Atlantic Equatorial Undercurrent intensification counteracts warming-induced deoxygenation.

Brandt, Peter , Hahn, Johannes , Schmidtko, Sunke , Tuchen, Franz Philip , Kopte, Robert , Kiko, Rainer , Bourlès, Bernard, Czeschel, Rena and Dengler, Marcus (2021) Atlantic Equatorial Undercurrent intensification counteracts warming-induced deoxygenation. Open Access Nature Geoscience, 14 . pp. 278-282. DOI 10.1038/s41561-021-00716-1.

[thumbnail of manuscript_final.pdf]
manuscript_final.pdf - Accepted Version

Download (1MB) | Preview
[thumbnail of s41561-021-00716-1.pdf] Text
s41561-021-00716-1.pdf - Published Version
Restricted to Registered users only

Download (2MB) | Contact

Supplementary data:


The tropical Atlantic upper-ocean circulation experiences multiannual to decadal changes associated with different climate modes and is simultaneously adjusting to climate warming. The most energetic current in the tropical Atlantic is the Equatorial Undercurrent (EUC), which flows eastwards along the Equator. On the basis of long-term moored observations, we show that the EUC strengthened by more than 20% from 2008 to 2018. The intensification of the EUC is associated with increasing subsurface oxygen concentrations and a thickening of the upper-ocean oxygenated layer in the equatorial Atlantic. These changes counteract climate-warming-induced deoxygenation in the region. The EUC strengthening is found to be mainly forced by trade wind changes in the western tropical North Atlantic. A 60-yr dataset reveals that the recent oxygen increase in the upper equatorial Atlantic is associated with multidecadal variability. This variability is characterized by low oxygen concentrations in the 1990s and early 2000s, and high oxygen concentrations in the 1960s and 1970s. The observed oxygen variability seems to be linked to a compression and expansion of the habitat of tropical pelagic fish, and must be accounted for when evaluating the possible consequences of deoxygenation for marine ecosystems and fisheries.

Document Type: Article
Funder compliance: info:eu-repo/grantAgreement/EC/H2020/817578
Keywords: ocean circulation; oceanography
Research affiliation: OceanRep > SFB 754
OceanRep > GEOMAR > FB3 Marine Ecology > FB3-EOE-B Experimental Ecology - Benthic Ecology
OceanRep > GEOMAR > FB1 Ocean Circulation and Climate Dynamics > FB1-PO Physical Oceanography
Kiel University
Main POF Topic: PT2: Ocean and Cryosphere
Refereed: Yes
Open Access Journal?: No
Publisher: Springer
Related URLs:
Projects: TRIATLAS, SFB754, BMBF Nordatlantik, RACE, PIRATA
Date Deposited: 30 Apr 2021 12:26
Last Modified: 08 Feb 2023 09:45

Actions (login required)

View Item View Item