TY  - JOUR
A1  - Öztürk, Ugur
A1  - Bozzolan, Elisa
A1  - Holcombe, Elizabeth A.
A1  - Shukla, Roopam
A1  - Pianosi, Francesca
A1  - Wagener, Thorsten
T1  - How climate change and unplanned urban sprawl bring more landslides
JF  - Nature : the international weekly journal of science
N2  - More settlements will suffer as heavy rains and unregulated construction destabilize slopes in the tropics, models show.
KW  - Geophysics
KW  - Engineering
KW  - Climate change
KW  - Policy
Y1  - 2022
U6  - https://doi.org/10.1038/d41586-022-02141-9
SN  - 0028-0836
SN  - 1476-4687
VL  - 608
IS  - 7922
SP  - 262
EP  - 265
PB  - Nature portfolio
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Yair, Aaron
A1  - Bryan, Rorke B.
A1  - Lavee, Hanoch
A1  - Schwanghart, Wolfgang
A1  - Kuhn, Nikolaus J.
T1  - The resilience of a badland area to climate change in an arid environment
JF  - Catena : an interdisciplinary journal of soil science, hydrology, geomorphology focusing on geoecology and landscape evolution
N2  - Badlands have long been considered as model landscapes due to their perceived close relationship between form and process. The often intense features of erosion have also attracted many geomorphologists because the associated high rates of erosion appeared to offer the opportunity for studying surface processes and the resulting forms. Recently, the perceived simplicity of badlands has been questioned because the expected relationships between driving forces for erosion and the resulting sediment yield could not be observed. Further, a high variability in erosion and sediment yield has been observed across scales. Finally, denudation based on currently observed erosion rates would have lead to the destruction of most badlands a long time ago. While the perceived simplicity of badlands has sparked a disproportional (compared to the land surface they cover) amount of research, our increasing amount of information has not necessarily increased our understanding of badlands in equal terms. Overall, badlands appear to be more complex than initially assumed. In this paper, we review 40 years of research in the Zin Valley Badlands in Israel to reconcile some of the conflicting results observed there and develop a perspective on the function of badlands as model landscapes. While the data collected in the Zin Valley clearly confirm that spatial and temporal patterns of geomorphic processes and their interaction with topography and surface properties have to be understood, we still conclude that the process of realizing complexity in the "simple" badlands has a model function both for our understanding as well as perspective on all landscape systems.
KW  - Badlands
KW  - Model landscape
KW  - Climate change
KW  - Resilience
Y1  - 2013
U6  - https://doi.org/10.1016/j.catena.2012.04.006
SN  - 0341-8162
VL  - 106
IS  - 4
SP  - 12
EP  - 21
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wischnewski, Juliane
A1  - Mackay, Anson W.
A1  - Appleby, Peter G.
A1  - Mischke, Steffen
A1  - Herzschuh, Ulrike
T1  - Modest diatom responses to regional warming on the southeast Tibetan Plateau during the last two centuries
JF  - Journal of paleolimnolog
N2  - A general mean annual temperature increase accompanied with substantial glacial retreat has been noted on the Tibetan Plateau during the last two centuries but most significantly since the mid 1950s. These climate trends are particularly apparent on the southeastern Tibetan Plateau. However, the Tibetan Plateau (due to its heterogeneous mountain landscape) has very complex and spatially differing temperature and precipitations patterns. As a result, intensive palaeolimnological investigations are necessary to decipher these climatic patterns and to understand ecological responses to recent environmental change. Here we present palaeolimnological results from a (210)Pb/(137)Cs-dated sediment core spanning approximately the last 200 years from a remote high-mountain lake (LC6 Lake, working name) on the southeastern Tibetan Plateau. Sediment profiles of diatoms, organic variables (TOC, C:N) and grain size were investigated. The (210)Pb record suggests a period of rapid sedimentation, which might be linked to major tectonic events in the region ca. 1950. Furthermore, unusually high (210)Pb supply rates over the last 50 years suggest that the lake has possibly been subjected to increasing precipitation rates, sediment focussing and/or increased spring thaw. The majority of diatom taxa encountered in the core are typical of slightly acidic to circumneutral, oligotrophic, electrolyte-poor lakes. Diatom species assemblages were rich, and dominated by Cyclotella sp., Achnanthes sp., Aulacoseira sp. and fragilarioid taxa. Diatom compositional change was minimal over the 200-year period (DCCA = 0.85 SD, p = 0.59); only a slightly more diverse but unstable diatom assemblage was recorded during the past 50 years. The results indicate that large-scale environmental changes recorded in the twentieth century (i.e. increased precipitation and temperatures) are likely having an affect on the LC6 Lake, but so far these impacts are more apparent on the lake geochemistry than on the diatom flora. Local and/or regional peculiarities, such as increasing precipitation and cloud cover, or localized climatic phenomena, such as negative climate feedbacks, might have offset the effects of increasing mean surface temperatures.
