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  - 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  - 
TY  - JOUR
A1  - Fournier, Bertrand
A1  - Steiner, Magdalena
A1  - Brochet, Xavier
A1  - Degrune, Florine
A1  - Mammeri, Jibril
A1  - Carvalho, Diogo Leite
A1  - Siliceo, Sara Leal
A1  - Bacher, Sven
A1  - Peña-Reyes, Carlos Andrés
A1  - Heger, Thierry Jean
T1  - Toward the use of protists as bioindicators of multiple stresses in agricultural soils
BT  - a case study in vineyard ecosystems
JF  - Ecological indicators : integrating monitoring, assessment and management
N2  - Management of agricultural soil quality requires fast and cost-efficient methods to identify multiple stressors that can affect soil organisms and associated ecological processes. Here, we propose to use soil protists which have a great yet poorly explored potential for bioindication. They are ubiquitous, highly diverse, and respond to various stresses to agricultural soils caused by frequent management or environmental changes. We test an approach that combines metabarcoding data and machine learning algorithms to identify potential stressors of soil protist community composition and diversity. We measured 17 key variables that reflect various potential stresses on soil protists across 132 plots in 28 Swiss vineyards over 2 years. We identified the taxa showing strong responses to the selected soil variables (potential bioindicator taxa) and tested for their predictive power. Changes in protist taxa occurrence and, to a lesser extent, diversity metrics exhibited great predictive power for the considered soil variables. Soil copper concentration, moisture, pH, and basal respiration were the best predicted soil variables, suggesting that protists are particularly responsive to stresses caused by these variables. The most responsive taxa were found within the clades Rhizaria and Alveolata. Our results also reveal that a majority of the potential bioindicators identified in this study can be used across years, in different regions and across different grape varieties. Altogether, soil protist metabarcoding data combined with machine learning can help identifying specific abiotic stresses on microbial communities caused by agricultural management. Such an approach provides complementary information to existing soil monitoring tools that can help manage the impact of agricultural practices on soil biodiversity and quality.
KW  - Biomonitoring
KW  - Machine learning
KW  - Predictive model
KW  - Soil function
KW  - Soil
KW  - quality
KW  - Microbial ecology
Y1  - 2022
U6  - https://doi.org/10.1016/j.ecolind.2022.108955
SN  - 1470-160X
SN  - 1872-7034
VL  - 139
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wutzler, Bianca
A1  - Hudson, Paul
A1  - Thieken, Annegret
T1  - Adaptation strategies of flood-damaged businesses in Germany
JF  - Frontiers in Water
N2  - Flood risk management in Germany follows an integrative approach in which both private households and businesses can make an important contribution to reducing flood damage by implementing property-level adaptation measures. While the flood adaptation behavior of private households has already been widely researched, comparatively less attention has been paid to the adaptation strategies of businesses. However, their ability to cope with flood risk plays an important role in the social and economic development of a flood-prone region. Therefore, using quantitative survey data, this study aims to identify different strategies and adaptation drivers of 557 businesses damaged by a riverine flood in 2013 and 104 businesses damaged by pluvial or flash floods between 2014 and 2017. Our results indicate that a low perceived self-efficacy may be an important factor that can reduce the motivation of businesses to adapt to flood risk. Furthermore, property-owners tended to act more proactively than tenants. In addition, high experience with previous flood events and low perceived response costs could strengthen proactive adaptation behavior. These findings should be considered in business-tailored risk communication.
KW  - risk management
KW  - climate change adaptation
KW  - floods
KW  - disaster risk reduction
KW  - Germany
KW  - precaution
KW  - emergency management
Y1  - 2022
U6  - https://doi.org/10.3389/frwa.2022.932061
SN  - 2624-9375
PB  - Frontiers Media SA
CY  - Lausanne, Schweiz
ER  - 
TY  - JOUR
A1  - Müller, Sebastian
A1  - Schüler, Lennart
A1  - Zech, Alraune
A1  - Heße, Falk
T1  - GSTools v1.3: a toolbox for geostatistical modelling in Python
JF  - Geoscientific model development : an interactive open access journal of the European Geosciences Union
N2  - Geostatistics as a subfield of statistics accounts for the spatial correlations encountered in many applications of, for example, earth sciences. Valuable information can be extracted from these correlations, also helping to address the often encountered burden of data scarcity. Despite the value of additional data, the use of geostatistics still falls short of its potential. This problem is often connected to the lack of user-friendly software hampering the use and application of geostatistics. We therefore present GSTools, a Python-based software suite for solving a wide range of geostatistical problems. We chose Python due to its unique balance between usability, flexibility, and efficiency and due to its adoption in the scientific community. GSTools provides methods for generating random fields; it can perform kriging, variogram estimation and much more. We demonstrate its abilities by virtue of a series of example applications detailing their use.
Y1  - 2022
U6  - https://doi.org/10.5194/gmd-15-3161-2022
SN  - 1991-959X
SN  - 1991-9603
VL  - 15
IS  - 7
SP  - 3161
EP  - 3182
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Bauer, Jonas
A1  - Börsig, Nicolas
A1  - Pham, Van Cam
A1  - Hoan, Tran Viet
A1  - Nguyen, Ha Thi
A1  - Norra, Stefan
T1  - Geochemistry and evolution of groundwater resources in the context of salinization and freshening in the southernmost Mekong Delta, Vietnam
JF  - Journal of Hydrology: Regional Studies
N2  - Study region: 
Ca Mau Province (CMP), Mekong Delta (MD), Vietnam. 

Study focus: 
Groundwater from deep aquifers is the most reliable source of freshwater in the MD but extensive overexploitation in the last decades led to the drop of hydraulic heads and negative environmental impacts. Therefore, a comprehensive groundwater investigation was conducted to evaluate its composition in the context of Quaternary marine transgression and regression cycles, geochemical processes as well as groundwater extraction. 

New hydrological insights for the region: 
The abundance of groundwater of Na-HCO3 type and distinct ion ratios, such as Na+/Cl-, indicate extensive freshwater intrusion in an initially saline hydrogeological system, with decreasing intensity from upper Pleistocene to deeper Miocene aquifers, most likely during the last marine regression phase 60-12 ka BP. Deviations from the conservative mixing line between the two endmembers seawater and freshwater are attributed to ion-exchange processes on mineral surfaces, making ion ratios in combination with a customized water type analysis a useful tool to distinguish between salinization and freshening processes. Elevated salinity in some areas is attributed to HCO3- generation by organic matter decomposition in marine sediments rather than to seawater intrusion. Nevertheless, a few randomly distributed locations show strong evidence of recent salinization in an early stage, which may be caused by the downwards migration of saline Holocene groundwater through natural and anthropogenic pathways into deep aquifers.
KW  - Ca Mau
KW  - Hydrogeology
KW  - Delta aquifer system
KW  - Salinity
KW  - Freshwater
KW  - Seawater intrusion
Y1  - 2022
U6  - https://doi.org/10.1016/j.ejrh.2022.101010
SN  - 2214-5818
VL  - 40
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Puppe, Daniel
A1  - Leue, Martin
A1  - Sommer, Michael
A1  - Schaller, Jörg
A1  - Kaczorek, Danuta
T1  - Auto-fluorescence in phytoliths
BT  - a mechanistic understanding derived from microscopic and spectroscopic analyses
JF  - Frontiers in Environmental Science
N2  - The detection of auto-fluorescence in phytogenic, hydrated amorphous silica depositions (phytoliths) has been found to be a promising approach to verify if phytoliths were burnt or not, especially in archaeological contexts. However, it is unknown so far at what temperature and how auto-fluorescence is induced in phytoliths. We used fluorescence microscopy, scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDX), and Fourier transform infrared spectroscopy to analyze auto-fluorescence in modern phytoliths extracted from plant samples or in intact leaves of winter wheat. Leaves and extracted phytoliths were heated at different temperatures up to 600 degrees C. The aims of our experiments were i) to find out what temperature is needed to induce auto-fluorescence in phytoliths, ii) to detect temperature-dependent changes in the molecular structure of phytoliths related to auto-fluorescence, and iii) to derive a mechanistic understanding of auto-fluorescence in phytoliths. We found organic compounds associated with phytoliths to cause auto-fluorescence in phytoliths treated at temperatures below approx. 400 degrees C. In phytoliths treated at higher temperatures, i.e., 450 and 600 degrees C, phytolith auto-fluorescence was mainly caused by molecular changes of phytolith silica. Based on our results we propose that auto-fluorescence in phytoliths is caused by clusterization-triggered emissions, which are caused by overlapping electron clouds forming non-conventional chromophores. In phytoliths heated at temperatures above about 400 degrees C dihydroxylation and the formation of siloxanes result in oxygen clusters that serve as non-conventional chromophores in fluorescence events. Furthermore, SEM-EDX analyses revealed that extractable phytoliths were dominated by lumen phytoliths (62%) compared to cell wall phytoliths (38%). Our findings might be not only relevant in archaeological phytolith-based examinations, but also for studies on the temperature-dependent release of silicon from phytoliths and the potential of long-term carbon sequestration in phytoliths.
