europe and the eastern half of the United States, while crop failure years in regions in Asia and the western half of the United States are less accurately predicted. Model performance correlates strongly with annual mean and variability of crop yields; that is, model performance is highest in regions with relatively large annual crop yield mean and variability. Overall, for nearly all grid points, the inclusion of temperature, precipitation and vapour pressure deficit is key to predict crop failure. In addition, meteorological predictors during all seasons are required for a good prediction. These results illustrate the omnipresence of compounding effects of both meteorological drivers and different periods of the growing season for creating crop failure events. Especially vapour pressure deficit and climate extreme indicators such as diurnal temperature range and the number of frost days are selected by the statistical model as relevant predictors for crop failure at most grid points, underlining their overarching relevance. We conclude that the LASSO regression model is a useful tool to automatically detect compound drivers of extreme impacts and could be applied to other weather impacts such as wildfires or floods. As the detected relationships are of purely correlative nature, more detailed analyses are required to establish the causal structure between drivers and impacts.
Y1  - 2020
U6  - https://doi.org/10.5194/esd-12-151-2021
SN  - 2190-4987
SN  - 2190-4979
VL  - 12
SP  - 151
EP  - 172
ER  - 
TY  - JOUR
A1  - Natho, Stephanie
T1  - How Flood Hazard Maps Improve the Understanding of Ecologically Active Floodplains
JF  - Water / Molecular Diversity Preservation International (MDPI)
N2  - Floodplains are threatened ecosystems and are not only ecologically meaningful but also important for humans by creating multiple benefits. Many underlying functions, like nutrient retention, carbon sequestration or water regulation, strongly depend on regular inundation. So far, these are approached on the basis of what are called ‘active floodplains’. Active floodplains, defined as statistically inundated once every 100 years, represent less than 10% of a floodplain’s original size. Still, should this remaining area be considered as one homogenous surface in terms of floodplain function, or are there any alternative approaches to quantify ecologically active floodplains? With the European Flood Hazard Maps, the extent of not only medium floods (T-medium) but also frequent floods (T-frequent) needs to be modelled by all member states of the European Union. For large German rivers, both scenarios were compared to quantify the extent, as well as selected indicators for naturalness derived from inundation. It is assumed that the more naturalness there is, the more inundation and the better the functioning. Real inundation was quantified using measured discharges from relevant gauges over the past 20 years. As a result, land uses indicating strong human impacts changed significantly from T-frequent to T-medium floodplains. Furthermore, the extent, water depth and water volume stored in the T-frequent and T-medium floodplains is significantly different. Even T-frequent floodplains experienced inundation for only half of the considered gauges during the past 20 years. This study gives evidence for considering regulation functions on the basis of ecologically active floodplains, meaning in floodplains with more frequent inundation that T-medium floodplains delineate.
KW  - active floodplain
KW  - frequent flood
KW  - flood hazard map
KW  - inundation
KW  - land use
Y1  - 2021
U6  - https://doi.org/10.3390/w13070937
SN  - 2073-4441
VL  - 13
IS  - 7
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Wehrhan, Marc
A1  - Sommer, Michael
T1  - A parsimonious approach to estimate soil organic carbon applying Unmanned Aerial System (UAS) multispectral imagery and the topographic position index in a heterogeneous soil landscape
JF  - Remote sensing / Molecular Diversity Preservation International (MDPI)
N2  - Remote sensing plays an increasingly key role in the determination of soil organic carbon (SOC) stored in agriculturally managed topsoils at the regional and field scales. Contemporary Unmanned Aerial Systems (UAS) carrying low-cost and lightweight multispectral sensors provide high spatial resolution imagery (<10 cm). These capabilities allow integrate of UAS-derived soil data and maps into digitalized workflows for sustainable agriculture. However, the common situation of scarce soil data at field scale might be an obstacle for accurate digital soil mapping. In our case study we tested a fixed-wing UAS equipped with visible and near infrared (VIS-NIR) sensors to estimate topsoil SOC distribution at two fields under the constraint of limited sampling points, which were selected by pedological knowledge. They represent all releva nt soil types along an erosion-deposition gradient; hence, the full feature space in terms of topsoils' SOC status. We included the Topographic Position Index (TPI) as a co-variate for SOC prediction. Our study was performed in a soil landscape of hummocky ground moraines, which represent a significant of global arable land. Herein, small scale soil variability is mainly driven by tillage erosion which, in turn, is strongly dependent on topography. Relationships between SOC, TPI and spectral information were tested by Multiple Linear Regression (MLR) using: (i) single field data (local approach) and (ii) data from both fields (pooled approach). The highest prediction performance determined by a leave-one-out-cross-validation (LOOCV) was obtained for the models using the reflectance at 570 nm in conjunction with the TPI as explanatory variables for the local approach (coefficient of determination (R-2) = 0.91; root mean square error (RMSE) = 0.11% and R-2 = 0.48; RMSE = 0.33, respectively). The local MLR models developed with both reflectance and TPI using values from all points showed high correlations and low prediction errors for SOC content (R-2 = 0.88, RMSE = 0.07%; R-2 = 0.79, RMSE = 0.06%, respectively). The comparison with an enlarged dataset consisting of all points from both fields (pooled approach) showed no improvement of the prediction accuracy but yielded decreased prediction errors. Lastly, the local MLR models were applied to the data of the respective other field to evaluate the cross-field prediction ability. The spatial SOC pattern generally remains unaffected on both fields; differences, however, occur concerning the predicted SOC level. Our results indicate a high potential of the combination of UAS-based remote sensing and environmental covariates, such as terrain attributes, for the prediction of topsoil SOC content at the field scale. The temporal flexibility of UAS offer the opportunity to optimize flight conditions including weather and soil surface status (plant cover or residuals, moisture and roughness) which, otherwise, might obscure the relationship between spectral data and SOC content. Pedologically targeted selection of soil samples for model development appears to be the key for an efficient and effective prediction even with a small dataset.
KW  - Unmanned Aerial System (UAS)
KW  - multispectral
KW  - Topographic Position Index
KW  - (TPI)
KW  - Multiple Linear Regression (MLR)
KW  - soil organic carbon (SOC)
KW  - agriculture
KW  - erosion
KW  - soil landscape
KW  - hummocky ground moraine
Y1  - 2021
U6  - https://doi.org/10.3390/rs13183557
SN  - 2072-4292
VL  - 13
IS  - 18
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Paton, Eva
A1  - Vogel, Johannes Joscha
A1  - Kluge, Björn
A1  - Nehls, Thomas
T1  - Ausmaß, Trend und Extrema von Dürren im urbanen Raum
T1  - Extent, trend and extremes of droughts in urban areas
JF  - Hydrologie und Wasserbewirtschaftung
N2  - Summers are currently perceived to be getting longer, hotter and more extreme - and this impression is reinforced in urban areas by the occurrence of heat island effects in densely built-up areas. To assess the real extent of increasing drought occurrences in German cities, a DWD data set of 31 urban climate stations for the period 1950 to 2019 was analysed using the standardised precipitation index (SPI) with regard to meteorological drought lengths, drought extrema, heat waves and compound events in the form of simultaneously occurring heat waves and drought months. The analysis shows a large degree of heterogeneity within Germany: a severe drought occurred in most cities in 2018, while the year 2018 was among the three years with the longest droughts (since 1950) for only one third of the cities. Some southern and central German cities show a statistically significant increase in drought months per decade since 1950, other cities, mostly in the north and northwest, only show an increase in the past two decades or even no trend at all. The compound analysis of simultaneously occurring heat and drought months shows a strong increase at most stations in the last two decades, whereby the two components are responsible with a very different proportion regionally for the increase in compound events.
N2  - In der derzeitigen Wahrnehmung werden die Sommer dürrer, heißer und extremer – dieser Eindruck verstärkt sich im urbanen Raum durch das Auftreten von Hitzeinseleffekten in dicht bebauten Gebieten. Um das wirkliche Ausmaß der Dürre bewerten zu können, wurden Zeitreihendaten von 31 urbanen Klimastationen (DWD) für den Zeitraum 1950 bis 2019 mittels des standardisierten Niederschlagsindex (SPI) bezüglich Dürrelängen, Dürreextrema, Hitzewellen und gleichzeitig auftretenden Hitze- und Dürremonaten ausgewertet.
Die Analyse zeigt eine große Heterogenität innerhalb von Deutschland: In den meisten Städten trat 2018 eine lange Dürre von einer durchschnittlichen Dauer von 6 Monaten auf, gleichzeitig gehörte das Jahr 2018 nur bei einem Drittel der Städte zu den drei Jahren mit den längsten Dürren seit 1950. Bei den meisten betrachteten Stationen traten die längsten Dürren in den Jahren 1953, 1971 und 1976 auf. Bei einigen südlichen und mitteldeutschen Städten kann man eine statistisch signifikante Zunahme der Anzahl der Dürremonate pro Dekade seit 1950 verzeichnen. Andere Städte, eher im Norden und Nordwesten gelegen, zeigen nur in den letzten zwei Dekaden eine Zunahme oder gar keinen Trend. Die Compoundanalyse von gleichzeitig auftretenden Hitze- und Dürremonaten zeigt bei den meisten Stationen eine starke Zunahme innerhalb der letzten zwei Dekaden, wobei die beiden Komponenten regional mit einem sehr unterschiedlichen Anteil zur Zunahme der Compoundereignisse beitragen.