KW  - Diatoms
KW  - Tibetan Plateau
KW  - Mountain lake
KW  - Climate change
KW  - Lake sediments
KW  - Palaeolimnology
Y1  - 2011
U6  - https://doi.org/10.1007/s10933-011-9533-x
SN  - 0921-2728
VL  - 46
IS  - 2
SP  - 215
EP  - 227
PB  - Springer
CY  - Dordrecht
ER  - 
TY  - JOUR
A1  - Wischnewski, Juliane
A1  - Herzschuh, Ulrike
A1  - Ruehland, Kathleen M.
A1  - Braeuning, Achim
A1  - Mischke, Steffen
A1  - Smol, John P.
A1  - Wang, Lily
T1  - Recent ecological responses to climate variability and human impacts in the Nianbaoyeze Mountains (eastern Tibetan Plateau) inferred from pollen, diatom and tree-ring data
JF  - Journal of paleolimnolog
N2  - The Tibetan Plateau is a region that is highly sensitive to recent global warming, but the complexity and heterogeneity of its mountainous landscape can result in variable responses. In addition, the scarcity and brevity of regional instrumental and palaeoecological records still hamper our understanding of past and present patterns of environmental change. To investigate how the remote, high-alpine environments of the Nianbaoyeze Mountains, eastern Tibetan Plateau, are affected by climate change and human activity over the last similar to 600 years, we compared regional tree-ring studies with pollen and diatom remains archived in the dated sediments of Dongerwuka Lake (33.22A degrees N, 101.12A degrees E, 4,307 m a.s.l.). In agreement with previous studies from the eastern Tibetan Plateau, a strong coherence between our two juniper-based tree-ring chronologies from the Nianbaoyeze and the Anemaqin Mountains was observed, with pronounced cyclical variations in summer temperature reconstructions. A positive directional trend to warmer summer temperatures in the most recent decades, was, however, not observed in the tree-ring record. Likewise, our pollen and diatom spectra showed minimal change over the investigated time period. Although modest, the most notable change in the diatom relative abundances was a subtle decrease in the dominant planktonic Cyclotella ocellata and a concurrent increase in small, benthic fragilarioid taxa in the similar to 1820s, suggesting higher ecosystem variability. The pollen record subtly indicates three periods of increased cattle grazing activity (similar to 1400-1480 AD, similar to 1630-1760 AD, after 1850 AD), but shows generally no significant vegetation changes during past similar to 600 years. The minimal changes observed in the tree-ring, diatom and pollen records are consistent with the presence of localised cooling centres that are evident in instrumental and tree-ring data within the southeastern and eastern Tibetan Plateau. Given the minor changes in regional temperature records, our complacent palaeoecological profiles suggest that climatically induced ecological thresholds have not yet been crossed in the Nianbaoyeze Mountains region.