KW  - fluorescence microscopy
KW  - FTIR spectroscopy
KW  - SEM-EDX
KW  - burnt phytoliths;
KW  - carbon sequestration
Y1  - 2022
U6  - https://doi.org/10.3389/fenvs.2022.915947
SN  - 2296-665X
VL  - 10
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Athare, Tushar Ramchandra
A1  - Pradhan, Prajal
A1  - Singh, S. R. K.
A1  - Kropp, Jürgen
T1  - India consists of multiple food systems with scoioeconomic and environmental variations
JF  - PLOS ONE / Public Library of Science
N2  - Agriculture in India accounts for 18% of greenhouse gas (GHG) emissions and uses significant land and water. Various socioeconomic factors and food subsidies influence diets in India. Indian food systems face the challenge of sustainably nourishing the 1.3 billion population. However, existing studies focus on a few food system components, and holistic analysis is still missing. We identify Indian food systems covering six food system components: food consumption, production, processing, policy, environmental footprints, and socioeconomic factors from the latest Indian household consumer expenditure survey. We identify 10 Indian food systems using k-means cluster analysis on 15 food system indicators belonging to the six components. Based on the major source of calorie intake, we classify the ten food systems into production-based (3), subsidy-based (3), and market-based (4) food systems. Home-produced and subsidized food contribute up to 2000 kcal/consumer unit (CU)/day and 1651 kcal/CU/day, respectively, in these food systems. The calorie intake of 2158 to 3530 kcal/CU/day in the food systems reveals issues of malnutrition in India. Environmental footprints are commensurate with calorie intake in the food systems. Embodied GHG, land footprint, and water footprint estimates range from 1.30 to 2.19 kg CO(2)eq/CU/day, 3.89 to 6.04 m(2)/CU/day, and 2.02 to 3.16 m(3)/CU/day, respectively. Our study provides a holistic understanding of Indian food systems for targeted nutritional interventions on household malnutrition in India while also protecting planetary health.
Y1  - 2022
U6  - https://doi.org/10.1371/journal.pone.0270342
SN  - 1932-6203
VL  - 17
IS  - 8
PB  - PLoS
CY  - San Fransisco
ER  - 
TY  - JOUR
A1  - Khurana, Swamini
A1  - Hesse, Falk
A1  - Kleidon-Hildebrandt, Anke
A1  - Thullner, Martin
T1  - Should we worry about surficial dynamics when assessing nutrient cycling in the groundwater?
JF  - Frontiers in water
N2  - The fluxes of water and solutes in the subsurface compartment of the Critical Zone are temporally dynamic and it is unclear how this impacts microbial mediated nutrient cycling in the spatially heterogeneous subsurface. To investigate this, we undertook numerical modeling, simulating the transport in a wide range of spatially heterogeneous domains, and the biogeochemical transformation of organic carbon and nitrogen compounds using a complex microbial community with four (4) distinct functional groups, in water saturated subsurface compartments. We performed a comprehensive uncertainty analysis accounting for varying residence times and spatial heterogeneity. While the aggregated removal of chemical species in the domains over the entire simulation period was approximately the same as that in steady state conditions, the sub-scale temporal variation of microbial biomass and chemical discharge from a domain depended strongly on the interplay of spatial heterogeneity and temporal dynamics of the forcing. We showed that the travel time and the Damkohler number (Da) can be used to predict the temporally varying chemical discharge from a spatially heterogeneous domain. In homogeneous domains, chemical discharge in temporally dynamic conditions could be double of that in the steady state conditions while microbial biomass varied up to 75% of that in steady state conditions. In heterogeneous domains, the interquartile range of uncertainty in chemical discharge in reaction dominated systems (log(10)Da > 0) was double of that in steady state conditions. However, high heterogeneous domains resulted in outliers where chemical discharge could be as high as 10-20 times of that in steady state conditions in high flow periods. And in transport dominated systems (log(10)Da < 0), the chemical discharge could be half of that in steady state conditions in unusually low flow conditions. In conclusion, ignoring spatio-temporal heterogeneities in a numerical modeling approach may exacerbate inaccurate estimation of nutrient export and microbial biomass. The results are relevant to long-term field monitoring studies, and for homogeneous soil column-scale experiments investigating the role of temporal dynamics on microbial redox dynamics.
KW  - reactive transport modeling
KW  - spatio-temporal heterogeneity
KW  - uncertainty
KW  - geomicrobial activity
KW  - nutrient export
Y1  - 2022
U6  - https://doi.org/10.3389/frwa.2022.780297
SN  - 2624-9375
VL  - 4
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Siegmund, Nicole
A1  - Panebianco, Juan E.
A1  - Avecilla, Fernando
A1  - Iturri, Laura Antonela
A1  - Sommer, Michael
A1  - Buschiazzo, Daniel
A1  - Funk, Roger
T1  - From gustiness to dustiness
BT  - the impact of wind gusts on particulate matter emissions in field experiments in La Pampa, Argentina
JF  - Atmosphere
N2  - This study delivers the first empirical data-driven analysis of the impact of turbulence induced gustiness on the fine dust emissions from a measuring field. For quantification of the gust impact, a new measure, the Gust uptake Efficiency (GuE) is introduced. GuE provides a percentage of over- or under-proportional dust uptake due to gust activity during a wind event. For the three analyzed wind events, GuE values of up to 150% could be found, yet they significantly differed per particle size class with a tendency for lower values for smaller particles. In addition, a high-resolution correlation analysis among 31 particle size classes and wind speed was conducted; it revealed strong negative correlation coefficients for very small particles and positive correlations for bigger particles, where 5 mu m appears to be an empirical threshold dividing both directions. We conclude with a number of suggestions for further investigations: an optimized field experiment setup, a new particle size ratio (PM1/PM0.5 in addition to PM10/PM2.5), as well as a comprehensive data-driven search for an optimal wind gust definition in terms of soil erosivity.
KW  - wind gusts
KW  - wind erosion
KW  - particle uptake
KW  - dust plumes
Y1  - 2022
U6  - https://doi.org/10.3390/atmos13081173
SN  - 2073-4433
VL  - 13
IS  - 8
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Hoan, Tran Viet
A1  - Richter, Karl-Gerd
A1  - Borsig, Nicolas
A1  - Bauer, Jonas
A1  - Ha, Nguyen Thi
A1  - Norra, Stefan
T1  - An improved groundwater model framework for aquifer structures of the quaternary-formed sediment body in the southernmost parts of the Mekong Delta, Vietnam
JF  - Hydrology : open access journal
N2  - The Ca Mau peninsula (CMP) is a key economic region in southern Vietnam. In recent decades, the high demand for water has increased the exploitation of groundwater, thus lowering the groundwater level and leading to risks of degradation, depletion, and land subsidence, as well as salinity intrusion in the groundwater of the whole Mekong Delta region. By using a finite element groundwater model with boundary expansion to the sea, we updated the latest data on hydrogeological profiles, groundwater levels, and exploitation. The basic model setup covers seven aquifers and seven aquitards. It is determined that the inflow along the coastline to the mainland is 39% of the total inflow. The exploitation of the study area in 2019 was 567,364 m(3)/day. The most exploited aquifers are the upper-middle Pleistocene (qp(2-3)) and the middle Pliocene (n(2)(2)), accounting for 63.7% and 24.6%, respectively; the least exploited aquifers are the upper Pleistocene and the upper Miocene, accounting for 0.35% and 0.02%, respectively. In the deeper aquifers, qp(2-3) and n(2)(2), the change in storage is negative due to the high exploitation rate, leading to a decline in the reserves of these aquifers. These groundwater model results are the calculations of groundwater reserves from the coast to the mainland in the entire system of aquifers in the CMP. This makes groundwater decision managers, stakeholders, and others more efficient in sustainable water resources planning in the CMP and Mekong Delta (MKD).
