Chemistry Contribution to Stratospheric Ozone Depletion After the Unprecedented Water‐Rich Hunga Tonga Eruption

• Published in: Geophysical Research Letters
• Main Authors: Jun Zhang, Douglas Kinnison, Yunqian Zhu, Xinyue Wang, Simone Tilmes, Kimberlee Dube, William Randel
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2024
• Subjects: stratospheric ozone depletion; volcanic eruption; Geophysics. Cosmic physics; QC801-809; Antarc*; Antarctica
• Online Access: https://doi.org/10.1029/2023GL105762; https://doaj.org/article/07204014e1b940fc9d01e6e8e78aa086

Abstract Following the Hunga Tonga–Hunga Ha'apai (HTHH) eruption in January 2022, stratospheric ozone depletion was observed at Southern Hemisphere mid‐latitudes and over Antarctica during the 2022 austral wintertime and springtime, respectively. The eruption injected sulfur dioxide and unprecedented amounts of water vapor into the stratosphere. This work examines the chemistry contribution of the volcanic materials to ozone depletion using chemistry‐climate model simulations with nudged meteorology. Simulated 2022 ozone and nitrogen oxide (NOx = NO + NO2) anomalies show good agreement with satellite observations. We find that chemistry yields up to 4% ozone destruction at mid‐latitudes near ∼70 hPa in August and up to 20% ozone destruction over Antarctica near ∼80 hPa in October. Most of the ozone depletion is attributed to internal variability and dynamical changes forced by the eruption. Both the modeling and observations show a significant NOx reduction associated with the HTHH aerosol plume, indicating enhanced dinitrogen pentoxide hydrolysis on sulfate aerosol.