KW  - meteorological droughts
KW  - heat waves
KW  - compound events
KW  - standardised
KW  - precipitation index (SPI)
KW  - urban hydrology
KW  - meteorologische Dürren
KW  - Hitzewellen
KW  - Compoundereignisse
KW  - standardisierter Niederschlagsindex (SPI
KW  - urbane Hydrologie
Y1  - 2021
U6  - https://doi.org/10.5675/HyWa_2021.1_1
SN  - 1439-1783
SN  - 2749-859X
VL  - 65
IS  - 1
SP  - 5
EP  - 16
PB  - Bundesanstalt für Gewässerkunde
CY  - Koblenz
ER  - 
TY  - JOUR
A1  - Susman, Roni
A1  - Gütte, Annelie Maja
A1  - Weith, Thomas
T1  - Drivers of land use conflicts in infrastructural mega projects in coastal areas
BT  - a case study of Patimban Seaport, Indonesia
JF  - Land : open access journal
N2  - Coastal areas are particularly sensitive because they are complex, and related land use conflicts are more intense than those in noncoastal areas. In addition to representing a unique encounter of natural and socioeconomic factors, coastal areas have become paradigms of progressive urbanisation and economic development. Our study of the infrastructural mega project of Patimban Seaport in Indonesia explores the factors driving land use changes and the subsequent land use conflicts emerging from large-scale land transformation in the course of seaport development and mega project governance. We utilised interviews and questionnaires to investigate institutional aspects and conflict drivers. Specifically, we retrace and investigate the mechanisms guiding how mega project governance, land use planning, and actual land use interact. Therefore, we observe and analyse where land use conflicts emerge and the roles that a lack of stakeholder interest involvement and tenure-responsive planning take in this process. Our findings reflect how mismanagement and inadequate planning processes lead to market failure, land abandonment and dereliction and how they overburden local communities with the costs of mega projects. Enforcing a stronger coherence between land use planning, participation and land tenure within the land governance process in coastal land use development at all levels and raising the capacity of stakeholders to interfere with governance and planning processes will reduce conflicts and lead to sustainable coastal development in Indonesia.
KW  - infrastructural mega projects
KW  - land use conflicts
KW  - land tenure
KW  - land use
KW  - planning
KW  - Patimban Seaport
Y1  - 2021
U6  - https://doi.org/10.3390/land10060615
SN  - 2073-445X
VL  - 10
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Fischer, Melanie
A1  - Korup, Oliver
A1  - Veh, Georg
A1  - Walz, Ariane
T1  - Controls of outbursts of moraine-dammed lakes in the greater Himalayan region
JF  - The Cryosphere
N2  - Glacial lakes in the Hindu Kush–Karakoram–Himalayas–Nyainqentanglha (HKKHN) region have grown rapidly in number and area in past decades, and some dozens have drained in catastrophic glacial lake outburst floods (GLOFs). Estimating regional susceptibility of glacial lakes has largely relied on qualitative assessments by experts, thus motivating a more systematic and quantitative appraisal. Before the backdrop of current climate-change projections and the potential of elevation-dependent warming, an objective and regionally consistent assessment is urgently needed. We use an inventory of 3390 moraine-dammed lakes and their documented outburst history in the past four decades to test whether elevation, lake area and its rate of change, glacier-mass balance, and monsoonality are useful inputs to a probabilistic classification model. We implement these candidate predictors in four Bayesian multi-level logistic regression models to estimate the posterior susceptibility to GLOFs. We find that mostly larger lakes have been more prone to GLOFs in the past four decades regardless of the elevation band in which they occurred. We also find that including the regional average glacier-mass balance improves the model classification. In contrast, changes in lake area and monsoonality play ambiguous roles. Our study provides first quantitative evidence that GLOF susceptibility in the HKKHN scales with lake area, though less so with its dynamics. Our probabilistic prognoses offer improvement compared to a random classification based on average GLOF frequency. Yet they also reveal some major uncertainties that have remained largely unquantified previously and that challenge the applicability of single models. Ensembles of multiple models could be a viable alternative for more accurately classifying the susceptibility of moraine-dammed lakes to GLOFs.
Y1  - 2020
U6  - https://doi.org/10.5194/tc-15-4145-2021
SN  - 1994-0416
VL  - 15
PB  - Copernicus Publications
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Macdonald, Elena
A1  - Otero, Noelia
A1  - Butler, Tim
T1  - A comparison of long-term trends in observations and emission inventories of NOx
JF  - Atmospheric chemistry and physics / European Geosciences Union
N2  - Air pollution is a pressing issue that is associated with adverse effects on human health, ecosystems, and climate. Despite many years of effort to improve air quality, nitrogen dioxide (NO2) limit values are still regularly exceeded in Europe, particularly in cities and along streets. This study explores how concentrations of nitrogen oxides (NOx = NO + NO2) in European urban areas have changed over the last decades and how this relates to changes in emissions. To do so, the incremental approach was used, comparing urban increments (i.e. urban background minus rural concentrations) to total emissions, and roadside increments (i.e. urban roadside concentrations minus urban background concentrations) to traffic emissions. In total, nine European cities were assessed. The study revealed that potentially confounding factors like the impact of urban pollution at rural monitoring sites through atmospheric transport are generally negligible for NOx. The approach proves therefore particularly useful for this pollutant. The estimated urban increments all showed downward trends, and for the majority of the cities the trends aligned well with the total emissions. However, it was found that factors like a very densely populated surrounding or local emission sources in the rural area such as shipping traffic on inland waterways restrict the application of the approach for some cities. The roadside increments showed an overall very diverse picture in their absolute values and trends and also in their relation to traffic emissions. This variability and the discrepancies between roadside increments and emissions could be attributed to a combination of local influencing factors at the street level and different aspects introducing inaccuracies to the trends of the emis-sion inventories used, including deficient emission factors. Applying the incremental approach was evaluated as useful for long-term pan-European studies, but at the same time it was found to be restricted to certain regions and cities due to data availability issues. The results also highlight that using emission inventories for the prediction of future health impacts and compliance with limit values needs to consider the distinct variability in the concentrations not only across but also within cities.
Y1  - 2021
U6  - https://doi.org/10.5194/acp-21-4007-2021
SN  - 1680-7316
SN  - 1680-7324
VL  - 21
IS  - 5
SP  - 4007
EP  - 4023
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Rainer, Edda M.
A1  - Seppey, Christophe Victor William
A1  - Hammer, Caroline
A1  - Svenning, Mette M.
A1  - Tveit, Alexander Tosdal
T1  - The influence of above-ground herbivory on the response of Arctic soil methanotrophs to increasing CH4 concentrations and temperatures
JF  - Microorganisms : open access journal
N2  - Rising temperatures in the Arctic affect soil microorganisms, herbivores, and peatland vegetation, thus directly and indirectly influencing microbial CH4 production. It is not currently known how methanotrophs in Arctic peat respond to combined changes in temperature, CH4 concentration, and vegetation. We studied methanotroph responses to temperature and CH4 concentration in peat exposed to herbivory and protected by exclosures. The methanotroph activity was assessed by CH4 oxidation rate measurements using peat soil microcosms and a pure culture of Methylobacter tundripaludum SV96, qPCR, and sequencing of pmoA transcripts. Elevated CH4 concentrations led to higher CH4 oxidation rates both in grazed and exclosed peat soils, but the strongest response was observed in grazed peat soils. Furthermore, the relative transcriptional activities of different methanotroph community members were affected by the CH4 concentrations. While transcriptional responses to low CH4 concentrations were more prevalent in grazed peat soils, responses to high CH4 concentrations were more prevalent in exclosed peat soils. We observed no significant methanotroph responses to increasing temperatures. We conclude that methanotroph communities in these peat soils respond to changes in the CH4 concentration depending on their previous exposure to grazing. This "conditioning " influences which strains will thrive and, therefore, determines the function of the methanotroph community.
KW  - methanotroph
KW  - methane oxidation
KW  - pmoA amplicon sequencing
KW  - Methylobacter
KW  - grazing pressure
KW  - peat soil microcosms
KW  - temperature
KW  - Arctic
Y1  - 2021
U6  - https://doi.org/10.3390/microorganisms9102080
SN  - 2076-2607
VL  - 9
IS  - 10
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Madruga de Brito, Mariana
A1  - Otto, Danny
A1  - Kuhlicke, Christian
T1  - Tracking topics and frames regarding sustainability transformations during the onset of the COVID-19 crisis
JF  - Sustainability / Multidisciplinary Digital Publishing Institute (MDPI)
N2  - Many researchers and politicians believe that the COVID-19 crisis may have opened a "window of opportunity " to spur sustainability transformations. Still, evidence for such a dynamic is currently lacking. Here, we propose the linkage of "big data " and "thick data " methods for monitoring debates on transformation processes by following the COVID-19 discourse on ecological sustainability in Germany. We analysed variations in the topics discussed by applying text mining techniques to a corpus with 84,500 newspaper articles published during the first COVID-19 wave. This allowed us to attain a unique and previously inaccessible "bird's eye view " of how these topics evolved. To deepen our understanding of prominent frames, a qualitative content analysis was undertaken. Furthermore, we investigated public awareness by analysing online search behaviour. The findings show an underrepresentation of sustainability topics in the German news during the early stages of the crisis. Similarly, public awareness regarding climate change was found to be reduced. Nevertheless, by examining the newspaper data in detail, we found that the pandemic is often seen as a chance for sustainability transformations-but not without a set of challenges. Our mixed-methods approach enabled us to bridge knowledge gaps between qualitative and quantitative research by "thickening " and providing context to data-driven analyses. By monitoring whether or not the current crisis is seen as a chance for sustainability transformations, we provide insights for environmental policy in times of crisis.
