TR2Ex Measurements of the Hunga Tonga-Hunga Ha'apai Eruption Plume

P.J. Walter¹, S.L. Alvarez², J. Flynn², S. Evan³, J. Brioude^4,5, J. Metzger⁶, A. Baron^3,5, G. Payen⁷, V. Duflot³, E.C. Asher^4,8, M.A. Todt^4,5, K.H. Rosenlof⁵, T. Thornberry⁵ and R. Gao⁵

¹St. Edward's University, Austin, TX 78704; 512-637-5636, E-mail: pauljw@stedwards.edu
²University of Houston, Department of Earth and Atmospheric Sciences, Houston, TX 77004
³Laboratoire de l’Atmosphère et Cyclones LACy, UMR8105, Université de La Réunion, 97744 Saint-Denis Cedex 09, France
⁴Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado, Boulder, CO 80309
⁵NOAA Chemical Sciences Laboratory (CSL), Boulder, CO 80305
⁶Observatoire des Sciences de l’Univers OSU-Réunion / UMS3365, Université de La Réunion, CNRS, France
⁷UAR 3365 – OSU Réunion, Université de La Réunion, Saint-Denis, Réunion, France
⁸NOAA Global Monitoring Laboratory (GML), Boulder, CO 80305

The 15 January 2022 Hunga Tonga-Hunga Haˈapai (HTHH) eruption led to the Tonga volcano Rapid Response Experiment (TR2Ex) deployment to the Maïdo Observatory in La Réunion (21°S, 55°E). From 21 to 25 January 2022, a suite of balloon-borne in situ stratospheric measurements included sulfur dioxide (SO2), aerosol, ozone, and water vapor complemented by remote sensing observations from ground-based lidar. Four balloon soundings measuring SO2 passed through the HTHH eruption plume at altitudes ranging from 19 to 30 km. The balloon-based in situ SO2 measurements of the HTHH volcanic plume were the first of their kind for a stratospheric volcanic eruption. The first two soundings on 21-22 January occurred in a dense water vapor-rich part of the HTHH plume and had lower SO2 to aerosol extinction ratios than the last two profiles on 24-25 January. Profiles on 21-22 January showed ozone depletion in the HTHH plume, with less than 10% of the observed decrease in ozone signal due to SO2 interference.

References

[1] Yoon, S., Kotsakis, A., Alvarez, S. L., Spychala, M. G., Klovenski, E., Walter, P., Morris, G., Corrales, E., Alan, A., Diaz, J. A., and Flynn, J. H. (2022). Development and testing of a novel sulfur dioxide sonde. Atmospheric Measurement Techniques, 15(14), 4373-4384. https://doi.org/10.5194/amt-15-4373-2022 

Acknowledgements

Funding for the SO2 sonde deployment to La Réunion was provided by SilverLining. We thank Maïdo Observatory in La Réunion for hosting members of the Tonga volcano Rapid Response Experiment (TR2Ex).