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Title: The source and accumulation of anthropogenic carbon in the U.S. East Coast
The ocean has absorbed anthropogenic carbon dioxide (Canthro) from the atmosphere and played an important role in mitigating global warming. However, how much Canthrois accumulated in coastal oceans and where it comes from have rarely been addressed with observational data. Here, we use a high-quality carbonate dataset (1996–2018) in the U.S. East Coast to address these questions. Our work shows that the offshore slope waters have the highest Canthroaccumulation changes (ΔCanthro) consistent with water mass age and properties. From offshore to nearshore, ΔCanthrodecreases with salinity to near zero in the subsurface, indicating no net increase in the export of Canthrofrom estuaries and wetlands. Excesses over the conservative mixing baseline also reveal an uptake of Canthrofrom the atmosphere within the shelf. Our analysis suggests that the continental shelf exports most of its absorbed Canthrofrom the atmosphere to the open ocean and acts as an essential pathway for global ocean Canthrostorage and acidification.  more » « less
Award ID(s):
2123768
PAR ID:
10541476
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science Advances
Volume:
10
Issue:
32
ISSN:
2375-2548
Subject(s) / Keyword(s):
Continental shelves export anthropogenic carbon absorbed from the atmosphere but receive nearly zero from estuaries. Continental shelves receive little anthropogenic carbon from estuaries but transport it from the atmosphere to the open ocean.
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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