Assessment of Post-Fire Forest Loss in Siberia Using Satellite Data and Its Relationship with Characteristics of Fires

Abstract

Here, the effect of the energy characteristics of fires, their seasonality, and duration on the number of fires causing the death of forest stands in Siberia in 2002–2022 was studied. The energy characteristics of fires were assessed using an indicator, such as the fire radiative power (FRP), measured using data from the MODIS radiometer. To assess the degree of disturbance of forest stands and to identify those fires that led to the death of the forest stand, a product of changes in global forest cover, generated from Landsat satellite data, was used. Over the period from 2002 to 2022, the region experienced an increase in both the total burned area and the area of fires resulting in the death of the forest stand. At the same time, an increase in the recorded fire radiative power was observed. The total values of the fire radiative power released during the duration of the fire in the case of fires that caused the death of forest stands (390.2 (σ = 80.5) MW/km²) turned out to be significantly higher (p < 0.01) than the values of fire radiative power for fires that did not lead to the death of forest stands (291.8 (σ = 74.7) MW/km²). The fire radiative power in dark coniferous forests and larch forests was on average 20–25% higher than that for fires in mixed forests dominated by deciduous stands. Fires that were accompanied by the death of forests were commonly recorded in the second half of summer, with a maximum occurring from July to the first decade of August, while fires that did not lead to the death of the forest stand were observed throughout the entire fire season. Moreover, stand-replacement fires were characterized by a longer duration (average duration, 4.8 (σ = 1.0) days) compared to non-stand-replacement fires (3.9 (σ = 0.7) days).