MODELING THE IMPACT OF A SUPERVOLCANIC ERUPTION ON THE CLIMATE SYSTEM UNDER PRESENT AND FUTURE CONDITIONS

Powerful volcanic eruptions are among the most significant natural factors global affecting Earth's climate system, capable of causing substantial changes in temperature, atmospheric circulation, and air chemical composition.

This study presents a powerful volcanic eruption (similar to the Tambora eruption in 1815) impact on the climate system under various background conditions. We performed a series of experiments with the chemistry–climate model SOCOL-MPIOM for three time periods: present conditions and two future climate scenarios: SSP3-70 and SSP2-45. The experimental design is based on quasi-random sampling methodology, allowing the optimal exploration of key model parameter space with minimal numerical experiments.

The climatic effect of a powerful volcanic eruption intensifies in the warmer climate of the late 21st century, manifesting in a deeper temperature drop (up to 2.5-3K for SSP2-45) and a longer recovery period, compared to the present period (1-1.5K).

Unlike the temperature response, the ozone layer reaction demonstrates a complex spatial structure with pronounced latitudinal asymmetry: a decrease in ozone content at high latitudes (up to -8 DU) and an increase in tropical latitudes (+4-6 DU). This effect is associated with changes in circulation and the photochemical processes of ozone formation.

The most intense analog of the historical 'year without summer' is observed in the SSP2-45 scenario, which may be related to higher concentrations of methane and NOx in this scenario, affecting photochemical processes in the atmosphere and enhancing the radiative effect of volcanic aerosols.

The recovery timescales of the ozone layer (5-7 years) exceed the period of temperature relaxation (3-4 years), indicating the long-term impact of volcanic forcing on the chemical composition of the atmosphere and highlighting the importance of considering chemical feedback when assessing the climatic consequences of powerful volcanic eruptions. This work was supported by Saint Petersburg State University under research grant 116234986.