Future water stress scenario in South Asia under the Paris Agreement

Anthropogenic forcing is projected to severely impact the water security of South Asia, particularly under current water policies, socio-economic paradigms, and population trends. In this study, we present the first assessment of Water Scarcity (WS) in SA under the Paris Agreement, using two global hydrological models (GHM) forced by three global climate models (GCM) under RCP 6.0. Our results reveal that a significant change in the hydrological fluxes is reducing water availability, along with an intense increase in water consumption. We also found that the seasonal shifting in water scarcity will increase the population affected by approximately 16% from June to September and up to 42% from December to February. We identified spatial hotspots of water scarcity in South Asia, including North-central, Northwestern, and Southern India, Eastern Pakistan, and Northern and Northwestern Bangladesh. Our observations show that a 1.5 ºC temperature increase is crucial for WS in SA and will have a profound impact on 875 million people. We suggest that the Paris Agreement’s temperature target of even 1.5 ºC will not alleviate future warming-driven WS. Therefore, immediate mitigations and legislation are needed to curtail the impact of the changing climate on water scarcity. This is especially important in the hotspots identified in this study.