Stratospheric Aerosols, Polar Stratospheric Clouds, and Polar Ozone Depletion After the Mount Calbuco Eruption in 2015

• Published in: Journal of Geophysical Research: Atmospheres
• Main Authors: Zhu, Yunqian, Toon, Owen Brian, Kinnison, Douglas, Harvey, V. Lynn, Mills, Michael, Bardeen, Charles, Pitts, Michael, Bègue, Nelson, Renard, Jean-Baptiste, Berthet, Gwenaël, Jégou, Fabrice
• Other Authors: Laboratory for Atmospheric and Space Physics Boulder (LASP), University of Colorado Boulder, National Center for Atmospheric Research Boulder (NCAR), NASA Langley Research Center Hampton (LaRC), Laboratoire de l'Atmosphère et des Cyclones (LACy), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Météo France, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales Paris (CNES), ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2018
• Subjects: [SDU]Sciences of the Universe [physics]; Antarctic; The Antarctic; Antarc*
• Online Access: https://hal-insu.archives-ouvertes.fr/insu-01926153; https://hal-insu.archives-ouvertes.fr/insu-01926153/document; https://hal-insu.archives-ouvertes.fr/insu-01926153/file/Zhu_et_al-2018-Journal_of_Geophysical_Research%253A_Atmospheres.pdf; https://doi.org/10.1029/2018JD028974

International audience We investigate the impact of the 2015 Mount Calbuco eruption and previous eruptions on stratospheric aerosols, polar stratospheric clouds, and ozone depletion using the Community Earth System Model coupled with the Community Aerosol and Radiation Model for Atmospheres compared with several satellite and balloon observations. The modeled volcanic sulfate aerosol size distribution agrees with the Light Optical Aerosol Counter observation at the Reunion Island site (21°S, 55°E) on 19 August at 20 km within estimated 0.1-to 1-μm radius error bars. Both the observed and simulated backscatter and extinction show that volcanic sulfate aerosol from the Mount Calbuco eruption was transported from midlatitude toward the Antarctic and slowly descended during transport. They also indicate that the SO 2 emission into the stratosphere from Mount Calbuco is 0.2-0.4 Tg. The modeled number density indicates that the volcanic sulfate aerosol from the Mount Calbuco eruption penetrated into the Antarctic polar vortex in May and thereafter and reduced the polar stratospheric clouds effective radius. In the simulations, the Antarctic stratosphere denitrified too early and by too much compared with Microwave Limb Sounder observations. Heterogeneous nucleation of nitric acid trihydrate or sophisticated gravity wave representations may be required to simulate nitric acid trihydrate particles with smaller falling velocity. The volcanic sulfate aerosol increases the ozone depletion in September especially around 100 hPa and 70°S, relative to a case without any volcanic eruptions. The simulated surface area density, earlier ozone loss, and larger area of the ozone hole are consistent with the presence of volcanic sulfate layers observed at 16 km as well as previous studies.