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arXiv · 2206.06999

Siberian wildfires and related gas and aerosol emissions into the atmosphere over the past decades

Abstract

Siberian wildfires and related regional anomalies of atmospheric impurities during the period of 2000-2019 are analyzed. The long-range transport of biomass burning products from Siberian wildfires into the Arctic atmosphere during the period of 2000-2019 is estimated. An analysis of the characteristics of forest fires over the past two decades revealed a significant increase in radiation power of an average Siberian wildfire. A joint analysis of fire activity in Siberian forests, as well as the contents of the black carbon (BC) and carbon monoxide (CO) contents in the Arctic atmosphere, indicates that extreme fire events cause the development of regional anomalies in BC and CO. Correlation between the anomalies of BC (CO) over the Russian segment of the Arctic and the number of Siberian wildfires is found to be statistically significant. Using a linear regression, an estimates of the sensitivity of the total BC content and in the volume mixing ratio of CO to the increase in the number of fires. The results of an analysis of the long-range BC transport into the Arctic It is shown, in particular, that the transport of BC to the Arctic from the Siberian regions with fires in the summer of 2019 was associated with the features of large-scale atmospheric circulation characteristic for atmospheric blocking.

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Igor I. Mokhov, Sergei A. Sitnov. 2022-06-14. Siberian wildfires and related gas and aerosol emissions into the atmosphere over the past decades. https://arxiv.org/abs/2206.06999

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