KW  - groundwater modeling
KW  - hydrogeology
KW  - aquifers system
KW  - water balance;
KW  - validation of model
KW  - Ca Mau peninsula
KW  - Kien Giang
KW  - Soc Trang
KW  - Hau Giang
KW  - Bac Lieu
Y1  - 2022
U6  - https://doi.org/10.3390/hydrology9040061
SN  - 2306-5338
VL  - 9
IS  - 4
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Reinecke, Robert
A1  - Trautmann, Tim
A1  - Wagener, Thorsten
A1  - Schüler, Katja
T1  - The critical need to foster computational reproducibility
JF  - Environmental research letters
KW  - reproducibility
KW  - models
KW  - software
KW  - Open Science
Y1  - 2022
U6  - https://doi.org/10.1088/1748-9326/ac5cf8
SN  - 1748-9326
VL  - 17
IS  - 4
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Seleem, Omar
A1  - Ayzel, Georgy
A1  - Costa Tomaz de Souza, Arthur
A1  - Bronstert, Axel
A1  - Heistermann, Maik
T1  - Towards urban flood susceptibility mapping using data-driven models in Berlin, Germany
JF  - Geomatics, natural hazards and risk
N2  - Identifying urban pluvial flood-prone areas is necessary but the application of two-dimensional hydrodynamic models is limited to small areas. Data-driven models have been showing their ability to map flood susceptibility but their application in urban pluvial flooding is still rare. A flood inventory (4333 flooded locations) and 11 factors which potentially indicate an increased hazard for pluvial flooding were used to implement convolutional neural network (CNN), artificial neural network (ANN), random forest (RF) and support vector machine (SVM) to: (1) Map flood susceptibility in Berlin at 30, 10, 5, and 2 m spatial resolutions. (2) Evaluate the trained models' transferability in space. (3) Estimate the most useful factors for flood susceptibility mapping. The models' performance was validated using the Kappa, and the area under the receiver operating characteristic curve (AUC). The results indicated that all models perform very well (minimum AUC = 0.87 for the testing dataset). The RF models outperformed all other models at all spatial resolutions and the RF model at 2 m spatial resolution was superior for the present flood inventory and predictor variables. The majority of the models had a moderate performance for predictions outside the training area based on Kappa evaluation (minimum AUC = 0.8). Aspect and altitude were the most influencing factors on the image-based and point-based models respectively. Data-driven models can be a reliable tool for urban pluvial flood susceptibility mapping wherever a reliable flood inventory is available.
KW  - Urban pluvial flood susceptibility
KW  - convolutional neural network
KW  - deep
KW  - learning
KW  - random forest
KW  - support vector machine
KW  - spatial resolution;
KW  - flood predictors
Y1  - 2022
U6  - https://doi.org/10.1080/19475705.2022.2097131
SN  - 1947-5705
SN  - 1947-5713
VL  - 13
IS  - 1
SP  - 1640
EP  - 1662
PB  - Taylor & Francis
CY  - London
ER  - 
TY  - JOUR
A1  - Mtilatila, Lucy Mphatso Ng'ombe
A1  - Bronstert, Axel
A1  - Vormoor, Klaus Josef
T1  - Temporal evaluation and projections of meteorological droughts in the Greater Lake Malawi Basin, Southeast Africa
JF  - Frontiers in water
N2  - The study examined the potential future changes of drought characteristics in the Greater Lake Malawi Basin in Southeast Africa. This region strongly depends on water resources to generate electricity and food. Future projections (considering both moderate and high emission scenarios) of temperature and precipitation from an ensemble of 16 bias-corrected climate model combinations were blended with a scenario-neutral response surface approach to analyses changes in: (i) the meteorological conditions, (ii) the meteorological water balance, and (iii) selected drought characteristics such as drought intensity, drought months, and drought events, which were derived from the Standardized Precipitation and Evapotranspiration Index. Changes were analyzed for a near-term (2021-2050) and far-term period (2071-2100) with reference to 1976-2005. The effect of bias-correction (i.e., empirical quantile mapping) on the ability of the climate model ensemble to reproduce observed drought characteristics as compared to raw climate projections was also investigated. Results suggest that the bias-correction improves the climate models in terms of reproducing temperature and precipitation statistics but not drought characteristics. Still, despite the differences in the internal structures and uncertainties that exist among the climate models, they all agree on an increase of meteorological droughts in the future in terms of higher drought intensity and longer events. Drought intensity is projected to increase between +25 and +50% during 2021-2050 and between +131 and +388% during 2071-2100. This translates into +3 to +5, and +7 to +8 more drought months per year during both periods, respectively. With longer lasting drought events, the number of drought events decreases. Projected droughts based on the high emission scenario are 1.7 times more severe than droughts based on the moderate scenario. That means that droughts in this region will likely become more severe in the coming decades. Despite the inherent high uncertainties of climate projections, the results provide a basis in planning and (water-)managing activities for climate change adaptation measures in Malawi. This is of particular relevance for water management issues referring hydro power generation and food production, both for rain-fed and irrigated agriculture.
KW  - meteorological drought
KW  - drought intensity
KW  - climate change
KW  - drought
KW  - events
KW  - Lake Malawi
KW  - Shire River
KW  - drought projections
KW  - South-Eastern
KW  - Africa
Y1  - 2022
U6  - https://doi.org/10.3389/frwa.2022.1041452
SN  - 2624-9375
VL  - 4
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Mtilatila, Lucy Mphatso Ng'ombe
A1  - Bronstert, Axel
A1  - Vormoor, Klaus Josef
T1  - Temporal evaluation and projections of meteorological droughts in the Greater Lake Malawi Basin, Southeast Africa
JF  - Frontiers in Water
N2  - The study examined the potential future changes of drought characteristics in the Greater Lake Malawi Basin in Southeast Africa. This region strongly depends on water resources to generate electricity and food. Future projections (considering both moderate and high emission scenarios) of temperature and precipitation from an ensemble of 16 bias-corrected climate model combinations were blended with a scenario-neutral response surface approach to analyses changes in: (i) the meteorological conditions, (ii) the meteorological water balance, and (iii) selected drought characteristics such as drought intensity, drought months, and drought events, which were derived from the Standardized Precipitation and Evapotranspiration Index. Changes were analyzed for a near-term (2021–2050) and far-term period (2071–2100) with reference to 1976–2005. The effect of bias-correction (i.e., empirical quantile mapping) on the ability of the climate model ensemble to reproduce observed drought characteristics as compared to raw climate projections was also investigated. Results suggest that the bias-correction improves the climate models in terms of reproducing temperature and precipitation statistics but not drought characteristics. Still, despite the differences in the internal structures and uncertainties that exist among the climate models, they all agree on an increase of meteorological droughts in the future in terms of higher drought intensity and longer events. Drought intensity is projected to increase between +25 and +50% during 2021–2050 and between +131 and +388% during 2071–2100. This translates into +3 to +5, and +7 to +8 more drought months per year during both periods, respectively. With longer lasting drought events, the number of drought events decreases. Projected droughts based on the high emission scenario are 1.7 times more severe than droughts based on the moderate scenario. That means that droughts in this region will likely become more severe in the coming decades. Despite the inherent high uncertainties of climate projections, the results provide a basis in planning and (water-)managing activities for climate change adaptation measures in Malawi. This is of particular relevance for water management issues referring hydro power generation and food production, both for rain-fed and irrigated agriculture.
KW  - meteorological drought
KW  - drought intensity
KW  - climate change
KW  - drought events
KW  - Lake Malawi
KW  - Shire River
KW  - drought projections
KW  - South-Eastern Africa
Y1  - 2022
U6  - https://doi.org/10.3389/frwa.2022.1041452
SN  - 2624-9375
SP  - 1
EP  - 16
PB  - Frontiers Media S.A.
CY  - Lausanne, Schweiz
ER  - 
TY  - JOUR
A1  - Bryant, Seth
A1  - McGrath, Heather
A1  - Boudreault, Mathieu
T1  - Gridded flood depth estimates from satellite-derived inundations
JF  - Natural hazards and earth system sciences
N2  - Canada's RADARSAT missions improve the potential to study past flood events; however, existing tools to derive flood depths from this remote-sensing data do not correct for errors, leading to poor estimates. 
To provide more accurate gridded depth estimates of historical flooding, a new tool is proposed that integrates Height Above Nearest Drainage and Cost Allocation algorithms. This tool is tested against two trusted, hydraulically derived, gridded depths of recent floods in Canada. 
This validation shows the proposed tool outperforms existing tools and can provide more accurate estimates from minimal data without the need for complex physics-based models or expert judgement. 
With improvements in remote-sensing data, the tool proposed here can provide flood researchers and emergency managers accurate depths in near-real time.
Y1  - 2022
U6  - https://doi.org/10.5194/nhess-22-1437-2022
SN  - 1561-8633
SN  - 1684-9981
VL  - 22
IS  - 4
SP  - 1437
EP  - 1450
PB  - European Geophysical Society
CY  - Katlenburg-Lindau
ER  - 
TY  - JOUR
A1  - Kühn, Elisabeth
A1  - Becker, Marc
A1  - Harpke, Alexander
A1  - Kühn, Ingolf
A1  - Kuhlicke, Christian
A1  - Schmitt, Thomas
A1  - Settele, Josef
A1  - Musche, Martin
T1  - The benefits of counting butterflies: recommendations for a successful citizen science project
JF  - Ecology and Society
N2  - Citizen science (CS) projects, being popular across many fields of science, have recently also become a popular tool to collect biodiversity data. Although the benefits of such projects for science and policy making are well understood, relatively little is known about the benefits participants get from these projects as well as their personal backgrounds and motivations. Furthermore, very little is known about their expectations. We here examine these aspects, with the citizen science project "German Butterfly Monitoring" as an example. A questionnaire was sent to all participants of the project and the responses to the questionnaire indicated the following: center dot Most transect walkers do not have a professional background in this field, though they do have a high educational level, and are close to retirement, with a high number of females; center dot An important motivation to join the project is to preserve the natural environment and to contribute to scientific knowledge; center dot Participants benefit by enhancing their knowledge about butterflies and especially their ability to identify different species (taxonomic knowledge); center dot Participants do not have specific expectations regarding the project beyond proper management and coordination, but have an intrinsic sense of working for a greater good. The willingness to join a project is higher if the project contributes to the solution of a problem discussed in the media (here, insect decline). Based on our findings from the analysis of the questionnaire we can derive a set of recommendations for establishing a successful CS project. These include the importance of good communication, e.g., by explaining what the (scientific) purpose of the project is and what problems are to be solved with the help of the data collected in the project. The motivation to join a CS project is mostly intrinsic and CS is a good tool to engage people during difficult times such as the COVID-19 pandemic, giving participants the feeling of doing something useful.
