Modeling the global budget of tropospheric bromine and its impact on atmospheric chemistry
Roozitalab, B., Apel, E. C., Hornbrook, R., Fernandez, R., Gaubert, B., et al. (2025). Modeling the global budget of tropospheric bromine and its impact on atmospheric chemistry.
| Title | Modeling the global budget of tropospheric bromine and its impact on atmospheric chemistry |
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| Genre | Conference Material |
| Author(s) | Behrooz Roozitalab, Eric C. Apel, Rebecca Hornbrook, R. Fernandez, Benjamin Gaubert, Haipeng Lin, Douglas E. Kinnison, C. Cuevas, A. Saiz-Lopez, Louisa K. Emmons |
| Abstract | Bromine, a reactive halogen radical, plays a significant role in ozone depletion upon reaching the upper troposphere and lower stratosphere. Furthermore, it can affect tropospheric chemistry cycles and the atmosphere’s oxidation capacity. The ocean serves as the dominant source of atmospheric brominated species, originating from biological production in seawater followed by emission through sea-to-air transfer processes. Abiotic processes such as sea salt debromination contribute additional bromine to the atmosphere. Using the recently developed short lived halogen (SLH) version of the Community Earth System Modeling framework (CESM2-SLH) and a machine learning model, we developed a global emission inventory for two main short lived brominated compounds (CHBr3 and CH2Br2) with projections to the future under different climate change scenarios. We evaluated the results against our measurements using the NSF National Center for Atmospheric Research Trace Organic Gas Analyzer (NSF NCAR TOGA) during the 2016 NSF O2/N2 Ratio and CO2 Airborne Southern Ocean Study (ORCAS) and the 2016–2018 NASA Atmospheric Tomography (ATom) mission, and measurements made by the NSF NCAR TOGA-TOF (with a time-of-flight mass spectrometer) during the 2022 NSF/NASA Asian summer monsoon Chemical and Climate Impact Project (ACCLIP). For present day conditions, we estimate the global emissions of 269–271 Gg Br and 61–65 Gg Br for CHBr3 and CH2Br2, respectively. We will discuss the results of the sensitivity experiments using the CESM2-SLH model to investigate the global budget and cycling of tropospheric bromine, and its associated impacts on atmospheric chemistry cycles including ozone. |
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| Publication Date | Dec 19, 2025 |
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| OpenSky Citable URL | https://n2t.net/ark:/85065/d7c251xn |
| OpenSky Listing | View on OpenSky |
| CGD Affiliations | AMP |