KW  - Tibetan Plateau
KW  - Nianbaoyeze Mountains
KW  - Pollen
KW  - Diatoms
KW  - Tree-ring
KW  - Climate change
KW  - Human impact
Y1  - 2014
U6  - https://doi.org/10.1007/s10933-013-9747-1
SN  - 0921-2728
SN  - 1573-0417
VL  - 51
IS  - 2
SP  - 287
EP  - 302
PB  - Springer
CY  - Dordrecht
ER  - 
TY  - THES
A1  - Wilhelm, Susann
T1  - Climate induced impacts on lake functioning in summer
T1  - Auswirkungen des Klimawandels auf Seen im Sommer
N2  - Es gibt bereits viele Hinweise dafür, dass Seen sehr sensibel auf die anthropogen verursachte Klimaerwärmung reagiert haben. Bis jetzt haben sich die Studien der Klimafolgenforschung hauptsächlichst auf die Auswirkungen der Erwärmung im Winter und Frühling konzentriert. Über den Einfluss der Klimaerwärmung auf Seen in den gemäßigten Breiten im Sommer ist weniger bekannt. In der vorliegenden Doktorarbeit habe ich einige Faktoren, welche die Reaktion von Seen auf die Erwärmung im Sommer vermutlich stark mitbestimmt haben, untersucht. Der Schwerpunkt lag dabei auf klimatisch induzierten Auswirkungen auf die thermische Charakteristik und die Phänologie und Abundanz des Planktons eines flachen und polymiktischen Sees (Müggelsee, Berlin). Zuerst wurde der Einfluss der Klimaerwärmung auf die Phänologie und Abundanz des Planktons in verschiedenen Jahreszeiten untersucht. Das schnellwachsende Phyto- und Zooplankton (Daphnia) im Frühjahr hat sich vorwiegend synchron vorverschoben, wohingegen Veränderungen des Sommerzooplanktons deutlich artspezifisch und nicht synchron waren. Die Phänologie oder Abundanz einiger Sommercopepoden hat sich entsprechend der individuellen thermischen Anforderungen innerhalb bestimmter Entwicklungsstufen, wie zum Beispiel der Emergenz von der Diapause im Frühling, verändert. Die Studie unterstreicht, dass nicht nur der Grad der Erwärmung, sondern auch dessen Zeitpunkt innerhalb des Jahres von großer ökologischer Bedeutung ist. Um die Auswirkungen des Klimawandels auf die thermischen Eigenschaften des Sees zu erforschen, habe ich die Langzeitentwicklung der täglichen epilimnischen Temperaturextrema während des Sommers untersucht. Durch diese Studie wurde zum ersten Mal für Seen gezeigt, dass die täglichen epilimnischen Minima (Nacht) stärker angestiegen sind als die Maxima (Tag), wodurch sich der tägliche epilimnische Temperaturbereich deutlich verringert hat. Diese Tag-Nacht-Asymmetrie in der epilimnischen Temperatur wurde durch eine erhöhte Emission von Langwellenstrahlung aus der Atmosphäre während der Nacht verursacht. Dies unterstreicht, dass nicht nur Erhöhungen der Lufttemperatur, sondern auch Änderungen anderer meteorologischer Variablen wie der Windgeschwindigkeit, der Luftfeuchte und der Bewölkung eine wichtige Rolle bei der Bestimmung der Seetemperatur im Hinblick auf weitere Klimaveränderungen spielen werden. Zudem wurde eine Kurzzeitanalyse zum Schichtungsverhalten des polymiktischen Sees durchgeführt, um die Häufigkeit und Dauer von Schichtungsereignissen und deren Einfluss auf den gelösten Sauerstoff, die gelösten Nährstoffe und das Phytoplankton zu untersuchen. Selbst während der längsten Schichtungsereignisse (Hitzewellen 2003 und 2006) unterschieden sich die Auswirkungen auf den See von denen, welche in flachen dimiktischen Seen während der kontinuierlichen Sommerschichtung auftreten. Die hypolimnische Temperatur war höher, was die Sauerstoffzehrung und die Akkumulation von gelösten Nährstoffen begünstigt hat. Die thermische Schichtung wird in Zukunft sehr wahrscheinlich zunehmen. Dies lässt darauf schließen, dass polymiktische Seen sehr anfällig gegenüber Änderungen im Hinblick auf projizierte Klimaveränderungen sein werden. Abschließend wurde eine Studie über Lang- und Kurzzeitveränderungen in der Entwicklung der planktischen Larven der Muschel Dreissena polymorpha durchgeführt, um den Einfluss der Veränderungen im thermischen und trophischen Regime des Sees zu analysieren. Die Klimaerwärmung und die Verringerung in der externen Nährstofffracht haben die Abundanz der Larven stark beeinflusst indem sie jeweils auf bestimmte Entwicklungsphasen dieser Art während der warmen Jahreszeiten gewirkt haben. Der Anstieg in der Abundanz und der Länge der Larven stand im Zusammenhang mit dem Rückgang der Nährstofffracht und der Veränderung der Phytoplanktonzusammensetzung. Die Hitzewellen in den Jahren 2003 und 2006 haben diesen positiven Effekt auf die Larvenabundanz jedoch durch ungünstige Sauerstoffkonzentrationen während der sehr langen Schichtung aufgehoben. Die Klimaerwärmung kann demzufolge entgegenwirkende Effekte in produktiven flachen Seen, in welchen die externe Nährstofffracht reduziert wurde, auslösen. Aus diesen Ergebnissen schließe ich, dass nicht nur die Art des Klimawandels und damit der Zeitpunkt der Erwärmung und das Auftreten von Extremen wie Hitzewellen, sondern auch standortspezifische Bedingungen wie Schichtungsverhalten und Trophiegrad entscheidende Faktoren sind, welche die Auswirkungen der Klimaerwärmung auf interne Seeprozesse im Sommer bestimmen. Somit sollte sich die weiterführende Klimafolgenforschung für Seen darauf konzentrieren, wie verschiedene Seetypen auf die komplexen Umweltveränderungen im Sommer reagieren, damit ein umfassenderes Verständnis über den Einfluss von anthropogen verursachten Veränderungen auf Seen der gemäßigten Breiten erreicht wird.