KW  - COVID-19 pandemic
KW  - gender gap
KW  - insect decline
KW  - intrinsic motivation
KW  - monitoring
Y1  - 2022
U6  - https://doi.org/10.5751/ES-12861-270238
SN  - 1708-3087
VL  - 27
IS  - 2
PB  - Resilience Alliance
CY  - Wolfville
ER  - 
TY  - JOUR
A1  - Schweppe, Robert
A1  - Thober, Stephan
A1  - Müller, Sebastian
A1  - Kelbling, Matthias
A1  - Kumar, Rohini
A1  - Attinger, Sabine
A1  - Samaniego, Luis
T1  - MPR 1.0: a stand-alone multiscale parameter regionalization tool for improved parameter estimation of land surface models
JF  - Geoscientific model development : an interactive open access journal of the European Geosciences Union
N2  - Distributed environmental models such as land surface models (LSMs) require model parameters in each spatial modeling unit (e.g., grid cell), thereby leading to a high-dimensional parameter space. One approach to decrease the dimensionality of the parameter space in these models is to use regularization techniques. One such highly efficient technique is the multiscale parameter regionalization (MPR) framework that translates high-resolution predictor variables (e.g., soil textural properties) into model parameters (e.g., porosity) via transfer functions (TFs) and upscaling operators that are suitable for every modeled process. This framework yields seamless model parameters at multiple scales and locations in an effective manner. However, integration of MPR into existing modeling workflows has been hindered thus far by hard-coded configurations and non-modular software designs. For these reasons, we redesigned MPR as a model-agnostic, stand-alone tool. It is a useful software for creating graphs of NetCDF variables, wherein each node is a variable and the links consist of TFs and/or upscaling operators. In this study, we present and verify our tool against a previous version, which was implemented in the mesoscale hydrologic model (mHM; https://www.ufz.de/mhm, last access: 16 January 2022). By using this tool for the generation of continental-scale soil hydraulic parameters applicable to different models (Noah-MP and HTESSEL), we showcase its general functionality and flexibility. Further, using model parameters estimated by the MPR tool leads to significant changes in long-term estimates of evapotranspiration, as compared to their default parameterizations. For example, a change of up to 25 % in long-term evapotranspiration flux is observed in Noah-MP and HTESSEL in the Mississippi River basin. We postulate that use of the stand-alone MPR tool will considerably increase the transparency and reproducibility of the parameter estimation process in distributed (environmental) models. It will also allow a rigorous uncertainty estimation related to the errors of the predictors (e.g., soil texture fields), transfer function and its parameters, and remapping (or upscaling) algorithms.
Y1  - 2022
U6  - https://doi.org/10.5194/gmd-15-859-2022
SN  - 1991-959X
SN  - 1991-9603
VL  - 15
IS  - 2
SP  - 859
EP  - 882
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Funk, Roger
A1  - Busse, Jaqueline
A1  - Siegmund, Nicole
A1  - Sommer, Michael
A1  - Iturri, Laura Antonela
A1  - Panebianco, Juan E.
A1  - Avecilla, Fernando
A1  - Buschiazzo, Daniel
T1  - Phytoliths in particulate matter released by wind erosion on arable land in La Pampa, Argentina
JF  - Frontiers in environmental science
N2  - Silicon (Si) is considered a beneficial element in plant nutrition, but its importance on ecosystems goes far beyond that. Various forms of silicon are found in soils, of which the phytogenic pool plays a decisive role due to its good availability. This Si returns to the soil through the decomposition of plant residues, where they then participate in the further cycle as biogenic amorphous silica (bASi) or so-called phytoliths. These have a high affinity for water, so that the water holding capacity and water availability of soils can be increased even by small amounts of ASi. Agricultural land is a considerable global dust source, and dust samples from arable land have shown in cloud formation experiments a several times higher ice nucleation activity than pure mineral dust. Here, particle sizes in the particulate matter fractions (PM) are important, which can travel long distances and reach high altitudes in the atmosphere. Based on this, the research question was whether phytoliths could be detected in PM samples from wind erosion events, what are the main particle sizes of phytoliths and whether an initial quantification was possible.Measurements of PM concentrations were carried out at a wind erosion measuring field in the province La Pampa, Argentina. PM were sampled during five erosion events with Environmental Dust Monitors (EDM). After counting and classifying all particles with diameters between 0.3 and 32 mu m in the EDMs, they are collected on filters. The filters were analyzed by Scanning Electron Microscopy and Energy Dispersive X-Ray analysis (SEM-EDX) to investigate single or ensembles of particles regarding composition and possible origins.The analyses showed up to 8.3 per cent being phytoliths in the emitted dust and up to 25 per cent of organic origin. Particles of organic origin are mostly in the coarse dust fraction, whereas phytoliths are predominately transported in the finer dust fractions. Since phytoliths are both an important source of Si as a plant nutrient and are also involved in soil C fixation, their losses from arable land via dust emissions should be considered and its specific influence on atmospheric processes should be studied in detail in the future.
KW  - dust
KW  - dust composition
KW  - particulate matter
KW  - scanning electron microscope
KW  - (SEM) analysis
KW  - phytolith
Y1  - 2022
U6  - https://doi.org/10.3389/fenvs.2022.969898
SN  - 2296-665X
VL  - 10
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Francke, Till
A1  - Heistermann, Maik
A1  - Köhli, Markus
A1  - Budach, Christian
A1  - Schrön, Martin
A1  - Oswald, Sascha
T1  - Assessing the feasibility of a directional cosmic-ray neutron sensing sensor for estimating soil moisture
JF  - Geoscientific Instrumentation, Methods and Data Systems
N2  - Cosmic-ray neutron sensing (CRNS) is a non-invasive tool for measuring hydrogen pools such as soil moisture, snow or vegetation. The intrinsic integration over a radial hectare-scale footprint is a clear advantage for averaging out small-scale heterogeneity, but on the other hand the data may become hard to interpret in complex terrain with patchy land use.

This study presents a directional shielding approach to prevent neutrons from certain angles from being counted while counting neutrons entering the detector from other angles and explores its potential to gain a sharper horizontal view on the surrounding soil moisture distribution.

Using the Monte Carlo code URANOS (Ultra Rapid Neutron-Only Simulation), we modelled the effect of additional polyethylene shields on the horizontal field of view and assessed its impact on the epithermal count rate, propagated uncertainties and aggregation time.

The results demonstrate that directional CRNS measurements are strongly dominated by isotropic neutron transport, which dilutes the signal of the targeted direction especially from the far field. For typical count rates of customary CRNS stations, directional shielding of half-spaces could not lead to acceptable precision at a daily time resolution. However, the mere statistical distinction of two rates should be feasible.
KW  - water-balance
KW  - quantification
KW  - calibration
KW  - validation
Y1  - 2021
U6  - https://doi.org/10.5194/gi-11-75-2022
SN  - 2193-0864
SN  - 2193-0856
VL  - 11
SP  - 75
EP  - 92
PB  - Copernicus Publ.
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Pánek, Tomáš
A1  - Břežný, Michal
A1  - Harrison, Stephan
A1  - Schönfeldt, Elisabeth
A1  - Winocur, Diego
T1  - Large landslides cluster at the margin of a deglaciated mountain belt
JF  - Scientific reports
N2  - Landslides in deglaciated and deglaciating mountains represent a major hazard, but their distribution at the spatial scale of entire mountain belts has rarely been studied. Traditional models of landslide distribution assume that landslides are concentrated in the steepest, wettest, and most tectonically active parts of the orogens, where glaciers reached their greatest thickness. 
However, based on mapping large landslides (>0.9 km(2)) over an unprecedentedly large area of Southern Patagonia (similar to 305,000 km(2)), we show that the distribution of landslides can have the opposite trend. 
We show that the largest landslides within the limits of the former Patagonian Ice Sheet (PIS) cluster along its eastern margins occupying lower, tectonically less active, and arid part of the Patagonian Andes. In contrast to the heavily glaciated, highest elevations of the mountain range, the peripheral regions have been glaciated only episodically, leaving a larger volume of unstable sedimentary and volcanic rocks that are subject to ongoing slope instability.
