Atmospheric Rivers Impact on High Asia Mountain Precipitation

Precipitation and resulting warm season glacial melt in High Mountain Asia provides water resources for a large population of people in southern and central Asia. Thus, understanding the impact of Atmospheric Rivers (AR) on these hydrological resources is critical. This research aims to understand the spatio-temporal changes in the relevant hydrological components relating to ARs (i.e. water vapor, wind, precipitation) over a 35 year period using Modern Era Retrospective Reanalysis Version 2 (MERRA2) focusing on Southern Asia. More specifically, this research develops a detailed climatology of ARs in Southern Asia (a region rich with AR activity) and examines the impact of Atmospheric Rivers (ARs) on local precipitation regimes in High Mountain Asia. Recent research has concluded that ARs are responsible for over 50% of the variance in precipitation in extratropical regions (e.g. poleward of 40°N) during winter seasons (Nash et al., 2018). This present study demonstrates that ARs provide a critical link in understanding the underlying dynamical and physical processes that regulate the local precipitation regimes in Southern Asia with great influence in High Mountain Asia.