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Cited by 78Oceanographic and Atmospheric ProcessesClimate variability and modelsMarine and coastal ecosystems

The Angola Current: Flow and hydrographic characteristics as observed at 11°S: THE ANGOLA CURRENT AS OBSERVED AT 11°S

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Kopte, R., Brandt, P., Dengler, M., Tchipalanga, P. C. M., Macuéria, M., Ostrowski, M.·2017·Journal of Geophysical Research: Oceans
DOI 10.1002/2016jc012374
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Abstract

The eastern boundary circulation off the coast of Angola has been described only sparsely to date, although it is a key element in the understanding of the highly productive tropical marine ecosystem off Angola. Here, we report for the first time direct velocity observations of the Angola Current (AC) at ∼11°S collected between July 2013 and October 2015 in the depth range from 45 to 450 m. The measurements reveal an alongshore flow that is dominated by intraseasonal to seasonal variability with periodically alternating southward and northward velocities in the range of ±40 cm/s. During the observation period, a weak southward mean flow of 5–8 cm/s at 50 m depth is observed, with the southward current extending down to about 200 m depth. Corresponding mean southward transport of the AC is estimated to be 0.32 ± 0.046 Sv. An extensive set of hydrographic measurements is used to investigate the thermal structure and seasonality in the hydrography of the eastern boundary circulation. Within the depth range of the AC, the superposition of annual and semiannual harmonics explains a significant part of the total variability, although salinity in the near surface layer appears to be also impacted by year-to-year variability and/or short-term freshening events. In the central water layer, temperature and salinity on isopycnals vary only weakly on seasonal to annual time scales. The available data set is further used to evaluate different reanalysis products particularly emphasizing the ocean's role in coupled climate model SST biases in the Eastern Tropical Atlantic.

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  • Relatively little is known about the vertical structure and seasonality of the poleward Angola current, though data from recently deployed buoys are beginning to shed light on it.

    “Relatively little is known about the vertical structure and seasonality of the poleward Angola current (Tchipalanga et al., 2018), though data from recently deployed buoys in the region are beginning to shed some light on this (Kopte et al., 2017).”

    From The tropical atlantic observing system (2019) · cites this paper as Kopte et al., 2017

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Cited by

Sorted by citations

  • The tropical atlantic observing system

    Foltz, G. R., Brandt, P., Richter, I., Rodríguez-Fonseca, B., Hernandez, F., Dengler, M., Rodrigues, R. R., Schmidt, J. O., Yu, L., Lefevre, N., et al. (2019) · Frontiers in Marine Science · doi:10.3389/fmars.2019.00206 · Cited by 150 · see citing works

    “…14 May 2019 | Volume 6 | Article 206 Relatively little is known about the vertical structure and seasonality of the poleward Angola current (Tchipalanga et al., 2018), though data from recently deployed buoys in the region are beginning to shed some light on this (Kopte et al., 2017).”
    BackgroundSelf-citation

Authors
Kopte, R., Brandt, P., Dengler, M., Tchipalanga, P. C. M., Macuéria, M., & Ostrowski, M.
Affiliations
  • GEOMAR Helmholtz Centre for Ocean Research Kiel (DE)
  • Christian-Albrechts-Universität zu Kiel (DE)
  • Instituto Nacional de Investigação Pesqueira (AO)
  • Norwegian Institute of Marine Research (NO)
Corresponding author
Kopte, R.
ORCID
Venue
Journal of Geophysical Research: Oceans
Publisher
American Geophysical Union (AGU)
Published
2017-02
Volume
122
Issue
2
Pages
1177-1189
ISSN
2169-9275 (ISSN-L)
DOI
10.1002/2016jc012374
OpenAlex
W2569948976
Cited by
78
References
3
Citations by year
2026: 5 · 2025: 6 · 2024: 13 · 2023: 13 · 2022: 7 · 2021: 10 · 2020: 3 · 2019: 11 · 2018: 7 · 2017: 3
FWCI
4.73
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Geophysical Research Oceans (publishedVersion, cc-by-nc-nd)
  • Helmholtz Centre for Ocean Research Kiel (GEOMAR) (acceptedVersion, other-oa)
  • NORA - Norwegian Open Research Archives (submittedVersion, other-oa)
Funders
  • German Federal Ministry of Education and Research as part of the SACUS project ((03G0837A))
  • European Union 7th Framework Programme ((FP7 2007-2013), 603521)
  • Norwegian Agency for Development Cooperation (Norad)
Topics
  • Physical Sciences › Earth and Planetary Sciences › Oceanography › Oceanographic and Atmospheric Processes
  • Physical Sciences › Environmental Science › Global and Planetary Change › Climate variability and models
  • Physical Sciences › Earth and Planetary Sciences › Oceanography › Marine and coastal ecosystems
Keywords
Angola Current, eastern boundary currents, alongshore flow, seasonal variation, hydrographic structure, salinity change, temperature variability, reanalysis evaluation, sea surface temperature bias, eastern tropical Atlantic, tropical marine ecosystems

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