Y1  - 2022
U6  - https://doi.org/10.1038/s41598-022-09357-9
SN  - 2045-2322
VL  - 12
IS  - 1
PB  - Macmillan Publishers Limited, part of Springer Nature
CY  - London
ER  - 
TY  - JOUR
A1  - Trautmann, Tina
A1  - Koirala, Sujan
A1  - Carvalhais, Nuno
A1  - Güntner, Andreas
A1  - Jung, Martin
T1  - The importance of vegetation in understanding terrestrial water storage variations
JF  - Hydrology and Earth System Sciences
N2  - So far, various studies have aimed at decomposing the integrated terrestrial water storage variations observed by satellite gravimetry (GRACE, GRACE-FO) with the help of large-scale hydrological models. While the results of the storage decomposition depend on model structure, little attention has been given to the impact of the way that vegetation is represented in these models. Although vegetation structure and activity represent the crucial link between water, carbon, and energy cycles, their representation in large-scale hydrological models remains a major source of uncertainty. At the same time, the increasing availability and quality of Earth-observation-based vegetation data provide valuable information with good prospects for improving model simulations and gaining better insights into the role of vegetation within the global water cycle. In this study, we use observation-based vegetation information such as vegetation indices and rooting depths for spatializing the parameters of a simple global hydrological model to define infiltration, root water uptake, and transpiration processes. The parameters are further constrained by considering observations of terrestrial water storage anomalies (TWS), soil moisture, evapotranspiration (ET) and gridded runoff ( Q) estimates in a multi-criteria calibration approach. We assess the implications of including varying vegetation characteristics on the simulation results, with a particular focus on the partitioning between water storage components. To isolate the effect of vegetation, we compare a model experiment in which vegetation parameters vary in space and time to a baseline experiment in which all parameters are calibrated as static, globally uniform values. Both experiments show good overall performance, but explicitly including varying vegetation data leads to even better performance and more physically plausible parameter values. The largest improvements regarding TWS and ET are seen in supply-limited (semi-arid) regions and in the tropics, whereas Q simulations improve mainly in northern latitudes. While the total fluxes and storages are similar, accounting for vegetation substantially changes the contributions of different soil water storage components to the TWS variations. This suggests an important role of the representation of vegetation in hydrological models for interpreting TWS variations. Our simulations further indicate a major effect of deeper moisture storages and groundwater-soil moisture-vegetation interactions as a key to understanding TWS variations. We highlight the need for further observations to identify the adequate model structure rather than only model parameters for a reasonable representation and interpretation of vegetation-water interactions.
Y1  - 2022
U6  - https://doi.org/10.5194/hess-26-1089-2022
SN  - 1027-5606
SN  - 1607-7938
VL  - 26
IS  - 4
SP  - 1089
EP  - 1109
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Veh, Georg
A1  - Lützow, Natalie
A1  - Kharlamova, Varvara
A1  - Petrakov, Dmitry
A1  - Hugonnet, Romain
A1  - Korup, Oliver
T1  - Trends, breaks, and biases in the frequency of reported glacier lake outburst floods
JF  - Earth's future
N2  - Thousands of glacier lakes have been forming behind natural dams in high mountains following glacier retreat since the early 20th century. Some of these lakes abruptly released pulses of water and sediment with disastrous downstream consequences. Yet it remains unclear whether the reported rise of these glacier lake outburst floods (GLOFs) has been fueled by a warming atmosphere and enhanced meltwater production, or simply a growing research effort. Here we estimate trends and biases in GLOF reporting based on the largest global catalog of 1,997 dated glacier-related floods in six major mountain ranges from 1901 to 2017. We find that the positive trend in the number of reported GLOFs has decayed distinctly after a break in the 1970s, coinciding with independently detected trend changes in annual air temperatures and in the annual number of field-based glacier surveys (a proxy of scientific reporting). We observe that GLOF reports and glacier surveys decelerated, while temperature rise accelerated in the past five decades. Enhanced warming alone can thus hardly explain the annual number of reported GLOFs, suggesting that temperature-driven glacier lake formation, growth, and failure are weakly coupled, or that outbursts have been overlooked. Indeed, our analysis emphasizes a distinct geographic and temporal bias in GLOF reporting, and we project that between two to four out of five GLOFs on average might have gone unnoticed in the early to mid-20th century. We recommend that such biases should be considered, or better corrected for, when attributing the frequency of reported GLOFs to atmospheric warming.
KW  - glaciers
KW  - climate change
KW  - hazard
KW  - mountains
KW  - cryosphere
KW  - frequency
Y1  - 2022
U6  - https://doi.org/10.1029/2021EF002426
SN  - 2328-4277
VL  - 10
IS  - 3
PB  - American Geophysical Union
CY  - Washington
ER  - 
TY  - JOUR
A1  - Bryant, Seth
A1  - Davies, Evan
A1  - Sol, David
A1  - Davis, Sandy
T1  - The progression of flood risk in southern Alberta since the 2013 flood
JF  - Journal of flood risk management
N2  - After a century of semi-restricted floodplain development, Southern Alberta, Canada, was struck by the devastating 2013 Flood. Aging infrastructure and limited property-level floodproofing likely contributed to the $4-6 billion (CAD) losses. Following this catastrophe, Alberta has seen a revival in flood management, largely focused on structural protections. However, concurrent with the recent structural work was a 100,000+ increase in Calgary's population in the 5 years following the flood, leading to further densification of high-hazard areas. This study implements the novel Stochastic Object-based Flood damage Dynamic Assessment (SOFDA) model framework to quantify the progression of the direct-damage flood risk in a mature urban neighborhood after the 2013 Flood. Five years of remote-sensing data, property assessment records, and inundation simulations following the flood are used to construct the model. Results show that in these 5 years, vulnerability trends (like densification) have increased flood risk by 4%; however, recent structural mitigation projects have reduced overall flood risk by 47% for this case study. These results demonstrate that the flood management revival in Southern Alberta has largely been successful at reducing flood risk; however, the gains are under threat from continued development and densification absent additional floodproofing regulations.
KW  - Calgary
KW  - depth-damage functions
KW  - expected annual damages
KW  - flood risk
KW  - model
KW  - property level protection measures
KW  - risk analysis
KW  - risk dynamics
Y1  - 2022
U6  - https://doi.org/10.1111/jfr3.12811
SN  - 1753-318X
VL  - 15
IS  - 3
PB  - Wiley-Blackwell
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Dietze, Michael
A1  - Bell, Rainer
A1  - Öztürk, Ugur
A1  - Cook, Kristen L.
A1  - Andermann, Christoff
A1  - Beer, Alexander R.
A1  - Damm, Bodo
A1  - Lucia, Ana
A1  - Fauer, Felix S.
A1  - Nissen, Katrin M.
A1  - Sieg, Tobias
A1  - Thieken, Annegret H.
T1  - More than heavy rain turning into fast-flowing water - a landscape perspective on the 2021 Eifel floods
JF  - Natural hazards and earth system sciences
N2  - Rapidly evolving floods are rare but powerful drivers of landscape reorganisation that have severe and long-lasting impacts on both the functions of a landscape's subsystems and the affected society. The July 2021 flood that particularly hit several river catchments of the Eifel region in western Germany and Belgium was a drastic example. While media and scientists highlighted the meteorological and hydrological aspects of this flood, it was not just the rising water levels in the main valleys that posed a hazard, caused damage, and drove environmental reorganisation. Instead, the concurrent coupling of landscape elements and the wood, sediment, and debris carried by the fast-flowing water made this flood so devastating and difficult to predict. Because more intense floods are able to interact with more landscape components, they at times reveal rare non-linear feedbacks, which may be hidden during smaller events due to their high thresholds of initiation. Here, we briefly review the boundary conditions of the 14-15 July 2021 flood and discuss the emerging features that made this event different from previous floods. We identify hillslope processes, aspects of debris mobilisation, the legacy of sustained human land use, and emerging process connections and feedbacks as critical non-hydrological dimensions of the flood. With this landscape scale perspective, we develop requirements for improved future event anticipation, mitigation, and fundamental system understanding.
Y1  - 2022
U6  - https://doi.org/10.5194/nhess-22-1845-2022
SN  - 1561-8633
SN  - 1684-9981
VL  - 22
IS  - 6
SP  - 1845
EP  - 1856
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Miesner, Timon
A1  - Herzschuh, Ulrike
A1  - Pestryakova, Luidmila Agafyevna
A1  - Wieczorek, Mareike
A1  - Zakharov, Evgenii S.
A1  - Kolmogorov, Alexei I.
A1  - Davydova, Paraskovya V.
A1  - Kruse, Stefan
T1  - Forest structure and individual tree inventories of northeastern Siberia along climatic gradients
JF  - Earth system science data : ESSD
N2  - We compile a data set of forest surveys from expeditions to the northeast of the Russian Federation, in Krasnoyarsk Krai, the Republic of Sakha (Yakutia), and the Chukotka Autonomous Okrug (59-73 degrees N, 97-169 degrees E), performed between the years 2011 and 2021. The region is characterized by permafrost soils and forests dominated by larch (Larix gmelinii Rupr. and Larix cajanderi Mayr). 
