Fire episodes and air quality over India from January to June.

Fires not only affect the lives and scenic beauty but also cause climate change, impair air quality, and health problems in the region. Fire-related incidents have risen sharply in the past few years all over the globe. We attempted to find out the dominant reasons for the fire episodes and their impact on air quality in India using 3 years of fire count data from NASA VIIRS and AOD-550 and CO from Sentinel-5P's Tropospheric Monitoring Instrument (TROPOMI) over India from January to June during 2019-21. Total fire counts showed a "valley(V)" shape over India during 2019-2021. The contributions of the forest followed a similar "V" shape pattern with 52.6% (2019), 45.7% (2020), and 61.6% (2021) respectively, whereas, agriculture residual burning showed a completely opposite pattern with 44.45% (2019), 51.3% (2020), and 36.5% (2021) respectively. We have also computed the regional contribution to the total fire counts in India. The agricultural residual fire has dominated in Indo Gangetic Plain (IGP) and Western region, whereas, the forest fire contributed more in the Northern, Eastern, Central, and Southern Parts of India. Among all the regions, the highest fire count was observed in the central region and least in the Northern. In the central India region, forest fire dominated during 2019 (61%) and 2021(67%), but in 2020, agricultural residual burning reported a higher which is about 47% of the total fire count during the same year. The mean concentration of pollutants (CO and AOD) was the highest in Central India as compared to other regions, from March to May. In central India, the concentration of pollutants is also higher during 2019 and 2021 as compared to 2020. Due to COVID-19, the lockdown was imposed from March-May in 2020 over the whole of India. This lockdown reduced the human interaction with the ecosystem and resources and could be the possible reason for the lower forest fire count during 2020. Here we find that humans' interaction with the ecosystem could be more responsible for forest fire as well as agricultural residual burning than natural calamities.