Jia, Yue , Hahn, Josefine , Quack, Birgit, Jones, Edward , Brehon, Meghan and Tegtmeier, Susann (2023) Anthropogenic Bromoform at the Extratropical Tropopause. Geophysical Research Letters, 50 (9). Art.Nr. e2023GL102894. DOI 10.1029/2023GL102894.

Preview	Text Jia_Quack_2023.pdf - Published Version Available under License Creative Commons: Attribution 4.0. Download (2MB) | Preview
Preview	Text d41586-023-01592-y.pdf - Supplemental Material Download (317kB) | Preview
Preview	Text 2023-05-anthropogenic-bromoform-atmosphere-thought.pdf - Supplemental Material Download (492kB) | Preview

Abstract

Key Points:
- A new CHBr3 emission inventory based on natural and anthropogenic sources suggests that the latter account for 12%–28% of the global emissions
- In the NH, new anthropogenic estimates increase known natural CHBr3 emissions by up to 70.5%, leading to higher atmospheric CHBr3 levels
- At the NH extratropical tropopause, CHBr3 is enhanced by 0.9 ppt Br due to anthropogenic sources thus doubling natural CHBr3 abundances

Bromoform (CHBr3) contributes to stratospheric ozone depletion but is not regulated under the Montreal Protocol due to its short lifetime and large natural sources. Here, we show that anthropogenic sources contribute significantly to the amount of CHBr3 transported into the Northern Hemisphere (NH) extratropical stratosphere. We present a new CHBr3 emission inventory comprised of natural and anthropogenic sources, with the latter estimated from ship ballast, power plant cooling and desalination plant brine water. Including anthropogenic sources in the new inventory increases CHBr3 emissions by up to 31.5% globally and 70.5% in the NH. In consequence, atmospheric CHBr3 is also significantly higher, especially over the NH extratropics during boreal winter. Here anthropogenic sources enhance bromine at the tropopause by 0.9 ppt Br, thus doubling natural CHBr3 abundances. For some latitudes, tropopause bromine increases by 2.4 ppt Br suggesting significant contributions of anthropogenic CHBr3 to the NH lowermost stratosphere.

Actions (login required)

View Item