Researchers at the Institute of Atmospheric Physics have discovered a correlation between atmospheric smoke and the fires that cause it.

For several years, a group of physicists led by Doctor of Physical and Mathematical Sciences, Senior Researcher at the Atmospheric Physics and Microwave Diagnostics Department of the Institute of Applied Physics of the Russian Academy of Sciences, Igor Konovalov, has been studying smoke aerosols generated by forest fires in Siberia and their role in atmospheric processes. In their 2024 study, physicists from Nizhny Novgorod identified for the first time the reverse impact of smoke on fires through atmospheric precipitation.

To achieve this, numerical experiments were conducted using the modeling complex CHIMERE-WRF developed by French colleagues from the École Polytechnique and the University of Paris-Est-Créteil (UPEC). This model allows for the simulation of atmospheric pollution and weather on a regional scale, taking into account the feedback effect of atmospheric aerosol on meteorological conditions.

The physicists analyzed satellite data on precipitation and fire intensity. As a result, the researchers found that in heavily smoke-affected areas of the Siberian taiga, the intensity of precipitation decreases, due to the cooling of the ground surface caused by smoke shading and local weakening of moisture circulation. This leads to the "thinning" of clouds — a reduction in their water content and optical thickness. The suppression of precipitation by smoke increases the emissions from taiga fires by approximately 30 percent. At the same time, over tundra landscapes experiencing less smoke, there is a slight increase in precipitation.

This results in a decrease in emissions from fires in the tundra by about 15 percent. "The effects of smoke on weather conditions and the complex feedbacks in the fire-smoke-weather system are still poorly understood. However, research in this area is very relevant and actively pursued worldwide, with results published in leading scientific journals. Particularly, the impact of Siberian wildfires, which are the primary source of smoke over Northern Eurasia and Eastern Arctic, is not well studied," said Igor Konovalov.

The research conducted by the physicists at the Institute of Applied Physics of the Russian Academy of Sciences demonstrated the connection between wildfires and the occurrence of precipitation. Knowledge in this field can enhance the effectiveness of wildfire suppression, improve early warning systems for the population, and increase the accuracy of climate change forecasts. The project is supported by a grant from the Russian Science Foundation.