Satelite Observations of AOD during Wide Spread Forest Fires over Uttarakhand State of India

Abstract:

The diurnal and monthly AOD has been analysed during forest fires (April -June, 2016) from the recent Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm (MCD19A2), a combined product of MODIS level-2 collection version 6.0 gridded data at 1 km pixel resolution over Uttarkhand region, India. Significantly high AOD values of 3.2 are observed during the month of April 2016, while for the successive next two months, the AOD of 2.0 and 1.2 are found over the fire burning regions during May and June months, respectively. The effect of these forest fires can be seen over the neighboring country Nepal as well as North-eastern Indian states as the wind direction during fires is mostly from west to east. The air quality is found to be under 'severely affected' category as per NAAQS air quality standards over western and eastern parts of Uttarakhand. The Normalised Burn Ratio Thermal (NBRT) from LandSat-8 shows much higher ratios during April and May 2016. The comparative analysis of NBRT of 2016 with respect to 2015 and 2017 shows a positive difference towards the western side of Uttarakhand. This depicts the dominance of fire over the western region in Uttarakhand, India. The maximum extinction of particles was limited to the 2 km (altitude), while the elevated smoke reaching at altitude of 4 to 5 km have also been observed.