SATELLITE DATA BASED STUDY ON LONG TERM VARIATION OF BLACK CARBON OVER BENGALURU, KARNATAKA, INDIAK.E. GANESHAbstract Black Carbon (BC) content in the atmosphere is an important parameter which tells us about the contribution of fossil fuel burning in altering cloud structure and monsoon. Total Aerosol Optical Thickness (AOT) data and AOT due to BC at 550nm have been collected along with necessary parameters from NASA's Giovanni website for the period 2010 to 2018 for the continental south Indian location Bengaluru of Karnataka state, India. It has been found that during November-2011 the percentage contribution of AOT-BC towards total AOT at 550 nm is found to be least (0.69%). On the other hand, during February-2017 the percentage contribution of AOT-BC records highest value (11.54%). On annual average scale, the year 2011 records lowest contribution of AOT-BC (5.218%), whereas the year 2016 records the highest contribution of AOT-BC (6.735%) towards total AOT at 550nm. Also it has been observed that there is a small reduction in Incoming short wave solar radiation (ISR) from 2010 (99.63 W/m2) to 2018 (86.73 W/m2) indicating the accumulation of particulates in the atmosphere. However there appears no significant change in the outgoing long wave radiation (OLR) from the year 2010 (226.39 W/m2) to 2018 (230.08 W/m2). The reason for change in BC concentration over year with possible justification is discussed in this paper. |