Continuation of Satellite Observations of NO2 over South Asia using Ozone Monitoring Instrument during the time period of 2004-2016

Abstract

NO2 is one often criterion air pollutant considered as an indicator for air quality index. More the concentrations, more the toxic environment for living beings. Different sources impart in NO2 atmospheric concentrations, for instance biofuel consumption, soils emissions, aircrafts and fossil fuels burning. Elevated concentrations of NO2 are fallen in serious category for health risk assessment. South Asia is one of the most affected regions as its economic potential is engrossing interests from all over the world. In this study, TEMIS NO2 data sets were used for the time period of 2004-2016. NO2 from Satellite Observations is retrieved using a DOAS-base algorithm. Spatio temporal analysis and multi-year mean maps clearly depicts different concentrations in different seasons and regions. For instance, relatively large column densities have been reported over hyper arid regions during Monsoon time spans due to augmented bacterial activities in their soils. In addition to it, lightening is also prime source for enhanced atmospheric NO2 levels the emissions. Temporal mean maps have indicated enhanced column densities in India, Pakistan and Bangladesh region. On the contrary, Bhutan and Nepal are contributing relatively in smaller amounts. This propense pertains in Industrial emissions and transport sector. Additionally, recent economic boom in south Asian countries is major driver behind enhanced atmospheric NO2 levels across the region. Key Words: OMI Observations, Emission inventories, Tropospheric NO2, South Asian Pollution, NO2 Seasonal Trends