KW  - frames
KW  - SDG
KW  - green deal
KW  - content analysis
KW  - natural language processing
KW  - NLP
Y1  - 2021
U6  - https://doi.org/10.3390/su131911095
SN  - 2071-1050
VL  - 13
IS  - 19
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Lange, Bastian
A1  - Bürkner, Hans-Joachim
T1  - Ambiguous avant-gardes and their geographies
BT  - on blank spots of the postgrowth debate
JF  - Die Erde : journal of the Geographical Society of Berlin ; Zeitschrift der Gesellschaft für Erdkunde zu Berlin
N2  - In the following article, the focus is on the transformative potentials created by so-called persistence avant-gardes and prevention innovators. The text extends Bluhdorn's guiding concept of narratives of hope (Bluhdorn 2017; Bluhdorn and Butzlaff 2019) by considering those groups that are marginalized within debates on socio-ecological transformation. With a closer look at the narratives of prevention and blockade that these actors engage, the ambiguous nature of postgrowth avant-gardes is carved out. Their discursive, argumentative, and effective inhibition of transitory policies is interpreted as a pro-active potential, rather than a mere obstacle to socio-ecological transformation. Adding a geographical perspective, the paper pleads for a more precise theoretical penetration of the ambivalent figure of avantgardes when analyzing processes of local and regional postgrowth.
N2  - Mit dem Beitrag richten wir den Fokus auf transformative Potenziale, die von sogenannten Beharrungsavantgar-den  und  Präventionsinnovatoren  ausgehen.  Der  Text  erweitert  Blühdorns  Leitkonzept  der  Hoffnungsnarrative  (Blühdorn 2017; Blühdorn and Butzlaff 2019), indem er jene Gruppen in den Blick nimmt, die in den Debatten um die sozial-ökologische Transformation marginalisiert werden. Mit einem genaueren Blick auf die Präventions- und Blockade-Narrative dieser Akteure wird die Mehrdeutigkeit der Postwachstumsavantgarden herausgear-beitet. Ihre diskursive, argumentative und effektive Verhinderung transitorischer Politiken wird als proaktives Potenzial und nicht als bloßes Hindernis für eine sozial-ökologische Transformation interpretiert. Unter Hinzu-nahme  einer  geographischen  Perspektive  plädiert  der  Beitrag  für  eine  präzisere  theoretische  Durchdringung  der ambivalenten Figur der Avantgarden bei der Analyse lokaler und regionaler Postwachstumsvorgänge.
KW  - alternative economies
KW  - transformative policies
KW  - change agents
KW  - postgrowth
KW  - regional development
KW  - East Germany
Y1  - 2021
U6  - https://doi.org/10.12854/erde-2021-566
SN  - 0013-9998
VL  - 152
IS  - 4
SP  - 273
EP  - 287
PB  - Gesellschaft für Erdkunde
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Wehrhan, Marc
A1  - Puppe, Daniel
A1  - Kaczorek, Danuta
A1  - Sommer, Michael
T1  - Spatial patterns of aboveground phytogenic Si stocks in a grass-dominated catchment
BT  - results from UAS-based high-resolution remote sensing
JF  - Biogeosciences : BG
N2  - Various studies have been performed to quantify silicon (Si) stocks in plant biomass and related Si fluxes in terrestrial biogeosystems. Most studies are deliberately designed on the plot scale to ensure low heterogeneity in soils and plant composition, hence similar environmental conditions. Due to the immanent spatial soil variability, the transferability of results to larger areas, such as catchments, is therefore limited. However, the emergence of new technical features and increasing knowledge on details in Si cycling lead to a more complex picture at landscape and catchment scales. Dynamic and static soil properties change along the soil continuum and might influence not only the species composition of natural vegetation but also its biomass distribution and related Si stocks. Maximum likelihood (ML) classification was applied to multispectral imagery captured by an unmanned aerial system (UAS) aiming at the identification of land cover classes (LCCs). Subsequently, the normalized difference vegetation index (NDVI) and ground-based measurements of biomass were used to quantify aboveground Si stocks in two Si-accumulating plants (Calamagrostis epige-jos and Phragmites australis) in a heterogeneous catchment and related corresponding spatial patterns of these stocks to soil properties. We found aboveground Si stocks of C. epige-jos and P. australis to be surprisingly high (maxima of Si stocks reach values up to 98 g Sim(-2)), i.e. comparable to or markedly exceeding reported values for the Si storage in aboveground vegetation of various terrestrial ecosystems. We further found spatial patterns of plant aboveground Si stocks to reflect spatial heterogeneities in soil properties. From our results, we concluded that (i) aboveground biomass of plants seems to be the main factor of corresponding phytogenic Si stock quantities, and (ii) a detection of biomass heterogeneities via UAS-based remote sensing represents a promising tool for the quantification of lifelike phytogenic Si pools at landscape scales.
Y1  - 2021
U6  - https://doi.org/10.5194/bg-18-5163-2021
SN  - 1726-4170
SN  - 1726-4189
VL  - 18
IS  - 18
SP  - 5163
EP  - 5183
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Soergel, Bjoern
A1  - Kriegler, Elmar
A1  - Bodirsky, Benjamin Leon
A1  - Bauer, Nico
A1  - Leimbach, Marian
A1  - Popp, Alexander
T1  - Combining ambitious climate policies with efforts to eradicate poverty
JF  - Nature Communications
N2  - Climate change threatens to undermine efforts to eradicate extreme poverty. However, climate policies could impose a financial burden on the global poor through increased energy and food prices. Here, we project poverty rates until 2050 and assess how they are influenced by mitigation policies consistent with the 1.5 degrees C target. A continuation of historical trends will leave 350 million people globally in extreme poverty by 2030. Without progressive redistribution, climate policies would push an additional 50 million people into poverty. However, redistributing the national carbon pricing revenues domestically as an equal-per-capita climate dividend compensates this policy side effect, even leading to a small net reduction of the global poverty headcount (-6 million). An additional international climate finance scheme enables a substantial poverty reduction globally and also in Sub-Saharan Africa. Combining national redistribution with international climate finance thus provides an important entry point to climate policy in developing countries. Ambitious climate policies can negatively impact the global poor by affecting income, food and energy prices. Here, the authors quantify this effect, and show that it can be compensated by national redistribution of the carbon pricing revenues in combination with international climate finance.
Y1  - 2021
U6  - https://doi.org/10.1038/s41467-021-22315-9
SN  - 2041-1723
VL  - 12
PB  - Nature Publishing Group
CY  - London
ER  - 
TY  - JOUR
A1  - Schaller, Jörg
A1  - Scherwietes, Eric
A1  - Gerber, Lukas
A1  - Vaidya, Shrijana
A1  - Kaczorek, Danuta
A1  - Pausch, Johanna
A1  - Barkusky, Dietmar
A1  - Sommer, Michael
A1  - Hoffmann, Mathias
T1  - Silica fertilization improved wheat performance and increased phosphorus concentrations during drought at the field scale
JF  - Scientific reports
N2  - Drought and the availability of mineable phosphorus minerals used for fertilization are two of the important issues agriculture is facing in the future. High phosphorus availability in soils is necessary to maintain high agricultural yields. Drought is one of the major threats for terrestrial ecosystem performance and crop production in future. Among the measures proposed to cope with the upcoming challenges of intensifying drought stress and to decrease the need for phosphorus fertilizer application is the fertilization with silica (Si). Here we tested the importance of soil Si fertilization on wheat phosphorus concentration as well as wheat performance during drought at the field scale. Our data clearly showed a higher soil moisture for the Si fertilized plots. This higher soil moisture contributes to a better plant performance in terms of higher photosynthetic activity and later senescence as well as faster stomata responses ensuring higher productivity during drought periods. The plant phosphorus concentration was also higher in Si fertilized compared to control plots. Overall, Si fertilization or management of the soil Si pools seem to be a promising tool to maintain crop production under predicted longer and more serve droughts in the future and reduces phosphorus fertilizer requirements.
Y1  - 2021
U6  - https://doi.org/10.1038/s41598-021-00464-7
SN  - 2045-2322
VL  - 11
IS  - 1
PB  - Macmillan Publishers Limited, part of Springer Nature
CY  - [London]
ER  - 
TY  - JOUR
A1  - Samprogna Mohor, Guilherme
A1  - Thieken, Annegret
A1  - Korup, Oliver
T1  - Residential flood loss estimated from Bayesian multilevel models
JF  - Natural Hazards and Earth System Sciences
N2  - Models for the predictions of monetary losses from floods mainly blend data deemed to represent a single flood type and region. Moreover, these approaches largely ignore indicators of preparedness and how predictors may vary between regions and events, challenging the transferability of flood loss models. We use a flood loss database of 1812 German flood-affected households to explore how Bayesian multilevel models can estimate normalised flood damage stratified by event, region, or flood process type. Multilevel models acknowledge natural groups in the data and allow each group to learn from others. We obtain posterior estimates that differ between flood types, with credibly varying influences of water depth, contamination, duration, implementation of property-level precautionary measures, insurance, and previous flood experience; these influences overlap across most events or regions, however. We infer that the underlying damaging processes of distinct flood types deserve further attention. Each reported flood loss and affected region involved mixed flood types, likely explaining the uncertainty in the coefficients. Our results emphasise the need to consider flood types as an important step towards applying flood loss models elsewhere. We argue that failing to do so may unduly generalise the model and systematically bias loss estimations from empirical data.
