TY - JOUR
A1 - Stiegler, Jonas
A1 - Pahl, Janice
A1 - Guillen, Rafael Arce
A1 - Ullmann, Wiebke
A1 - Blaum, Niels
T1 - The heat is on
BT - impacts of rising temperature on the activity of a common European mammal
JF - Frontiers in Ecology and Evolution
N2 - Climate conditions severely impact the activity and, consequently, the fitness of wildlife species across the globe. Wildlife can respond to new climatic conditions, but the pace of human-induced change limits opportunities for adaptation or migration. Thus, how these changes affect behavior, movement patterns, and activity levels remains unclear. In this study, we investigate how extreme weather conditions affect the activity of European hares (Lepus europaeus) during their peak reproduction period. When hares must additionally invest energy in mating, prevailing against competitors, or lactating, we investigated their sensitivities to rising temperatures, wind speed, and humidity. To quantify their activity, we used the overall dynamic body acceleration (ODBA) calculated from tri-axial acceleration measurements of 33 GPS-collared hares. Our analysis revealed that temperature, humidity, and wind speed are important in explaining changes in activity, with a strong response for high temperatures above 25 & DEG;C and the highest change in activity during temperature extremes of over 35 & DEG;C during their inactive period. Further, we found a non-linear relationship between temperature and activity and an interaction of activity changes between day and night. Activity increased at higher temperatures during the inactive period (day) and decreased during the active period (night). This decrease was strongest during hot tropical nights. At a stage of life when mammals such as hares must substantially invest in reproduction, the sensitivity of females to extreme temperatures was particularly pronounced. Similarly, both sexes increased their activity at high humidity levels during the day and low wind speeds, irrespective of the time of day, while the effect of humidity was stronger for males. Our findings highlight the importance of understanding the complex relationships between extreme weather conditions and mammal behavior, critical for conservation and management. With ongoing climate change, extreme weather events such as heat waves and heavy rainfall are predicted to occur more often and last longer. These events will directly impact the fitness of hares and other wildlife species and hence the population dynamics of already declining populations across Europe.
KW - activity
KW - ODBA
KW - animal tracking
KW - European hare
KW - extreme weather events
KW - climate change
Y1 - 2023
U6 - https://doi.org/10.3389/fevo.2023.1193861
SN - 2296-701X
VL - 11
PB - Frontiers Media
CY - Lausanne
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 - Souto-Veiga, Rodrigo
A1 - Groeneveld, Juergen
A1 - Enright, Neal J.
A1 - Fontaine, Joseph B.
A1 - Jeltsch, Florian
T1 - Declining pollination success reinforces negative climate and fire change impacts in a serotinous, fire-killed plant
JF - Plant ecology : an international journal
N2 - Climate change projections predict that Mediterranean-type ecosystems (MTEs) are becoming hotter and drier and that fires will become more frequent and severe.
While most plant species in these important biodiversity hotspots are adapted to hot, dry summers and recurrent fire, the Interval Squeeze framework suggests that reduced seed production (demographic shift), reduced seedling establishment after fire (post fire recruitment shift), and reduction in the time between successive fires (fire interval shift) will threaten fire killed species under climate change.
One additional potential driver of accelerated species decline, however, has not been considered so far: the decrease in pollination success observed in many ecosystems worldwide has the potential to further reduce seed accumulation and thus population persistence also in these already threatened systems.
Using the well-studied fire-killed and serotinous shrub species Banksia hookeriana as an example, we apply a new spatially implicit population simulation model to explore population dynamics under past (1988-2002) and current (2003-2017) climate conditions, deterministic and stochastic fire regimes, and alternative scenarios of pollination decline.
Overall, model results suggest that while B. hookeriana populations were stable under past climate conditions, they will not continue to persist under current (and prospective future) climate.
Negative effects of climatic changes and more frequent fires are reinforced by the measured decline in seed set leading to further reduction in the mean persistence time by 12-17%.
These findings clearly indicate that declining pollination rates can be a critical factor that increases further the pressure on the persistence of fire-killed plants.
Future research needs to investigate whether other fire-killed species are similarly threatened, and if local population extinction may be compensated by recolonization events, facilitating persistence in spatially structured meta-communities.
KW - climate change
KW - fire frequency
KW - interval squeeze
KW - pollination
KW - process-based simulation model
KW - mediterranean-type ecosystem
Y1 - 2022
U6 - https://doi.org/10.1007/s11258-022-01244-7
SN - 1385-0237
SN - 1573-5052
VL - 223
IS - 7
SP - 863
EP - 881
PB - Springer
CY - Dordrecht
ER -
TY - JOUR
A1 - Ben Nsir, Siwar
A1 - Jomaa, Seifeddine
A1 - Yildirim, Umit
A1 - Zhou, Xiangqian
A1 - D'Oria, Marco
A1 - Rode, Michael
A1 - Khlifi, Slaheddine
T1 - Assessment of climate change impact on discharge of the lakhmass catchment (Northwest Tunisia)
JF - Water
N2 - The Mediterranean region is increasingly recognized as a climate change hotspot but is highly underrepresented in hydrological climate change studies. This study aims to investigate the climate change effects on the hydrology of Lakhmass catchment in Tunisia. Lakhmass catchment is a part of the Medium Valley of Medjerda in northwestern Tunisia that drains an area of 126 km(2). First, the Hydrologiska Byrans Vattenbalansavdelning light (HBV-light) model was calibrated and validated successfully at a daily time step to simulate discharge during the 1981-1986 period. The Nash Sutcliffe Efficiency and Percent bias (NSE, PBIAS) were (0.80, +2.0%) and (0.53, -9.5%) for calibration (September 1982-August 1984) and validation (September 1984-August 1986) periods, respectively. Second, HBV-light model was considered as a predictive tool to simulate discharge in a baseline period (1981-2009) and future projections using data (precipitation and temperature) from thirteen combinations of General Circulation Models (GCMs) and Regional Climatic Models (RCMs). We used two trajectories of Representative Concentration Pathways, RCP4.5 and RCP8.5, suggested by the Intergovernmental Panel on Climate Change (IPCC). Each RCP is divided into three projection periods: near-term (2010-2039), mid-term (2040-2069) and long-term (2070-2099). For both scenarios, a decrease in precipitation and discharge will be expected with an increase in air temperature and a reduction in precipitation with almost 5% for every +1 degrees C of global warming. By long-term (2070-2099) projection period, results suggested an increase in temperature with about 2.7 degrees C and 4 degrees C, and a decrease in precipitation of approximately 7.5% and 15% under RCP4.5 and RCP8.5, respectively. This will likely result in a reduction of discharge of 12.5% and 36.6% under RCP4.5 and RCP8.5, respectively. This situation calls for early climate change adaptation measures under a participatory approach, including multiple stakeholders and water users.
KW - hydrological modeling
KW - HBV-light model
KW - Mediterranean
KW - discharge
KW - climate change
KW - RCP4,5 and 8,5
Y1 - 2022
U6 - https://doi.org/10.3390/w14142242
SN - 2073-4441
VL - 14
IS - 14
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - McCool, Weston C.
A1 - Codding, Brian F.
A1 - Vernon, Kenneth B.
A1 - Wilson, Kurt M.
A1 - Yaworsky, Peter M.
A1 - Marwan, Norbert
A1 - Kennett, Douglas J.
T1 - Climate change-induced population pressure drives high rates of lethal violence in the Prehispanic central Andes
JF - Proceedings of the National Academy of Sciences of the United States of America : PNAS
N2 - Understanding the influence of climate change and population pressure on human conflict remains a critically important topic in the social sciences. Long-term records that evaluate these dynamics across multiple centuries and outside the range of modern climatic variation are especially capable of elucidating the relative effect of-and the interaction between-climate and demography. This is crucial given that climate change may structure population growth and carrying capacity, while both climate and population influence per capita resource availability. This study couples paleoclimatic and demographic data with osteological evaluations of lethal trauma from 149 directly accelerator mass spectrometry C-14-dated individuals from the Nasca highland region of Peru. Multiple local and supraregional precipitation proxies are combined with a summed probability distribution of 149 C-14 dates to estimate population dynamics during a 700-y study window. Counter to previous findings, our analysis reveals a precipitous increase in violent deaths associated with a period of productive and stable climate, but volatile population dynamics. We conclude that favorable local climate conditions fostered population growth that put pressure on the marginal and highly circumscribed resource base, resulting in violent resource competition that manifested in over 450 y of internecine warfare. These findings help support a general theory of intergroup violence, indicating that relative resource scarcity-whether driven by reduced resource abundance or increased competition-can lead to violence in subsistence societies when the outcome is lower per capita resource availability.
KW - climate change
KW - population pressure
KW - warfare
KW - lethal violence
KW - Andes
Y1 - 2022
U6 - https://doi.org/10.1073/pnas.2117556119
SN - 0027-8424
SN - 1091-6490
VL - 119
IS - 17
PB - National Acad. of Sciences
CY - Washington
ER -
TY - JOUR
A1 - Kong, Xiangzhen
A1 - Ghaffar, Salman
A1 - Determann, Maria
A1 - Friese, Kurt
A1 - Jomaa, Seifeddine
A1 - Mi, Chenxi
A1 - Shatwell, Tom
A1 - Rinke, Karsten
A1 - Rode, Michael
T1 - Reservoir water quality deterioration due to deforestation emphasizes the indirect effects of global change
JF - Water research : a journal of the International Association on Water Quality (IAWQ)
N2 - Deforestation is currently a widespread phenomenon and a growing environmental concern in the era of rapid climate change.
In temperate regions, it is challenging to quantify the impacts of deforestation on the catchment dynamics and downstream aquatic ecosystems such as reservoirs and disentangle these from direct climate change impacts, let alone project future changes to inform management.
Here, we tackled this issue by investigating a unique catchment-reservoir system with two reservoirs in distinct trophic states (meso- and eutrophic), both of which drain into the largest drinking water reservoir in Germany.
Due to the prolonged droughts in 2015-2018, the catchment of the mesotrophic reservoir lost an unprecedented area of forest (exponential increase since 2015 and ca. 17.1% loss in 2020 alone).
We coupled catchment nutrient exports (HYPE) and reservoir ecosystem dynamics (GOTM-WET) models using a process-based modeling approach. The coupled model was validated with datasets spanning periods of rapid deforestation, which makes our future projections highly robust.
Results show that in a short-term time scale (by 2035), increasing nutrient flux from the catchment due to vast deforestation (80% loss) can turn the mesotrophic reservoir into a eutrophic state as its counterpart.
Our results emphasize the more prominent impacts of deforestation than the direct impact of climate warming in impairment of water quality and ecological services to downstream aquatic ecosystems. Therefore, we propose to evaluate the impact of climate change on temperate reservoirs by incorporating a time scale-dependent context, highlighting the indirect impact of deforestation in the short-term scale. In the long-term scale (e.g. to 2100), a guiding hypothesis for future research may be that indirect effects (e.g., as mediated by catchment dynamics) are as important as the direct effects of climate warming on aquatic ecosystems.
KW - deforestation
KW - climate change
KW - temperate regions
KW - reservoir
KW - eutrophication
KW - process-based modeling
Y1 - 2022
U6 - https://doi.org/10.1016/j.watres.2022.118721
SN - 0043-1354
SN - 1879-2448
VL - 221
PB - Elsevier Science
CY - Amsterdam [u.a.]
ER -
TY - JOUR
A1 - Katzenberger, Anja
A1 - Levermann, Anders
A1 - Schewe, Jacob
A1 - Pongratz, Julia
T1 - Intensification of very wet monsoon seasons in India under global warming
JF - Geophysical research letters
N2 - Rainfall-intense summer monsoon seasons on the Indian subcontinent that are exceeding long-term averages cause widespread floods and landslides.
Here we show that the latest generation of coupled climate models robustly project an intensification of very rainfall-intense seasons (June-September).
Under the shared socioeconomic pathway SSP5-8.5, very wet monsoon seasons as observed in only 5 years in the period 1965-2015 are projected to occur 8 times more often in 2050-2100 in the multi-model average.
Under SSP2-4.5, these seasons become only a factor of 6 times more frequent, showing that even modest efforts to mitigate climate change can have a strong impact on the frequency of very strong rainfall seasons.
Besides, we find that the increasing risk of extreme seasonal rainfall is accompanied by a shift from days with light rainfall to days with moderate or heavy rainfall. Additionally, the number of wet days is projected to increase.
