Deep Diving the Recent Dust Storm Events (2018-2022) in India

Dust storms represent significant meteorological phenomena in India, particularly impacting the arid and semi-arid regions. This study examines five major dust storm events (DSEs) that occurred between 2018 and 2022 across Mumbai, Ahmedabad, and Delhi, providing a comprehensive analysis of associated environmental and atmospheric parameters. We utilized meteorological datasets from the European Centre for Medium-Range Weather Forecasts (ECMWF) fifth-generation ERA5 reanalysis products, aerosol data from satellite instruments including the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Ozone Monitoring Instrument (OMI), along with ground-based observations of PM2.(5) and PM10. The results show that the 850 hPa steering flow, combined with low tropospheric relative humidity (RH) and reduced surface solar radiation (SSR), played a crucial role in DSE formation. During these events, SSR remained relatively higher in Mumbai and Ahmedabad, while Delhi experienced a significant decline due to dense dust loading. These atmospheric conditions were associated with increased Aerosol Optical Depth (AOD) and reduced & Aring;ngstr & ouml;m Exponent (AE), indicating the predominance of coarse-mode aerosols. Elevated PM2.(5) and PM10 levels, particularly over Delhi, reached peak values of 363 and 952 mu g/m(3), respectively. Vertical aerosol profiles from Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) revealed dense dust layers extending up to 5 km altitude, with high depolarization ratios (DPRs) confirming the presence of non-spherical mineral dust particles, especially over Delhi. Five-day back trajectories from the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model indicated dust transport from the Arabian Peninsula, Thar Desert, Pakistan, and Central Asia, with additional inputs from the Bay of Bengal and local anthropogenic sources.