LAUSR

Abstract Climate change has been a challenge for the planners, who aim to make sustainable policies regarding staple food security and economic sustainability of smallholder farmers. There is a dire need for a conformed policy framework that quantizes monetary losses caused by the climate change on crops and suggests response policies under realistic climatic projections. The present study develops a climate change response policy framework for Ganges river basin by projecting climatic scenarios (temperature, rainfall, potential evapotranspiration) under intergovernmental panel on climate change representative concentration pathway (RCP) 2.6 for carbon dioxide emission. The study uses a Geographical Information System (GIS) based spatiotemporal-trend approach and evaluates economic loss using Agricultural Production Systems sIMulator (APSIM) crop simulation for the Ganges river basin. The policies have been derived by using fuzzy entropy decision making method. The novelty of the study is that it evaluates impact of climate change on crop yield under multiple scenarios expectations i.e. optimistic, neutral, and pessimistic. A case study of Ganges basin, India is taken and various indices (CSI- Climate Sustainability Index and CRS- Climate Risk Security) has been introduced that can be used by the planners to implement sustainable climatic response policies. Results show that winter crops (Rabi season) in the Ganges river basin are most vulnerable to future climate change risks as the basin is expected to be heated more in winter season as compared to summer. The expected reduction in seasonal rainfall is likely to nullify any carbon fertilization benefits on winter crop yields. Crop field in south-west Ganges basin (i.e. Chambal, Betwa, Ken and Son catchments) came out to be the most vulnerable. Based on the results, sustainable crop insurance policy has been suggested.