KW - Indian monsoon
KW - climate modeling
KW - extreme seasons
KW - climate change
KW - CMIP6
KW - India
Y1 - 2022
U6 - https://doi.org/10.1029/2022GL098856
SN - 0094-8276
SN - 1944-8007
VL - 49
IS - 15
PB - American Geophysical Union
CY - Washington
ER -
TY - JOUR
A1 - Kuhla, Kilian
A1 - Willner, Sven N.
A1 - Otto, Christian
A1 - Geiger, Tobias
A1 - Levermann, Anders
T1 - Ripple resonance amplifies economic welfare loss from weather extremes
JF - Environmental research letters : ERL / Institute of Physics
N2 - The most complex but potentially most severe impacts of climate change are caused by extreme weather events. In a globally connected economy, damages can cause remote perturbations and cascading consequences-a ripple effect along supply chains. Here we show an economic ripple resonance that amplifies losses when consecutive or overlapping weather extremes and their repercussions interact. This amounts to an average amplification of 21% for climate-induced heat stress, river floods, and tropical cyclones. Modeling the temporal evolution of 1.8 million trade relations between >7000 regional economic sectors, we find that the regional responses to future extremes are strongly heterogeneous also in their resonance behavior. The induced effect on welfare varies between gains due to increased demand in some regions and losses due to demand or supply shortages in others. Within the current global supply network, the ripple resonance effect of extreme weather is strongest in high-income economies-an important effect to consider when evaluating past and future economic climate impacts.
KW - consecutive disasters
KW - economic ripple resonance
KW - repercussion resonance
KW - weather extremes
KW - supply network
KW - climate impacts
KW - climate change
Y1 - 2021
U6 - https://doi.org/10.1088/1748-9326/ac2932
SN - 1748-9326
VL - 16
IS - 11
PB - IOP Publ. Ltd.
CY - Bristol
ER -
TY - JOUR
A1 - Pearce, Warren
A1 - Özkula, Suay M.
A1 - Greene, Amanda K.
A1 - Teeling, Lauren
A1 - Bansard, Jennifer S.
A1 - Omena, Janna Joceli
A1 - Rabello, Elaine Teixeira
T1 - Visual cross-platform analysis
JF - Information, Communication and Society: digital methods to research social media images
N2 - Analysis of social media using digital methods is a flourishing approach. However, the relatively easy availability of data collected via platform application programming interfaces has arguably led to the predominance of single-platform research of social media. Such research has also privileged the role of text in social media analysis, as a form of data that is more readily gathered and searchable than images. In this paper, we challenge both of these prevailing forms of social media research by outlining a methodology for visual cross-platform analysis (VCPA), defined as the study of still and moving images across two or more social media platforms. Our argument contains three steps. First, we argue that cross-platform analysis addresses a gap in research methods in that it acknowledges the interplay between a social phenomenon under investigation and the medium within which it is being researched, thus illuminating the different affordances and cultures of web platforms. Second, we build on the literature on multimodal communication and platform vernacular to provide a rationale for incorporating the visual into cross-platform analysis. Third, we reflect on an experimental cross-platform analysis of images within social media posts (n = 471,033) used to communicate climate change to advance different modes of macro- and meso-levels of analysis that are natively visual: image-text networks, image plots and composite images. We conclude by assessing the research pathways opened up by VCPA, delineating potential contributions to empirical research and theory and the potential impact on practitioners of social media communication.
KW - research methodology
KW - visual analysis
KW - social media
KW - climate change
Y1 - 2018
U6 - https://doi.org/10.1080/1369118X.2018.1486871
SN - 1468-4462
SN - 1369-118X
VL - 23
IS - 2
SP - 161
EP - 180
PB - Routledge
CY - London
ER -
TY - JOUR
A1 - Palmer, Matthew D.
A1 - Gregory, Jonathan
A1 - Bagge, Meike
A1 - Calvert, Daley
A1 - Hagedoorn, Jan Marius
A1 - Howard, Tom
A1 - Klemann, Volker
A1 - Lowe, Jason A.
A1 - Roberts, Chris
A1 - Slangen, Aimee B. A.
A1 - Spada, Giorgio
T1 - Exploring the drivers of global and local sea‐level change over the 21st century and beyond
JF - Earth's future
N2 - We present a new set of global and local sea‐level projections at example tide gauge locations under the RCP2.6, RCP4.5, and RCP8.5 emissions scenarios. Compared to the CMIP5‐based sea‐level projections presented in IPCC AR5, we introduce a number of methodological innovations, including (i) more comprehensive treatment of uncertainties, (ii) direct traceability between global and local projections, and (iii) exploratory extended projections to 2300 based on emulation of individual CMIP5 models. Combining the projections with observed tide gauge records, we explore the contribution to total variance that arises from sea‐level variability, different emissions scenarios, and model uncertainty. For the period out to 2300 we further breakdown the model uncertainty by sea‐level component and consider the dependence on geographic location, time horizon, and emissions scenario. Our analysis highlights the importance of local variability for sea‐level change in the coming decades and the potential value of annual‐to‐decadal predictions of local sea‐level change. Projections to 2300 show a substantial degree of committed sea‐level rise under all emissions scenarios considered and highlight the reduced future risk associated with RCP2.6 and RCP4.5 compared to RCP8.5. Tide gauge locations can show large ( > 50%) departures from the global average, in some cases even reversing the sign of the change. While uncertainty in projections of the future Antarctic ice dynamic response tends to dominate post‐2100, we see substantial differences in the breakdown of model variance as a function of location, time scale, and emissions scenario.
KW - climate change
KW - CMIP5 models
KW - RCP scenarios
KW - sea-level projections
KW - tide gauge observations
Y1 - 2020
U6 - https://doi.org/10.1029/2019EF001413
SN - 2328-4277
VL - 8
IS - 9
SP - 1
EP - 25
PB - Wiley-Blackwell
CY - Hoboken
ER -
TY - JOUR
A1 - Leins, Johannes A.
A1 - Grimm, Volker
A1 - Drechsler, Martin
T1 - Large-scale PVA modeling of insects in cultivated grasslands
BT - the role of dispersal in mitigating the effects of management schedules under climate change
JF - Ecology and evolution
N2 - In many species, dispersal is decisive for survival in a changing climate. Simulation models for population dynamics under climate change thus need to account for this factor. Moreover, large numbers of species inhabiting agricultural landscapes are subject to disturbances induced by human land use. We included dispersal in the HiLEG model that we previously developed to study the interaction between climate change and agricultural land use in single populations. Here, the model was parameterized for the large marsh grasshopper (LMG) in cultivated grasslands of North Germany to analyze (1) the species development and dispersal success depending on the severity of climate change in subregions, (2) the additional effect of grassland cover on dispersal success, and (3) the role of dispersal in compensating for detrimental grassland mowing. Our model simulated population dynamics in 60-year periods (2020-2079) on a fine temporal (daily) and high spatial (250 x 250 m(2)) scale in 107 subregions, altogether encompassing a range of different grassland cover, climate change projections, and mowing schedules. We show that climate change alone would allow the LMG to thrive and expand, while grassland cover played a minor role. Some mowing schedules that were harmful to the LMG nevertheless allowed the species to moderately expand its range. Especially under minor climate change, in many subregions dispersal allowed for mowing early in the year, which is economically beneficial for farmers. More severe climate change could facilitate LMG expansion to uninhabited regions but would require suitable mowing schedules along the path. These insights can be transferred to other species, given that the LMG is considered a representative of grassland communities. For more specific predictions on the dynamics of other species affected by climate change and land use, the publicly available HiLEG model can be easily adapted to the characteristics of their life cycle.
KW - bilinear interpolation
KW - climate change
KW - dispersal success
KW - land use
KW - large marsh grasshopper
KW - spatially explicit model
Y1 - 2022
U6 - https://doi.org/10.1002/ece3.9063
SN - 2045-7758
VL - 12
IS - 7
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Huber, Veronika
A1 - Krummenauer, Linda
A1 - Peña-Ortiz, Cristina
A1 - Lange, Stefan
A1 - Gasparrini, Antonio
A1 - Vicedo-Cabrera, Ana Maria
A1 - Garcia-Herrera, Ricardo
A1 - Frieler, Katja
T1 - Temperature-related excess mortality in German cities at 2 °C and higher degrees of global warming
JF - Environmental Research
N2 - Background: Investigating future changes in temperature-related mortality as a function of global mean temperature (GMT) rise allows for the evaluation of policy-relevant climate change targets. So far, only few studies have taken this approach, and, in particular, no such assessments exist for Germany, the most populated country of Europe.
Methods: We assess temperature-related mortality in 12 major German cities based on daily time-series of all-cause mortality and daily mean temperatures in the period 1993-2015, using distributed-lag non-linear models in a two-stage design. Resulting risk functions are applied to estimate excess mortality in terms of GMT rise relative to pre-industrial levels, assuming no change in demographics or population vulnerability.
Results: In the observational period, cold contributes stronger to temperature-related mortality than heat, with overall attributable fractions of 5.49% (95%CI: 3.82-7.19) and 0.81% (95%CI: 0.72-0.89), respectively. Future projections indicate that this pattern could be reversed under progressing global warming, with heat-related mortality starting to exceed cold-related mortality at 3 degrees C or higher GMT rise. Across cities, projected net increases in total temperature-related mortality were 0.45% (95%CI: -0.02-1.06) at 3 degrees C, 1.53% (95%CI: 0.96-2.06) at 4 degrees C, and 2.88% (95%CI: 1.60-4.10) at 5 degrees C, compared to today's warming level of 1 degrees C. By contrast, no significant difference was found between projected total temperature-related mortality at 2 degrees C versus 1 degrees C of GMT rise.
Conclusions: Our results can inform current adaptation policies aimed at buffering the health risks from increased heat exposure under climate change. They also allow for the evaluation of global mitigation efforts in terms of local health benefits in some of Germany's most populated cities.
KW - temperature-related mortality
KW - climate change
KW - Future projections
KW - Germany
KW - global mean temperature
Y1 - 2020
U6 - https://doi.org/10.1016/j.envres.2020.109447
SN - 0013-9351
SN - 1096-0953
VL - 186
SP - 1
EP - 10
PB - Elsevier
CY - San Diego, California
ER -
TY - JOUR
A1 - Stoof-Leichsenring, Kathleen Rosemarie
A1 - Pestryakova, Luidmila Agafyevna
A1 - Epp, Laura Saskia
A1 - Herzschuh, Ulrike
T1 - Phylogenetic diversity and environment form assembly rules for Arctic diatom genera
BT - a study on recent and ancient sedimentary DNA
JF - Journal of Biogeography
N2 - Aim This study investigates taxonomic and phylogenetic diversity in diatom genera to evaluate assembly rules for eukaryotic microbes across the Siberian tree line. We first analysed how phylogenetic distance relates to taxonomic richness and turnover. Second, we used relatedness indices to evaluate if environmental filtering or competition influences the assemblies in space and through time. Third, we used distance-based ordination to test which environmental variables shape diatom turnover. Location Yakutia and Taymyria, Russia: we sampled 78 surface sediments and a sediment core, extending to 7,000 years before present, to capture the forest-tundra transition in space and time respectively. Taxon Arctic freshwater diatoms. Methods We applied metabarcoding to retrieve diatom diversity from surface and core sedimentary DNA. The taxonomic assignment binned sequence types (lineages) into genera and created taxonomic (abundance of lineages within different genera) and phylogenetic datasets (phylogenetic distances of lineages within different genera). Results Contrary to our expectations, we find a unimodal relationship between phylogenetic distance and richness in diatom genera. We discern a positive relationship between phylogenetic distance and taxonomic turnover in spatially and temporally distributed diatom genera. Furthermore, we reveal positive relatedness indices in diatom genera across the spatial environmental gradient and predominantly in time slices at a single location, with very few exceptions assuming effects of competition. Distance-based ordination of taxonomic and phylogenetic turnover indicates that lake environment variables, like HCO3- and water depth, largely explain diatom turnover. Main conclusion Phylogenetic and abiotic assembly rules are important in understanding the regional assembly of diatom genera across lakes in the Siberian tree line ecotone. Using a space-time approach we are able to exclude the influence of geography and elucidate that lake environmental variables primarily shape the assemblies. We conclude that some diatom genera have greater capabilities to adapt to environmental changes, whereas others will be putatively replaced or lost due to the displacement of the Arctic tundra biome under recent global warming.