N2  - There is already strong evidence that temperate lakes have been highly vulnerable to human induced climate warming during the last century. Hitherto climate impact studies have mainly focussed on the impacts of the recent long-term warming in winter and spring and little is known on the influence of climate warming on temperate lakes in summer. In the present thesis, I studied some aspects, which may have been strongly involved in determining the response of a lake to climate warming in summer. Thereby I have focussed on climate induced impacts on the thermal characteristics and the phenology and abundance of summer plankton in a shallow polymictic lake (Müggelsee, Germany). First, the influence of climate warming on the phenology and abundance of the lake plankton was investigated across seasons. Fast-growing spring phytoplankton and zooplankton (Daphnia) advanced largely synchronously, whereas long-term changes in the phenology of slow-growing summer zooplankton were clearly species-specific and not synchronised. The phenology and/or abundance of several summer copepod species changed according to their individual thermal requirements at decisive developmental stages such as emergence from diapause in spring. The study emphasises that not only the degree of warming, but also its timing within the annual cycle is of great ecological importance. To analyse the impact of climate change on the thermal characteristics of the lake, I examined the long-term development of the daily epilimnetic temperature extrema during summer. The study demonstrated for the first time for lakes that the daily epilimnetic minima (during nighttime) have increased more rapidly than the daily epilimnetic maxima (during daytime), resulting in a distinct decrease in the daily epilimnetic temperature range. This day-night asymmetry in epilimnetic temperature was likely caused by an increased nighttime emission of long-wave radiation from the atmosphere. This underlines that not only increases in air temperature, but also changes in other meteorological variables such as wind speed, relative humidity and cloud cover may play an important role in determining the lake temperature with respect to further climate change. Furthermore, a short-term analysis on the mixing regime of the polymictic lake was conducted to examine the frequency and duration of stratification events and their impacts on dissolved oxygen, dissolved nutrients and summer phytoplankton. Even during the longest stratification events (heatwaves in 2003 and 2006) the thermal characteristics of the lake differed from those typically found in shallow dimictic lakes, which exhibit a continuous stratification during summer. Particularly, hypolimnetic temperatures were higher, favouring the depletion of oxygen and the accumulation of dissolved nutrient in the hypolimnion. Thermal stratification will be very likely amplified in the future, thus, I conclude that polymictic lakes will be very vulnerable to alterations in the thermal regime with respect to projections of further climate change during summer. Finally, a long-term case study on the long and short-term changes in the development of the planktonic larvae of the freshwater mussel Dreissena polymorpha was performed to analyse the impacts of simultaneous changes in the thermal and in the trophic regime of the lake. Both the climate warming and the decrease in external nutrient load were important in determining the abundance of the pelagic larvae by affecting different features of the life-history of this species throughout the warm season. The long-term increase in the abundance and length of larvae was related to the decrease in external nutrient loading and the change in phytoplankton composition. However, the recent heatwaves in 2003 and 2006 have offset this positive effect on larval abundance, due to unfavourable low oxygen concentrations that had resulted from extremely long stratification events, mimicking the effects of nutrient enrichment. Climate warming may thus induce counteracting effects in productive shallow lakes that underwent lake restoration through a decrease in external nutrient loading. I conclude that not only the nature of climate change and thus the timing of climate warming throughout the seasons and the occurrence of climatic extremes as heatwaves, but also site-specific lake conditions as the thermal mixing regime and the trophic state are crucial factors governing the impacts of climate warming on internal lake processes during summer. Consequently, further climate impact research on lake functioning should focus on how the different lake types respond to the complex environmental forcing in summer, to allow for a comprehensive understanding of human induced environmental changes in lakes.
