Differential intensification of dry and wet climatology temperatures over the indian subcontinent: A historical and climate change perspective

Abstract

Studies have explored concurrent hot extremes and dry events across the world, however, the modulation of average temperature regimes during droughts is lacking. This study explores the differential intensification rates in average temperatures in the historical past and projected future for different climatologies (dry, wet, and average) over the Indian subcontinent, and the intensification rates are linked with established atmospheric feedback mechanisms. Thereafter, future differential shifts in temperatures associated with different climatologies were studied under climate change for the 2 °C and 3 °C warming worlds using CMIP6 simulations. Results show that temperature intensification rates are much more pronounced under dry/wet climatology than average climatology. Dry climatology temperatures (Td) exhibit extensive cooling trends in northern India while warming trends are reported in southern India. Wet climatology temperatures (Tw) show extensive warming trends in northern India. Further, analysis of atmospheric moisture and aridity metrics such as vapor pressure deficit (VPD) and relative humidity (RH) show a stronger linkage with temperatures during the dry/wet climatology compared to the long-term average. Multi-model shifts under climate change project cooling and warming Td shifts under 2 °C and 3 °C levels, respectively with greater pronounced temperature shifts in northern regions. The results of this study have implications for water resource management, drought risk reductions, and mitigation of agricultural crop losses.