Authors

Siyuan Wang, National Center for Atmospheric Research
Eric C. Apel, National Center for Atmospheric Research
Rebecca H. Schwantes, National Center for Atmospheric Research
Kelvin H. Bates, Harvard University
Daniel J. Jacob, Harvard University
Emily V. Fischer, Colorado State University - Fort Collins
Rebecca S. Hornbrook, National Center for Atmospheric Research
Alan J. Hills, National Center for Atmospheric Research
Louisa K. Emmons, National Center for Atmospheric Research
Laura L. Pan, National Center for Atmospheric Research
Shawn Honomichl, National Center for Atmospheric Research
Simone Tilmes, National Center for Atmospheric Research
Jean‐François Lamarque, National Center for Atmospheric Research
Mingxi Yang, Plymouth Marine Laboratory
Christa A. Marandino, Helmholtz‐Zentrum für Ozeanforschung Kiel
E. S. Saltzman, University of California, Irvine
Warren J. de Bruyn, Chapman UniversityFollow
Sohiko Kameyama, Hokkaido University
Hiroshi Tanimoto, National Institute for Environmental Studies, Japan
Yuko Omori, National Institute for Environmental Studies, Japan
Samuel R. Hall, National Center for Atmospheric Research
Kirk Ullmann, National Center for Atmospheric Research
Thomas B. Ryerson, National Oceanic and Atmospheric Administration
Chelsea R. Thompson, National Oceanic and Atmospheric Administration
Jeff Peischl, National Oceanic and Atmospheric Administration
Bruce C. Daube, Harvard University
Róisín Commane, Harvard University
Kathryn McKain, National Oceanic and Atmospheric Administration
Colm Sweeney, National Oceanic and Atmospheric Administration
Alexander B. Thames, Pennsylvania State University
David O. Miller, Pennsylvania State University
William H. Brune, Pennsylvania State University
Glenn S. Diskin, National Aeronautics and Space Administration
Joshua P. DiGangi, National Aeronautics and Space Administration
Steven C. Wofsy, Harvard University

Document Type

Article

Publication Date

7-15-2020

Abstract

Acetone is one of the most abundant oxygenated volatile organic compounds (VOCs) in the atmosphere. The oceans impose a strong control on atmospheric acetone, yet the oceanic fluxes of acetone remain poorly constrained. In this work, the global budget of acetone is evaluated using two global models: CAM‐chem and GEOS‐Chem. CAM‐chem uses an online air‐sea exchange framework to calculate the bidirectional oceanic acetone fluxes, which is coupled to a data‐oriented machine‐learning approach. The machine‐learning algorithm is trained using a global suite of seawater acetone measurements. GEOS‐Chem uses a fixed surface seawater concentration of acetone to calculate the oceanic fluxes. Both model simulations are compared to airborne observations from a recent global‐scale, multiseasonal campaign, the NASA Atmospheric Tomography Mission (ATom). We find that both CAM‐chem and GEOS‐Chem capture the measured acetone vertical distributions in the remote atmosphere reasonably well. The combined observational and modeling analysis suggests that (i) the ocean strongly regulates the atmospheric budget of acetone. The tropical and subtropical oceans are mostly a net source of acetone, while the high‐latitude oceans are a net sink. (ii) CMIP6 anthropogenic emission inventory may underestimate acetone and/or its precursors in the Northern Hemisphere. (iii) The MEGAN biogenic emissions model may overestimate acetone and/or its precursors, and/or the biogenic oxidation mechanisms may overestimate the acetone yields. (iv) The models consistently overestimate acetone in the upper troposphere‐lower stratosphere over the Southern Ocean in austral winter. (v) Acetone contributes up to 30–40% of hydroxyl radical production in the tropical upper troposphere/lower stratosphere.

Comments

This article was originally published in Journal of Geophysical Research: Atmospheres, volume 125, in 2020. https://doi.org/10.1029/2020JD032553

Copyright

American Geophysical Union

Available for download on Friday, January 15, 2021

Share

COinS