TY - JOUR
T1 - Global water availability under high-end climate change: A vulnerability based assessment
AU - Koutroulis, A. G.
AU - Papadimitriou, L. V.
AU - Grillakis, M. G.
AU - Tsanis, I. K.
AU - Warren, Rachel
AU - Betts, R. A.
PY - 2019/4
Y1 - 2019/4
N2 - Global sustainability is intertwined with freshwater security. Emerging changes in global freshwater availability have been recently detected as a combined result of human interventions, natural variability and climate change. Expected future socioeconomic and climatic changes will further impact freshwater resources. The quantification of the impacts is challenging due to the complexity of interdependencies between physical and socioeconomic systems. This study demonstrates a vulnerability based assessment of global freshwater availability through a conceptual framework, considering transient hydro-climatic impacts of crossing specific warming levels (1.5 °C, 2 °C and 4 °C) and related socioeconomic developments under high-end climate change (RCP8.5). We use high resolution climate scenarios and a global land surface model to develop indicators of exposure for 25,000 watersheds. We also exploit spatially explicit datasets to describe a range of adaptation options through sensitivity and adaptive capacity indicators according to the Shared Socioeconomic Pathways (SSPs). The combined dynamics of climate and socioeconomic changes suggest that although there is important potential for adaptation to reduce freshwater vulnerability, climate change risks cannot be totally and uniformly eliminated. In many regions, socioeconomic developments will have greater impact on water availability compared to climate induced changes. The number of people under increased freshwater vulnerability varies substantially depending the level of global warming and the degree of socioeconomic developments, from almost 1 billion people at 4 °C and SSP5 to almost 3 billion people at 4 °C and SSP3. Generally, it is concluded that larger adaptation efforts are required to address the risks associated with higher levels of warming of 4 °C compared to the lower levels of 1.5 °C or 2 °C. The watershed scale and country level aggregated results of this study can provide a valuable resource for decision makers to plan for climate change adaptation and mitigation actions.
AB - Global sustainability is intertwined with freshwater security. Emerging changes in global freshwater availability have been recently detected as a combined result of human interventions, natural variability and climate change. Expected future socioeconomic and climatic changes will further impact freshwater resources. The quantification of the impacts is challenging due to the complexity of interdependencies between physical and socioeconomic systems. This study demonstrates a vulnerability based assessment of global freshwater availability through a conceptual framework, considering transient hydro-climatic impacts of crossing specific warming levels (1.5 °C, 2 °C and 4 °C) and related socioeconomic developments under high-end climate change (RCP8.5). We use high resolution climate scenarios and a global land surface model to develop indicators of exposure for 25,000 watersheds. We also exploit spatially explicit datasets to describe a range of adaptation options through sensitivity and adaptive capacity indicators according to the Shared Socioeconomic Pathways (SSPs). The combined dynamics of climate and socioeconomic changes suggest that although there is important potential for adaptation to reduce freshwater vulnerability, climate change risks cannot be totally and uniformly eliminated. In many regions, socioeconomic developments will have greater impact on water availability compared to climate induced changes. The number of people under increased freshwater vulnerability varies substantially depending the level of global warming and the degree of socioeconomic developments, from almost 1 billion people at 4 °C and SSP5 to almost 3 billion people at 4 °C and SSP3. Generally, it is concluded that larger adaptation efforts are required to address the risks associated with higher levels of warming of 4 °C compared to the lower levels of 1.5 °C or 2 °C. The watershed scale and country level aggregated results of this study can provide a valuable resource for decision makers to plan for climate change adaptation and mitigation actions.
U2 - 10.1016/j.gloplacha.2019.01.013
DO - 10.1016/j.gloplacha.2019.01.013
M3 - Article
VL - 175
SP - 52
EP - 63
JO - Global and Planetary Change
JF - Global and Planetary Change
SN - 0921-8181
ER -
