Advances in global hydrology–crop modelling to support the UN’s Sustainable Development Goals in South Asia

Achieving the United Nation’s Sustainable Development Goals (SDG) in the context of a rapidly changing climate and demographics is one of the major challenges for South Asia. Interventions aimed at achieving the SDGs will be varied and are likely to contain basin-wide trade-offs that need to be understood. In this paper, we synthesize recent global hydrology-crop model developments, with a specific focus on human impact parameterisations like the management of human built storage capacity, irrigation withdrawal and supply, and irrigation efficiency. We show that these models can help improve our understanding of the composition and flows of water, and the linkages between water scarcity and food production. To fully exploit the potential of improved models for policy support and the design of pathways towards SDG achievement, we envisage scope to include more local data from test fields and pilot sites, use the models to derive biophysical and financial feasibility of interventions, and improve the interaction with policy-makers and regional stakeholders through the development of better communication and visualisation tools.