Articles | Volume 21, issue 18
Research article
21 Sep 2021
Research article |  | 21 Sep 2021

Global tropospheric halogen (Cl, Br, I) chemistry and its impact on oxidants

Xuan Wang, Daniel J. Jacob, William Downs, Shuting Zhai, Lei Zhu, Viral Shah, Christopher D. Holmes, Tomás Sherwen, Becky Alexander, Mathew J. Evans, Sebastian D. Eastham, J. Andrew Neuman, Patrick R. Veres, Theodore K. Koenig, Rainer Volkamer, L. Gregory Huey, Thomas J. Bannan, Carl J. Percival, Ben H. Lee, and Joel A. Thornton

Data sets

ATom: L2 Measurements from the NOAA ToF Chemical Ionization Mass Spectrometer (CIMS) P. R. Veres, J. A. Neuman, and T. B. Ryerson

UW-High Resolution Time of Flight Mass Spectrometer -- CIMS1. Version 1.1 UCAR/NCAR - Earth Observing Laboratory

Airborne Multi-AXis Differential Optical Absorption Spectroscopy (AMAX-DOAS) Data R. Volkamer, T. Koenig, S. Baidar, and B. Dix

Georgia Tech Chemical Ionization Mass Spectrometer (GTCIMS) Bromine In Situ Measurements, Version 3.0 L. Huey

GV AMAX-DOAS Data, Version 5.0 R. Volkamer and B. Dix

FAAM B826 CAST flight, number 3: Airborne atmospheric measurements from core and non-core instrument suites on board the BAE-146 aircraft Facility for Airborne Atmospheric Measurements, Natural Environment Research Council, Met Office

Model code and software

geoschem/geos-chem: GEOS-Chem 12.9.0 (12.9.0) B. Yantosca, M. Sulprizio, L. Lundgren, kelvinhb, 22degrees, D. Ridley, S. D. Eastham, R. Pound, T. Sherwen, H. Lin, J. Fisher, W. Downs, C. Thackray, michael-s-long, C. Holmes, GanLuo, J. Zhuang, SpaceMouse, L. Bindle, L. Murray, noelleselin, xin-chen-github, emily-ramnarine, gianga, L. Zhu, F. Yao, C. Fite, S. Song, and zsx-GitHuband ayhwong

Short summary
Halogen radicals have a broad range of implications for tropospheric chemistry, air quality, and climate. We present a new mechanistic description and comprehensive simulation of tropospheric halogens in a global 3-D model and compare the model results with surface and aircraft measurements. We find that halogen chemistry decreases the global tropospheric burden of ozone by 11 %, NOx by 6 %, and OH by 4 %.
Final-revised paper