An update on the perturbations in stratospheric composition and climate following the Hunga Tonga-Hunga Ha'apai volcanic eruption

The Hunga Tonga-Hunga Ha'apai (HTHH) volcanic eruption on January 15th 2022 injected unprecedented amounts of H₂O as well as modest amounts of aerosol precursor sulfur dioxide into the stratosphere. Satellite observations have shown strong stratospheric cooling and circulation changes throughout 2022. Large ozone reduction in the Southern Hemisphere wintertime midlatitudes and springtime Antarctic ozone losses are also observed. In addition, a chemistry-climate model (WACCM) can track the evolving HTHH plumes and capture observed responses to the volcanic eruption till the end of 2023. We will present a comprehensive update regarding the perturbations in stratospheric composition and their effects on large-scale circulation since the HTHH eruption. We will also examine the longer-term evolution of HTHH H₂O burden and will quantify the contributions of polar dehydration, stratosphere-troposphere exchange of mass, and chemical process.