Columnar optical, microphysical and radiative properties of the 2022 Hunga Tonga volcanic ash plumes

Ke Gui; Huizheng Che; Lin Tian; Yaqiang Wang; Chong Shi; Wenrui Yao; Yuanxin Liang; Lei Li; Yu Zheng; Lei Zhang; Zhaoliang Zeng; Junting Zhong; Zhili Wang; Xiaoye Zhang

doi:10.1016/j.scib.2022.08.018

Columnar optical, microphysical and radiative properties of the 2022 Hunga Tonga volcanic ash plumes

Sci Bull (Beijing). 2022 Oct 15;67(19):2013-2021. doi: 10.1016/j.scib.2022.08.018. Epub 2022 Aug 18.

Authors

Ke Gui¹, Huizheng Che², Lin Tian³, Yaqiang Wang¹, Chong Shi⁴, Wenrui Yao¹, Yuanxin Liang¹, Lei Li¹, Yu Zheng¹, Lei Zhang¹, Zhaoliang Zeng¹, Junting Zhong¹, Zhili Wang¹, Xiaoye Zhang¹

Affiliations

¹ State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of China Meteorological Administration, Chinese Academy of Meteorological Sciences, Beijing 100081, China.
² State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of China Meteorological Administration, Chinese Academy of Meteorological Sciences, Beijing 100081, China. Electronic address: chehz@cma.gov.cn.
³ National Satellite Meteorological Center, China Meteorological Administration, Beijing 100081, China.
⁴ State Key Laboratory of Remote Sensing Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100081, China.

PMID: 36546211
DOI: 10.1016/j.scib.2022.08.018

Abstract

The Hunga Tonga-Hunga Ha'apai eruption on January 15, 2022 was one of the most explosive volcanic eruptions of the 21st century and has attracted global attention. Here we show that large numbers of the volcanic aerosols from the eruption broke through the tropopause into the lower stratosphere, forming an ash plume with an overshooting top at 25-30 km altitude. In the four days following the eruption, the ash plume moved rapidly westward for nearly 10,000 km under stable stratospheric conditions characterized by strong tropical easterlies, weak meridional winds and weak vertical motion. The intrusion of the ash plume into the stratosphere resulted in a marked increase in atmospheric aerosol loading across northern Australia, with the aerosol optical depth (AOD) observed by satellites and sun-photometers peaking at 1.5 off the coast of northeastern Australia; these effects lasted for nearly three days. The ash plume was characterized by fine-mode particles clustered at a radius of about 0.26 µm, with an observed peak volume of 0.25 µm³ µm^-2. The impact of the ash plume associated with the Hunga Tonga eruption on the stratospheric AOD and radiative balance in the tropical southern hemisphere is remarkable, with an observed volcanic-induced perturbation of the regional stratospheric AOD of up to 0.6. This perturbation largely explains an instantaneous bottom (top) of the atmosphere radiative forcing of -105.0 (-65.0) W m^-2 on a regional scale.

Keywords: Aerosol optical–microphysical properties; Hunga Tonga-Hunga Ha’apai eruption; Multi-satellite and ground-based observations; Radiative forcing; Volcanic aerosols.