Impact of Tropospheric Chemistry on Atmospheric Composition and Climate in Northern Russia

The study presents the results of investigating the impact of tropospheric chemistry on atmospheric composition and the climate of Northern Russia using the Russian Earth System Model ARTs-ESM [Volodin, 2023; Smyshlyaev et al., 2024]. Atmospheric composition strongly influences radiative balance and atmospheric circulation, while also being influenced by climatic conditions that control the intensity of chemical reactions and the transport of trace species. Therefore, atmospheric composition and the climate system are closely interconnected and should be considered a single coupled system.

Within this study, tropospheric chemistry was implemented in the Earth system model, expanding its capability to investigate interactions between atmospheric composition, radiative processes, and atmospheric dynamics. Numerical experiments were conducted both with and without tropospheric chemistry, as well as with the inclusion of chemistry–radiation–dynamics feedback.

The results demonstrate that the inclusion of tropospheric chemistry leads to substantial changes in the distributions of ozone (O₃), carbon monoxide (CO), hydroxyl radicals (OH), and nitrogen dioxide (NO₂). The largest changes are found in tropical and mid-latitude regions, where ozone formation is controlled by photochemical processes involving volatile organic compounds and nitrogen oxides. The inclusion of chemistry–radiation–dynamics feedback further enhances the impact of tropospheric chemistry on atmospheric composition through modifications to radiative heating, atmospheric circulation, and the vertical transport of chemical species.

Particular attention is given to Northern Russia. The inclusion of tropospheric chemistry alters the spatial distribution of ozone both near the surface and in the lower stratosphere. In addition, the atmospheric temperature response in high latitudes was analyzed.

The results highlight the importance of jointly accounting for tropospheric chemistry, radiative processes, and atmospheric dynamics in climate modeling and climate change assessments, particularly in high-latitude regions, including Northern Russia.

This work was supported by the Russian Science Foundation No. 23-77-30008.