KW  - damage
KW  - insurance
KW  - Germany
KW  - transferability
KW  - preparedness
KW  - recovery
Y1  - 2020
U6  - https://doi.org/10.5194/nhess-21-1599-2021
SN  - 2195-9269
VL  - 21
SP  - 1599
EP  - 1614
PB  - European Geophysical Society
CY  - Katlenburg-Lindau
ER  - 
TY  - JOUR
A1  - Goetz, Jason
A1  - Kohrs, Robin
A1  - Parra Hormazábal, Eric
A1  - Bustos Morales, Manuel
A1  - Araneda Riquelme, María Belén
A1  - Henríquez Ruiz, Cristian
A1  - Brenning, Alexander
T1  - Optimizing and validating the Gravitational Process Path model for regional debris-flow runout modelling
JF  - Natural hazards and earth system sciences : NHESS / European Geophysical Society
N2  - Knowing the source and runout of debris flows can help in planning strategies aimed at mitigating these hazards. Our research in this paper focuses on developing a novel approach for optimizing runout models for regional susceptibility modelling, with a case study in the upper Maipo River basin in the Andes of Santiago, Chile. We propose a two-stage optimization approach for automatically selecting parameters for estimating runout path and distance. This approach optimizes the random-walk and Perla et al.'s (PCM) two-parameter friction model components of the open-source Gravitational Process Path (GPP) modelling framework. To validate model performance, we assess the spatial transferability of the optimized runout model using spatial crossvalidation, including exploring the model's sensitivity to sample size. We also present diagnostic tools for visualizing uncertainties in parameter selection and model performance. Although there was considerable variation in optimal parameters for individual events, we found our runout modelling approach performed well at regional prediction of potential runout areas. We also found that although a relatively small sample size was sufficient to achieve generally good runout modelling performance, larger samples sizes (i.e. >= 80) had higher model performance and lower uncertainties for estimating runout distances at unknown locations. We anticipate that this automated approach using the open-source R software and the System for Automated Geoscientific Analyses geographic information system (SAGA-GIS) will make process-based debris-flow models more readily accessible and thus enable researchers and spatial planners to improve regional-scale hazard assessments.
Y1  - 2021
U6  - https://doi.org/10.5194/nhess-21-2543-2021
SN  - 1561-8633
SN  - 1684-9981
VL  - 21
IS  - 8
SP  - 2543
EP  - 2562
PB  - European Geophysical Society
CY  - Katlenburg-Lindau
ER  - 
TY  - JOUR
A1  - Krummenauer, Linda
A1  - Costa, Luís Fílípe Carvalho da
A1  - Prahl, Boris F.
A1  - Kropp, Jürgen
T1  - Future heat adaptation and exposure among urban populations and why a prospering economy alone won’t save us
JF  - Scientific reports
N2  - When inferring on the magnitude of future heat-related mortality due to climate change, human adaptation to heat should be accounted for. We model long-term changes in minimum mortality temperatures (MMT), a well-established metric denoting the lowest risk of heat-related mortality, as a function of climate change and socio-economic progress across 3820 cities. Depending on the combination of climate trajectories and socio-economic pathways evaluated, by 2100 the risk to human health is expected to decline in 60% to 80% of the cities against contemporary conditions. This is caused by an average global increase in MMTs driven by long-term human acclimatisation to future climatic conditions and economic development of countries. While our adaptation model suggests that negative effects on health from global warming can broadly be kept in check, the trade-offs are highly contingent to the scenario path and location-specific. For high-forcing climate scenarios (e.g. RCP8.5) the maintenance of uninterrupted high economic growth by 2100 is a hard requirement to increase MMTs and level-off the negative health effects from additional scenario-driven heat exposure. Choosing a 2 degrees C-compatible climate trajectory alleviates the dependence on fast growth, leaving room for a sustainable economy, and leads to higher reductions of mortality risk.
Y1  - 2021
U6  - https://doi.org/10.1038/s41598-021-99757-0
SN  - 2045-2322
VL  - 11
IS  - 1
PB  - Macmillan Publishers Limited, part of Springer Nature
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Schneidemesser, Erika von
A1  - Sibiya, Bheki
A1  - Caseiro, Alexandre
A1  - Butler, Tim
A1  - Lawrence, Mark
A1  - Leitao, Joana
A1  - Lupaşcu, Aura
A1  - Salvador, Pedro
T1  - Learning from the COVID-19 lockdown in Berlin
BT  - Observations and modelling to support understanding policies to reduce NO2
JF  - Atmospheric environment: X
N2  - Urban air pollution is a substantial threat to human health. Traffic emissions remain a large contributor to air pollution in urban areas. The mobility restrictions put in place in response to the COVID-19 pandemic provided a large-scale real-world experiment that allows for the evaluation of changes in traffic emissions and the corresponding changes in air quality. Here we use observational data, as well as modelling, to analyse changes in nitrogen dioxide, ozone, and particulate matter resulting from the COVID-19 restrictions at the height of the lockdown period in Spring of 2020. Accounting for the influence of meteorology on air quality, we found that reduction of ca. 30-50 % in traffic counts, dominated by changes in passenger cars, corresponded to reductions in median observed nitrogen dioxide concentrations of ca. 40 % (traffic and urban background locations) and a ca. 22 % increase in ozone (urban background locations) during weekdays. Lesser reductions in nitrogen dioxide concentrations were observed at urban background stations at weekends, and no change in ozone was observed. The modelled reductions in median nitrogen dioxide at urban background locations were smaller than the observed reductions and the change was not significant. The model results showed no significant change in ozone on weekdays or weekends. The lack of a simulated weekday/weekend effect is consistent with previous work suggesting that NOx emissions from traffic could be significantly underestimated in European cities by models. These results indicate the potential for improvements in air quality due to policies for reducing traffic, along with the scale of reductions that would be needed to result in meaningful changes in air quality if a transition to sustainable mobility is to be seriously considered. They also confirm once more the highly relevant role of traffic for air quality in urban areas.
KW  - Urban areas
KW  - Air pollution
KW  - Emissions
KW  - COVID-19
KW  - Nitrogen dioxide
KW  - Ozone
KW  - Europe
Y1  - 2021
U6  - https://doi.org/10.1016/j.aeaoa.2021.100122
SN  - 2590-1621
VL  - 12
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Schaller, Jörg
A1  - Puppe, Daniel
A1  - Kaczorek, Danuta
A1  - Ellerbrock, Ruth
A1  - Sommer, Michael
T1  - Silicon cycling in soils revisited
JF  - Plants : open access journal
N2  - Silicon (Si) speciation and availability in soils is highly important for ecosystem functioning, because Si is a beneficial element for plant growth. Si chemistry is highly complex compared to other elements in soils, because Si reaction rates are relatively slow and dependent on Si species. Consequently, we review the occurrence of different Si species in soil solution and their changes by polymerization, depolymerization, and condensation in relation to important soil processes. We show that an argumentation based on thermodynamic endmembers of Si dependent processes, as currently done, is often difficult, because some reactions such as mineral crystallization require months to years (sometimes even centuries or millennia). Furthermore, we give an overview of Si reactions in soil solution and the predominance of certain solid compounds, which is a neglected but important parameter controlling the availability, reactivity, and function of Si in soils. We further discuss the drivers of soil Si cycling and how humans interfere with these processes. The soil Si cycle is of major importance for ecosystem functioning; therefore, a deeper understanding of drivers of Si cycling (e.g., predominant speciation), human disturbances and the implication for important soil properties (water storage, nutrient availability, and micro aggregate stability) is of fundamental relevance.
KW  - andosols
KW  - clay neoformation
KW  - crop yield
KW  - land use change
KW  - micro
KW  - aggregate stability
KW  - phytoliths
KW  - sediments
KW  - silicon cycling
KW  - silicon
KW  - extraction methods
KW  - silicon pore water speciation
Y1  - 2021
U6  - https://doi.org/10.3390/plants10020295
SN  - 2223-7747
VL  - 10
IS  - 2
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Devitt, Laura
A1  - Neal, Jeffrey
A1  - Wagener, Thorsten
A1  - Coxon, Gemma
T1  - Uncertainty in the extreme flood magnitude estimates of large-scale flood hazard models
JF  - Environmental research letters : ERL / Institute of Physics
N2  - The growing worldwide impact of flood events has motivated the development and application of global flood hazard models (GFHMs). These models have become useful tools for flood risk assessment and management, especially in regions where little local hazard information is available. One of the key uncertainties associated with GFHMs is the estimation of extreme flood magnitudes to generate flood hazard maps. In this study, the 1-in-100 year flood (Q100) magnitude was estimated using flow outputs from four global hydrological models (GHMs) and two global flood frequency analysis datasets for 1350 gauges across the conterminous US. The annual maximum flows of the observed and modelled timeseries of streamflow were bootstrapped to evaluate the sensitivity of the underlying data to extrapolation. Results show that there are clear spatial patterns of bias associated with each method. GHMs show a general tendency to overpredict Western US gauges and underpredict Eastern US gauges. The GloFAS and HYPE models underpredict Q100 by more than 25% in 68% and 52% of gauges, respectively. The PCR-GLOBWB and CaMa-Flood models overestimate Q100 by more than 25% at 60% and 65% of gauges in West and Central US, respectively. The global frequency analysis datasets have spatial variabilities that differ from the GHMs. We found that river basin area and topographic elevation explain some of the spatial variability in predictive performance found in this study. However, there is no single model or method that performs best everywhere, and therefore we recommend a weighted ensemble of predictions of extreme flood magnitudes should be used for large-scale flood hazard assessment.