KW - ancient sedimentary DNA
KW - Arctic lakes
KW - assembly rules
KW - climate change
KW - diatoms
KW - environmental filtering
KW - phylogenetic diversity
KW - Siberian tree line
Y1 - 2020
U6 - https://doi.org/10.1111/jbi.13786
SN - 0305-0270
SN - 1365-2699
VL - 47
IS - 5
SP - 1166
EP - 1179
PB - Wiley-Blackwell
CY - Oxford
ER -
TY - JOUR
A1 - Hickmann, Thomas
A1 - Widerberg, Oscar
A1 - Lederer, Markus
A1 - Pattberg, Philipp H.
T1 - The United Nations Framework Convention on Climate Change Secretariat as an orchestrator in global climate policymaking
JF - International review of administrative sciences : an international journal of comparative public administration
N2 - Scholars have recently devoted increasing attention to the role and function of international bureaucracies in global policymaking. Some of them contend that international public officials have gained significant political influence in various policy fields. Compared to other international bureaucracies, the political leeway of the Secretariat of the United Nations Framework Convention on Climate Change has been considered rather limited. Due to the specific problem structure of the policy domain of climate change, national governments endowed this intergovernmental treaty secretariat with a relatively narrow mandate. However, this article argues that in the past few years, the United Nations Framework Convention on Climate Change Secretariat has gradually loosened its straitjacket and expanded its original spectrum of activity by engaging different sub-national and non-state actors into a policy dialogue using facilitative orchestration as a mode of governance. The present article explores the recent evolution of the United Nations Framework Convention on Climate Change Secretariat and investigates the way in which it initiates, guides, broadens and strengthens sub-national and non-state climate actions to achieve progress in the international climate negotiations.
Points for practitioners
The Secretariat of the United Nations Framework Convention on Climate Change has lately adopted new roles and functions in global climate policymaking. While previously seen as a rather technocratic body that, first and foremost, serves national governments, the Climate Secretariat increasingly interacts with sub-national governments, civil society organizations and private companies to push the global response to climate change forward. We contend that the Climate Secretariat can contribute to global climate policymaking by coordinating and steering the initiatives of non-nation-state actors towards coherence and good practice.
KW - climate change
KW - environmental policymaking
KW - intergovernmental relations
KW - international bureaucracies
KW - sub-national and non-state actors
Y1 - 2021
U6 - https://doi.org/10.1177/0020852319840425
SN - 0020-8523
SN - 1461-7226
VL - 87
IS - 1
SP - 21
EP - 38
PB - Sage
CY - Los Angeles, Calif. [u.a.]
ER -
TY - JOUR
A1 - Guzman Arias, Diego Alejandro
A1 - Samprogna Mohor, Guilherme
A1 - Mendiondo, Eduardo Mario
T1 - Multi-driver ensemble to evaluate the water utility business interruption cost induced by hydrological drought risk scenarios in Brazil
JF - Urban water journal
N2 - Climate change and increasing water demand in urban environments necessitate planning water utility companies' finances. Traditionally, methods to estimate the direct water utility business interruption costs (WUBIC) caused by droughts have not been clearly established. We propose a multi-driver assessment method. We project the water yield using a hydrological model driven by regional climate models under radiative forcing scenarios. We project water demand under stationary and non-stationary conditions to estimate drought severity and duration, which are linked with pricing policies recently adopted by the Sao Paulo Water Utility Company. The results showed water insecurity. The non-stationary trend imposed larger differences in the drought resilience financial gap, suggesting that the uncertainties of WUBIC derived from demand and climate models are greater than those associated with radiative forcing scenarios. As populations increase, proactively controlling demand is recommended to avoid or minimize reactive policy changes during future drought events, repeating recent financial impacts.
KW - Business interruption cost
KW - water utility company
KW - hydrological
KW - droughts
KW - water security
KW - urban water
KW - climate change
Y1 - 2022
U6 - https://doi.org/10.1080/1573062X.2022.2058564
SN - 1573-062X
SN - 1744-9006
PB - Routledge, Taylor & Francis Group
CY - Abingdon
ER -
TY - JOUR
A1 - Warszawski, Lila
A1 - Kriegler, Elmar
A1 - Lenton, Timothy M.
A1 - Gaffney, Owen
A1 - Jacob, Daniela
A1 - Klingenfeld, Daniel
A1 - Koide, Ryu
A1 - Costa, María Máñez
A1 - Messner, Dirk
A1 - Nakicenovic, Nebojsa
A1 - Schellnhuber, Hans Joachim
A1 - Schlosser, Peter
A1 - Takeuchi, Kazuhiko
A1 - van der Leeuw, Sander
A1 - Whiteman, Gail
A1 - Rockström, Johan
T1 - All options, not silver bullets, needed to limit global warming to 1.5 °C
BT - a scenario appraisal
JF - Environmental research letters
N2 - Climate science provides strong evidence of the necessity of limiting global warming to 1.5 °C, in line with the Paris Climate Agreement. The IPCC 1.5 °C special report (SR1.5) presents 414 emissions scenarios modelled for the report, of which around 50 are classified as '1.5 °C scenarios', with no or low temperature overshoot. These emission scenarios differ in their reliance on individual mitigation levers, including reduction of global energy demand, decarbonisation of energy production, development of land-management systems, and the pace and scale of deploying carbon dioxide removal (CDR) technologies. The reliance of 1.5 °C scenarios on these levers needs to be critically assessed in light of the potentials of the relevant technologies and roll-out plans. We use a set of five parameters to bundle and characterise the mitigation levers employed in the SR1.5 1.5 °C scenarios. For each of these levers, we draw on the literature to define 'medium' and 'high' upper bounds that delineate between their 'reasonable', 'challenging' and 'speculative' use by mid century. We do not find any 1.5 °C scenarios that stay within all medium upper bounds on the five mitigation levers. Scenarios most frequently 'over use' CDR with geological storage as a mitigation lever, whilst reductions of energy demand and carbon intensity of energy production are 'over used' less frequently. If we allow mitigation levers to be employed up to our high upper bounds, we are left with 22 of the SR1.5 1.5 °C scenarios with no or low overshoot. The scenarios that fulfil these criteria are characterised by greater coverage of the available mitigation levers than those scenarios that exceed at least one of the high upper bounds. When excluding the two scenarios that exceed the SR1.5 carbon budget for limiting global warming to 1.5 °C, this subset of 1.5 °C scenarios shows a range of 15–22 Gt CO2 (16–22 Gt CO2 interquartile range) for emissions in 2030. For the year of reaching net zero CO2 emissions the range is 2039–2061 (2049–2057 interquartile range).
KW - climate change
KW - emissions scenarios
KW - 1.5 ◦C
KW - negative emissions
Y1 - 2021
U6 - https://doi.org/10.1088/1748-9326/abfeec
SN - 1748-9326
N1 - Corrigendum: 10.1088/1748-9326/acbf6a
VL - 16
IS - 6
PB - IOP Publishing
CY - Bristol
ER -
TY - JOUR
A1 - Böhnke, Denise
A1 - Krehl, Alice
A1 - Moermann, Kai
A1 - Volk, Rebekka
A1 - Lützkendorf, Thomas
A1 - Naber, Elias
A1 - Becker, Ronja
A1 - Norra, Stefan
T1 - Mapping urban green and its ecosystem services at microscale-a methodological approach for climate adaptation and biodiversity
JF - Sustainability / Multidisciplinary Digital Publishing Institute (MDPI)
N2 - The current awareness of the high importance of urban green leads to a stronger need for tools to comprehensively represent urban green and its benefits. A common scientific approach is the development of urban ecosystem services (UES) based on remote sensing methods at the city or district level. Urban planning, however, requires fine-grained data that match local management practices. Hence, this study linked local biotope and tree mapping methods to the concept of ecosystem services. The methodology was tested in an inner-city district in SW Germany, comparing publicly accessible areas and non-accessible courtyards. The results provide area-specific [m(2)] information on the green inventory at the microscale, whereas derived stock and UES indicators form the basis for comparative analyses regarding climate adaptation and biodiversity. In the case study, there are ten times more micro-scale green spaces in private courtyards than in the public space, as well as twice as many trees. The approach transfers a scientific concept into municipal planning practice, enables the quantitative assessment of urban green at the microscale and illustrates the importance for green stock data in private areas to enhance decision support in urban development. Different aspects concerning data collection and data availability are critically discussed.
KW - climate adaptation
KW - urban green
KW - mapping
KW - ecosystem service cascade
KW - model
KW - surface type-function-concept
KW - planning indicators
KW - city district
KW - level
KW - urban planning practice
KW - climate change
Y1 - 2022
U6 - https://doi.org/10.3390/su14159029
SN - 2071-1050
VL - 14
IS - 15
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Sedova, Barbora
A1 - Kalkuhl, Matthias
A1 - Mendelsohn, Robert
T1 - Distributional impacts of weather and climate in rural India
JF - Economics of disasters and climate change
N2 - Climate-related costs and benefits may not be evenly distributed across the population. We study distributional implications of seasonal weather and climate on within-country inequality in rural India. Utilizing a first difference approach, we find that the poor are more sensitive to weather variations than the non-poor. The poor respond more strongly to (seasonal) temperature changes: negatively in the (warm) spring season, more positively in the (cold) rabi season. Less precipitation is harmful to the poor in the monsoon kharif season and beneficial in the winter and spring seasons. We show that adverse weather aggravates inequality by reducing consumption of the poor farming households. Future global warming predicted under RCP8.5 is likely to exacerbate these effects, reducing consumption of poor farming households by one third until the year 2100. We also find inequality in consumption across seasons with higher consumption during the harvest and lower consumption during the sowing seasons.
KW - climate change
KW - weather
KW - inequality
KW - household analysis
KW - India
KW - econometrics
Y1 - 2019
U6 - https://doi.org/10.1007/s41885-019-00051-1
SN - 2511-1280
SN - 2511-1299
VL - 4
IS - 1
SP - 5
EP - 44
PB - Springer
CY - Cham
ER -
TY - JOUR
A1 - Kalkuhl, Matthias
A1 - Wenz, Leonie
T1 - The impact of climate conditions on economic production
BT - evidence from a global panel of regions
JF - Journal of Environmental Economics and Management
N2 - We present a novel data set of subnational economic output, Gross Regional Product (GRP), for more than 1500 regions in 77 countries that allows us to empirically estimate historic climate impacts at different time scales. Employing annual panel models, long-difference regressions and cross-sectional regressions, we identify effects on productivity levels and productivity growth. We do not find evidence for permanent growth rate impacts but we find robust evidence that temperature affects productivity levels considerably. An increase in global mean surface temperature by about 3.5°C until the end of the century would reduce global output by 7–14% in 2100, with even higher damages in tropical and poor regions. Updating the DICE damage function with our estimates suggests that the social cost of carbon from temperature-induced productivity losses is on the order of 73–142$/tCO2 in 2020, rising to 92–181$/tCO2 in 2030. These numbers exclude non-market damages and damages from extreme weather events or sea-level rise.
KW - climate change
KW - climate damages
KW - climate impacts
KW - growth regression
KW - global warming
KW - panel regression
KW - cross-sectional regression
KW - damage
KW - function
KW - social costs of carbon
Y1 - 2020
U6 - https://doi.org/10.1016/j.jeem.2020.102360
SN - 0095-0696
SN - 1096-0449
VL - 103
PB - Elsevier
CY - San Diego
ER -
TY - JOUR
A1 - Schultes, Anselm
A1 - Piontek, Franziska
A1 - Soergel, Bjoern
A1 - Rogelj, Joeri
A1 - Baumstark, Lavinia
A1 - Kriegler, Elmar
A1 - Edenhofer, Ottmar
A1 - Luderer, Gunnar
T1 - Economic damages from on-going climate change imply deeper near-term emission cuts
JF - Environmental research letters
N2 - Pathways toward limiting global warming to well below 2 ∘C, as used by the IPCC in the Fifth Assessment Report, do not consider the climate impacts already occurring below 2 ∘C. Here we show that accounting for such damages significantly increases the near-term ambition of transformation pathways. We use econometric estimates of climate damages on GDP growth and explicitly model the uncertainty in the persistence time of damages. The Integrated Assessment Model we use includes the climate system and mitigation technology detail required to derive near-term policies. We find an optimal carbon price of $115 per tonne of CO2 in 2030. The long-term persistence of damages, while highly uncertain, is a main driver of the near-term carbon price. Accounting for damages on economic growth increases the gap between the currently pledged nationally determined contributions and the welfare-optimal 2030 emissions by two thirds, compared to pathways considering the 2 ∘C limit only.
