Warmer climates have increased the frequency and volume of forest fires across Russia, even in areas which have snow cover. About 98% of forest fires in populated Russia were estimated to be caused by human activity and in more remote areas, approximately 50% caused by thunderstorms and lightening. The researchers reviewed the risks and effect of forest fires in the Volga Federal District in European Russia. It covers about 6% of the Russian Federation and is densely populated.
The largest share of fires caused by lightning in the total number of fires occurs in the latitude interval 60–65° N, which is about 39%. At higher latitudes, it decreases along with a significant weakening of thunderstorm activity. At the latitudes 65–70° N, the proportion of fires caused by lightning in relation to the total number of fires is about 21%
Perevedentsev et al., 2022
The Volga region ranges from approximately 50-62ºN latitudes. The environments vary with dark coniferous forest cover, some deciduous forest in more northern areas then meadow and desert steppes in the southern areas.
They used data from Rosstat (Russia’s Statistics Office) and Meteo (Russia’s Meteorological Office). They found the risk of forest fires was greater with less snow cover, less rainfall, low humidity and generally higher average daily air temperatures. The fires usually ignite in the spring once the snow cover disappears in the northern areas.
They used the Nesterov index to assess the fire hazard for the region which is calculated using data about recent and current precipitation and daily air temperatures. They reviewed climate data from 183 meteorological stations between 1966 and 2018.
They noticed that the air temperature increased between 0.23º and 0.53ºC over 10 years, with the highest rate of warming in January matched by an increase in humidity. Using a flammability index, they found extreme flammability increases from north to south. Overall, there were about 2683 forest fires annually. In 2010 there was a higher air temperature, drought caused by anticyclone activity.

There are regional fluctuations both in meteorological data as well as actual fire incidence. In July it is most dangerous in the southern areas. They noticed a decrease in volume of thunderstorms during the warm period which suggests anthropological causes. They recommend greater environmental and fire protection measures to reduce the risk.
Perevedentsev Y, Sherstyukov B, Gusarov A, Aukhadeev T, Mirsaeva N. Climate-Induced Fire Hazard in Forests in the Volga Federal District of European Russia during 1992–2020. Climate. 2022; 10(7):110. https://doi.org/10.3390/cli10070110