Impact of anthropogenic activity and cyclonic storm on black carbon during winter at a tropical urban city,Pune

Black carbon (BC) aerosols are emitted into the atmosphere as a byproduct of different combustion processes and are reported to be a very strong absorber of solar radiation. In this paper, we present results on BC aerosols over Pune, a tropical urban city in south west India during Diwali festival in the month of November 2010. Daily mean BC showed about 5 % increase on Diwali day compared with preceding and succeeding period with concentrations reaching as high as about 21 μg/m³ in the morning on Diwali day, mainly due to the influence of extensive fireworks. However, the strong winds accompanied by occasional rainfall due to severe cyclonic storm “Jal” formed in the Bay of Bengal on the same day dampened this effect and reduced BC to about 2 μg/m³ within 6 h. There was only 5 % increase in mean BC concentration on Diwali day during 2010 as compared to the average increase of about 17 % during preceding 4 years on Diwali day, mainly due to the impact of weather conditions induced by Jal.