KW - climate change
KW - climate mitigation
KW - climate impacts
KW - integrated assessment
Y1 - 2021
U6 - https://doi.org/10.1088/1748-9326/ac27ce
SN - 1748-9326
VL - 16
IS - 10
PB - IOP Publishing
CY - Bristol
ER -
TY - JOUR
A1 - Han, Sungju
A1 - Kuhlicke, Christian
T1 - Barriers and drivers for mainstreaming nature-based solutions for flood risks
BT - the case of South Korea
JF - International journal of disaster risk science
N2 - Nature-based solutions (NBS) are seen as a promising adaptation measure that sustainably deals with diverse societal challenges, while simultaneously delivering multiple benefits. Nature-based solutions have been highlighted as a resilient and sustainable means of mitigating floods and other hazards globally. This study examined diverging conceptualizations of NBS, as well as the attitudinal (for example, emotions and beliefs) and contextual (for example, legal and political aspects) barriers and drivers of NBS for flood risks in South Korea. Semistructured interviews were conducted with 11 experts and focused on the topic of flood risk measures and NBS case studies. The analysis found 11 barriers and five drivers in the attitudinal domain, and 13 barriers and two drivers in the contextual domain. Most experts see direct monetary benefits as an important attitudinal factor for the public. Meanwhile, the cost-effectiveness of NBS and their capacity to cope with flood risks were deemed influential factors that could lead decision makers to opt for NBS. Among the contextual factors, insufficient systems to integrate NBS in practice and the ideologicalization of NBS policy were found to be peculiar barriers, which hinder consistent realization of initiatives and a long-term national plan for NBS. Understanding the barriers and drivers related to the mainstreaming of NBS is critical if we are to make the most of such solutions for society and nature. It is also essential that we have a shared definition, expectation, and vision of NBS.
KW - climate change
KW - flood risk management
KW - nature-based solutions (NBS)
KW - South Korea
Y1 - 2021
U6 - https://doi.org/10.1007/s13753-021-00372-4
SN - 2095-0055
SN - 2192-6395
VL - 12
IS - 5
SP - 661
EP - 672
PB - Springer
CY - New York
ER -
TY - JOUR
A1 - Li, Zhen
A1 - Spangenberg, Erik
A1 - Schicks, Judith Maria
A1 - Kempka, Thomas
T1 - Numerical Simulation of Coastal Sub-Permafrost Gas Hydrate Formation in the Mackenzie Delta, Canadian Arctic
JF - Energies
N2 - The Mackenzie Delta (MD) is a permafrost-bearing region along the coasts of the Canadian Arctic which exhibits high sub-permafrost gas hydrate (GH) reserves. The GH occurring at the Mallik site in the MD is dominated by thermogenic methane (CH4), which migrated from deep conventional hydrocarbon reservoirs, very likely through the present fault systems. Therefore, it is assumed that fluid flow transports dissolved CH4 upward and out of the deeper overpressurized reservoirs via the existing polygonal fault system and then forms the GH accumulations in the Kugmallit-Mackenzie Bay Sequences. We investigate the feasibility of this mechanism with a thermo-hydraulic-chemical numerical model, representing a cross section of the Mallik site. We present the first simulations that consider permafrost formation and thawing, as well as the formation of GH accumulations sourced from the upward migrating CH4-rich formation fluid. The simulation results show that temperature distribution, as well as the thickness and base of the ice-bearing permafrost are consistent with corresponding field observations. The primary driver for the spatial GH distribution is the permeability of the host sediments. Thus, the hypothesis on GH formation by dissolved CH4 originating from deeper geological reservoirs is successfully validated. Furthermore, our results demonstrate that the permafrost has been substantially heated to 0.8-1.3 degrees C, triggered by the global temperature increase of about 0.44 degrees C and further enhanced by the Arctic Amplification effect at the Mallik site from the early 1970s to the mid-2000s.
KW - gas hydrate
KW - permafrost
KW - methane
KW - faults
KW - climate change
KW - Mallik
KW - numerical simulations
Y1 - 2022
U6 - https://doi.org/10.3390/en15144986
SN - 1996-1073
VL - 15
IS - 14
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Rolph, Rebecca
A1 - Overduin, Pier Paul
A1 - Ravens, Thomas
A1 - Lantuit, Hugues
A1 - Langer, Moritz
T1 - ArcticBeach v1.0
BT - a physics-based parameterization of pan-Arctic coastline erosion
JF - Frontiers in Earth Science
N2 - In the Arctic, air temperatures are increasing and sea ice is declining, resulting in larger waves and a longer open water season, all of which intensify the thaw and erosion of ice-rich coasts. Climate change has been shown to increase the rate of Arctic coastal erosion, causing problems for Arctic cultural heritage, existing industrial, military, and civil infrastructure, as well as changes in nearshore biogeochemistry. Numerical models that reproduce historical and project future Arctic erosion rates are necessary to understand how further climate change will affect these problems, and no such model yet exists to simulate the physics of erosion on a pan-Arctic scale. We have coupled a bathystrophic storm surge model to a simplified physical erosion model of a permafrost coastline. This Arctic erosion model, called ArcticBeach v1.0, is a first step toward a physical parameterization of Arctic shoreline erosion for larger-scale models. It is forced by wind speed and direction, wave period and height, sea surface temperature, all of which are masked during times of sea ice cover near the coastline. Model tuning requires observed historical retreat rates (at least one value), as well as rough nearshore bathymetry. These parameters are already available on a pan-Arctic scale. The model is validated at three study sites at 1) Drew Point (DP), Alaska, 2) Mamontovy Khayata (MK), Siberia, and 3) Veslebogen Cliffs, Svalbard. Simulated cumulative retreat rates for DP and MK respectively (169 and 170 m) over the time periods studied at each site (2007-2016, and 1995-2018) are found to the same order of magnitude as observed cumulative retreat (172 and 120 m). The rocky Veslebogen cliffs have small observed cumulative retreat rates (0.05 m over 2014-2016), and our model was also able to reproduce this same order of magnitude of retreat (0.08 m). Given the large differences in geomorphology between the study sites, this study provides a proof-of-concept that ArcticBeach v1.0 can be applied on very different permafrost coastlines. ArcticBeach v1.0 provides a promising starting point to project retreat of Arctic shorelines, or to evaluate historical retreat in places that have had few observations.
KW - permafrost
KW - erosion
KW - modelling
KW - arctic
KW - climate change
Y1 - 2022
U6 - https://doi.org/10.3389/feart.2022.962208
SN - 2296-6463
VL - 10
PB - Frontiers Media
CY - Lausanne
ER -
TY - JOUR
A1 - Guzman, Diego A.
A1 - Samprogna Mohor, Guilherme
A1 - Mendiondo, Eduardo Mario
T1 - Multi-year index-based insurance for adapting Water Utility Companies to hydrological drought
BT - case study of a water supply system of the Sao Paulo metropolitan region, Brazil
JF - Water
N2 - The sustainability of water utility companies is threatened by non-stationary drivers, such as climate and anthropogenic changes. To cope with potential economic losses, instruments such as insurance are useful for planning scenarios and mitigating impacts, but data limitations and risk uncertainties affect premium estimation and, consequently, business sustainability. This research estimated the possible economic impacts of business interruption to the Sao Paulo Water Utility Company derived from hydrological drought and how this could be mitigated with an insurance scheme. Multi-year insurance (MYI) was proposed through a set of "change" drivers: the climate driver, through forcing the water evaluation and planning system (WEAP) hydrological tool; the anthropogenic driver, through water demand projections; and the economic driver, associated with recent water price policies adopted by the utility company during water scarcity periods. In our study case, the evaluated indices showed that MYI contracts that cover only longer droughts, regardless of the magnitude, offer better financial performance than contracts that cover all events (in terms of drought duration). Moreover, through MYI contracts, we demonstrate solvency for the insurance fund in the long term and an annual average actuarially fair premium close to the total expected revenue reduction.
KW - multi-year insurance
KW - climate change
KW - hydrological drought
KW - water
KW - security and economy
Y1 - 2020
U6 - https://doi.org/10.3390/w12112954
SN - 2073-4441
VL - 12
IS - 11
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Sælen, Håkon
A1 - Hovi, Jon
A1 - Sprinz, Detlef F.
A1 - Underdal, Arild
T1 - How US withdrawal might influence cooperation under the Paris climate agreement
JF - Environmental science & policy
N2 - Using a novel agent-based model, we study how US withdrawal might influence the political process established by the Paris Agreement, and hence the prospects for reaching the collective goal to limit warming below 2 degrees C. Our model enables us to analyze to what extent reaching this goal despite US withdrawal would place more stringent requirements on other core elements of the Paris cooperation process. We find, first, that the effect of a US withdrawal depends critically on the extent to which member countries reciprocate others' promises and contributions. Second, while the 2 degrees C goal will likely be reached only under a very small set of conditions in any event, even temporary US withdrawal will further narrow this set significantly. Reaching this goal will then require other countries to step up their ambition at the first opportunity and to comply nearly 100% with their pledges, while maintaining high confidence in the Paris Agreements institutions. Third, although a US withdrawal will first primarily affect the United States' own emissions, it will eventually prove even more detrimental to other countries' emissions.
KW - climate change
KW - Paris agreement
KW - President Trump
KW - 2 degrees C target
KW - agent-based modeling
KW - reciprocity
Y1 - 2020
U6 - https://doi.org/10.1016/j.envsci.2020.03.011
SN - 1462-9011
SN - 1873-6416
VL - 108
SP - 121
EP - 132
PB - Elsevier
CY - Oxford
ER -
TY - JOUR
A1 - Mogrovejo Arias, Diana Carolina
A1 - Brill, Florian H. H.
A1 - Wagner, Dirk
T1 - Potentially pathogenic bacteria isolated from diverse habitats in Spitsbergen, Svalbard
JF - Environmental earth sciences
N2 - The Arctic ecosystem, a reservoir of genetic microbial diversity, represents a virtually unlimited source of microorganisms that could interact with human beings. Despite continuous exploration of Arctic habitats and description of their microbial communities, bacterial phenotypes commonly associated with pathogenicity, such as hemolytic activity, have rarely been reported. In this study, samples of snow, fresh and marine water, soil, and sediment from several habitats in the Arctic archipelago of Svalbard were collected during Summer, 2017. Bacterial isolates were obtained after incubation on oligotrophic media at different temperatures and their hemolytic potential was assessed on sheep blood agar plates. Partial (alpha) or true (beta) hemolysis was observed in 32 out of 78 bacterial species. Genes expressing cytolytic compounds, such as hemolysins, likely increase the general fitness of the producing microorganisms and confer a competitive advantage over the availability of nutrients in natural habitats. In environmental species, the nutrient-acquisition function of these compounds presumably precedes their function as toxins for mammalian erythrocytes. However, in the light of global warming, the presence of hemolytic bacteria in Arctic environments highlights the possible risks associated with these microorganisms in the event of habitat melting/destruction, ecosystem transition, and re-colonization.
KW - Arctic
KW - Svalbard
KW - hemolysins
KW - climate change
KW - pathogens
KW - virulence
Y1 - 2020
U6 - https://doi.org/10.1007/s12665-020-8853-4
SN - 1866-6280
SN - 1866-6299
VL - 79
IS - 5
PB - Springer
CY - Berlin ; Heidelberg
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 - Marzetz, Vanessa
A1 - Spijkerman, Elly
A1 - Striebel, Maren
A1 - Wacker, Alexander
T1 - Phytoplankton community responses to interactions between light intensity, light variations, and phosphorus supply
JF - Frontiers in Environmental Science
N2 - In a changing world, phytoplankton communities face a large variety of challenges including altered light regimes. These alterations are caused by more pronounced stratification due to rising temperatures, enhanced eutrophication, and browning of lakes. Community responses toward these effects can emerge as alterations in physiology, biomass, biochemical composition, or diversity. In this study, we addressed the combined effects of changes in light and nutrient conditions on community responses. In particular, we investigated how light intensity and variability under two nutrient conditions influence (1) fast responses such as adjustments in photosynthesis, (2) intermediate responses such as pigment adaptation and (3) slow responses such as changes in community biomass and species composition. Therefore, we exposed communities consisting of five phytoplankton species belonging to different taxonomic groups to two constant and two variable light intensity treatments combined with two levels of phosphorus supply. The tested phytoplankton communities exhibited increased fast reactions of photosynthetic processes to light variability and light intensity. The adjustment of their light harvesting mechanisms via community pigment composition was not affected by light intensity, variability, or nutrient supply. However, pigment specific effects of light intensity, light variability, and nutrient supply on the proportion of the respective pigments were detected. Biomass was positively affected by higher light intensity and nutrient concentrations while the direction of the effect of variability was modulated by light intensity. Light variability had a negative impact on biomass at low, but a positive impact at high light intensity. The effects on community composition were species specific. Generally, the proportion of green algae was higher under high light intensity, whereas the cyanobacterium performed better under low light conditions. In addition to that, the diatom and the cryptophyte performed better with high nutrient supply while the green algae as well as the cyanobacterium performed better at low nutrient conditions. This shows that light intensity, light variability, and nutrient supply interactively affect communities. Furthermore, the responses are highly species and pigment specific, thus to clarify the effects of climate change a deeper understanding of the effects of light variability and species interactions within communities is important.