KW  - large-scale flood hazard models
KW  - global hydrological model
KW  - flood risk
Y1  - 2021
U6  - https://doi.org/10.1088/1748-9326/abfac4
SN  - 1748-9326
VL  - 16
IS  - 6
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Rottler, Erwin
A1  - Vormoor, Klaus Josef
A1  - Francke, Till
A1  - Warscher, Michael
A1  - Strasser, Ulrich
A1  - Bronstert, Axel
T1  - Elevation-dependent compensation effects in snowmelt in the Rhine River Basin upstream gauge Basel
JF  - Hydrology research : an international journal / Nordic Association of Hydrology ; British Hydrological Society
N2  - In snow-dominated river basins, floods often occur during early summer, when snowmelt-induced runoff superimposes with rainfall-induced runoff. An earlier onset of seasonal snowmelt as a consequence of a warming climate is often expected to shift snowmelt contribution to river runoff and potential flooding to an earlier date. Against this background, we assess the impact of rising temperatures on seasonal snowpacks and quantify changes in timing, magnitude and elevation of snowmelt. We analyse in situ snow measurements, conduct snow simulations and examine changes in river runoff at key gauging stations. With regard to snowmelt, we detect a threefold effect of rising temperatures: snowmelt becomes weaker, occurs earlier and forms at higher elevations. Due to the wide range of elevations in the catchment, snowmelt does not occur simultaneously at all elevations. Results indicate that elevation bands melt together in blocks. We hypothesise that in a warmer world with similar sequences of weather conditions, snowmelt is moved upward to higher elevation. The movement upward the elevation range makes snowmelt in individual elevation bands occur earlier, although the timing of the snowmelt-induced runoff stays the same. Meltwater from higher elevations, at least partly, replaces meltwater from elevations below.
KW  - compensation effects
KW  - elevation-dependency
KW  - Rhine River
KW  - snowmelt
KW  - timing
Y1  - 2021
U6  - https://doi.org/10.2166/nh.2021.092
SN  - 2224-7955
VL  - 52
IS  - 2
SP  - 536
EP  - 557
PB  - IWA Publ.
CY  - London
ER  - 
TY  - JOUR
A1  - Seleem, Omar
A1  - Heistermann, Maik
A1  - Bronstert, Axel
T1  - Efficient Hazard Assessment For Pluvial Floods In Urban Environments
BT  - A Benchmarking Case Study For The City Of Berlin, Germany
JF  - Water
N2  - The presence of impermeable surfaces in urban areas hinders natural drainage and directs the surface runoff to storm drainage systems with finite capacity, which makes these areas prone to pluvial flooding. The occurrence of pluvial flooding depends on the existence of minimal areas for surface runoff generation and concentration. Detailed hydrologic and hydrodynamic simulations are computationally expensive and require intensive resources. This study compared and evaluated the performance of two simplified methods to identify urban pluvial flood-prone areas, namely the fill–spill–merge (FSM) method and the topographic wetness index (TWI) method and used the TELEMAC-2D hydrodynamic numerical model for benchmarking and validation. The FSM method uses common GIS operations to identify flood-prone depressions from a high-resolution digital elevation model (DEM). The TWI method employs the maximum likelihood method (MLE) to probabilistically calibrate a TWI threshold (τ) based on the inundation maps from a 2D hydrodynamic model for a given spatial window (W) within the urban area. We found that the FSM method clearly outperforms the TWI method both conceptually and effectively in terms of model performance.
KW  - urban pluvial flooding
KW  - digital elevation model (DEM)
KW  - fill–spill–merge method
KW  - topographic wetness index (TWI)
KW  - TELEMAC-2D model
KW  - flood-prone area
Y1  - 2021
U6  - https://doi.org/10.3390/w13182476
SN  - 2073-4441
VL  - 13
IS  - 18
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Vogel, Johannes
A1  - Paton, Eva
A1  - Aich, Valentin
A1  - Bronstert, Axel
T1  - Increasing compound warm spells and droughts in the Mediterranean Basin
JF  - Weather and climate extremes
N2  - The co-occurrence of warm spells and droughts can lead to detrimental socio-economic and ecological impacts, largely surpassing the impacts of either warm spells or droughts alone. We quantify changes in the number of compound warm spells and droughts from 1979 to 2018 in the Mediterranean Basin using the ERA5 data set. We analyse two types of compound events: 1) warm season compound events, which are extreme in absolute terms in the warm season from May to October and 2) year-round deseasonalised compound events, which are extreme in relative terms respective to the time of the year. The number of compound events increases significantly and especially warm spells are increasing strongly – with an annual growth rates of 3.9 (3.5) % for warm season (deseasonalised) compound events and 4.6 (4.4) % for warm spells –, whereas for droughts the change is more ambiguous depending on the applied definition. Therefore, the rise in the number of compound events is primarily driven by temperature changes and not the lack of precipitation. The months July and August show the highest increases in warm season compound events, whereas the highest increases of deseasonalised compound events occur in spring and early summer. This increase in deseasonalised compound events can potentially have a significant impact on the functioning of Mediterranean ecosystems as this is the peak phase of ecosystem productivity and a vital phenophase.
KW  - Compound events
KW  - Warm spells
KW  - Droughts
KW  - Mediterranean basin
KW  - Extreme events
KW  - Climate change
Y1  - 2021
U6  - https://doi.org/10.1016/j.wace.2021.100312
SN  - 2212-0947
VL  - 32
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bürger, Gerd
A1  - Pfister, Angela
A1  - Bronstert, Axel
T1  - Zunehmende Starkregenintensitäten als Folge der Klimaerwärmung
T1  - Increasing intensity of heavy rainfall caused by global warming
BT  - Datenanalyse und Zukunftsprojektion
BT  - data analysis and future projections
JF  - Hydrologie und Wasserbewirtschaftung : HyWa = Hydrology and water resources management, Germany / Hrsg.: Fachverwaltungen des Bundes und der Länder
N2  - Extreme rainfall events of short duration in the range of hours and below are increasingly coming into focus due to the resulting damage from flash floods and also due to their possible intensification by anthropogenic climate change. The current study investigates possible trends in heavy rainfall intensities for stations from Swiss and Austrian alpine regions as well as for the Emscher-Lippe area in North Rhine-Westphalia on the basis of partly very long (> 50 years) and temporally highly resolved time series (<= 15 minutes). It becomes clear that there is an increase in extreme rainfall intensities, which can be well explained by the warming of the regional climate: the analyses of long-term trends in exceedance counts and return levels show considerable uncertainties, but are in the order of 30 % increase per century. In addition, based on an "average" climate simulation for the 21st century, this paper describes a projection for extreme precipitation intensities at very high temporal resolution for a number of stations in the Emscher-Lippe region. A coupled spatial and temporal "downscaling" is applied, the key innovation of which is the consideration of the dependence of local rainfall intensity on air temperature. This procedure involves two steps: First, large-scale climate fields at daily resolution are statistically linked by regression to station temperature and precipitation values (spatial downscaling). In the second step, these station values are disaggregated to a temporal resolution of 10 minutes using a so-called multiplicative stochastic cascade model (MC) (temporal downscaling). The novel, temperature-sensitive variant additionally considers air temperature as an explanatory variable for precipitation intensities. Thus, the higher atmospheric moisture content expected with warming, which results from the Clausius-Clapeyron (CC) relationship, is included in the temporal downscaling. <br /> For the statistical evaluation of the extreme short-term precipitation, the upper quantiles (99.9 %), exceedance counts (P > 5mm), and 3-yr return levels of the <= 15-min duration step has been used. Only by adding temperature is the observed temperature observed of the extreme quantiles ("CC scaling") well reproduced. When comparing observed data and present-day simulations of the model cascade, the temperature-sensitive procedure shows consistent results. Compared to trends in recent decades, similar or even larger increases in extreme intensities are projected for the future. This is remarkable in that these appear to be driven primarily by local temperature, as the projected trends in daily precipitation values are negligible for this region.
