Disclaimer: This material is being kept online for historical purposes. Though accurate at the time of publication, it is no longer being updated. The page may contain broken links or outdated information, and parts may not function in current web browsers. Visit https://espo.nasa.gov for information about our current projects.


Analysis and Impact of the Hunga Tonga-Hunga Ha'apai Stratospheric Water Vapor...

Schoeberl, M. R., Y. Wang, R. Ueyama, G. Taha, E. Jensen, and W. Yu (2023), Analysis and Impact of the Hunga Tonga-Hunga Ha'apai Stratospheric Water Vapor Plume, Geophys. Res. Lett..

On 15 January 2022, the Hunga Tonga-Hunga Ha'apai eruption injected SO2 and H2O into the middle stratosphere. The eruption produced a persistent mid-stratospheric sulfate aerosol and H2O layer mostly confined to Southern Hemisphere (SH) tropics (Eq. to 30°S). These layers are still present in the tropics 5½ months after the eruption. The SH tropical confinement is simulated using a trajectory model. Measurements following the eruption show that the H2O layer is slowly rising while the aerosol layer is descending. The H2O layer's upward movement is consistent with the residual vertical velocity. Gravitationally settling explains the descent of the aerosol layer. A −4 K temperature anomaly coincident with the H2O enhancement is observed and is caused by thermal adjustment to the additional H2O IR cooling. A simple model of volcanic water injection at the time of the eruption simulates the observed vertical distribution H2O. Plain Language Summary The Hunga Tonga-Hunga Ha'apai submarine volcanic eruption on 15 January 2022, injected up to 150 Tg of water into the stratosphere. A month after eruption, a distinct aerosol and water vapor layer formed in the tropical southern hemisphere (SH) stratosphere. The water vapor layer is slightly displaced above the aerosol layer at 26 km. These two layers continued to persist in the tropical SH stratosphere until the end of June while slowly moving apart in altitude. The isolation of the layers and their separate motion are consistent with our understanding of tropical stratospheric dynamics. A cold temperature anomaly forms coincident with the water vapor layer, which we show to be due to enhanced IR radiative cooling by water vapor. Using a simple model, we show how the water vapor layer forms slightly above the aerosol layer.

Research Program: 
Atmospheric Composition
Atmospheric Composition Modeling and Analysis Program (ACMAP)
Upper Atmosphere Research Program (UARP)