Sulfate aerosols resulting from large volcanic eruptions contribute as a natural forcing agent in the climate system, and they are currently prescribed in the current version of E3SM. The Five-mode Modal Aerosol Model (MAM5) is a novel feature developed by the E3SM Next Generation Development (NGD) Atmospheric Physics Project to provide interactive treatment of stratospheric aerosols. MAM5, built upon the previous four-mode version of the Modal Aerosol Model (MAM4), introduces a dedicated Stratospheric Coarse Mode to represent stratospheric sulfate aerosols while minimizing the associated computational costs. By integrating MAM5, E3SM achieves improved accuracy in capturing the stratospheric sulfate burden, as demonstrated after the Mt. Pinatubo eruption in June 1991. This advancement in E3SM's aerosol representation enhances its ability to simulate natural climate variability and enables investigations into the field of Geoengineering.
