Assessing the variability of Aerosol Optical Depth over India in
response to future scenarios: Implications for carbonaceous aerosols
Abstract
Air pollution caused by various anthropogenic activities and biomass
burning continues to be a major problem in India. To assess the
effectiveness of current air pollution mitigation measures, we used a 3D
global chemical transport model to analyze the projected optical depth
of carbonaceous aerosol (AOD) in India under representative
concentration pathways (RCP) 4.5 and 8.5 over the period 2000-2100. Our
results show a decrease in future emissions, leading to a decrease in
modeled AOD under both RCPs after 2030. The RCP4.5 scenario shows a
48-65% decrease in AOD by the end of the century, with the
Indo-Gangetic Plain (IGP) experiencing a maximum change of
~25% by 2030 compared to 2010. Conversely, RCP8.5
showed an increase in AOD of ~29% by 2050 and did not
indicate a significant decrease by the end of the century. Our study
also highlights that it is likely to take three decades for current
policies to be effective for regions heavily polluted by exposure to
carbonaceous aerosols, such as the IGP and eastern India. We emphasize
the importance of assessing the effectiveness of current policies and
highlight the need for continued efforts to address the problem of air
pollution from carbonaceous aerosols, both from anthropogenic sources
and biomass burning, in India.