Aerosols properties during dust-storm episodes over Jaipur, Northwestern India

摘要

Continuous routine aerosol measurements have been carried out at Jaipur (Rajasthan, Northwestern India) since April 2009 with a CIMEL sun photometer integrated in the global Aerosols Robotic Network (AERONET) program. The present study investigates the aerosol properties during dust storm episodes over Jaipur, Northwestern India. A series of high dust storms were identified as indicated by high values of aerosols optical thickness (AOT) with a significant drop in angstrom exponent values (nearly zero and negative). Consequently, a progressive increase in Single Scattering Albedo (SSA440 nm = 0.89, SSA675 nm = 0.95, SSA870 nm = 0.97, SSA1020 nm = 0.976) suggests more scattering nature of regional aerosols associated with abundant dust loading. Trajectories back in time showed that the air collected in Jaipur during dust period originated from desert regions in the western part of India. Additionally, a comparative analysis of the mean AOT derived from satellite data and Potential Source Contribution Function (PSCF) analysis helped to understand the source region of these particles.