دورية أكاديمية
Tropospheric Bromine Chemistry: Implications for Present and Pre-Industrial Ozone and Mercury
| العنوان: | Tropospheric Bromine Chemistry: Implications for Present and Pre-Industrial Ozone and Mercury |
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| المؤلفون: | Parrella, J. P., Jacob, Daniel J., Liang, Q., Zhang, Y., Mickley, Loretta J., Miller, Benjamin Franklin, Evans, M. J., Yang, X., Pyle, J. A., Theys, N., Van Roozendael, M. |
| بيانات النشر: | European Geosciences Union |
| سنة النشر: | 2012 |
| المجموعة: | Harvard University: DASH - Digital Access to Scholarship at Harvard |
| الوصف: | We present a new model for the global tropospheric chemistry of inorganic bromine (Bry) coupled to oxidant-aerosol chemistry in the GEOS-Chem chemical transport model (CTM). Sources of tropospheric Bry include debromination of sea-salt aerosol, photolysis and oxidation of short-lived bromocarbons, and transport from the stratosphere. Comparison to a GOME-2 satellite climatology of tropospheric BrO columns shows that the model can reproduce the observed increase of BrO with latitude, the northern mid-latitudes maximum in winter, and the Arctic maximum in spring. This successful simulation is contingent on the HOBr + HBr reaction taking place in aqueous aerosols and ice clouds. Bromine chemistry in the model decreases tropospheric ozone mixing ratios by <1–8 nmol mol−1 (6.5% globally), with the largest effects in the northern extratropics in spring. The global mean tropospheric OH concentration decreases by 4%. Inclusion of bromine chemistry improves the ability of global models (GEOS-Chem and p-TOMCAT) to simulate observed 19th-century ozone and its seasonality. Bromine effects on tropospheric ozone are comparable in the present-day and pre-industrial atmospheres so that estimates of anthropogenic radiative forcing are minimally affected. Br atom concentrations are 40% higher in the pre-industrial atmosphere due to lower ozone, which would decrease by a factor of 2 the atmospheric lifetime of elemental mercury against oxidation by Br. This suggests that historical anthropogenic mercury emissions may have mostly deposited to northern mid-latitudes, enriching the corresponding surface reservoirs. The persistent rise in background surface ozone at northern mid-latitudes during the past decades could possibly contribute to the observations of elevated mercury in subsurface waters of the North Atlantic. ; Engineering and Applied Sciences ; Version of Record |
| نوع الوثيقة: | article in journal/newspaper |
| وصف الملف: | application/pdf |
| اللغة: | English |
| تدمد: | 1680-7316 1680-7324 |
| العلاقة: | Atmospheric Chemistry and Physics; Parrella, J. P., D. J. Jacob, Q. Liang, Y. Zhang, L. J. Mickley, B. Miller, M. J. Evans, et al. 2012. Tropospheric Bromine Chemistry: Implications for Present and Pre-Industrial Ozone and Mercury. Atmospheric Chemistry and Physics 12, no. 15: 6723–6740.; http://nrs.harvard.edu/urn-3:HUL.InstRepos:11916599Test |
| DOI: | 10.5194/acp-12-6723-2012 |
| الإتاحة: | https://doi.org/10.5194/acp-12-6723-2012Test http://nrs.harvard.edu/urn-3:HUL.InstRepos:11916599Test |
| رقم الانضمام: | edsbas.6C0793E1 |
| قاعدة البيانات: | BASE |
Full Text Finder | تدمد: | 16807316 16807324 |
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| DOI: | 10.5194/acp-12-6723-2012 |