Investigating the impact of compound extremes on crop yield response of cotton: A case study

Abstract

Abstract Agricultural productivity is significantly affected by weather and climate extremes such as droughts and heat waves. Despite several studies addressing the impact of individual and compound extremes on crop yields, there needs to be more comprehensive understanding of their duration thresholds beyond which the crop declines significantly. Hence, in this study, an analysis was carried out to understand the duration thresholds of the compound and individual extremes under varying scenarios for cotton. Future yields were simulated using the bias-corrected projections from 8 climate models and DSSAT-CROPGRO-Cotton crop simulation model. Future yields are predicted for three different scenarios i) rainfed with constant [CO2] (S1), ii) rainfed with elevated [CO2] (S2) and iii) full irrigation with elevated [CO2] (S3). The results reveal that the overall cotton yields in the study area are likely to decrease by the end of the century under all scenarios (SSP585 > SSP370 > SSP245). The duration threshold (change point) increases from S1 to S3, i.e., S1 < S2 < S3. Due to Coincidental Heatwaves and Droughts and Heatwaves alone in the SSP585 scenario, a decline in the crop yield of about 33%, 23%, and 15% is observed in the S1, S2, and S3 scenarios, respectively.