N2  - Extreme Regenereignisse von kurzer Dauer im Bereich von Stunden und darunter rücken aufgrund der dadurch bedingten Schäden durch Sturzfluten und auch wegen ihrer möglichen Intensivierungen durch den anthropogenen Klimawandel immer stärker in den Fokus. Die vorliegende Studie untersucht auf Basis von teilweise sehr langen (> 50 Jahre) und zeitlich hochaufgelösten Zeitreihen (≤ 15 Minuten) mögliche Trends in Starkregenintensitäten für Stationen aus schweizerischen und österreichischen Alpenregionen sowie für das Emscher-Lippe-Gebiet in Nordrhein-Westfalen. Es wird deutlich, dass es eine Zunahme der extremen Niederschlagsintensitäten gibt, welche gut durch die Erwärmung des regionalen Klimas erklärt werden kann: Die Analysen langfristiger Trends der Überschreitungssummen und Wiederkehrniveaus zeigen zwar erhebliche Unsicherheiten, lassen jedoch eine Zunahme in einer Größenordnung von 30 % pro Jahrhundert erkennen. Zudem wird in diesem Beitrag, basierend auf einer "mittleren" Klimasimulation für das 21. Jahrhundert, für ausgewählte Stationen der Emscher-Lippe-Region eine Projektion für extreme Niederschlagsintensitäten in sehr hoher zeitlicher Auflösung beschrieben. Dabei wird ein gekoppeltes räumliches und zeitliches "Downscaling" angewendet, dessen entscheidende Neuerung die Berücksichtigung der Abhängigkeit der lokalen Regenintensität von der Lufttemperatur ist. Dieses Verfahren beinhaltet zwei Schritte: Zuerst werden großräumige Klimafelder in täglicher Auflösung durch Regression mit den Temperatur- und Niederschlagswerten der Stationen statistisch verbunden (räumliches Downscaling). Im zweiten Schritt werden dann diese Stationswerte mithilfe eines sogenannten multiplikativen stochastischen Kaskadenmodells (MC) auf eine zeitliche Auflösung von 10 Minuten disaggregiert (zeitliches Downscaling). Die neuartige, temperatursensitive Variante berücksichtigt zusätzlich die Lufttemperatur als erklärende Variable für die Niederschlagsintensitäten. Dadurch wird der mit einer Erwärmung zu erwartende höhere atmosphärische Feuchtegehalt, welcher sich aus der Clausius-Clapeyron-Beziehung (CC) ergibt, mit in das zeitliche Downscaling einbezogen.
Für die statistische Auswertung der extremen kurzfristigen Niederschläge wurden die oberen Quantile (99,9 %), Überschreitungssummen (ÜS, P > 5 mm) und 3-jährliche Wiederkehrniveaus (WN) einer Dauerstufe von ≤ 15-Minuten betrachtet. Diese Auswahl erlaubt die gleichzeitige Analyse sowohl von Extremwertstatistiken als auch von deren langfristigen Trends; leichte Abweichungen von dieser Wahl beeinflussen die Hauptergebnisse nur unwesentlich. Nur durch die Hinzunahme der Temperatur wird die beobachtete Temperaturabhängigkeit der extremen Quantile (CC-Scaling) gut wiedergegeben. Bei Vergleich von Beobachtungsdaten und Gegenwartssimulationen der Modellkaskade zeigt das temperatursensitive Verfahren konsistente Ergebnisse. Im Vergleich zu den Entwicklungen der letzten Jahrzehnte werden für die Zukunft ähnliche oder sogar noch stärkere Anstiege der extremen Niederschlagsintensitäten projiziert. Dies ist insofern bemerkenswert, als diese anscheinend hauptsächlich durch die örtliche Temperatur bestimmt werden, denn die projizierten Trends der Niederschlags-Tageswerte sind für diese Region vernachlässigbar.
KW  - heavy rainfall
KW  - short duration
KW  - global warming
KW  - Clausius-Clapeyron
KW  - equation
KW  - precipitation intensity
KW  - multiplicative cascade model
KW  - Strakregen
KW  - kurzfristige Dauerstufe
KW  - Klimawandel
KW  - Clausius-Clapeyron-Gleichung
KW  - Niederschlagsintensitäten
KW  - Multiplikatives Kaskadenmodel
Y1  - 2021
U6  - https://doi.org/10.5675/HyWa_2021.6_1
SN  - 1439-1783
SN  - 2749-859X
VL  - 65
IS  - 6
SP  - 262
EP  - 271
PB  - Bundesanst. für Gewässerkunde
CY  - Koblenz
ER  - 
TY  - JOUR
A1  - Tötzke, Christian
A1  - Kardjilov, Nikolay
A1  - Hilger, André
A1  - Rudolph-Mohr, Nicole
A1  - Manke, Ingo
A1  - Oswald, Sascha
T1  - Three-dimensional in vivo analysis of water uptake and translocation in maize roots by fast neutron tomography
JF  - Scientific Reports
N2  - Root water uptake is an essential process for terrestrial plants that strongly affects the spatiotemporal distribution of water in vegetated soil. Fast neutron tomography is a recently established non-invasive imaging technique capable to capture the 3D architecture of root systems in situ and even allows for tracking of three-dimensional water flow in soil and roots. We present an in vivo analysis of local water uptake and transport by roots of soil-grown maize plants—for the first time measured in a three-dimensional time-resolved manner. Using deuterated water as tracer in infiltration experiments, we visualized soil imbibition, local root uptake, and tracked the transport of deuterated water throughout the fibrous root system for a day and night situation. This revealed significant differences in water transport between different root types. The primary root was the preferred water transport path in the 13-days-old plants while seminal roots of comparable size and length contributed little to plant water supply. The results underline the unique potential of fast neutron tomography to provide time-resolved 3D in vivo information on the water uptake and transport dynamics of plant root systems, thus contributing to a better understanding of the complex interactions of plant, soil and water.
KW  - Environmental sciences
KW  - Optics and photonics
KW  - Plant sciences
Y1  - 2021
U6  - https://doi.org/10.1038/s41598-021-90062-4
SN  - 2045-2322
VL  - 11
PB  - Macmillan Publishers Limited
CY  - London
ER  - 
TY  - JOUR
A1  - Heistermann, Maik
A1  - Francke, Till
A1  - Schrön, Martin
A1  - Oswald, Sascha
T1  - Spatio-temporal soil moisture retrieval at the catchment scale using a dense network of cosmic-ray neutron sensors
JF  - Hydrology and Earth System Sciences (HESS)
N2  - Cosmic-ray neutron sensing (CRNS) is a powerful technique for retrieving representative estimates of soil water content at a horizontal scale of hectometres (the “field scale”) and depths of tens of centimetres (“the root zone”). This study demonstrates the potential of the CRNS technique to obtain spatio-temporal patterns of soil moisture beyond the integrated volume from isolated CRNS footprints. We use data from an observational campaign carried out between May and July 2019 that featured a dense network of more than 20 neutron detectors with partly overlapping footprints in an area that exhibits pronounced soil moisture gradients within one square kilometre. The present study is the first to combine these observations in order to represent the heterogeneity of soil water content at the sub-footprint scale as well as between the CRNS stations. First, we apply a state-of-the-art procedure to correct the observed neutron count rates for static effects (heterogeneity in space, e.g. soil organic matter) and dynamic effects (heterogeneity in time, e.g. barometric pressure). Based on the homogenized neutron data, we investigate the robustness of a calibration approach that uses a single calibration parameter across all CRNS stations. Finally, we benchmark two different interpolation techniques for obtaining spatio-temporal representations of soil moisture: first, ordinary Kriging with a fixed range; second, spatial interpolation complemented by geophysical inversion (“constrained interpolation”). To that end, we optimize the parameters of a geostatistical interpolation model so that the error in the forward-simulated neutron count rates is minimized, and suggest a heuristic forward operator to make the optimization problem computationally feasible. Comparison with independent measurements from a cluster of soil moisture sensors (SoilNet) shows that the constrained interpolation approach is superior for representing horizontal soil moisture gradients at the hectometre scale. The study demonstrates how a CRNS network can be used to generate coherent, consistent, and continuous soil moisture patterns that could be used to validate hydrological models or remote sensing products.
Y1  - 2021
U6  - https://doi.org/10.5194/hess-25-4807-2021
SN  - 1607-7938
VL  - 25
PB  - Copernicus Publications
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Speckhann, Gustavo Andrei
A1  - Kreibich, Heidi
A1  - Merz, Bruno
T1  - Inventory of dams in Germany
JF  - Earth system science data : the data publishing journal
N2  - Dams are an important element of water resources management. Data about dams are crucial for practitioners, scientists, and policymakers for various purposes, such as seasonal forecasting of water availability or flood mitigation. However, detailed information on dams on the national level for Germany is so far not freely available. We present the most comprehensive open-access dam inventory for Germany (DIG) to date. We have collected and combined information on dams using books, state agency reports, engineering reports, and internet pages. We have applied a priority rule that ensures the highest level of reliability for the dam information. Our dam inventory comprises 530 dams in Germany with information on name, location, river, start year of construction and operation, crest length, dam height, lake area, lake volume, purpose, dam structure, and building characteristics. We have used a global, satellite-based water surface raster to evaluate the location of the dams. A significant proportion (63 %) of dams were built between 1950-2013. Our inventory shows that dams in Germany are mostly single-purpose (52 %), 53% can be used for flood control, and 25% are involved in energy production. The inventory is freely available through GFZ (GeoForschungsZentrum) Data Services (https://doi.org/10.5880/GFZ.4.4.2020.005)
Y1  - 2021
U6  - https://doi.org/10.5194/essd-13-731-2021
SN  - 1866-3508
SN  - 1866-3516
VL  - 13
IS  - 2
SP  - 731
EP  - 740
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Rottler, Erwin
A1  - Bronstert, Axel
A1  - Bürger, Gerd
A1  - Rakovec, Oldrich
T1  - Projected changes in Rhine River flood seasonality under global warming
JF  - Hydrology and earth system sciences : HESS / European Geosciences Union
N2  - Climatic change alters the frequency and intensity of natural hazards. In order to assess potential future changes in flood seasonality in the Rhine River Basin, we analyse changes in streamflow, snowmelt, precipitation, and evapotranspiration at 1.5, 2.0 and 3.0 ◦C global warming levels. The mesoscale Hydrological Model (mHM) forced with an ensemble of climate projection scenarios (five general circulation models under three representative concentration pathways) is used to simulate the present and future climate conditions of both, pluvial and nival hydrological regimes. Our results indicate that the interplay between changes in snowmelt- and rainfall-driven runoff is crucial to understand changes in streamflow maxima in the Rhine River. Climate projections suggest that future changes in flood characteristics in the entire Rhine River are controlled by both, more intense precipitation events and diminishing snow packs. The nature of this interplay defines the type of change in runoff peaks. On the sub-basin level (the Moselle River), more intense rainfall during winter is mostly counterbalanced by reduced snowmelt contribution to the streamflow. In the High Rhine (gauge at Basel), the strongest increases in streamflow maxima show up during winter, when strong increases in liquid precipitation intensity encounter almost unchanged snowmelt-driven runoff. The analysis of snowmelt events suggests that at no point in time during the snowmelt season, a warming climate results in an increase in the risk of snowmelt-driven flooding. We do not find indications of a transient merging of pluvial and nival floods due to climate warming.
