Vulnerability assessment of rainfed agriculture to climate change in semi-arid tropics

Abstract

Three decades ago, semi-arid tropical farmers relied on predictable monsoon patterns that no longer hold. This research assessed the vulnerability of rainfed agriculture to climate change across five semi-arid districts in peninsular India using an integrated indicator framework based on exposure, sensitivity, and adaptive capacity. Climate projections under RCP 4.5 and RCP 8.5 for the 2030s and 2050s were derived from CMIP5 model ensembles. Household surveys (n = 640), district-level secondary data, and remote-sensing-based vegetation indices were combined to construct a composite vulnerability index for each district. Results showed that Anantapur district scored the highest overall vulnerability (0.78) due to high exposure to temperature rise and low adaptive capacity. Under RCP 8.5 by the 2050s, mean temperature is projected to increase by 2.61°C and monsoon rainfall to decline by 23.1%, which would reduce rainfed sorghum yields by an estimated 31-38%. The findings point to urgent need for crop diversification, drought-tolerant varieties, and supplemental micro-irrigation in the most vulnerable districts.