KW - phytoplankton communities
KW - light variability
KW - photosynthetic rate
KW - climate change
KW - resource competition
KW - light intensity (irradiance)
KW - pigment composition
KW - nutrient supply
Y1 - 2020
U6 - https://doi.org/10.3389/fenvs.2020.539733
SN - 2296-665X
VL - 8
PB - Frontiers Media
CY - Lausanne
ER -
TY - JOUR
A1 - Wolf, Sabina
A1 - Pham, My
A1 - Matthews, Nathanial
A1 - Bubeck, Philip
T1 - Understanding the implementation gap
BT - policy-makers’ perceptions of ecosystem-based adaptation in Central Vietnam
JF - Climate & development
N2 - In recent years, nature-based solutions are receiving increasing attention in the field of disaster risk reduction and climate change adaptation as inclusive, no regret approaches. Ecosystem-based adaptation (EbA) can mitigate the impacts of climate change, build resilience and tackle environmental degradation thereby supporting the targets set by the 2030 Agenda, the Paris Agreement and the Sendai Framework. Despite these benefits, EbA is still rarely implemented in practice. To better understand the barriers to implementation, this research examines policy-makers' perceptions of EbA, using an extended version of Protection Motivation Theory as an analytical framework. Through semi-structured interviews with policy-makers at regional and provincial level in Central Vietnam, it was found that EbA is generally considered a promising response option, mainly due to its multiple ecosystem-service benefits. The demand for EbA measures was largely driven by the perceived consequences of natural hazards and climate change. Insufficient perceived response efficacy and time-lags in effectiveness for disaster risk reduction were identified as key impediments for implementation. Pilot projects and capacity building on EbA are important means to overcome these perceptual barriers. This paper contributes to bridging the knowledge-gap on political decision-making regarding EbA and can, thereby, promote its mainstreaming into policy plans.
KW - climate change
KW - ecosystem-based adaptation
KW - risk perception
KW - protection
KW - motivation theory
KW - decision making
Y1 - 2020
U6 - https://doi.org/10.1080/17565529.2020.1724068
SN - 1756-5529
SN - 1756-5537
VL - 13
IS - 1
SP - 81
EP - 94
PB - Taylor & Francis LTD
CY - Abingdon
ER -
TY - JOUR
A1 - Šedová, Barbora
A1 - Kalkuhl, Matthias
T1 - Who are the climate migrants and where do they go?
BT - Evidence from rural India
JF - World development
N2 - In this paper, we move from the large strand of research that looks at evidence of climate migration to the questions: who are the climate migrants? and where do they go? These questions are crucial to design policies that mitigate welfare losses of migration choices due to climate change. We study the direct and heterogeneous associations between weather extremes and migration in rural India. We combine ERAS reanalysis data with the India Human Development Survey household panel and conduct regression analyses by applying linear probability and multinomial logit models. This enables us to establish a causal relationship between temperature and precipitation anomalies and overall migration as well as migration by destination. We show that adverse weather shocks decrease rural-rural and international migration and push people into cities in different, presumably more prosperous states. A series of positive weather shocks, however, facilitates international migration and migration to cities within the same state. Further, our results indicate that in contrast to other migrants, climate migrants are likely to be from the lower end of the skill distribution and from households strongly dependent on agricultural production. We estimate that approximately 8% of all rural-urban moves between 2005 and 2012 can be attributed to weather. This figure might increase as a consequence of climate change. Thus, a key policy recommendation is to take steps to facilitate integration of less educated migrants into the urban labor market.
KW - climate change
KW - migration
KW - household analysis
KW - India
KW - econometrics
Y1 - 2020
U6 - https://doi.org/10.1016/j.worlddev.2019.104848
SN - 0305-750X
SN - 1873-5991
VL - 129
PB - Elsevier Science
CY - Amsterdam
ER -
TY - JOUR
A1 - Vindas-Picado, José
A1 - Yaney-Keller, Adam
A1 - St. Andrews, Laura
A1 - Panagopoulou, Aliki
A1 - Santidrián Tomillo, Pilar
T1 - Effectiveness of shading to mitigate the impact of high temperature on sea turtle clutches considering the effect on primary sex ratios
JF - Mitigation and adaptation strategies for global change : an international journal devoted to scientific, engineering, socio-economic and policy responses to environmental change
N2 - Developmental success of sea turtle clutches depends on incubation temperature, which also determines sex ratio of hatchlings. As global temperatures are rising, several studies have proposed mitigation strategies such as irrigation and shading to increase hatching success. Our study expands upon this research and measures the effects of using boxes with different degrees of shade coverage (50%, 80%, and 90%) on sand temperature and water content. Boxes were fully covered with fabric in 2017/2018 (top and sides) but were side open in 2018/2019. We took measurements at olive ridley (Lepidochelys olivacea) and leatherback (Dermochelys coriacea) turtle nest depths (45 and 75 cm) at Playa Grande, Costa Rica. Shading reduced temperature by up to 0.8 degrees C and up to 0.4 degrees C at 45 cm and 75 cm, respectively. There were statistically significant differences between shading and control treatments at both depths, but differences between shade treatments were only significant when using side open boxes, possibly due to air flow. Shading had no effect on water content. While the impact of using shaded boxes on temperature was low, the potential impact on primary sex ratios was large. If shading were applied to leatherback clutches, the percentage of female hatchlings could vary by up to 50%, with a maximum difference around the pivotal temperature (temperature with 1:1 sex ratio). Shading can be useful to increase hatching success, but we recommend avoiding it at temperatures within the transitional range (temperatures that produce both sexes), or using it only during the last third of incubation, when sex is already determined. As global warming will likely continue, understanding potential impact and effectiveness of mitigation strategies may be critical for the survival of threatened sea turtle populations.
KW - climate mitigation
KW - climate change
KW - hatchery
KW - hatching success
KW - TSD
Y1 - 2020
U6 - https://doi.org/10.1007/s11027-020-09932-3
SN - 1381-2386
SN - 1573-1596
VL - 25
IS - 8
SP - 1509
EP - 1521
PB - Springer
CY - Dordrecht
ER -
TY - JOUR
A1 - Ungelenk, Johannes
T1 - Émile Zola and the literary language of climate change
JF - Nottingham French studies / University of Nottingham
N2 - On 7 February 1861, John Tyndall, professor of natural philosophy, delivered a historical lecture: he could prove that different gases absorb heat to a very different degree, which implies that the temperate conditions provided for by the Earth's atmosphere are dependent on its particular composition of gases. The theoretical foundation of climate science was laid.
Ten years later, on the other side of the Channel, a young and ambitious author was working on a comprehensive literary analysis of the French era under the Second Empire. Émile Zola had probably not heard or read of Tyndall's discovery. However, the article makes the case for reading Zola's Rougon-Macquart as an extensive story of climate change. Zola's literary attempts to capture the defining characteristic of the Second Empire led him to the insight that its various milieus were all part of the same ‘climate’: that of an all-encompassing warming. Zola suggests that this climate is man-made: the economic success of the Second Empire is based on heating, in a literal and metaphorical sense, as well as on stoking the steam-engines and creating the hypertrophic atmosphere of the hothouse that enhances life and maximises turnover and profit. In contrast to Tyndall and his audience, Zola sensed the catastrophic consequences of this warming: the Second Empire was inevitably moving towards a final débâcle, i.e. it was doomed to perish in local and ‘global’ climate catastrophes.
The article foregrounds the supplementary status of Tyndall's physical and Zola's literary knowledge. As Zola's striking intuition demonstrates, literature appears to have a privileged approach to the phenomenon of man-induced climate change.
N2 - Le 7 février 1861, le professeur de philosophie naturelle John Tyndall donna une communication historique: il pouvait prouver que des gaz différents absorbent la chaleur de manière différente, ce qui implique que les conditions tempérées fournies par l’atmosphère terrestre dépendent de sa composition particulière en gaz. Le fondement théorique de la science climatique était posé. Dix ans plus tard, de l'autre côté du Channel, un jeune auteur ambitieux était en train de faire une analyse littéraire globale de la France du Second Empire. Émile Zola n'avait probablement pas entendu parler de la découverte de Tyndall. Cependant, cet article propose de lire les Rougon Macquart de Zola comme une vaste histoire du changement climatique. Les tentatives littéraires entreprises par Zola pour capturer la caractéristique déterminante du Second Empire l'amena à réaliser que ses différents milieux faisaient tous partie du même « climat »: celui d'un réchauffement global. Zola suggère que ce climat est créé par l'humain et que le succès économique du Second Empire est basé sur l'action de chauffer dans un sens littéral et métaphorique, ainsi que sur l'alimentation des machines à vapeur et la création de l'atmosphère hypertrophiée d'une serre qui enrichit la vie et maximise l'écoulement et le profit. Contrairement à Tyndall et à son auditoire, Zola pressentit les conséquences catastrophiques d'un tel réchauffement: le Second Empire s'approchait inévitablement d'une débâcle finale, c'est-à-dire qu'il était voué à périr dans des catastrophes locales et « globales ».
KW - Rougon-Macquart
KW - climate change
KW - John Tyndall
KW - global warming
KW - climate catastrophe
KW - Second Empire
KW - changement climatique
KW - réchauffement planétaire
KW - catastrophe climatique
KW - Rougon-Macquart
KW - Second Empire
KW - John Tyndall
Y1 - 2021
U6 - https://doi.org/10.3366/nfs.2021.0331
SN - 0029-4586
SN - 2047-7236
VL - 60
IS - 3
SP - 362
EP - 373
PB - Edinburgh University Press
CY - Edinburgh
ER -
TY - JOUR
A1 - Skålevåg, Amalie
A1 - Vormoor, Klaus Josef
T1 - Daily streamflow trends in Western versus Eastern Norway and their attribution to hydro-meteorological drivers
JF - Hydrological processes : an international journal
N2 - Regional warming and modifications in precipitation regimes has large impacts on streamflow in Norway, where both rainfall and snowmelt are important runoff generating processes. Hydrological impacts of recent changes in climate are usually investigated by trend analyses applied on annual, seasonal, or monthly time series. None of these detect sub-seasonal changes and their underlying causes. This study investigated sub-seasonal changes in streamflow, rainfall, and snowmelt in 61 and 51 catchments respectively in Western (Vestlandet) and Eastern (ostlandet) Norway by applying the Mann-Kendall test and Theil-Sen estimator on 10-day moving averaged daily time series over a 30-year period (1983-2012). The relative contribution of rainfall versus snowmelt to daily streamflow and the changes therein have also been estimated to identify the changing relevance of these driving processes over the same period. Detected changes in 10-day moving averaged daily streamflow were finally attributed to changes in the most important hydro-meteorological drivers using multiple-regression models with increasing complexity. Earlier spring flow timing in both regions occur due to earlier snowmelt. ostlandet shows increased summer streamflow in catchments up to 1100 m a.s.l. and slightly increased winter streamflow in about 50% of the catchments. Trend patterns in Vestlandet are less coherent. The importance of rainfall has increased in both regions. Attribution of trends reveals that changes in rainfall and snowmelt can explain some streamflow changes where they are dominant processes (e.g., spring snowmelt in ostlandet and autumn rainfall in Vestlandet). Overall, the detected streamflow changes can be best explained by adding temperature trends as an additional predictor, indicating the relevance of additional driving processes such as increased glacier melt and evapotranspiration.
