Role of land surface processes on Indian summer monsoon rainfall: Understanding and impact assessment

Abstract

Indian Summer Monsoon is a synoptic-scale atmospheric circulation system manifested by the boundary forcing from both continents and tropical oceans. Unlike oceans, the land surface processes are complex in nature due to the heterogeneities in land surface characteristics and its associated feedbacks, thereby constraining the accurate representation of the land surface in NWP models. Thus, understanding the land-atmosphere interaction becomes increasingly crucial especially during the Indian summer monsoon season due to the underlying warm and moist surface layer that are highly sensitive to the evapotranspiration, thereby fueling land atmosphere coupling during the season. The representation of surface heterogeneity and variability are constrained due to lack of surface measurements which necessitate development of land surface analysis. The major aim of the present study is three-fold; firstly, understanding land surfaces processes associated with the monsoonal rainfall events, secondly, preparation of a state-of-art high-resolution land surface data over India and finally, impact assessment of high-resolution land surface initialization on simulation monsoonal rainfall events. This study has implications for developing improved prediction system associated with the Indian Summer Monsoon. � 2023, India Meteorological Department. All rights reserved.