edu.ucar.opensky::articles:26512 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-24T19:27:43.790230 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d76m3bvp https://doi.org/10.17632/g3yv4ztvd9.1 https Related Dataset #1 Natural_Halogens_Tropospheric_Ozone_Pre-Industrial_Present-Day Comparing the effect of anthropogenically amplified halogen natural emissions on tropospheric ozone chemistry between pre-industrial and present-day 2023-07-27T00:00:00Z publication https://n2t.org/ark:/85065/d76m3bvp https://doi.org/10.1029/2022JD038283 Barrera, J. A. author Kinnison, Douglas E. author Fernandez, R. P. author Lamarque, Jean-François author Cuevas, C. A. author Tilmes, Simone author Saiz-Lopez, A. author UCAR/NCAR - Library publisher Reactive halogens (X + XO, X = I, Br or Cl) catalytically destroy a fraction of tropospheric ozone under present-day (PD) conditions, however, their distribution and potential impact on tropospheric ozone under pre-industrial (PI) conditions remain largely unexplored. This study uses the Community Atmosphere Model with Chemistry (CAM-Chem) to investigate the effect of anthropogenically amplified natural emissions of halogenated species and their subsequent chemistry on tropospheric ozone under PI and PD atmospheric conditions. Model results show that the global tropospheric ozone depletion due to natural halogens is slightly more sensitive in PI than PD, with percentage changes in tropospheric ozone burden (TOB) of -14.1 +/- 0.6% for PI and -12.9 +/- 0.6% for PD. Individually, the role of iodine and chlorine in ozone depletion is equivalent in both periods (Delta TOBI: similar to-7% and Delta TOBCl: similar to-2.5%), while bromine plays a larger role in PI (Delta TOBBr: -5.5 +/- 0.6%) versus PD (Delta TOBBr: -4.3 +/- 0.7%). The increase in anthropogenic ozone precursor emissions from PI to PD has amplified the natural emission of inorganic halogens and led to a shift in the partitioning of inorganic halogens from reactive to reservoir species. Consequently, halogen-driven ozone depletion from the surface to the free troposphere is larger in PI than PD. In contrast, in the upper troposphere, the ozone depletion is larger in PD influenced mainly by stratospheric intrusion of reactive halogens from long-lived species. This study highlights the importance of including a complete chemical coupling of natural halogens and atmospheric pollutants in chemistry-climate models to adequately assess their effects on tropospheric ozone in a changing climate. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. None eng geoscientificInformation