Our data set consists of a plot database describing 226 georeferenced vegetation survey plots and a tree database with information about all the trees on these plots. The tree database, consisting of two tables with the same column names, contains information on the height, species, and vitality of 40 289 trees. A subset of the trees was subject to a more detailed inventory, which recorded the stem diameter at base and at breast height, crown diameter, and height of the beginning of the crown.
We recorded heights up to 28.5 m (median 2.5 m) and stand densities up to 120 000 trees per hectare (median 1197 ha(-1)), with both values tending to be higher in the more southerly areas. Observed taxa include Larix Mill., Pinus L., Picea A. Dietr., Abies Mill., Salix L., Betula L., Populus L., Alnus Mill., and Ulmus L. 
In this study, we present the forest inventory data aggregated per plot. Additionally, we connect the data with different remote sensing data products to find out how accurately forest structure can be predicted from such products. Allometries were calculated to obtain the diameter from height measurements for every species group. For Larix, the most frequent of 10 species groups, allometries depended also on the stand density, as denser stands are characterized by thinner trees, relative to height. The remote sensing products used to compare against the inventory data include climate, forest biomass, canopy height, and forest loss or disturbance. We find that the forest metrics measured in the field can only be reconstructed from the remote sensing data to a limited extent, as they depend on local properties. This illustrates the need for ground inventories like those data we present here.
The data can be used for studying the forest structure of northeastern Siberia and for the calibration and validation of remotely sensed data.
Y1  - 2022
U6  - https://doi.org/10.5194/essd-14-5695-2022
SN  - 1866-3508
SN  - 1866-3516
VL  - 14
IS  - 12
SP  - 5695
EP  - 5716
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Kruse, Stefan
A1  - Stünzi, Simone Maria
A1  - Boike, Julia
A1  - Langer, Moritz
A1  - Gloy, Josias
A1  - Herzschuh, Ulrike
T1  - Novel coupled permafrost-forest model (LAVESI-CryoGrid v1.0) revealing the interplay between permafrost, vegetation, and climate across eastern Siberia
JF  - Geoscientific model development : GMD ; an interactive open access journal of the European Geosciences Union
N2  - Boreal forests of Siberia play a relevant role in the global carbon cycle. However, global warming threatens the existence of summergreen larch-dominated ecosystems, likely enabling a transition to evergreen tree taxa with deeper active layers. Complex permafrost-vegetation interactions make it uncertain whether these ecosystems could develop into a carbon source rather than continuing atmospheric carbon sequestration under global warming. Consequently, shedding light on the role of current and future active layer dynamics and the feedbacks with the apparent tree species is crucial to predict boreal forest transition dynamics and thus for aboveground forest biomass and carbon stock developments. Hence, we established a coupled model version amalgamating a one-dimensional permafrost multilayer forest land-surface model (CryoGrid) with LAVESI, an individual-based and spatially explicit forest model for larch species (Larix Mill.), extended for this study by including other relevant Siberian forest species and explicit terrain. <br /> Following parameterization, we ran simulations with the coupled version to the near future to 2030 with a mild climate-warming scenario. We focus on three regions covering a gradient of summergreen forests in the east at Spasskaya Pad, mixed summergreen-evergreen forests close to Nyurba, and the warmest area at Lake Khamra in the southeast of Yakutia, Russia. Coupled simulations were run with the newly implemented boreal forest species and compared to runs allowing only one species at a time, as well as to simulations using just LAVESI. Results reveal that the coupled version corrects for overestimation of active layer thickness (ALT) and soil moisture, and large differences in established forests are simulated. We conclude that the coupled version can simulate the complex environment of eastern Siberia by reproducing vegetation patterns, making it an excellent tool to disentangle processes driving boreal forest dynamics.
Y1  - 2022
U6  - https://doi.org/10.5194/gmd-15-2395-2022
SN  - 1991-959X
SN  - 1991-9603
VL  - 15
IS  - 6
SP  - 2395
EP  - 2422
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Radosavljevic, Boris
A1  - Lantuit, Hugues
A1  - Knoblauch, Christian
A1  - Couture, Nicole
A1  - Herzschuh, Ulrike
A1  - Fritz, Michael
T1  - Arctic nearshore sediment dynamics - an example from Herschel Island - Qikiqtaruk, Canada
JF  - Journal of marine science and engineering
N2  - Increasing arctic coastal erosion rates imply a greater release of sediments and organic matter into the coastal zone. With 213 sediment samples taken around Herschel Island-Qikiqtaruk, Canadian Beaufort Sea, we aimed to gain new insights on sediment dynamics and geochemical properties of a shallow arctic nearshore zone. Spatial characteristics of nearshore sediment texture (moderately to poorly sorted silt) are dictated by hydrodynamic processes, but ice-related processes also play a role. We determined organic matter (OM) distribution and inferred the origin and quality of organic carbon by C/N ratios and stable carbon isotopes delta C-13. The carbon content was higher offshore and in sheltered areas (mean: 1.0 wt.%., S.D.: 0.9) and the C/N ratios also showed a similar spatial pattern (mean: 11.1, S.D.: 3.1), while the delta C-13 (mean: -26.4 parts per thousand VPDB, S.D.: 0.4) distribution was more complex. We compared the geochemical parameters of our study with terrestrial and marine samples from other studies using a bootstrap approach. Sediments of the current study contained 6.5 times and 1.8 times less total organic carbon than undisturbed and disturbed terrestrial sediments, respectively. Therefore, degradation of OM and separation of carbon pools take place on land and continue in the nearshore zone, where OM is leached, mineralized, or transported beyond the study area.
KW  - permafrost
KW  - Arctic Ocean
KW  - stable carbon isotopes
KW  - nitrogen
KW  - sediment
KW  - chemistry
KW  - sediment dynamics
KW  - Beaufort Sea
KW  - grain size
Y1  - 2022
U6  - https://doi.org/10.3390/jmse10111589
SN  - 2077-1312
VL  - 10
IS  - 11
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Dallmeyer, Anne
A1  - Kleinen, Thomas
A1  - Claussen, Martin
A1  - Weitzel, Nils
A1  - Cao, Xianyong
A1  - Herzschuh, Ulrike
T1  - The deglacial forest conundrum
JF  - Nature Communications
N2  - How fast the Northern Hemisphere (NH) forest biome tracks strongly warming climates is largely unknown. Regional studies reveal lags between decades and millennia. Here we report a conundrum: Deglacial forest expansion in the NH extra-tropics occurs approximately 4000 years earlier in a transient MPI-ESM1.2 simulation than shown by pollen-based biome reconstructions. Shortcomings in the model and the reconstructions could both contribute to this mismatch, leaving the underlying causes unresolved. The simulated vegetation responds within decades to simulated climate changes, which agree with pollen-independent reconstructions. Thus, we can exclude climate biases as main driver for differences. Instead, the mismatch points at a multi-millennial disequilibrium of the NH forest biome to the climate signal. Therefore, the evaluation of time-slice simulations in strongly changing climates with pollen records should be critically reassessed. Our results imply that NH forests may be responding much slower to ongoing climate changes than Earth System Models predict. <br /> Deglacial forest expansion in the Northern Hemisphere poses a conundrum: Model results agree with the climate signal but are several millennia ahead of reconstructed forest dynamics. The underlying causes remain unsolved.
Y1  - 2022
U6  - https://doi.org/10.1038/s41467-022-33646-6
SN  - 2041-1723
VL  - 13
IS  - 1
PB  - Nature Publishing Group UK
CY  - [London]
ER  - 
TY  - JOUR
A1  - Kruse, Stefan
A1  - Herzschuh, Ulrike
T1  - Regional opportunities for tundra conservation in the next 1000 years
JF  - eLife
N2  - The biodiversity of tundra areas in northern high latitudes is threatened by invasion of forests under global warming. However, poorly understood nonlinear responses of the treeline ecotone mean the timing and extent of tundra losses are unclear, but policymakers need such information to optimize conservation efforts. Our individual-based model LAVESI, developed for the Siberian tundra-taiga ecotone, can help improve our understanding. Consequently, we simulated treeline migration trajectories until the end of the millennium, causing a loss of tundra area when advancing north. Our simulations reveal that the treeline follows climate warming with a severe, century-long time lag, which is overcompensated by infilling of stands in the long run even when temperatures cool again. Our simulations reveal that only under ambitious mitigation strategies (relative concentration pathway 2.6) will ~30% of original tundra areas remain in the north but separated into two disjunct refugia.
KW  - Larix gmelinii
KW  - Larix cajanderi
KW  - nonlinear response
KW  - treeline ecotone
KW  - tundra
KW  - Ecology
KW  - Short Report
Y1  - 2022
U6  - https://doi.org/10.7554/eLife.75163
SN  - 2050-084X
VL  - 11
PB  - eLife Sciences Publications
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Li, Chenzhi
A1  - Postl, Alexander K.
