Representing rainfall extremes over the Indo-Gangetic Plains using CORDEX-CORE simulations

The Indo-Gangetic Plain (IGP), which is the site of India's Green Revolution, covers almost 15% of the country's landmass and is among the most extensively fertile lands across the world. The densely populated IGP region bears great importance for the socioeconomic facets of India and contributes to a major share of the GDP of the country. The present study demonstrates the regional-specific assessment of summer monsoon precipitation and associated extremes with dynamical and thermodynamical aspects over the IGP region using high-resolution regional climate models (RCMs) under the CORDEX-CORE framework. The analysis reveals that the eastern parts of the IGP receive low-to-moderate precipitation with a higher tail than the western parts, which is due to the direction of the monsoon low-level flow. The observed mean precipitation characteristics are well represented by the RCMs. Further, the research identifies extreme precipitation events over the IGP and conducts comprehensive analysis to understand their underlying mechanisms. It has been observed that extreme precipitation events are linked with the moisture transport associated with trough activity and instability, and RCMs are capable in representing the observed precipitation extremes and underlying mechanisms at localized scales. Overall, this study represents a significant step forward in understanding the evolution of spatio-temporal variability of precipitation over the IGP region, where agriculture is a major economic activity and millions of people depend on rainfed agriculture.