Impact of climate change on sorghum productivity in India and its adaptation strategies

Future climate change projections for India indicate distinct rise in temperature and increased variability in rainfall. This study aims to assess the impact of climate change on sorghum productivity in India in future climatic periods (2025, 2050 and 2075) using DSSAT-sorghum and suggest adaptation strategies to negate the negative impact of climate change on sorghum productivity in the future climates. Three CMIP-5 climate models (GFDL-ESM2M, MIROC5 and NorESM1-M) generated weather data for three future periods were used at various locations for kharif (Akola, Dharwad, Surat and Udaipur) and rabi (Bijapur, Dharwad, Rahuri and Solapur) seasons to simulate sorghum yields. Projected changes in day-night temperatures and rainfall during kharif and rabi growing seasons at these locations are diverse both in direction and magnitude. Increasing trend in rainfall is observed during both crop seasons towards the end of 21st century. Sorghum crop is likely to experience warmer temperature in the second half of the century and rise in minimum temperature is more explicit than maximum temperature at all the locations. Location specific management options can be adopted to mitigate the negative impacts of the change in climate in future projected scenarios, as they are found beneficial.

Trends in water requirements of wheat crop under projected climates in India

Various global circulation models predict a change in net irrigation requirements worldwide due to the impacts of climate change and in India, depending upon the region, irrigation requirements are likely to change by different magnitudes. The spatial distribution of trend in crop and irrigation water requirements of wheat projected for two climatic periods (2021-50 and 2051-80) across major wheat growing districts of the country were analyzed, making use of climate change projection data from  NorESM1-M model of the CMIP5 in combination with RCP 4.5. Decreasing trends in water requirements were projected over 90 per cent of wheat growing districts in 2021-50, whereas increasing trends in crop and irrigation water requirement are expected over 95.4 per cent and 62.4 per cent areas, respectively in 2051-80 climatic periods. Results showed that decreasing/increasing trends projected in water requirements of wheat crop is due to change in crop growing period, which is projected to decrease across entire wheat growing area in 2021-50, whereas it is likely to increase over 78.2 per cent in 2051-80 climatic periods