KW - attribution
KW - climate change
KW - hydrological change
KW - hydro-meteorological
KW - driver
KW - streamflow trend
KW - trend analysis
Y1 - 2021
U6 - https://doi.org/10.1002/hyp.14329
SN - 0885-6087
SN - 1099-1085
VL - 35
IS - 8
PB - Wiley
CY - New York
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 - Pan, Xiaohui
A1 - Wang, Weishi
A1 - Liu, Tie
A1 - Huang, Yue
A1 - De Maeyer, Philippe
A1 - Guo, Chenyu
A1 - Ling, Yunan
A1 - Akmalov, Shamshodbek
T1 - Quantitative detection and attribution of groundwater level variations in the Amu Darya Delta
JF - Water
N2 - In the past few decades, the shrinkage of the Aral Sea is one of the biggest ecological catastrophes caused by human activity. To quantify the joint impact of both human activities and climate change on groundwater, the spatiotemporal groundwater dynamic characteristics in the Amu Darya Delta of the Aral Sea from 1999 to 2017 were analyzed, using the groundwater level, climate conditions, remote sensing data, and irrigation information. Statistics analysis was adopted to analyze the trend of groundwater variation, including intensity, periodicity, spatial structure, while the Pearson correlation analysis and principal component analysis (PCA) were used to quantify the impact of climate change and human activities on the variabilities of the groundwater level. Results reveal that the local groundwater dynamic has varied considerably. From 1999 to 2002, the groundwater level dropped from -189 cm to -350 cm. Until 2017, the groundwater level rose back to -211 cm with fluctuation. Seasonally, the fluctuation period of groundwater level and irrigation water was similar, both were about 18 months. Spatially, the groundwater level kept stable within the irrigation area and bare land but fluctuated drastically around the irrigation area. The Pearson correlation analysis reveals that the dynamic of the groundwater level is closely related to irrigation activity within the irrigation area (Nukus: -0.583), while for the place adjacent to the Aral Sea, the groundwater level is closely related to the Large Aral Sea water level (Muynak: 0.355). The results of PCA showed that the cumulative contribution rate of the first three components exceeds 85%. The study reveals that human activities have a great impact on groundwater, effective management, and the development of water resources in arid areas is an essential prerequisite for ecological protection.
KW - groundwater level variation
KW - climate change
KW - human activities
KW - statistical analysis
KW - Amu Darya Delta
Y1 - 2020
U6 - https://doi.org/10.3390/w12102869
SN - 2073-4441
VL - 12
IS - 10
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Tesselaar, Max
A1 - Botzen, W. J. Wouter
A1 - Haer, Toon
A1 - Hudson, Paul
A1 - Tiggeloven, Timothy
A1 - Aerts, Jeroen C. J. H.
T1 - Regional inequalities in flood insurance affordability and uptake under climate change
JF - Sustainability
N2 - Flood insurance coverage can enhance financial resilience of households to changing flood risk caused by climate change. However, income inequalities imply that not all households can afford flood insurance. The uptake of flood insurance in voluntary markets may decline when flood risk increases as a result of climate change. This increase in flood risk may cause substantially higher risk-based insurance premiums, reduce the willingness to purchase flood insurance, and worsen problems with the unaffordability of coverage for low-income households. A socio-economic tipping-point can occur when the functioning of a formal flood insurance system is hampered by diminishing demand for coverage. In this study, we examine whether such a tipping-point can occur in Europe for current flood insurance systems under different trends in future flood risk caused by climate and socio-economic change. This analysis gives insights into regional inequalities concerning the ability to continue to use flood insurance as an instrument to adapt to changing flood risk. For this study, we adapt the "Dynamic Integrated Flood and Insurance" (DIFI) model by integrating new flood risk simulations in the model that enable examining impacts from various scenarios of climate and socio-economic change on flood insurance premiums and consumer demand. Our results show rising unaffordability and declining demand for flood insurance across scenarios towards 2080. Under a high climate change scenario, simulations show the occurrence of a socio-economic tipping-point in several regions, where insurance uptake almost disappears. A tipping-point and related inequalities in the ability to use flood insurance as an adaptation instrument can be mitigated by introducing reforms of flood insurance arrangements.
KW - climate change
KW - flood risk management
KW - insurance
KW - socio-economic
KW - tipping-point
KW - adaptation
KW - partial equilibrium modeling
Y1 - 2020
U6 - https://doi.org/10.3390/su12208734
SN - 2071-1050
VL - 12
IS - 20
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Reibold, Kerstin
T1 - Settler Colonialism, Decolonization, and Climate Change
JF - Journal of applied philosophy
N2 - The article proposes that climate change makes enduring colonial injustices and structures visible. It focuses on the imposition and dominance of colonial concepts of land and self-determination on Indigenous peoples in settler states. It argues that if the dominance of these colonial frameworks remains unaddressed, the progressing climate change will worsen other colonial injustices, too. Specifically, Indigenous self-determination capabilities will be increasingly undermined, and Indigenous peoples will experience the loss of what they understand as relevant land from within their own ontologies of land. The article holds that even if settler states strive to repair colonial injustices, these efforts will be unsuccessful if climate change occurs and decolonization is pursued within the framework of a settler colonial ontology of land. Therefore, the article suggests, decolonization of the ontologies of land and concepts of self-determination is a precondition for a just response to climate change.
KW - territorial rights
KW - indigenous rights
KW - climate change
KW - colonialism
Y1 - 2022
U6 - https://doi.org/10.1111/japp.12573
SN - 0264-3758
SN - 1468-5930
PB - Wiley-Blackwell
CY - Oxford
ER -
TY - JOUR
A1 - Lecourieux, Fatma
A1 - Kappel, Christian
A1 - Pieri, Philippe
A1 - Charon, Justine
A1 - Pillet, Jeremy
A1 - Hilbert, Ghislaine
A1 - Renaud, Christel
A1 - Gomes, Eric
A1 - Delrot, Serge
A1 - Lecourieux, David
T1 - Dissecting the Biochemical and Transcriptomic Effects of a Locally Applied Heat Treatment on Developing Cabernet Sauvignon Grape Berries
JF - Frontiers in plant science
N2 - Reproductive development of grapevine and berry composition are both strongly influenced by temperature. To date, the molecular mechanisms involved in grapevine berries response to high temperatures are poorly understood. Unlike recent data that addressed the effects on berry development of elevated temperatures applied at the whole plant level, the present work particularly focuses on the fruit responses triggered by direct exposure to heat treatment (HT). In the context of climate change, this work focusing on temperature effect at the microclimate level is of particular interest as it can help to better understand the consequences of leaf removal (a common viticultural practice) on berry development. HT (+8 degrees C) was locally applied to clusters from Cabernet Sauvignon fruiting cuttings at three different developmental stages (middle green, veraison and middle ripening). Samples were collected 1, 7, and 14 days after treatment and used for metabolic and transcriptomic analyses. The results showed dramatic and specific biochemical and transcriptomic changes in heat exposed berries, depending on the developmental stage and the stress duration. When applied at the herbaceous stage, HT delayed the onset of veraison. Heating also strongly altered the berry concentration of amino acids and organic acids (e.g., phenylalanine, raminobutyric acid and malate) and decreased the anthocyanin content at maturity. These physiological alterations could be partly explained by the deep remodeling of transcriptome in heated berries. More than 7000 genes were deregulated in at least one of the nine experimental conditions. The most affected processes belong to the categories "stress responses," protein metabolism" and "secondary metabolism," highlighting the intrinsic capacity of grape berries to perceive HT and to build adaptive responses. Additionally, important changes in processes related to "transport," "hormone" and "cell wall" might contribute to the postponing of veraison. Finally, opposite effects depending on heating duration were observed for genes encoding enzymes of the general phenylpropanoid pathway, suggesting that the HI induced decrease in anthocyanin content may result from a combination of transcript abundance and product degradation.
KW - grapevine
KW - berry development
KW - microclimate
KW - high temperature
KW - microarrays
KW - metabolomics/metabolite profiling
KW - climate change
Y1 - 2017
U6 - https://doi.org/10.3389/fpls.2017.00053
SN - 1664-462X
VL - 8
PB - Frontiers Research Foundation
CY - Lausanne
ER -
TY - JOUR
A1 - Meißl, Gertraud
A1 - Formayer, Herbert
A1 - Klebinder, Klaus
A1 - Kerl, Florian
A1 - Schöberl, Friedrich
A1 - Geitner, Clemens
A1 - Markart, Gerhard
A1 - Leidinger, David
A1 - Bronstert, Axel
T1 - Climate change effects on hydrological system conditions influencing generation of storm runoff in small Alpine catchments
JF - Hydrological processes : an international journal
N2 - Floods and debris flows in small Alpine torrent catchments (<10km(2)) arise from a combination of critical antecedent system state conditions and mostly convective precipitation events with high precipitation intensities. Thus, climate change may influence the magnitude-frequency relationship of extreme events twofold: by a modification of the occurrence probabilities of critical hydrological system conditions and by a change of event precipitation characteristics. Three small Alpine catchments in different altitudes in Western Austria (Ruggbach, Brixenbach and Langentalbach catchment) were investigated by both field experiments and process-based simulation. Rainfall-runoff model (HQsim) runs driven by localized climate scenarios (CNRM-RM4.5/ARPEGE, MPI-REMO/ECHAM5 and ICTP-RegCM3/ECHAM5) were used in order to estimate future frequencies of stormflow triggering system state conditions. According to the differing altitudes of the study catchments, two effects of climate change on the hydrological systems can be observed. On one hand, the seasonal system state conditions of medium altitude catchments are most strongly affected by air temperature-controlled processes such as the development of the winter snow cover as well as evapotranspiration. On the other hand, the unglaciated high-altitude catchment is less sensitive to climate change-induced shifts regarding days with critical antecedent soil moisture and desiccated litter layer due to its elevation-related small proportion of sensitive areas. For the period 2071-2100, the number of days with critical antecedent soil moisture content will be significantly reduced to about 60% or even less in summer in all catchments. In contrast, the number of days with dried-out litter layers causing hydrophobic effects will increase by up to 8%-11% of the days in the two lower altitude catchments. The intensity analyses of heavy precipitation events indicate a clear increase in rain intensities of up to 10%.
KW - climate change
KW - hydrophobic effects
KW - small Alpine catchments
KW - soil moisture
KW - storm runoff events
KW - system conditions
Y1 - 2016
U6 - https://doi.org/10.1002/hyp.11104
SN - 0885-6087
SN - 1099-1085
VL - 31
IS - 6
SP - 1314
EP - 1330
PB - Wiley
CY - New York
ER -
TY - JOUR
A1 - Rybski, Diego
A1 - Reusser, Dominik Edwin
A1 - Winz, Anna-Lena
A1 - Fichtner, Christina
A1 - Sterzel, Till
A1 - Kropp, Jürgen
T1 - Cities as nuclei of sustainability?
JF - Environment and Planning B: Urban Analytics and City Science
N2 - We have assembled CO2 emission figures from collections of urban GHG emission estimates published in peer-reviewed journals or reports from research institutes and non-governmental organizations. Analyzing the scaling with population size, we find that the exponent is development dependent with a transition from super- to sub-linear scaling. From the climate change mitigation point of view, the results suggest that urbanization is desirable in developed countries. Further, we compare this analysis with a second scaling relation, namely the fundamental allometry between city population and area, and propose that density might be a decisive quantity too. Last, we derive the theoretical country-wide urban emissions by integration and obtain a dependence on the size of the largest city.
KW - Scaling
KW - cities
KW - climate change
KW - development process
KW - allometry
Y1 - 2017
U6 - https://doi.org/10.1177/0265813516638340
SN - 2399-8083
SN - 2399-8091
VL - 44
IS - 3
SP - 425
EP - 440
PB - Sage Publ.
CY - London
ER -
TY - JOUR
A1 - Ungelenk, Johannes
T1 - Émile Zola and the Literary Language of Climate Change
JF - Nottingham French Studies
N2 - On 7 February 1861, John Tyndall, professor of natural philosophy, delivered a historical lecture: he could prove that different gases absorb heat to a very different degree, which implies that the temperate conditions provided for by the Earth's atmosphere are dependent on its particular composition of gases. The theoretical foundation of climate science was laid.