Y1  - 2020
U6  - https://doi.org/10.5194/hess-25-2353-2021
SN  - 1607-7938
SN  - 1027-5606
VL  - 25
IS  - 5
SP  - 2353
EP  - 2371
PB  - Copernicus Publications
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Courtin, Jérémy
A1  - Andreev, Andrei
A1  - Raschke, Elena
A1  - Bala, Sarah
A1  - Biskaborn, Boris
A1  - Liu, Sisi
A1  - Zimmermann, Heike
A1  - Diekmann, Bernhard
A1  - Stoof-Leichsenring, Kathleen R.
A1  - Pestryakova, Luidmila Agafyevna
A1  - Herzschuh, Ulrike
T1  - Vegetation changes in Southeastern Siberia during the late pleistocene and the holocene
JF  - Frontiers in Ecology and Evolution
N2  - Relationships between climate, species composition, and species richness are of particular importance for understanding how boreal ecosystems will respond to ongoing climate change. This study aims to reconstruct changes in terrestrial vegetation composition and taxa richness during the glacial Late Pleistocene and the interglacial Holocene in the sparsely studied southeastern Yakutia (Siberia) by using pollen and sedimentary ancient DNA (sedaDNA) records. Pollen and sedaDNA metabarcoding data using the trnL g and h markers were obtained from a sediment core from Lake Bolshoe Toko. Both proxies were used to reconstruct the vegetation composition, while metabarcoding data were also used to investigate changes in plant taxa richness. The combination of pollen and sedaDNA approaches allows a robust estimation of regional and local past terrestrial vegetation composition around Bolshoe Toko during the last similar to 35,000 years. Both proxies suggest that during the Late Pleistocene, southeastern Siberia was covered by open steppe-tundra dominated by graminoids and forbs with patches of shrubs, confirming that steppe-tundra extended far south in Siberia. Both proxies show disturbance at the transition between the Late Pleistocene and the Holocene suggesting a period with scarce vegetation, changes in the hydrochemical conditions in the lake, and in sedimentation rates. Both proxies document drastic changes in vegetation composition in the early Holocene with an increased number of trees and shrubs and the appearance of new tree taxa in the lake's vicinity. The sedaDNA method suggests that the Late Pleistocene steppe-tundra vegetation supported a higher number of terrestrial plant taxa than the forested Holocene. This could be explained, for example, by the "keystone herbivore" hypothesis, which suggests that Late Pleistocene megaherbivores were able to maintain a high plant diversity. This is discussed in the light of the data with the broadly accepted species-area hypothesis as steppe-tundra covered such an extensive area during the Late Pleistocene.
KW  - last glacial
KW  - Holocene
KW  - Lake Bolshoe Toko
KW  - paleoenvironments
KW  - sedimentary ancient DNA
KW  - metabarcoding
KW  - trnL
KW  - pollen
Y1  - 2021
U6  - https://doi.org/10.3389/fevo.2021.625096
SN  - 2296-701X
VL  - 9
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Glückler, Ramesh
A1  - Herzschuh, Ulrike
A1  - Kruse, Stefan
A1  - Andreev, Andrei
A1  - Vyse, Stuart Andrew
A1  - Winkler, Bettina
A1  - Biskaborn, Boris
A1  - Pestryakova, Luidmila Agafyevna
A1  - Dietze, Elisabeth
T1  - Wildfire history of the boreal forest of south-western Yakutia (Siberia) over the last two millennia documented by a lake-sediment charcoal record
JF  - Biogeosciences : BG / European Geosciences Union
N2  - Wildfires, as a key disturbance in forest ecosystems, are shaping the world's boreal landscapes. Changes in fire regimes are closely linked to a wide array of environmental factors, such as vegetation composition, climate change, and human activity. Arctic and boreal regions and, in particular, Siberian boreal forests are experiencing rising air and ground temperatures with the subsequent degradation of permafrost soils leading to shifts in tree cover and species composition. Compared to the boreal zones of North America or Europe, little is known about how such environmental changes might influence long-term fire regimes in Russia. The larch-dominated eastern Siberian deciduous boreal forests differ markedly from the composition of other boreal forests, yet data about past fire regimes remain sparse. Here, we present a high-resolution macroscopic charcoal record from lacustrine sediments of Lake Khamra (southwest Yakutia, Siberia) spanning the last ca. 2200 years, including information about charcoal particle sizes and morphotypes. Our results reveal a phase of increased charcoal accumulation between 600 and 900 CE, indicative of relatively high amounts of burnt biomass and high fire frequencies. This is followed by an almost 900-year-long period of low charcoal accumulation without significant peaks likely corresponding to cooler climate conditions. After 1750 CE fire frequencies and the relative amount of biomass burnt start to increase again, coinciding with a warming climate and increased anthropogenic land development after Russian colonization. In the 20th century, total charcoal accumulation decreases again to very low levels despite higher fire frequency, potentially reflecting a change in fire management strategies and/or a shift of the fire regime towards more frequent but smaller fires. A similar pattern for different charcoal morphotypes and comparison to a pollen and non-pollen palynomorph (NPP) record from the same sediment core indicate that broad-scale changes in vegetation composition were probably not a major driver of recorded fire regime changes. Instead, the fire regime of the last two millennia at Lake Khamra seems to be controlled mainly by a combination of short-term climate variability and anthropogenic fire ignition and suppression.
Y1  - 2021
U6  - https://doi.org/10.5194/bg-18-4185-2021
SN  - 1726-4170
SN  - 1726-4189
VL  - 18
IS  - 13
SP  - 4185
EP  - 4209
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Romero Barbosa, Luís
A1  - Coelho, Victor Hugo R.
A1  - Scheiffele, Lena
A1  - Baroni, Gabriele
A1  - Ramos Filho, Geraldo M.
A1  - Montenegro, Suzana M. G. L.
A1  - Das Neves Almeida, Cristiano
A1  - Oswald, Sascha
T1  - Dynamic groundwater recharge simulations based on cosmic-ray neutron sensing in a tropical wet experimental basin
JF  - Vadose zone journal : VZJ : advancing critical zone science
N2  - Although cosmic-ray neutron sensing (CRNS) is probably the most promising noninvasive proximal soil moisture measurement technique at the field scale, its application for hydrological simulations remains underexplored in the literature so far. This study assessed the use of CRNS to inversely calibrate soil hydraulic parameters at the intermediate field scale to simulate the groundwater recharge rates at a daily timescale. The study was conducted for two contrasting hydrological years at the Guaraira experimental basin, Brazil, a 5.84-km(2), a tropical wet and rather flat landscape covered by secondary Atlantic forest. As a consequence of the low altitude and proximity to the equator low neutron count rates could be expected, reducing the precision of CRNS while constituting unexplored and challenging conditions for CRNS applications. Inverse calibration for groundwater recharge rates was used based on CRNS or point-scale soil moisture data. The CRNS-derived retention curve and saturated hydraulic conductivity were consistent with the literature and locally performed slug tests. Simulated groundwater recharge rates ranged from 60 to 470 mm yr(-1), corresponding to 5 and 29% of rainfall, and correlated well with estimates based on water table fluctuations. In contrast, the estimated results based on inversive point-scale datasets were not in alignment with measured water table fluctuations. The better performance of CRNS-based estimations of field-scale hydrological variables, especially groundwater recharge, demonstrated its clear advantages over traditional invasive point-scale techniques. Finally, the study proved the ability of CRNS as practicable in low altitude, tropical wet areas, thus encouraging its adoption for water resources monitoring and management.
Y1  - 2021
U6  - https://doi.org/10.1002/vzj2.20145
SN  - 1539-1663
VL  - 20
IS  - 4
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Voit, Paul
A1  - Heistermann, Maik
T1  - A new index to quantify the extremeness of precipitation across scales
JF  - NHESS - Natural Hazards and Earth System Sciences
N2  - Quantifying the extremeness of heavy precipitation allows for the comparison of events. Conventional quantitative indices, however, typically neglect the spatial extent or the duration, while both are important to understand potential impacts. In 2014, the weather extremity index (WEI) was suggested to quantify the extremeness of an event and to identify the spatial and temporal scale at which the event was most extreme. However, the WEI does not account for the fact that one event can be extreme at various spatial and temporal scales. To better understand and detect the compound nature of precipitation events, we suggest complementing the original WEI with a “cross-scale weather extremity index” (xWEI), which integrates extremeness over relevant scales instead of determining its maximum.

