Publication Date:
2023-02-08
Description:
Transport of air masses from the subtropics, enriched in trace gases from the oceans, coasts and islands, towards lower latitudes under the trade inversion and uplift to the stratosphere in tropical deep convection.
The organic bromine compounds bromoform (CHBr 3 ) and dibromomethane (CH 2 Br 2 ) influence tropospheric chemistry and stratospheric ozone depletion. Their atmospheric abundance is generally related to a common marine source, which is not well characterized. A cruise between the three Macaroenesian Archipelagos of Cape Verde, the Canaries and Madeira revealed that anthropogenic sources increased oceanic CHBr 3 emissions significantly close to some islands, especially at the Canaries, while heterotrophic processes in the ocean increased the flux of CH 2 Br 2 from the sea to the atmosphere in the Cape Verde region. As anthropogenic disinfection processes, which release CHBr 3 in coastal areas increase, and as more CH 2 Br 2 may be produced from increased heterotrophy in a warming, deoxygenated ocean, both sources could supply higher fractions of stratospheric bromine in the future, with yet unknown consequences for stratospheric ozone.
Type:
Article
,
PeerReviewed
Format:
text
Format:
text
Format:
text
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