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- ItemUsing Meta-Analysis and GIS for Value Transfer and Scaling Up: Valuing Climate Change Induced Losses of European Wetlands(Dordrecht : Springer, 2012) Brander, L.M.; Bräuer, I.; Gerdes, H.; Ghermandi, A.; Kuik, O.; Markandya, A.; Navrud, S.; Nunes, P.A.L.D.; Schaafsma, M.; Vos, H.; Wagtendonk, A.There is growing policy and academic interest in transferring ecosystem service values from existing valuation studies to other ecosystem sites at a large geographic scale. Despite the evident policy demand for this combined transfer and "scaling up" of values, an approach to value transfer that addresses the challenges inherent in assessing ecosystem changes at a national or regional level is not available. This paper proposes a methodology for scaling up ecosystem service values to estimate the welfare effects of ecosystem change at this larger geographical scale. The methodology is illustrated by applying it to value the impact of climate change on European wetlands for the period 2000-2050. The proposed methodology makes use of meta-analysis to produce a value function. The parameters of the value function include spatial variables on wetland size and abundance, GDP per capita, and population. A geographic information system is used to construct a database of wetland sites in the case study region with information on these spatial variables. Site-specific ecosystem service values are subsequently estimated using the meta-analytic value function. The proposed method is shown to enable the adjustment of transferred values to reflect variation in important spatial variables and to account for changes in the stock of ecosystems.
- ItemSaltwater intrusion under climate change in North-Western Germany - mapping, modelling and management approaches in the projects TOPSOIL and go-CAM(Les Ulis : EDP Sciences, 2018) Wiederhold, Helga; Scheer, Wolfgang; Kirsch, Reinhard; Azizur Rahman, M.; Ronczka, Mathias; Szymkiewicz, Adam; Sadurski, A.; Jaworska-Szulc, B.Climate change will result in rising sea level and, at least for the North Sea region, in rising groundwater table. This leads to a new balance at the fresh–saline groundwater boundary and a new distribution of saltwater intrusions with strong regional differentiations. These effects are investigated in several research projects funded by the European Union and the German Federal Ministry of Education and Research (BMBF). Objectives and some results from the projects TOPSOIL and go-CAM are presented in this poster.
- ItemAre we using the right fuel to drive hydrological models? A climate impact study in the Upper Blue Nile(Göttingen : Copernicus GmbH, 2018) Liersch, S.; Tecklenburg, J.; Rust, H.; Dobler, A.; Fischer, M.; Kruschke, T.; Koch, H.; Hattermann, F.F.Climate simulations are the fuel to drive hydrological models that are used to assess the impacts of climate change and variability on hydrological parameters, such as river discharges, soil moisture, and evapotranspiration. Unlike with cars, where we know which fuel the engine requires, we never know in advance what unexpected side effects might be caused by the fuel we feed our models with. Sometimes we increase the fuel's octane number (bias correction) to achieve better performance and find out that the model behaves differently but not always as was expected or desired. This study investigates the impacts of projected climate change on the hydrology of the Upper Blue Nile catchment using two model ensembles consisting of five global CMIP5 Earth system models and 10 regional climate models (CORDEX Africa). WATCH forcing data were used to calibrate an eco-hydrological model and to bias-correct both model ensembles using slightly differing approaches. On the one hand it was found that the bias correction methods considerably improved the performance of average rainfall characteristics in the reference period (1970-1999) in most of the cases. This also holds true for non-extreme discharge conditions between Q20 and Q80. On the other hand, bias-corrected simulations tend to overemphasize magnitudes of projected change signals and extremes. A general weakness of both uncorrected and bias-corrected simulations is the rather poor representation of high and low flows and their extremes, which were often deteriorated by bias correction. This inaccuracy is a crucial deficiency for regional impact studies dealing with water management issues and it is therefore important to analyse model performance and characteristics and the effect of bias correction, and eventually to exclude some climate models from the ensemble. However, the multi-model means of all ensembles project increasing average annual discharges in the Upper Blue Nile catchment and a shift in seasonal patterns, with decreasing discharges in June and July and increasing discharges from August to November.
- ItemIncreasing risks of apple tree frost damage under climate change(Dordrecht [u.a.] : Springer Science + Business Media B.V, 2019) Pfleiderer, Peter; Menke, Inga; Schleussner, Carl-FriedrichAnthropogenic climate change is affecting agriculture and crop production. The responses of horticultural and agricultural systems to changing climatic conditions can be non-linear and at times counter-intuitive. Depending on the characteristics of the system, the actual impact can arise as a result of a combination of climate hazards or compound events. Here, we show that compound events can lead to increased risk of frost damage for apple fruit trees in Germany in a 2 °C warmer world of up to 10% relative to present day. Although the absolute number of frost days is declining, warmer winters also lead to earlier blossom of fruit trees, which in turn can lead to regionally dependent increased risks of the occurrence of frost days after apple blossom. In southern Germany, warmer winters may also lead to an increase in years in which apple yield is negatively affected by a lack of sufficient amount of cold days to trigger the seasonal response of the trees. Our results show how cropping system responses to seasonal climate can lead to unexpected effects of increased risk of frost damage as a result of warmer winters. An improved understanding of ecosystem responses to changes in climate signals is important to fully assess the impacts of climate change. © 2019, The Author(s).