KW  - Klimawandel
KW  - Gewässerökologie
KW  - Seen
KW  - Climate change
KW  - freshwater ecology
KW  - lakes
Y1  - 2007
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-14599
ER  - 
TY  - JOUR
A1  - Wiesmeier, Martin
A1  - Prietzel, Jörg
A1  - Barthold, Frauke Katrin
A1  - Spörlein, Peter
A1  - Geuss, Uwe
A1  - Hangen, Edzard
A1  - Reischl, Arthur
A1  - Schilling, Bernd
A1  - von Lützow, Margit
A1  - Kögel-Knabner, Ingrid
T1  - Storage and drivers of organic carbon in forest soils of southeast Germany (Bavaria) - Implications for carbon sequestration
JF  - Forest ecology and management
N2  - Temperate forest soils of central Europe are regarded as important pools for soil organic carbon (SOC) and thought to have a high potential for carbon (C) sequestration. However, comprehensive data on total SOC storage, particularly under different forest types, and its drivers is limited. In this study, we analyzed a forest data set of 596 completely sampled soil profiles down to the parent material or to a depth of 1 m within Bavaria in southeast Germany in order to determine representative SOC stocks under different forest types in central Europe and the impact of different environmental parameters. We calculated a total median SOC stock of 9.8 kg m(-2) which is considerably lower compared with many other inventories within central Europe that used modelled instead of measured soil properties. Statistical analyses revealed climate as controlling parameter for the storage of SOC with increasing stocks in cool, humid mountainous regions and a strong decrease in areas with higher temperatures. No significant differences of total SOC storage were found between broadleaf, coniferous and mixed forests. However, coniferous forests stored around 35% of total SOC in the labile organic layer that is prone to human disturbance, forest fires and rising temperatures. In contrast, mixed and broadleaf forests stored the major part of SOC in the mineral soil. Moreover, these two forest types showed unchanged or even slightly increased mineral SOC stocks with higher temperatures, whereas SOC stocks in mineral soils under coniferous forest were distinctly lower. We conclude that mixed and broadleaf forests are more advantageous for C sequestration than coniferous forests. An intensified incorporation of broadleaf species in extent coniferous forests of Bavaria would prevent substantial SOC losses as a result of rising temperatures in the course of climate change.
KW  - Tree species effect
KW  - Soil organic matter
KW  - Climate change
KW  - Forest management
Y1  - 2013
U6  - https://doi.org/10.1016/j.foreco.2013.01.025
SN  - 0378-1127
VL  - 295
IS  - 10
SP  - 162
EP  - 172
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - INPR
A1  - Wellstein, Camilla
A1  - Schröder-Esselbach, Boris
A1  - Reineking, Bjoern
A1  - Zimmermann, Niklaus E.
T1  - Understanding species and community response to environmental change - A functional trait perspective
T2  - Agriculture, ecosystems & environment : an international journal for scientific research on the relationship of agriculture and food production to the biosphere
KW  - Functional traits
KW  - Functional diversity
KW  - Database
KW  - Land use
KW  - Management
KW  - Climate change
KW  - Landscape
KW  - Ecosystem function
KW  - Clonal plants
KW  - Dispersal
KW  - Plant growth
KW  - Orthoptera
Y1  - 2011
U6  - https://doi.org/10.1016/j.agee.2011.06.024
SN  - 0167-8809
VL  - 145
IS  - 1
SP  - 1
EP  - 4
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Vormoor, Klaus Josef
A1  - Lawrence, Deborah
A1  - Schlichting, Lena
A1  - Wilson, Donna
A1  - Wong, Wai Kwok
T1  - Evidence for changes in the magnitude and frequency of observed rainfall vs. snowmelt driven floods in Norway
JF  - Journal of hydrology
N2  - There is increasing evidence for recent changes in the intensity and frequency of heavy precipitation and in the number of days with snow cover in many parts of Norway. The question arises as to whether these changes are also discernable with respect to their impacts on the magnitude and frequency of flooding and on the processes producing high flows. In this study, we tested up to 211 catchments for trends in peak flow discharge series by applying the Mann-Kendall test and Poisson regression for three different time periods (1962-2012, 1972-2012, 1982-2012). Field-significance was tested using a bootstrap approach. Over threshold discharge events were classified into rainfall vs. snowmelt dominated floods, based on a simple water balance approach utilizing a nationwide 1 x 1 km(2) gridded data set with daily observed rainfall and simulated snowmelt data. Results suggest that trends in flood frequency are more pronounced than trends in flood magnitude and are more spatially consistent with observed changes in the hydrometeorological drivers. Increasing flood frequencies in southern and western Norway are mainly due to positive trends in the frequency of rainfall dominated events, while decreasing flood frequencies in northern Norway are mainly the result of negative trends in the frequency of snowmelt dominated floods. Negative trends in flood magnitude are found more often than positive trends, and the regional patterns of significant trends reflect differences in the flood generating processes (FGPs). The results illustrate the benefit of distinguishing FGPs rather than simply applying seasonal analyses. The results further suggest that rainfall has generally gained an increasing importance for the generation of floods in Norway, while the role of snowmelt has been decreasing and the timing of snowmelt dominated floods has become earlier. (C) 2016 Elsevier B.V. All rights reserved.
