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 - 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 - 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 - 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 - 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 -