- ItemAnpassung an den Klimawandel - Potenziale sozialwissenschaftlicher Forschung in Deutschland(München : Oekom - Gesellschaft fuer Oekologische Kommunikation mbH, 2011) Grothmann, T.; Daschkeit, A.; Felgentreff, C.; Görg, C.; Horstmann, B.; Scholz, I.; Tekken, V.[No abstract available]
- ItemGround-penetrating radar insight into a coastal aquifer: the freshwater lens of Borkum Island(Munich : EGU, 2013) Igel, J.; Günther, T.; Kuntzer, M.Freshwater lenses, as important resource for drinking water, are sensitive to climate changes and sea level rise. To simulate this impact on the groundwater systems, hydraulic subsurface models have to be designed. Geophysical techniques can provide information for generating realistic models. The aim of our work is to show how ground-penetrating radar (GPR) investigations can contribute to such hydrological simulations. In the pilot area, Borkum island, GPR was used to map the shape of the groundwater table (GWT) and to characterise the aquifer. In total, 20 km of constant offset (CO) profiles were measured with centre frequencies of 80 and 200 MHz. Wave velocities were determined by common midpoint (CMP) measurements and vertical radar profiling (VRP) in a monitoring well. The 80 MHz CO data show a clear reflection at the groundwater table, whereas the reflection is weaker for the 200 MHz data. After correcting the GPR water tables for the capillary rise, they are in good accordance with the pressure heads of the observation wells in the area. In the centre of the island, the groundwater table is found up to 3.5 m above sea level, however it is lower towards the coastline and marshland. Some local depressions are observed in the region of dune valleys and around pumping stations of the local water supplier. GPR also reveals details within the sediments and highly-permeable aeolian sands can be distinguished from less-permeable marine sediments. Further, a silt loam layer below the water table could be mapped on a large area. The reflection characteristics indicates scattered erosion channels in this layer that cause it to be an aquitard with some leakage. GPR provides a high resolution map of the groundwater table and insight into the stratigraphy of the sediments and their hydraulic properties. This is valuable complementary information to the observation of sparsely distributed monitoring wells as input to hydraulic simulation.
- ItemPredictability of twentieth century sea-level rise from past data(Bristol : IOP Publishing, 2013) Bittermann, Klaus; Rahmstorf, Stefan; Perrette, Mahé; Vermeer, MartinThe prediction of global sea-level rise is one of the major challenges of climate science. While process-based models are still being improved to capture the complexity of the processes involved, semi-empirical models, exploiting the observed connection between global-mean sea level and global temperature and calibrated with data, have been developed as a complementary approach. Here we investigate whether twentieth century sea-level rise could have been predicted with such models given a knowledge of twentieth century global temperature increase. We find that either proxy or early tide gauge data do not hold enough information to constrain the model parameters well. However, in combination, the use of proxy and tide gauge sea-level data up to 1900 AD allows a good prediction of twentieth century sea-level rise, despite this rise being well outside the rates experienced in previous centuries during the calibration period of the model. The 90% confidence range for the linear twentieth century rise predicted by the semi-empirical model is 13–30 cm, whereas the observed interval (using two tide gauge data sets) is 14–26 cm.
- ItemICDP workshop on scientific drilling of Nam Co on the Tibetan Plateau: 1 million years of paleoenvironmental history, geomicrobiology, tectonics and paleomagnetism derived from sediments of a high-altitude lake(Sapporo : IODP, 2019) Haberzettl, Torsten; Daut, Gerhard; Schulze, Nora; Spiess, Volkhard; Wang, Junbo; Zhu, LipingThe Tibetan Plateau is of peculiar societal relevance as it provides freshwater from the so-called “Water Tower of Asia” to a large portion of the Asian population. However, future climate change will affect the hydrological cycle in this area. To define parameters for future climate change scenarios it is necessary to improve the knowledge about thresholds, timing, pace and intensity of past climatic changes and associated environmental impacts. Sedimentary archives reaching far back in time and spanning several glacial–interglacial cycles such as Nam Co provide the unique possibility to extract such information. In order to explore the scientific opportunities that an ICDP drilling effort at Nam Co would provide, 40 scientists from 13 countries representing various scientific disciplines met in Beijing from 22 to 24 May 2018. Besides paleoclimatic investigations, opportunities for paleomagnetic, deep biosphere, tectonic and paleobiological studies were discussed. After having explored the technical and logistical challenges and the scientific opportunities all participants agreed on the great value and need to drill this extraordinary archive, which has a sediment thickness of more than 1 km, likely covering more than 1 Ma.
- ItemImpacts of Climate Change on Riverine Ecosystems: Alterations of Ecologically Relevant Flow Dynamics in the Danube River and Its Major Tributaries(Basel : MDPI AG, 2016) Stagl, J.C.; Hattermann, F.F.
- ItemClimate-driven or human-induced: Indicating severe water scarcity in the Moulouya river basin (Morocco)(Basel : MDPI AG, 2012) Tekken, V.; Kropp, J.P.Many agriculture-based economies are increasingly under stress from climate change and socio-economic pressures. The excessive exploitation of natural resources still represents the standard procedure to achieve socio-economic development. In the area of the Moulouya river basin, Morocco, natural water availability represents a key resource for all economic activities. Agriculture represents the most important sector, and frequently occurring water deficits are aggravated by climate change. On the basis of historical trends taken from CRU TS 2.1, this paper analyses the impact of climate change on the per capita water availability under inclusion of population trends. The Climatic Water Balance (CWB) shows a significant decrease for the winter period, causing adverse effects for the main agricultural season. Further, moisture losses due to increasing evapotranspiration rates indicate problems for the annual water budget and groundwater recharge. The per capita blue water availability falls below a minimum threshold of 500 m3 per year, denoting a high regional vulnerability to increasing water scarcity assuming a no-response scenario. Regional development focusing on the water-intense sectors of agriculture and tourism appears to be at risk. Institutional capacities and policies need to address the problem, and the prompt implementation of innovative water production and efficiency measures is recommended.