Ten years later, on the other side of the Channel, a young and ambitious author was working on a comprehensive literary analysis of the French era under the Second Empire. Émile Zola had probably not heard or read of Tyndall's discovery. However, the article makes the case for reading Zola's Rougon-Macquart as an extensive story of climate change. Zola's literary attempts to capture the defining characteristic of the Second Empire led him to the insight that its various milieus were all part of the same ‘climate’: that of an all-encompassing warming. Zola suggests that this climate is man-made: the economic success of the Second Empire is based on heating, in a literal and metaphorical sense, as well as on stoking the steam-engines and creating the hypertrophic atmosphere of the hothouse that enhances life and maximises turnover and profit. In contrast to Tyndall and his audience, Zola sensed the catastrophic consequences of this warming: the Second Empire was inevitably moving towards a final débâcle, i.e. it was doomed to perish in local and ‘global’ climate catastrophes.
The article foregrounds the supplementary status of Tyndall's physical and Zola's literary knowledge. As Zola's striking intuition demonstrates, literature appears to have a privileged approach to the phenomenon of man-induced climate change.
N2 - Le 7 février 1861, le professeur de philosophie naturelle John Tyndall donna une communication historique: il pouvait prouver que des gaz différents absorbent la chaleur de manière différente, ce qui implique que les conditions tempérées fournies par l’atmosphère terrestre dépendent de sa composition particulière en gaz. Le fondement théorique de la science climatique était posé. Dix ans plus tard, de l'autre côté du Channel, un jeune auteur ambitieux était en train de faire une analyse littéraire globale de la France du Second Empire. Émile Zola n'avait probablement pas entendu parler de la découverte de Tyndall. Cependant, cet article propose de lire les Rougon Macquart de Zola comme une vaste histoire du changement climatique. Les tentatives littéraires entreprises par Zola pour capturer la caractéristique déterminante du Second Empire l'amena à réaliser que ses différents milieux faisaient tous partie du même « climat »: celui d'un réchauffement global. Zola suggère que ce climat est créé par l'humain et que le succès économique du Second Empire est basé sur l'action de chauffer dans un sens littéral et métaphorique, ainsi que sur l'alimentation des machines à vapeur et la création de l'atmosphère hypertrophiée d'une serre qui enrichit la vie et maximise l'écoulement et le profit. Contrairement à Tyndall et à son auditoire, Zola pressentit les conséquences catastrophiques d'un tel réchauffement: le Second Empire s'approchait inévitablement d'une débâcle finale, c'est-à-dire qu'il était voué à périr dans des catastrophes locales et « globales ».
KW - Rougon-Macquart
KW - climate change
KW - John Tyndall
KW - global warming
KW - climate catastrophe
KW - Second Empire
KW - changement climatique
KW - réchauffement planétaire
KW - catastrophe climatique
KW - Second Empire
Y1 - 2021
U6 - https://doi.org/https://doi.org/10.3366/nfs.2021.0331
VL - 60
IS - 3
SP - 362
EP - 373
ER -
TY - JOUR
A1 - Perring, Michael P.
A1 - Bernhardt-Roemermann, Markus
A1 - Baeten, Lander
A1 - Midolo, Gabriele
A1 - Blondeel, Haben
A1 - Depauw, Leen
A1 - Landuyt, Dries
A1 - Maes, Sybryn L.
A1 - De Lombaerde, Emiel
A1 - Caron, Maria Mercedes
A1 - Vellend, Mark
A1 - Brunet, Joerg
A1 - Chudomelova, Marketa
A1 - Decocq, Guillaume
A1 - Diekmann, Martin
A1 - Dirnboeck, Thomas
A1 - Doerfler, Inken
A1 - Durak, Tomasz
A1 - De Frenne, Pieter
A1 - Gilliam, Frank S.
A1 - Hedl, Radim
A1 - Heinken, Thilo
A1 - Hommel, Patrick
A1 - Jaroszewicz, Bogdan
A1 - Kirby, Keith J.
A1 - Kopecky, Martin
A1 - Lenoir, Jonathan
A1 - Li, Daijiang
A1 - Malis, Frantisek
A1 - Mitchell, Fraser J. G.
A1 - Naaf, Tobias
A1 - Newman, Miles
A1 - Petrik, Petr
A1 - Reczynska, Kamila
A1 - Schmidt, Wolfgang
A1 - Standovar, Tibor
A1 - Swierkosz, Krzysztof
A1 - Van Calster, Hans
A1 - Vild, Ondrej
A1 - Wagner, Eva Rosa
A1 - Wulf, Monika
A1 - Verheyen, Kris
T1 - Global environmental change effects on plant community composition trajectories depend upon management legacies
JF - Global change biology
N2 - The contemporary state of functional traits and species richness in plant communities depends on legacy effects of past disturbances. Whether temporal responses of community properties to current environmental changes are altered by such legacies is, however, unknown. We expect global environmental changes to interact with land-use legacies given different community trajectories initiated by prior management, and subsequent responses to altered resources and conditions. We tested this expectation for species richness and functional traits using 1814 survey-resurvey plot pairs of understorey communities from 40 European temperate forest datasets, syntheses of management transitions since the year 1800, and a trait database. We also examined how plant community indicators of resources and conditions changed in response to management legacies and environmental change. Community trajectories were clearly influenced by interactions between management legacies from over 200 years ago and environmental change. Importantly, higher rates of nitrogen deposition led to increased species richness and plant height in forests managed less intensively in 1800 (i.e., high forests), and to decreases in forests with a more intensive historical management in 1800 (i.e., coppiced forests). There was evidence that these declines in community variables in formerly coppiced forests were ameliorated by increased rates of temperature change between surveys. Responses were generally apparent regardless of sites’ contemporary management classifications, although sometimes the management transition itself, rather than historic or contemporary management types, better explained understorey responses. Main effects of environmental change were rare, although higher rates of precipitation change increased plant height, accompanied by increases in fertility indicator values. Analysis of indicator values suggested the importance of directly characterising resources and conditions to better understand legacy and environmental change effects. Accounting for legacies of past disturbance can reconcile contradictory literature results and appears crucial to anticipating future responses to global environmental change.
KW - biodiversity change
KW - climate change
KW - disturbance regime
KW - forestREplot
KW - herbaceous layer
KW - management intensity
KW - nitrogen deposition
KW - plant functional traits
KW - time lag
KW - vegetation resurvey
Y1 - 2017
U6 - https://doi.org/10.1111/gcb.14030
SN - 1354-1013
SN - 1365-2486
VL - 24
IS - 4
SP - 1722
EP - 1740
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Oguntunde, Philip G.
A1 - Abiodun, Babatunde Joseph
A1 - Lischeid, Gunnar
A1 - Abatan, Abayomi A.
T1 - Droughts projection over the Niger and Volta River basins of West Africa at specific global warming levels
JF - International Journal of Climatology
N2 - This study investigates possible impacts of four global warming levels (GWLs: GWL1.5, GWL2.0, GWL2.5, and GWL3.0) on drought characteristics over Niger River basin (NRB) and Volta River basin (VRB). Two drought indices-Standardized Precipitation Index (SPI) and Standardized Precipitation-Evapotranspiration Index (SPEI)-were employed in characterizing droughts in 20 multi-model simulation outputs from the Coordinated Regional Climate Downscaling Experiment (CORDEX). The performance of the simulation in reproducing basic hydro-climatological features and severe drought characteristics (i.e., magnitude and frequency) in the basins were evaluated. The projected changes in the future drought frequency were quantified and compared under the four GWLs for two climate forcing scenarios (RCP8.5 and RCP4.5). The regional climate model (RCM) ensemble gives a realistic simulation of historical hydro-climatological variables needed to calculate the drought indices. With SPEI, the simulation ensemble projects an increase in the magnitude and frequency of severe droughts over both basins (NRB and VRB) at all GWLs, but the increase, which grows with the GWLs, is higher over NRB than over VRB. More than 75% of the simulations agree on the projected increase at GWL1.5 and all simulations agree on the increase at higher GWLs. With SPI, the projected changes in severe drought is weaker and the magnitude remains the same at all GWLs, suggesting that SPI projection may underestimate impacts of the GWLs on the intensity and severity of future drought. The results of this study have application in mitigating impact of global warming on future drought risk over the regional water systems.
KW - climate change
KW - drought index
KW - global warming levels
KW - river basins
KW - West Africa
KW - CORDEX data
Y1 - 2019
VL - 40
IS - 13
PB - John Wiley & Sons, Inc.
CY - New Jersey
ER -
TY - JOUR
A1 - Huang, Xiaozhong
A1 - Peng, Wei
A1 - Rudaya, Natalia
A1 - Grimm, Eric C.
A1 - Chen, Xuemei
A1 - Cao, Xianyong
A1 - Zhang, Jun
A1 - Pan, Xiaoduo
A1 - Liu, Sisi
A1 - Chen, Chunzhu
A1 - Chen, Fahu
T1 - Holocene vegetation and climate dynamics in the Altai Mountains and Surrounding Areas
JF - Geophysical research letters
N2 - A comprehensive understanding of the regional vegetation responses to long-term climate change will help to forecast Earth system dynamics. Based on a new well-dated pollen data set from Kanas Lake and a review on the published pollen records in and around the Altai Mountains, the regional vegetation dynamics and forcing mechanisms are discussed. In the Altai Mountains, the forest optimum occurred during 10-7ka for the upper forest zone and the tree line decline and/or ecological shifts were caused by climatic cooling from around 7ka. In the lower forest zone, the forest reached an optimum in the middle Holocene, and then increased openness of the forest, possibly caused by both climate cooling and human activities, took place in the late Holocene. In the lower basins or plains around the Altai Mountains, the development of protograssland or forest benefited from increasing humidity in the middle to late Holocene. Plain Language Summary In the Altai Mountains and surrounding area of central Asia, the previous studies of the Holocene paleovegetation and paleoclimate studies did not discuss the different ecological limiting factors for the vegetation in high mountains and low-elevation areas due to limited data. With accumulating fossil pollen data and surface pollen data, it is possible to understand better the geomorphological effect on the vegetation and discrepancies of vegetation/forest responses to large-scale climate forcing, and it is also possible to get reliable quantitative reconstructions of climate. Here our new pollen data and review on the published fossil pollen data will help us to look into the past climate change and vertical evolution of vegetation in this important area of the Northern Hemisphere. Based on our study, it can be concluded that the growth of taiga forest in the wetter areas may be promoted under a future warmer climate, while the forest in the relatively dry areas is liable to decline, and the different vegetation dynamics will contribute to future high-resolution coupled vegetation-climate model for Earth system modelling.
KW - climate change
KW - Kanas Lake
KW - Altai Mountains
KW - vegetation dynamics
KW - taiga forest
Y1 - 2018
U6 - https://doi.org/10.1029/2018GL078028
SN - 0094-8276
SN - 1944-8007
VL - 45
IS - 13
SP - 6628
EP - 6636
PB - American Geophysical Union
CY - Washington
ER -
TY - JOUR
A1 - Grimm-Seyfarth, Annegret
A1 - Mihoub, Jean-Baptiste
A1 - Gruber, Bernd
A1 - Henle, Klaus
T1 - Some like it hot
BT - from individual to population responses of an arboreal arid-zone gecko to local and distant climate
JF - Ecological monographs
N2 - Accumulating evidence has demonstrated considerable impact of climate change on biodiversity, with terrestrial ectotherms being particularly vulnerable. While climate-induced range shifts are often addressed in the literature, little is known about the underlying ecological responses at individual and population levels. Using a 30-yr monitoring study of the long-living nocturnal gecko Gehyra variegata in arid Australia, we determined the relative contribution of climatic factors acting locally (temperature, rainfall) or distantly (La Nina induced flooding) on ecological processes ranging from traits at the individual level (body condition, body growth) to the demography at population level (survival, sexual maturity, population sizes). We also investigated whether thermoregulatory activity during both active (night) and resting (daytime) periods of the day can explain these responses. Gehyra variegata responded to local and distant climatic effects. Both high temperatures and high water availability enhanced individual and demographic parameters. Moreover, the impact of water availability was scale independent as local rainfall and La Nina induced flooding compensated each other. When water availability was low, however, extremely high temperatures delayed body growth and sexual maturity while survival of individuals and population sizes remained stable. This suggests a trade-off with traits at the individual level that may potentially buffer the consequences of adverse climatic conditions at the population level. Moreover, hot temperatures did not impact nocturnal nor diurnal behavior. Instead, only cool temperatures induced diurnal thermoregulatory behavior with individuals moving to exposed hollow branches and even outside tree hollows for sun-basking during the day. Since diurnal behavioral thermoregulation likely induced costs on fitness, this could decrease performance at both individual and population level under cool temperatures. Our findings show that water availability rather than high temperature is the limiting factor in our focal population of G.variegata. In contrast to previous studies, we stress that drier rather than warmer conditions are expected to be detrimental for nocturnal desert reptiles. Identifying the actual limiting climatic factors at different scales and their functional interactions at different ecological levels is critical to be able to predict reliably future population dynamics and support conservation planning in arid ecosystems.