A1  - Böhmer, Thomas
A1  - Cao, Xianyong
A1  - Dolman, Andrew M.
A1  - Herzschuh, Ulrike
T1  - Harmonized chronologies of a global late Quaternary pollen dataset (LegacyAge 1.0)
JF  - Earth system science data : ESSD
N2  - We present a chronology framework named LegacyAge 1.0 containing harmonized chronologies for 2831 pollen records (downloaded from the Neotoma Paleoecology Database and the supplementary Asian datasets) together with their age control points and metadata in machine-readable data formats.  
All chronologies use the Bayesian framework implemented in Bacon version 2.5.3. Optimal parameter settings of priors (accumulation.shape, memory.strength, memory.mean, accumulation.rate, and thickness) were identified based on information in the original publication or iteratively after preliminary model inspection. 
The most common control points for the chronologies are radiocarbon dates (86.1 %), calibrated by the latest calibration curves (IntCal20 and SHCal20 for the terrestrial radiocarbon dates in the Northern Hemisphere and Southern Hemisphere and Marine20 for marine materials). 
The original publications were consulted when dealing with outliers and inconsistencies. Several major challenges when setting up the chronologies included the waterline issue (18.8% of records), reservoir effect (4.9 %), and sediment deposition discontinuity (4.4 %). 
Finally, we numerically compare the LegacyAge 1.0 chronologies to those published in the original publications and show that the reliability of the chronologies of 95.4% of records could be improved according to our assessment. 
Our chronology framework and revised chronologies provide the opportunity to make use of the ages and age uncertainties in synthesis studies of, for example, pollen-based vegetation and climate change. 
The LegacyAge 1.0 dataset, including metadata, datings, harmonized chronologies, and R code used, is openaccess and available at PANGAEA (https://doi.org/10.1594/PANGAEA.933132; Li et al., 2021) and Zenodo (https://doi.org/10.5281/zenodo.5815192; Li et al., 2022), respectively.
Y1  - 2022
U6  - https://doi.org/10.5194/essd-14-1331-2022
SN  - 1866-3508
SN  - 1866-3516
VL  - 14
IS  - 3
SP  - 1331
EP  - 1343
PB  - Copernics Publications
CY  - Katlenburg-Lindau
ER  - 
TY  - JOUR
A1  - Schmidt, Lena Katharina
A1  - Francke, Till
A1  - Rottler, Erwin
A1  - Blume, Theresa
A1  - Schöber, Johannes
A1  - Bronstert, Axel
T1  - Suspended sediment and discharge dynamics in a glaciated alpine environment
BT  - identifying crucial areas and time periods on several spatial and temporal scales in the Ötztal, Austria
JF  - Earth surface dynamics
N2  - Glaciated high-alpine areas are fundamentally altered by climate change, with well-known implications for hydrology, e.g., due to glacier retreat, longer snow-free periods, and more frequent and intense summer rainstorms. While knowledge on how these hydrological changes will propagate to suspended sediment dynamics is still scarce, it is needed to inform mitigation and adaptation strategies. To understand the processes and source areas most relevant to sediment dynamics, we analyzed discharge and sediment dynamics in high temporal resolution as well as their patterns on several spatial scales, which to date few studies have done.

We used a nested catchment setup in the Upper Ötztal in Tyrol, Austria, where high-resolution (15 min) time series of discharge and suspended sediment concentrations are available for up to 15 years (2006–2020). The catchments of the gauges in Vent, Sölden and Tumpen range from 100 to almost 800 km2 with 10 % to 30 % glacier cover and span an elevation range of 930 to 3772 m a.s.l. We analyzed discharge and suspended sediment yields (SSY), their distribution in space, their seasonality and spatial differences therein, and the relative importance of short-term events. We complemented our analysis by linking the observations to satellite-based snow cover maps, glacier inventories, mass balances and precipitation data.

Our results indicate that the areas above 2500 m a.s.l., characterized by glacier tongues and the most recently deglaciated areas, are crucial for sediment generation in all sub-catchments. This notion is supported by the synchronous spring onset of sediment export at the three gauges, which coincides with snowmelt above 2500 m but lags behind spring discharge onsets. This points at a limitation of suspended sediment supply as long as the areas above 2500 m are snow-covered. The positive correlation of annual SSY with glacier cover (among catchments) and glacier mass balances (within a catchment) further supports the importance of the glacier-dominated areas. The analysis of short-term events showed that summer precipitation events were associated with peak sediment concentrations and yields but on average accounted for only 21 % of the annual SSY in the headwaters. These results indicate that under current conditions, thermally induced sediment export (through snow and glacier melt) is dominant in the study area.

Our results extend the scientific knowledge on current hydro-sedimentological conditions in glaciated high-alpine areas and provide a baseline for studies on projected future changes in hydro-sedimentological system dynamics.
Y1  - 2022
U6  - https://doi.org/10.5194/esurf-10-653-2022
SN  - 2196-632X
SN  - 2196-6311
VL  - 10
IS  - 3
SP  - 653
EP  - 669
PB  - Copernicus Publications
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Heistermann, Maik
A1  - Bogena, Heye
A1  - Francke, Till
A1  - Güntner, Andreas
A1  - Jakobi, Jannis
A1  - Rasche, Daniel
A1  - Schrön, Martin
A1  - Döpper, Veronika
A1  - Fersch, Benjamin
A1  - Groh, Jannis
A1  - Patil, Amol
A1  - Pütz, Thomas
A1  - Reich, Marvin
A1  - Zacharias, Steffen
A1  - Zengerle, Carmen
A1  - Oswald, Sascha
T1  - Soil moisture observation in a forested headwater catchment: Combining a dense cosmic-ray neutron sensor network with roving and hydrogravimetry at the TERENO site Wüstebach
JF  - Earth system science data
N2  - Cosmic-ray neutron sensing (CRNS) has become an effective method to measure soil moisture at a horizontal scale of hundreds of metres and a depth of decimetres. Recent studies proposed operating CRNS in a network with overlapping footprints in order to cover root-zone water dynamics at the small catchment scale and, at the same time, to represent spatial heterogeneity. In a joint field campaign from September to November 2020 (JFC-2020), five German research institutions deployed 15 CRNS sensors in the 0.4 km(2) Wustebach catchment (Eifel mountains, Germany). The catchment is dominantly forested (but includes a substantial fraction of open vegetation) and features a topographically distinct catchment boundary. In addition to the dense CRNS coverage, the campaign featured a unique combination of additional instruments and techniques: hydro-gravimetry (to detect water storage dynamics also below the root zone); ground-based and, for the first time, airborne CRNS roving; an extensive wireless soil sensor network, supplemented by manual measurements; and six weighable lysimeters. Together with comprehensive data from the long-term local research infrastructure, the published data set (available at https://doi.org/10.23728/b2share.756ca0485800474e9dc7f5949c63b872; Heistermann et al., 2022) will be a valuable asset in various research contexts: to advance the retrieval of landscape water storage from CRNS, wireless soil sensor networks, or hydrogravimetry; to identify scale-specific combinations of sensors and methods to represent soil moisture variability; to improve the understanding and simulation of land-atmosphere exchange as well as hydrological and hydrogeological processes at the hillslope and the catchment scale; and to support the retrieval of soil water content from airborne and spaceborne remote sensing platforms.
Y1  - 2022
U6  - https://doi.org/10.5194/essd-14-2501-2022
SN  - 1866-3508
SN  - 1866-3516
VL  - 14
IS  - 5
SP  - 2501
EP  - 2519
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Walch, Daniela M. R.
A1  - Singh, Rakesh K.
A1  - Soreide, Janne E.
A1  - Lantuit, Hugues
A1  - Poste, Amanda
T1  - Spatio-temporal variability of suspended particulate matter in a high-arctic estuary (Adventfjorden, Svalbard) using sentinel-2 time-series
JF  - Remote sensing
N2  - Arctic coasts, which feature land-ocean transport of freshwater, sediments, and other terrestrial material, are impacted by climate change, including increased temperatures, melting glaciers, changes in precipitation and runoff. 
These trends are assumed to affect productivity in fjordic estuaries. 
However, the spatial extent and temporal variation of the freshwater-driven darkening of fjords remain unresolved. 

The present study illustrates the spatio-temporal variability of suspended particulate matter (SPM) in the Adventfjorden estuary, Svalbard, using in-situ field campaigns and ocean colour remote sensing (OCRS) via high-resolution Sentinel-2 imagery. 
To compute SPM concentration (C-SPMsat), a semi-analytical algorithm was regionally calibrated using local in-situ data, which improved the accuracy of satellite-derived SPM concentration by similar to 20% (MRD). Analysis of SPM concentration for two consecutive years (2019, 2020) revealed strong seasonality of SPM in Adventfjorden. 
Highest estimated SPM concentrations and river plume extent (% of fjord with C-SPMsat > 30 mg L-1) occurred during June, July, and August. 

Concurrently, we observed a strong relationship between river plume extent and average air temperature over the 24 h prior to the observation (R-2 = 0.69). 
