Estimation of Aerosol Optical Depth Using MODIS Satellite Data and Its Relation with Particulate Matter Concentration in The Mining Regions

Abstract

Airborne contaminants occur in the gaseous form or as aerosols. They may exist in the form of airborne dust, sprays, mists, smokes and fumes. According to occupational health study, all these forms may be important because they relate to a wide range of occupational health diseases. The atmosphere in the mines is always associated with dust, fumes and different gasses. Compare to underground coal mines, dust generation at opencast mines is too high. These days to fulfill the demand rate, there is an increasing in the number of opencast coal mines. Those release an enormous amount of dust. Drilling, blasting, loading and unloading, coal handling and transportation are the common sources of air pollution in mines. These air pollutants degraded the air quality, and they have an adverse impact on the health of people, animals and agriculture. Ground-based monitoring of particulate matter has been restricted to few selective sites. To overcome the problem, the present study utilised the Aerosol Optical Depth (AOD) level measured from satellite data to estimate the PM2.5 concentration over different coal mines. Aerosol Optical Depth is the measure of aerosols distributed over the column of air from the earth surface to the atmosphere. The present study analyses Moderate Resolution Imaging Spectroradiometer (MODIS) data to estimate AOD levels. MODIS on board Terra and Aqua satellites are viewing the entire Earth's surface every 1 to 2 days. So that annual, seasonal and diurnal variation of AOD level can be studied. Seasonal/monthly AOD variation were estimated for the year 2014-2015 over the coal mining regions of Odisha state. Diurnal AOD variations were studied during three months (April-June, 2014). The AOD levels were extracted from the AOD maps and used for regression analysis (both simple and multiple) for prediction of particulate matter (PM2.5) dust concentrations.