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1. Implications of Snowpack Reactive Bromine Production for Arctic Ice Core Bromine Preservation

   https://doi.org/10.1029/2023JD039257  

   Zhai, Shuting; Swanson, William; McConnell, Joseph R.; Chellman, Nathan; Opel, Thomas; Sigl, Michael; Meyer, Hanno; Wang, Xuan; Jaeglé, Lyatt; Stutz, Jochen; et al (October 2023, Journal of Geophysical Research: Atmospheres)

   Abstract Snowpack emissions are recognized as an important source of gas‐phase reactive bromine in the Arctic and are necessary to explain ozone depletion events in spring caused by the catalytic destruction of ozone by halogen radicals. Quantifying bromine emissions from snowpack is essential for interpretation of ice‐core bromine. We present ice‐core bromine records since the pre‐industrial (1750 CE) from six Arctic locations and examine potential post‐depositional loss of snowpack bromine using a global chemical transport model. Trend analysis of the ice‐core records shows that only the high‐latitude coastal Akademii Nauk (AN) ice core from the Russian Arctic preserves significant trends since pre‐industrial times that are consistent with trends in sea ice extent and anthropogenic emissions from source regions. Model simulations suggest that recycling of reactive bromine on the snow skin layer (top 1 mm) results in 9–17% loss of deposited bromine across all six ice‐core locations. Reactive bromine production from below the snow skin layer and within the snow photic zone is potentially more important, but the magnitude of this source is uncertain. Model simulations suggest that the AN core is most likely to preserve an atmospheric signal compared to five Greenland ice cores due to its high latitude location combined with a relatively high snow accumulation rate. Understanding the sources and amount of photochemically reactive snow bromide in the snow photic zone throughout the sunlit period in the high Arctic is essential for interpreting ice‐core bromine, and warrants further lab studies and field observations at inland locations. 

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2. Sulfate production by reactive bromine: Implications for the global sulfur and reactive bromine budgets: Sulfur-Halogen Interactions

   https://doi.org/10.1002/2017GL073812  

   Chen, Q.; Schmidt, J. A.; Shah, V.; Jaeglé, L.; Sherwen, T.; Alexander, B. (July 2017, Geophysical Research Letters)
3. Anthropogenic Influence on Tropospheric Reactive Bromine Since the Pre‐industrial: Implications for Arctic Ice‐Core Bromine Trends

   https://doi.org/10.1029/2023GL107733  

   Zhai, Shuting; McConnell, Joseph R.; Chellman, Nathan; Legrand, Michel; Opel, Thomas; Meyer, Hanno; Jaeglé, Lyatt; Confer, Kaitlyn; Fujita, Koji; Wang, Xuan; et al (February 2024, Geophysical Research Letters)

   Abstract Tropospheric reactive bromine (Br_y) influences the oxidation capacity of the atmosphere by acting as a sink for ozone and nitrogen oxides. Aerosol acidity plays a crucial role in Br_yabundances through acid‐catalyzed debromination from sea‐salt‐aerosol, the largest global source. Bromine concentrations in a Russian Arctic ice‐core, Akademii Nauk, show a 3.5‐fold increase from pre‐industrial (PI) to the 1970s (peak acidity, PA), and decreased by half to 1999 (present day, PD). Ice‐core acidity mirrors this trend, showing robust correlation with bromine, especially after 1940 (r = 0.9). Model simulations considering anthropogenic emission changes alone show that atmospheric acidity is the main driver of Br_ychanges, consistent with the observed relationship between acidity and bromine. The influence of atmospheric acidity on Br_yshould be considered in interpretation of ice‐core bromine trends. 

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4. Efficient release of bromine by super-eruptions

   https://doi.org/10.1130/G49114.1  

   Waelkens, Clara M.; Stix, John; Monteleone, Brian; Burckel, Pierre (July 2021, Geology)

   Abstract Bromine is a key halogen element in the quantification of volcanic volatiles, but analytical difficulties in measuring its very low abundances have prevented progress in understanding its behavior and its role in volcanic emissions. We present a new data set of bromine, chlorine, and fluorine concentrations in melt inclusions and matrix glasses for two rhyolitic super-eruptions from the Toledo and Valles calderas, New Mexico, USA. We show that before eruption, Br and Cl were efficiently partitioned from the gas-saturated magma into a separate fluid phase, and we calculate the mass of halogens in the fluid phase. We further demonstrate that syn-eruptive magma degassing was negligible during the super-eruptions, so that the main source of halogen emissions must have been the fluid phase. If the fluid phase were erupted, the large mass of Br and Cl could have severely impacted the atmospheric chemistry upon eruption. 

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5. Bromine‐Promoted Glycosidation of Conformationally Superarmed Thioglycosides

   https://doi.org/10.1002/chem.201901969  

   Panza, Matteo; Civera, Monica; Yasomanee, Jagodige P.; Belvisi, Laura; Demchenko, Alexei V. (August 2019, Chemistry – A European Journal)