Considering predicted changes to environmental conditions in the Arctic region, this study highlights the importance of the rapidly changing environmental parameters and the significance of remote sensing in analysing fluxes in light attenuating particles, especially in the coastal Arctic Ocean.
KW  - ocean colour
KW  - coastal darkening
KW  - SPM
KW  - sediment plumes
KW  - Arctic coast
KW  - remote sensing
KW  - regional tuning
KW  - coastal ecosystems;
KW  - land-ocean-interaction
KW  - riverine inputs
Y1  - 2022
U6  - https://doi.org/10.3390/rs14133123
SN  - 2072-4292
VL  - 14
IS  - 13
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Veh, Georg
A1  - Lützow, Natalie
A1  - Kharlamova, Varvara
A1  - Petrakov, Dmitry
A1  - Hugonnet, Romain
A1  - Korup, Oliver
T1  - Trends, Breaks, and Biases in the Frequency of Reported Glacier Lake Outburst Floods
JF  - Earth's Future
N2  - Thousands of glacier lakes have been forming behind natural dams in high mountains following glacier retreat since the early 20th century. Some of these lakes abruptly released pulses of water and sediment with disastrous downstream consequences. Yet it remains unclear whether the reported rise of these glacier lake outburst floods (GLOFs) has been fueled by a warming atmosphere and enhanced meltwater production, or simply a growing research effort. Here we estimate trends and biases in GLOF reporting based on the largest global catalog of 1,997 dated glacier-related floods in six major mountain ranges from 1901 to 2017. We find that the positive trend in the number of reported GLOFs has decayed distinctly after a break in the 1970s, coinciding with independently detected trend changes in annual air temperatures and in the annual number of field-based glacier surveys (a proxy of scientific reporting). We observe that GLOF reports and glacier surveys decelerated, while temperature rise accelerated in the past five decades. Enhanced warming alone can thus hardly explain the annual number of reported GLOFs, suggesting that temperature-driven glacier lake formation, growth, and failure are weakly coupled, or that outbursts have been overlooked. Indeed, our analysis emphasizes a distinct geographic and temporal bias in GLOF reporting, and we project that between two to four out of five GLOFs on average might have gone unnoticed in the early to mid-20th century. We recommend that such biases should be considered, or better corrected for, when attributing the frequency of reported GLOFs to atmospheric warming.
Y1  - 2022
U6  - https://doi.org/10.1029/2021EF002426
SN  - 2328-4277
VL  - 10
SP  - 1
EP  - 14
PB  - Wiley-Blackwell
CY  - Hoboken, New Jersey
ET  - 3
ER  - 
TY  - JOUR
A1  - Heistermann, Maik
A1  - Bogena, Heye
A1  - Francke, Till
A1  - Güntner, Andreas
A1  - Jakobi, Jannis
A1  - Rasche, Daniel
A1  - Schrön, Martin
A1  - Döpper, Veronika
A1  - Fersch, Benjamin
A1  - Groh, Jannis
A1  - Patil, Amol
A1  - Pütz, Thomas
A1  - Reich, Marvin
A1  - Zacharias, Steffen
A1  - Zengerle, Carmen
A1  - Oswald, Sascha
T1  - Soil moisture observation in a forested headwater catchment: combining a dense cosmic-ray neutron sensor network with roving and hydrogravimetry at the TERENO site Wüstebach
JF  - Earth system science data : ESSD
N2  - Cosmic-ray neutron sensing (CRNS) has become an effective method to measure soil moisture at a horizontal scale of hundreds of metres and a depth of decimetres. Recent studies proposed operating CRNS in a network with overlapping footprints in order to cover root-zone water dynamics at the small catchment scale and, at the same time, to represent spatial heterogeneity. In a joint field campaign from September to November 2020 (JFC-2020), five German research institutions deployed 15 CRNS sensors in the 0.4 km2 Wüstebach catchment (Eifel mountains, Germany). The catchment is dominantly forested (but includes a substantial fraction of open vegetation) and features a topographically distinct catchment boundary. In addition to the dense CRNS coverage, the campaign featured a unique combination of additional instruments and techniques: hydro-gravimetry (to detect water storage dynamics also below the root zone); ground-based and, for the first time, airborne CRNS roving; an extensive wireless soil sensor network, supplemented by manual measurements; and six weighable lysimeters. Together with comprehensive data from the long-term local research infrastructure, the published data set (available at https://doi.org/10.23728/b2share.756ca0485800474e9dc7f5949c63b872; Heistermann et al., 2022) will be a valuable asset in various research contexts: to advance the retrieval of landscape water storage from CRNS, wireless soil sensor networks, or hydrogravimetry; to identify scale-specific combinations of sensors and methods to represent soil moisture variability; to improve the understanding and simulation of land–atmosphere exchange as well as hydrological and hydrogeological processes at the hillslope and the catchment scale; and to support the retrieval of soil water content from airborne and spaceborne remote sensing platforms.
Y1  - 2022
U6  - https://doi.org/10.5194/essd-14-2501-2022
SN  - 1866-3516
SN  - 1866-3508
VL  - 14
IS  - 5
SP  - 2501
EP  - 2519
PB  - Copernicus
CY  - Katlenburg-Lindau
ER  - 
TY  - JOUR
A1  - Seleem, Omar
A1  - Ayzel, Georgy
A1  - Bronstert, Axel
A1  - Heistermann, Maik
T1  - Transferability of data-driven models to predict urban pluvial flood water depth in Berlin, Germany
JF  - Natural Hazards and Earth System Sciences
N2  - Data-driven models have been recently suggested to surrogate computationally expensive hydrodynamic models to map flood hazards. However, most studies focused on developing models for the same area or the same precipitation event. It is thus not obvious how transferable the models are in space. This study evaluates the performance of a convolutional neural network (CNN) based on the U-Net architecture and the random forest (RF) algorithm to predict flood water depth, the models' transferability in space and performance improvement using transfer learning techniques. We used three study areas in Berlin to train, validate and test the models. The results showed that (1) the RF models outperformed the CNN models for predictions within the training domain, presumable at the cost of overfitting; (2) the CNN models had significantly higher potential than the RF models to generalize beyond the training domain; and (3) the CNN models could better benefit from transfer learning technique to boost their performance outside training domains than RF models.
Y1  - 2023
U6  - https://doi.org/10.5194/nhess-23-809-2023
SN  - 1684-9981
SN  - 1561-8633
VL  - 23
IS  - 2
SP  - 809
EP  - 822
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Heistermann, Maik
A1  - Francke, Till
A1  - Scheiffele, Lena
A1  - Petrova, Katya Dimitrova
A1  - Budach, Christian
A1  - Schrön, Martin
A1  - Trost, Benjamin
A1  - Rasche, Daniel
A1  - Güntner, Andreas
A1  - Doepper, Veronika
A1  - Förster, Michael
A1  - Köhli, Markus
A1  - Angermann, Lisa
A1  - Antonoglou, Nikolaos
A1  - Zude, Manuela
A1  - Oswald, Sascha
T1  - Three years of soil moisture observations by a dense cosmic-ray neutron sensing cluster at an agricultural research site in north-east Germany
JF  - Earth system science data : ESSD
N2  - Cosmic-ray neutron sensing (CRNS) allows for the estimation of root-zone soil water content (SWC) at the scale of several hectares. In this paper, we present the data recorded by a dense CRNS network operated from 2019 to 2022 at an agricultural research site in Marquardt, Germany - the first multi-year CRNS cluster. Consisting, at its core, of eight permanently installed CRNS sensors, the cluster was supplemented by a wealth of complementary measurements: data from seven additional temporary CRNS sensors, partly co-located with the permanent ones; 27 SWC profiles (mostly permanent); two groundwater observation wells; meteorological records; and Global Navigation Satellite System reflectometry (GNSS-R). Complementary to these continuous measurements, numerous campaign-based activities provided data by mobile CRNS roving, hyperspectral im-agery via UASs, intensive manual sampling of soil properties (SWC, bulk density, organic matter, texture, soil hydraulic properties), and observations of biomass and snow (cover, depth, and density). The unique temporal coverage of 3 years entails a broad spectrum of hydro-meteorological conditions, including exceptional drought periods and extreme rainfall but also episodes of snow coverage, as well as a dedicated irrigation experiment. Apart from serving to advance CRNS-related retrieval methods, this data set is expected to be useful for vari-ous disciplines, for example, soil and groundwater hydrology, agriculture, or remote sensing. Hence, we show exemplary features of the data set in order to highlight the potential for such subsequent studies. The data are available at doi.org/10.23728/b2share.551095325d74431881185fba1eb09c95 (Heistermann et al., 2022b).
Y1  - 2023
U6  - https://doi.org/10.5194/essd-15-3243-2023
SN  - 1866-3508
SN  - 1866-3516
VL  - 15
IS  - 7
SP  - 3243
EP  - 3262
PB  - Copernics Publications
CY  - Katlenburg-Lindau
ER  -