Short-term perturbation in aerosol characteristics over Northwestern India: A case study during Diwali festival

The present study examines the effect of Diwali festival (17-21 October 2017; 19th October was the Diwali day) on aerosol characteristics over Patiala, northwestern part of India. Diwali being one of the major festivals of India that falls between mid-October and mid-November is celebrated with full enthusiasm by burning crackers, fireworks, etc. During this period, the study site also is engulfed with high aerosol loading because of extensive paddy residue burning emission. During Diwali event, a particulate matter (PM10) concentration varies from 132 to 155 mu gm(-3), while a mass concentration of black carbon aerosols varies from 6 to 9 mu gm(-3) with the maximum concentration on post-Diwali day. Aerosol optical depth (AOD(500)) was maximum (0.852) on post-Diwali day indicating the additional loading of submicron particles due to burning of crackers and fireworks. The magnitude of single scattering albedo (SSA(500)) decreases to a minimum value around 0.864 showing abundance of absorbing aerosols on Diwali affected days (19th and 20th October). A sudden jump of +12.9Wm(-2) in atmospheric radiative forcing resulting in a heating rate of up to 1.4Kday(-1) on next day of Diwali shows the warming state of the lower and middle atmosphere.