Stereo Plume Height and Motion Retrievals for the Record-Setting Hunga
Tonga-Hunga Ha'apai Eruption of 15 January 2022
Abstract
Stereo methods using GOES-17 and Himawari-8 applied to the Hunga
Tonga-Hunga Ha’apai volcanic plume on 15 January 2022 show overshooting
tops reaching 50-55 km altitude, a record in the satellite era. Plume
height is important to understand dispersal and transport in the
stratosphere and climate impacts. Stereo methods, using geostationary
satellite pairs, offer the ability to accurately capture the evolution
of plume top morphology quasi-continuously over long periods. Manual
photogrammetry estimates plume height during the most dynamic early
phase of the eruption and a fully automated algorithm retrieves both
plume height and advection every 10 minutes during a more frequently
sampled and stable phase beginning three hours after the eruption.
Stereo heights are confirmed with Global Navigation Satellite System
Radio Occultation (GNSS-RO) bending angles, showing that most of the
plume was lofted 30–40 km into the atmosphere. Cold bubbles are
observed in the stratosphere with brightness temperature of
~173K.