The impact of January 2022 Hunga Eruptions on Stratospheric Ozone in the NASA GEOS Chemistry Climate Model

The January 2022 eruptions of the underwater Hunga volcano injected about 150 Tg of water vapor and approximately 0.5 Tg of sulfur dioxide into the stratosphere. As a participant of the SPARC/APARC HTHH activity, we have conducted 3-D model simulations to investigate the transport and impact of the erupted materials in coupled aerosol-chemistry simulations with the NASA Goddard Earth Observing System Chemistry Climate Model (GEOSCCM). A sulfur mechanism introduced into the Global Modeling Initiative (GMI) stratospheric-tropospheric chemistry package allows for interactive simulation of the water vapor-chemistry impacts, and the large water vapor perturbation results in rapid conversion of sulfur dioxide to sulfate aerosol in our aerosol mechanism. Two sets of 10-member ensemble simulations are conducted: a controlled ensemble (no eruption) and a water vapor and sulfur dioxide-combined injection ensemble. We use these simulations to investigate the 10-year impact of the volcanic materials, particularly the unprecedented large amount of water injected into the stratosphere, on the stratospheric temperature, circulation, and the ozone layer between 2022-2031.

Our preliminary results suggest that (1) the resulting Hunga impact on stratospheric temperature, ozone, winds, and circulation lasts > 5 years, and (2) the Hunga-induced global and polar ozone changes are small compared to interannual dynamical variability. Further analysis details will be presented.