Rainfall and Temperature Projections and their Impact Assessment Using CMIP5 Models under Different RCP Scenarios for The Eastern Coastal Region of India

Abstract

Trend analysis of annual rainfall over the coastal districts of Odisha, India showed statistically nonsignificant increasing trend in all districts, except Ganjam. Whereas the maximum and minimum temperature showed significant increasing trend. Warming in these districts is mainly due to increasing minimum temperature during summer and rainy season, and maximum temperature during winter. Future climate projection results revealed, the annual mean rainfall is expected to change by 0.1-2.2%, -0.3-0.7% and 1.5-3.2% (RCP 4.5), and 3.6-7.9%, 3.7-6.6% and 8.5-14% (RCP 8.5) during the near (2011-39), mid (2040-69) and late (2070-99) centuries respectively. Anticipate climate change will have a marginal impact on total rainfall, and a major impact on its distribution. The annual mean minimum temperature is expected to increase by 0.60-0.73C, 0.71-0.88C, 1.20-1.42C (RCP 4.5), and 1.77-2.14C, 1.56-1.68C, 3.06-3.73C (RCP 8.5) during near, mid and late centuries respectively. Similarly, the annual mean maximum temperature is expected to increase by 0.61-0.66C, 0.68-0.72C and 1.35-1.55C (RCP 4.5), and 1.79-1.97C, 1.73-2.01C and 3.08-3.44C (RCP 8.5) during near, mid and late centuries respectively. Season-wise projection revealed that the change in rainfall and temperature is expected to be more in winter and summer under both the RCP scenarios. The projected future climate change will have both positive and negative impacts on agriculture. The negative impacts are expected to be more pronounced during kharif in comparison to rabi.