KW  - Peak flow trends
KW  - Peak-over-threshold
KW  - Flood generating processes
KW  - Rainfall floods
KW  - Snowmelt floods
KW  - Climate change
Y1  - 2016
U6  - https://doi.org/10.1016/j.jhydrol.2016.03.066
SN  - 0022-1694
SN  - 1879-2707
VL  - 538
SP  - 33
EP  - 48
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - GEN
A1  - Vogel, Johannes
A1  - Paton, Eva
A1  - Aich, Valentin
A1  - Bronstert, Axel
T1  - Increasing compound warm spells and droughts in the Mediterranean Basin
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - The co-occurrence of warm spells and droughts can lead to detrimental socio-economic and ecological impacts, largely surpassing the impacts of either warm spells or droughts alone. We quantify changes in the number of compound warm spells and droughts from 1979 to 2018 in the Mediterranean Basin using the ERA5 data set. We analyse two types of compound events: 1) warm season compound events, which are extreme in absolute terms in the warm season from May to October and 2) year-round deseasonalised compound events, which are extreme in relative terms respective to the time of the year. The number of compound events increases significantly and especially warm spells are increasing strongly – with an annual growth rates of 3.9 (3.5) % for warm season (deseasonalised) compound events and 4.6 (4.4) % for warm spells –, whereas for droughts the change is more ambiguous depending on the applied definition. Therefore, the rise in the number of compound events is primarily driven by temperature changes and not the lack of precipitation. The months July and August show the highest increases in warm season compound events, whereas the highest increases of deseasonalised compound events occur in spring and early summer. This increase in deseasonalised compound events can potentially have a significant impact on the functioning of Mediterranean ecosystems as this is the peak phase of ecosystem productivity and a vital phenophase.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1127 
KW  - Compound events
KW  - Warm spells
KW  - Droughts
KW  - Mediterranean basin
KW  - Extreme events
KW  - Climate change
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-496294
SN  - 1866-8372
IS  - 1127
ER  - 
TY  - JOUR
A1  - Vogel, Johannes
A1  - Paton, Eva
A1  - Aich, Valentin
A1  - Bronstert, Axel
T1  - Increasing compound warm spells and droughts in the Mediterranean Basin
JF  - Weather and climate extremes
N2  - The co-occurrence of warm spells and droughts can lead to detrimental socio-economic and ecological impacts, largely surpassing the impacts of either warm spells or droughts alone. We quantify changes in the number of compound warm spells and droughts from 1979 to 2018 in the Mediterranean Basin using the ERA5 data set. We analyse two types of compound events: 1) warm season compound events, which are extreme in absolute terms in the warm season from May to October and 2) year-round deseasonalised compound events, which are extreme in relative terms respective to the time of the year. The number of compound events increases significantly and especially warm spells are increasing strongly – with an annual growth rates of 3.9 (3.5) % for warm season (deseasonalised) compound events and 4.6 (4.4) % for warm spells –, whereas for droughts the change is more ambiguous depending on the applied definition. Therefore, the rise in the number of compound events is primarily driven by temperature changes and not the lack of precipitation. The months July and August show the highest increases in warm season compound events, whereas the highest increases of deseasonalised compound events occur in spring and early summer. This increase in deseasonalised compound events can potentially have a significant impact on the functioning of Mediterranean ecosystems as this is the peak phase of ecosystem productivity and a vital phenophase.
KW  - Compound events
KW  - Warm spells
KW  - Droughts
KW  - Mediterranean basin
KW  - Extreme events
KW  - Climate change
Y1  - 2021
U6  - https://doi.org/10.1016/j.wace.2021.100312
SN  - 2212-0947
VL  - 32
PB  - Elsevier
CY  - Amsterdam
ER  -