KW - behavioral adaptation
KW - body condition
KW - body growth rate
KW - climate change
KW - El Nino Southern Oscillation (ENSO)
KW - Gehyra variegata
KW - population dynamics
KW - population size
KW - survival
KW - thermoregulation
Y1 - 2018
U6 - https://doi.org/10.1002/ecm.1301
SN - 0012-9615
SN - 1557-7015
VL - 88
IS - 3
SP - 336
EP - 352
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - van Kleunen, Mark
A1 - Essl, Franz
A1 - Pergl, Jan
A1 - Brundu, Giuseppe
A1 - Carboni, Marta
A1 - Dullinger, Stefan
A1 - Early, Regan
A1 - Gonzalez-Moreno, Pablo
A1 - Groom, Quentin J. M.
A1 - Hulme, Philip E.
A1 - Kueffer, Christoph
A1 - Kühn, Ingolf
A1 - Maguas, Cristina
A1 - Maurel, Noelie
A1 - Novoa, Ana
A1 - Parepa, Madalin
A1 - Pysek, Petr
A1 - Seebens, Hanno
A1 - Tanner, Rob
A1 - Touza, Julia
A1 - Verbrugge, Laura
A1 - Weber, Ewald
A1 - Dawson, Wayne
A1 - Kreft, Holger
A1 - Weigelt, Patrick
A1 - Winter, Marten
A1 - Klonner, Guenther
A1 - Talluto, Matthew V.
A1 - Dehnen-Schmutz, Katharina
T1 - The changing role of ornamental horticulture in alien plant invasions
JF - Biological reviews
N2 - The number of alien plants escaping from cultivation into native ecosystems is increasing steadily. We provide an overview of the historical, contemporary and potential future roles of ornamental horticulture in plant invasions. We show that currently at least 75% and 93% of the global naturalised alien flora is grown in domestic and botanical gardens, respectively. Species grown in gardens also have a larger naturalised range than those that are not. After the Middle Ages, particularly in the 18th and 19th centuries, a global trade network in plants emerged. Since then, cultivated alien species also started to appear in the wild more frequently than non-cultivated aliens globally, particularly during the 19th century. Horticulture still plays a prominent role in current plant introduction, and the monetary value of live-plant imports in different parts of the world is steadily increasing. Historically, botanical gardens - an important component of horticulture - played a major role in displaying, cultivating and distributing new plant discoveries. While the role of botanical gardens in the horticultural supply chain has declined, they are still a significant link, with one-third of institutions involved in retail-plant sales and horticultural research. However, botanical gardens have also become more dependent on commercial nurseries as plant sources, particularly in North America. Plants selected for ornamental purposes are not a random selection of the global flora, and some of the plant characteristics promoted through horticulture, such as fast growth, also promote invasion. Efforts to breed non-invasive plant cultivars are still rare. Socio-economical, technological, and environmental changes will lead to novel patterns of plant introductions and invasion opportunities for the species that are already cultivated. We describe the role that horticulture could play in mediating these changes. We identify current research challenges, and call for more research efforts on the past and current role of horticulture in plant invasions. This is required to develop science-based regulatory frameworks to prevent further plant invasions.
KW - botanical gardens
KW - climate change
KW - horticulture
KW - naturalised plants
KW - ornamental plants
KW - pathways
KW - plant invasions
KW - plant nurseries
KW - trade
KW - weeds
Y1 - 2018
U6 - https://doi.org/10.1111/brv.12402
SN - 1464-7931
SN - 1469-185X
VL - 93
IS - 3
SP - 1421
EP - 1437
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Steffen, Will
A1 - Röckstrom, Johan
A1 - Richardson, Katherine
A1 - Lenton, Timothy M.
A1 - Folke, Carl
A1 - Liverman, Diana
A1 - Summerhayes, Colin P.
A1 - Barnosky, Anthony D.
A1 - Cornell, Sarah E.
A1 - Crucifix, Michel
A1 - Donges, Jonathan
A1 - Fetzer, Ingo
A1 - Lade, Steven J.
A1 - Scheffer, Marten
A1 - Winkelmann, Ricarda
A1 - Schellnhuber, Hans Joachim
T1 - Trajectories of the Earth System in the Anthropocene
JF - Proceedings of the National Academy of Sciences of the United States of America
N2 - We explore the risk that self-reinforcing feedbacks could push the Earth System toward a planetary threshold that, if crossed, could prevent stabilization of the climate at intermediate temperature rises and cause continued warming on a "Hothouse Earth" pathway even as human emissions are reduced. Crossing the threshold would lead to a much higher global average temperature than any interglacial in the past 1.2 million years and to sea levels significantly higher than at any time in the Holocene. We examine the evidence that such a threshold might exist and where it might be. If the threshold is crossed, the resulting trajectory would likely cause serious disruptions to ecosystems, society, and economies. Collective human action is required to steer the Earth System away from a potential threshold and stabilize it in a habitable interglacial-like state. Such action entails stewardship of the entire Earth System-biosphere, climate, and societies-and could include decarbonization of the global economy, enhancement of biosphere carbon sinks, behavioral changes, technological innovations, new governance arrangements, and transformed social values.
KW - Earth System trajectories
KW - climate change
KW - Anthropocene
KW - biosphere feedbacks
KW - tipping elements
Y1 - 2018
U6 - https://doi.org/10.1073/pnas.1810141115
SN - 0027-8424
VL - 115
IS - 33
SP - 8252
EP - 8259
PB - National Acad. of Sciences
CY - Washington
ER -
TY - JOUR
A1 - Tape, Ken D.
A1 - Jones, Benjamin M.
A1 - Arp, Christopher D.
A1 - Nitze, Ingmar
A1 - Grosse, Guido
T1 - Tundra be dammed
BT - beaver colonization of the arctic
JF - Global change biology
N2 - Increasing air temperatures are changing the arctic tundra biome. Permafrost is thawing, snow duration is decreasing, shrub vegetation is proliferating, and boreal wildlife is encroaching. Here we present evidence of the recent range expansion of North American beaver (Castor canadensis) into the Arctic, and consider how this ecosystem engineer might reshape the landscape, biodiversity, and ecosystem processes. We developed a remote sensing approach that maps formation and disappearance of ponds associated with beaver activity. Since 1999, 56 new beaver pond complexes were identified, indicating that beavers are colonizing a predominantly tundra region (18,293km(2)) of northwest Alaska. It is unclear how improved tundra stream habitat, population rebound following overtrapping for furs, or other factors are contributing to beaver range expansion. We discuss rates and likely routes of tundra beaver colonization, as well as effects on permafrost, stream ice regimes, and freshwater and riparian habitat. Beaver ponds and associated hydrologic changes are thawing permafrost. Pond formation increases winter water temperatures in the pond and downstream, likely creating new and more varied aquatic habitat, but specific biological implications are unknown. Beavers create dynamic wetlands and are agents of disturbance that may enhance ecosystem responses to warming in the Arctic.
KW - arctic tundra
KW - beaver
KW - climate change
KW - permafrost
KW - population recovery
KW - salmon
KW - shrub expansion
KW - stream
Y1 - 2018
U6 - https://doi.org/10.1111/gcb.14332
SN - 1354-1013
SN - 1365-2486
VL - 24
IS - 10
SP - 4478
EP - 4488
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Coch, Caroline
A1 - Lamoureux, Scott F.
A1 - Knoblauch, Christian
A1 - Eischeid, Isabell
A1 - Fritz, Michael
A1 - Obu, Jaroslav
A1 - Lantuit, Hugues
T1 - Summer rainfall dissolved organic carbon, solute, and sediment fluxes in a small Arctic coastal catchment on Herschel Island (Yukon Territory, Canada)
JF - Artic science
N2 - Coastal ecosystems in the Arctic are affected by climate change. As summer rainfall frequency and intensity are projected to increase in the future, more organic matter, nutrients and sediment could bemobilized and transported into the coastal nearshore zones. However, knowledge of current processes and future changes is limited. We investigated streamflow dynamics and the impacts of summer rainfall on lateral fluxes in a small coastal catchment on Herschel Island in the western Canadian Arctic. For the summer monitoring periods of 2014-2016, mean dissolved organic matter flux over 17 days amounted to 82.7 +/- 30.7 kg km(-2) and mean total dissolved solids flux to 5252 +/- 1224 kg km(-2). Flux of suspended sediment was 7245 kg km(-2) in 2015, and 369 kg km(-2) in 2016. We found that 2.0% of suspended sediment was composed of particulate organic carbon. Data and hysteresis analysis suggest a limited supply of sediments; their interannual variability is most likely caused by short-lived localized disturbances. In contrast, our results imply that dissolved organic carbon is widely available throughout the catchment and exhibits positive linear relationship with runoff. We hypothesize that increased projected rainfall in the future will result in a similar increase of dissolved organic carbon fluxes.
KW - permafrost
KW - hydrology
KW - lateral fluxes
KW - hysteresis
KW - climate change
Y1 - 2018
U6 - https://doi.org/10.1139/as-2018-0010
SN - 2368-7460
VL - 4
IS - 4
SP - 750
EP - 780
PB - Canadian science publishing
CY - Ottawa
ER -
TY - JOUR
A1 - Tabares Jimenez, Ximena del Carmen
A1 - Zimmermann, Heike Hildegard
A1 - Dietze, Elisabeth
A1 - Ratzmann, Gregor
A1 - Belz, Lukas
A1 - Vieth-Hillebrand, Andrea
A1 - Dupont, Lydie
A1 - Wilkes, Heinz
A1 - Mapani, Benjamin
A1 - Herzschuh, Ulrike
T1 - Vegetation state changes in the course of shrub encroachment in an African savanna since about 1850 CE and their potential drivers
JF - Ecology and evolution
N2 - Shrub encroachment has far-reaching ecological and economic consequences in many ecosystems worldwide. Yet, compositional changes associated with shrub encroachment are often overlooked despite having important effects on ecosystem functioning. We document the compositional change and potential drivers for a northern Namibian Combretum woodland transitioning into a Terminalia shrubland. We use a multiproxy record (pollen, sedimentary ancient DNA, biomarkers, compound-specific carbon (delta C-13) and deuterium (delta D) isotopes, bulk carbon isotopes (delta(13)Corg), grain size, geochemical properties) from Lake Otjikoto at high taxonomical and temporal resolution. We provide evidence that state changes in semiarid environments may occur on a scale of one century and that transitions between stable states can span around 80 years and are characterized by a unique vegetation composition. We demonstrate that the current grass/woody ratio is exceptional for the last 170 years, as supported by n-alkane distributions and the delta C-13 and delta(13)Corg records. Comparing vegetation records to environmental proxy data and census data, we infer a complex network of global and local drivers of vegetation change. While our delta D record suggests physiological adaptations of woody species to higher atmospheric pCO(2) concentration and drought, our vegetation records reflect the impact of broad-scale logging for the mining industry, and the macrocharcoal record suggests a decrease in fire activity associated with the intensification of farming. Impact of selective grazing is reflected by changes in abundance and taxonomical composition of grasses and by an increase of nonpalatable and trampling-resistant taxa. In addition, grain-size and spore records suggest changes in the erodibility of soils because of reduced grass cover. Synthesis. We conclude that transitions to an encroached savanna state are supported by gradual environmental changes induced by management strategies, which affected the resilience of savanna ecosystems. In addition, feedback mechanisms that reflect the interplay between management legacies and climate change maintain the encroached state.
KW - climate change
KW - fossil pollen
KW - land-use change
KW - savanna ecology
KW - sedimentary ancient DNA
KW - state and transition
KW - tree-grass interactions
Y1 - 2019
U6 - https://doi.org/10.1002/ece3.5955
SN - 2045-7758
VL - 10
IS - 2
SP - 962
EP - 979
PB - Wiley
CY - Hoboken
ER -