[A-CG35] Projection and detection of global environmental change

[ACG35-P06] Climate impact of reducing CO2 and other emissions from the COVID-19 pandemic

*Rumi Ohgaito¹, Manabu Abe¹, Tomohiro Hajima¹, Kaoru Tachiiri¹, Michio Kawamiya¹ (1.Japan Agency for Marine-Earth Science and Technology)

Keywords:COVID-19, greenhouse gas, earth system model

The COVID-19 pandemic had a significant impact on human life around the world, especially in the spring of 2020, when many countries imposed lockdowns and other restrictions. As a result, anthropogenic greenhouse gas emissions, including CO2, and anthropogenic aerosol emissions fell to unprecedented levels (Le Quere et al. 2020, Liu et al. 2020), with an estimated reduction of about 7% in one year in 2020 (Friedlingstein et al. 2020). A previous study (Forster et al. 2020), which used a simple climate model to estimate the impact of this emissions reduction on global warming, estimated that the direct impact of the emissions reduction in the two years 2020 and 2021 would be negligible and would have little effect on the pace of global warming. However, as the model only calculates global values, it is unable to capture regional changes and their mechanisms. Therefore, the model comparison project CovidMIP (Jones et al. 2021) was launched to simulate the same settings as in the previous study, based on the scenario-MIP SSP2-4.5 of CMIP6, and the Earth system model MIROC-ES2L was also involved. An initial analysis of the results of ensemble simulations using MIROC-ES2L shows that a two-year decrease in emissions results in a decrease in the optical thickness of the Asian region, but there is no significant change in annual mean temperature or precipitation. We will continue with the analysis in shorter timescale and present the results including the multi-model analysis in CovidMIP.