Tsunamis from volcanic ‘explosive’ eruptions are rare, with the last catastrophic event being Krakatau in 1883 (Verbeek, 1885), during which, tsunamis were generated in the far-field by pressure shock-waves and in the nearfield of the volcano, in the Sunda Straits, by several potential geological mechanisms including pyroclastic flows, ash column, and/or caldera collapse. On 1/22/55, at about 4:15 UTC, a one in 1,000 year eruption of the Hunga Tonga-Hunga Ha’a-pai Volcano (HTHHV), that had started on12/20/21, reached its paroxysm with a series of large underwater explosions, releasing enormous energy (4-18 Mt of TNT), and ejecting a large ash plume 58 km into the stratosphere. We simulate both the near- and far-field tsunami generation from the eruption, but in this paper we focus on analyzing and validating the near-field impact against field data.
The eruption of the Hunga Tonga–Hunga Ha’apai volcano on 15 January 2022 offered a good opportunity to explore the early impacts of tropical volcanic eruptions on stratospheric composition. Balloon-borne observations near Réunion Island revealed the unprecedented amount of water vapor injected by the volcano. The enhanced stratospheric humidity, radiative cooling, and expanded aerosol surface area in the volcanic plume created the ideal conditions for swift ozone depletion of 5% in the tropical stratosphere in just 1 week. The decrease in hydrogen chloride by 0.4 parts per million by volume (ppbv) and the increase in chlorine monoxide by 0.4 ppbv provided compelling evidence for chlorine activation within the volcanic plume. This study enhances our understanding of the effect of this unusual volcanic eruption on stratospheric chemistry and provides insights into possible chemistry changes that may occur in a changing climate.
more » « less- Award ID(s):
- 2027252
- PAR ID:
- 10546606
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- American Association for the Advancement of Science (AAAS)
- Date Published:
- Journal Name:
- Science
- Volume:
- 382
- Issue:
- 6668
- ISSN:
- 0036-8075
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The Hunga Tonga‐Hunga Ha'apai (HTHH) volcanic eruption in January 2022 injected unprecedented amounts of water vapor (H2O) and a moderate amount of the aerosol precursor sulfur dioxide (SO2) into the Southern Hemisphere (SH) tropical stratosphere. The H2O and aerosol perturbations have persisted during 2022 and early 2023 and dispersed throughout the atmosphere. Observations show large‐scale SH stratospheric cooling, equatorward shift of the Antarctic polar vortex and slowing of the Brewer‐Dobson circulation. Satellite observations show substantial ozone reductions over SH winter midlatitudes that coincide with the largest circulation anomalies. Chemistry‐climate model simulations forced by realistic HTHH inputs of H2O and SO2qualitatively reproduce the observed evolution of the H2O and aerosol plumes over the first year, and the model exhibits stratospheric cooling, circulation changes and ozone effects similar to observed behavior. The agreement demonstrates that the observed stratospheric changes are caused by the HTHH volcanic influences.
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Abstract On 15 January 2022, Hunga volcano erupted, creating an extensive and high-reaching umbrella cloud over the open ocean, hindering traditional isopach mapping and fallout volume estimation. In MODIS satellite imagery, ocean surface water was discolored around Hunga following the eruption, which we attribute to ash fallout from the umbrella cloud. By relating intensity of ocean discoloration to fall deposit thicknesses in the Kingdom of Tonga, we develop a methodology for estimating airfall volume over the open ocean. Ash thickness measurements from 41 locations are used to fit a linear relationship between ash thickness and ocean reflectance. This produces a minimum airfall volume estimate of
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