Asian Summer Monsoon Anticyclone—The Primary Entryway for Chlorinated Very‐Short‐Lived Substances to the Stratosphere
Abstract Rapid growing emissions of dichloromethane (CH 2 Cl 2 ), a chlorinated very‐short‐lived substance (Cl‐VSLS) and an ozone depleting substance (ODS), has raised concerns as this increase offset a part of the stratospheric chlorine (Cl) reduction due to decreasing long‐lived ODSs. We have combined simulations of the two most abundant Cl‐VSLSs, CH 2 Cl 2 and chloroform (CHCl 3 ) using the NASA GEOS Chemistry Climate Model (GEOSCCM) with Asian Summer Monsoon Chemical and CLimate Impact Project aircraft observations to examine transport of Cl‐VSLSs to the stratosphere and to assess their contribution to total stratospheric Cl. With ongoing large emissions (total ∼1,500 Gg yr −1 ), Cl‐VSLSs add about 100 ppt Cl to the stratosphere between 2020 and 2022. The Asian Summer Monsoon plays a primary role in the troposphere‐to‐stratosphere transport of Cl‐VSLSs and delivers double the amount to the stratosphere, about 200 ppt Cl in August 2022. The overall Cl‐VSLSs impact on stratospheric chlorine (∼3.3%) and ozone (∼1 DU) remain small.
Authors
- R. Hendershot
- Leslie R. Lait (ORCID: https://orcid.org/0000-0002-8363-859X)
- S. Schauffler (ORCID: https://orcid.org/0000-0002-4516-3378)
- Luke M. Western (ORCID: https://orcid.org/0000-0002-0043-711X)
- Victoria Treadaway (ORCID: https://orcid.org/0000-0003-0564-3702)
- Paul A. Newman (ORCID: https://orcid.org/0000-0003-1139-2508)
- E. Atlas (ORCID: https://orcid.org/0000-0003-3847-5346)
- Katie Smith (ORCID: https://orcid.org/0000-0002-4656-064X)
- Laura L. Pan (ORCID: https://orcid.org/0000-0001-7377-2114)
- Douglas Edward Kinnison (ORCID: https://orcid.org/0000-0002-3418-0834)
- Eric L. Fleming (ORCID: https://orcid.org/0000-0003-0880-0232)
- Qing Liang (ORCID: https://orcid.org/0000-0002-8430-0515)
- Stephen Donnelly (ORCID: https://orcid.org/0009-0004-7793-8264)
- Richard Lueb
Institutions
- NSF National Center for Atmospheric Research (US)
- Goddard Space Flight Center (US)
- University of Miami (US)
- University of Bristol (GB)
- NOAA Chemical Sciences Laboratory (US)
- Science Systems and Applications (United States) (US)
- Fort Hays State University (US)
Publication Details
- Journal
- Geophysical Research Letters
- Published
- 2025-02-04
- DOI
- https://doi.org/10.1029/2024gl110248
- Citations
- 2
- Primary Topic
- Atmospheric Ozone and Climate
- Type
- article
- Field-Weighted Citation Impact
- 2.60
Funders
- National Science Foundation
- National Aeronautics and Space Administration