Based on a set of 101 extreme precipitation events in Germany, we outline and demonstrate the computation of both WEI and xWEI. We find that the choice of the index can lead to considerable differences in the assessment of past events but that the most extreme events are ranked consistently, independently of the index. Even then, the xWEI can reveal cross-scale properties which would otherwise remain hidden. This also applies to the disastrous event from July 2021, which clearly outranks all other analyzed events with regard to both WEI and xWEI.

While demonstrating the added value of xWEI, we also identify various methodological challenges along the required computational workflow: these include the parameter estimation for the extreme value distributions, the definition of maximum spatial extent and temporal duration, and the weighting of extremeness at different scales. These challenges, however, also represent opportunities to adjust the retrieval of WEI and xWEI to specific user requirements and application scenarios.
Y1  - 2022
U6  - https://doi.org/10.5194/nhess-22-2791-2022
SN  - 1684-9981
VL  - 22
SP  - 2791
EP  - 2805
PB  - Copernicus
CY  - Katlenburg-Lindau
ET  - 8
ER  - 
TY  - JOUR
A1  - Fischer, Melanie
A1  - Brettin, Jana
A1  - Roessner, Sigrid
A1  - Walz, Ariane
A1  - Fort, Monique
A1  - Korup, Oliver
T1  - Rare flood scenarios for a rapidly growing high-mountain city: Pokhara, Nepal
JF  - Natural Hazards and Earth System Sciences
N2  - Pokhara (ca. 850 m a.s.l.), Nepal's second-largest city, lies at the foot of the Higher Himalayas and has more than tripled its population in the past 3 decades. Construction materials are in high demand in rapidly expanding built-up areas, and several informal settlements cater to unregulated sand and gravel mining in the Pokhara Valley's main river, the Seti Khola. This river is fed by the Sabche glacier below Annapurna III (7555 m a.s.l.), some 35 km upstream of the city, and traverses one of the steepest topographic gradients in the Himalayas. In May 2012 a sudden flood caused >70 fatalities and intense damage along this river and rekindled concerns about flood risk management. We estimate the flow dynamics and inundation depths of flood scenarios using the hydrodynamic model HEC-RAS (Hydrologic Engineering Center’s River Analysis System). We simulate the potential impacts of peak discharges from 1000 to 10 000 m3 s−1 on land cover based on high-resolution Maxar satellite imagery and OpenStreetMap data (buildings and road network). We also trace the dynamics of two informal settlements near Kaseri and Yamdi with high potential flood impact from RapidEye, PlanetScope, and Google Earth imagery of the past 2 decades. Our hydrodynamic simulations highlight several sites of potential hydraulic ponding that would largely affect these informal settlements and sites of sand and gravel mining. These built-up areas grew between 3- and 20-fold, thus likely raising local flood exposure well beyond changes in flood hazard. Besides these drastic local changes, about 1 % of Pokhara's built-up urban area and essential rural road network is in the highest-hazard zones highlighted by our flood simulations. Our results stress the need to adapt early-warning strategies for locally differing hydrological and geomorphic conditions in this rapidly growing urban watershed.
Y1  - 2022
U6  - https://doi.org/10.5194/nhess-22-3105-2022
SN  - 1684-9981
VL  - 22
SP  - 3105
EP  - 3123
PB  - Copernicus Publications
CY  - Katlenburg-Lindau
ET  - 9
ER  - 
TY  - JOUR
A1  - Sieg, Tobias
A1  - Thieken, Annegret
T1  - Improving flood impact estimations
JF  - Environmental research letters
N2  - A reliable estimation of flood impacts enables meaningful flood risk management and rapid assessments of flood impacts shortly after a flood. The flood in 2021 in Central Europe and the analysis of its impacts revealed that these estimations are still inadequate. Therefore, we investigate the influence of different data sets and methods aiming to improve flood impact estimates. We estimated economic flood impacts to private households and companies for a flood event in 2013 in Germany using (a) two different flood maps, (b) two approaches to map exposed objects based on OpenStreetMap and the Basic European Asset Map, (c) two different approaches to estimate asset values, and (d) tree-based models and Stage-Damage-Functions to describe the vulnerability. At the macro scale, water masks lead to reasonable impact estimations. At the micro and meso-scale, the identification of affected objects by means of water masks is insufficient leading to unreliable estimations. The choice of exposure data sets is most influential on the estimations. We find that reliable impact estimations are feasible with reported numbers of flood-affected objects from the municipalities. We conclude that more effort should be put in the investigation of different exposure data sets and the estimation of asset values. Furthermore, we recommend the establishment of a reporting system in the municipalities for a fast identification of flood-affected objects shortly after an event.
KW  - rapid impact assessment
KW  - floods
KW  - OpenStreetMap
KW  - flood risk management
KW  - natural hazards
Y1  - 2022
U6  - https://doi.org/10.1088/1748-9326/ac6d6c
SN  - 1748-9326
VL  - 17
IS  - 6
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Deusdará-Leal, Karinne
A1  - Samprogna Mohor, Guilherme
A1  - Cuartas, Luz Adriana
A1  - Seluchi, Marcelo E.
A1  - Marengo, Jose A.
A1  - Zhang, Rong
A1  - Broedel, Elisangela
A1  - Amore, Diogo de Jesus
A1  - Alvalá, Regina C. S.
A1  - Cunha, Ana Paula M. A.
A1  - Gonçalves, José A. C.
T1  - Trends and climate elasticity of streamflow in south-eastern Brazil basins
JF  - Water
N2  - Trends in streamflow, rainfall and potential evapotranspiration (PET) time series, from 1970 to 2017, were assessed for five important hydrological basins in Southeastern Brazil. The concept of elasticity was also used to assess the streamflow sensitivity to changes in climate variables, for annual data and 5-, 10- and 20-year moving averages. Significant negative trends in streamflow and rainfall and significant increasing trend in PET were detected. For annual analysis, elasticity revealed that 1% decrease in rainfall resulted in 1.21-2.19% decrease in streamflow, while 1% increase in PET induced different reductions percentages in streamflow, ranging from 2.45% to 9.67%. When both PET and rainfall were computed to calculate the elasticity, results were positive for some basins. Elasticity analysis considering 20-year moving averages revealed that impacts on the streamflow were cumulative: 1% decrease in rainfall resulted in 1.83-4.75% decrease in streamflow, while 1% increase in PET induced 3.47-28.3% decrease in streamflow. This different temporal response may be associated with the hydrological memory of the basins. Streamflow appears to be more sensitive in less rainy basins. This study provides useful information to support strategic government decisions, especially when the security of water resources and drought mitigation are considered in face of climate change.
KW  - runoff
KW  - precipitation
KW  - potential evapotranspiration
KW  - Pettitt test
KW  - sensitivity
Y1  - 2022
U6  - https://doi.org/10.3390/w14142245
SN  - 2073-4441
VL  - 14
IS  - 14
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Thieken, Annegret
A1  - Mohor, Guilherme Samprogna
A1  - Kreibich, Heidi
A1  - Müller, Meike
T1  - Compound inland flood events
BT  - different pathways, different impacts and different coping options
JF  - Natural hazards and earth system sciences : NHESS
N2  - Several severe flood events hit Germany in recent years, with events in 2013 and 2016 being the most destructive ones, although dynamics and flood processes were very different. While the 2013 event was a slowly rising widespread fluvial flood accompanied by some severe dike breaches, the events in 2016 were fast-onset pluvial floods, which resulted in surface water flooding in some places due to limited capacities of the drainage systems and in destructive flash floods with high sediment loads and clogging in others, particularly in small steep catchments. Hence, different pathways, i.e. different routes that the water takes to reach (and potentially damage) receptors, in our case private households, can be identified in both events. They can thus be regarded as spatially compound flood events or compound inland floods. This paper analyses how differently affected residents coped with these different flood types (fluvial and pluvial) and their impacts while accounting for the different pathways (river flood, dike breach, surface water flooding and flash flood) within the compound events. The analyses are based on two data sets with 1652 (for the 2013 flood) and 601 (for the 2016 flood) affected residents who were surveyed around 9 months after each flood, revealing little socio-economic differences - except for income - between the two samples. The four pathways showed significant differences with regard to their hydraulic and financial impacts, recovery, warning processes, and coping and adaptive behaviour. There are just small differences with regard to perceived self-efficacy and responsibility, offering entry points for tailored risk communication and support to improve property-level adaptation.
Y1  - 2022
U6  - https://doi.org/10.5194/nhess-22-165-2022
SN  - 1561-8633
SN  - 1684-9981
VL  - 22
IS  - 1
SP  - 165
EP  - 185
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Rockström, Johan
T1  - Speeding up state-of-the-art assessments on global sustainability
BT  - introducing the Cambridge Sustainability Commissions
JF  - Global sustainability
Y1  - 2022
U6  - https://doi.org/10.1017/sus.2022.1
SN  - 2059-4798
VL  - 5
PB  - Cambridge University Press
CY  - Cambridge
ER  -