Abstract
The Tropical Atlantic Ocean has recently been the source of enormous amounts of floating Sargassum macroalgae that have started to inundate shorelines in the Caribbean, the western coast of Africa and northern Brazil. It is still unclear, however, how the surface currents carry the Sargassum, largely restricted to the upper meter of the ocean, and whether observed surface drifter trajectories and hydrodynamical ocean models can be used to simulate its pathways. Here, we analyze a dataset of two types of surface drifters (38 in total), purposely deployed in the Tropical Atlantic Ocean in July, 2019. Twenty of the surface drifters were undrogued and reached only ∼8 cm into the water, while the other 18 were standard Surface Velocity Program (SVP) drifters that all had a drogue centered around 15 m depth. We show that the undrogued drifters separate more slowly than the drogued SVP drifters, likely because of the suppressed turbulence due to convergence in wind rows, which was stronger right at the surface than at 15 m depth. Undrogued drifters were also more likely to enter the Caribbean Sea. We also show that the novel Surface and Merged Ocean Currents (SMOC) product from the Copernicus Marine Environmental Service (CMEMS) does not clearly simulate one type of drifter better than the other, highlighting the need for further improvements in assimilated hydrodynamic models in the region, for a better understanding and forecasting of Sargassum drift in the Tropical Atlantic.
Original language | English |
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Article number | 607426 |
Number of pages | 10 |
Journal | Frontiers in Marine Science |
Volume | 7 |
DOIs | |
Publication status | Published - 15 Jan 2021 |
Bibliographical note
Funding Information:The NIOZ machine and electronics shops assisted with design and construction advice for the Stokes drifters, and Philippe Delandmeter, Daan Reijnders, and Michiel Klaassen helped with final assembly. Thanks to GlobalStar for advice, and to the crew and scientists aboard NIOZ RV Pelagia cruise 64PE455. Funding. ES was partly supported through the IMMERSE project from the European Union Horizon 2020 Research and Innovation Program (grant agreement no. 821926) and the ESA World Ocean Circulation project, ESA Contract No. 4000130730/20/I-NB. RL was supported by NOAA?s Global Ocean Monitoring and Observing Program and the Atlantic Oceanographic and Meteorological Laboratory.
Funding Information:
ES was partly supported through the IMMERSE project from the European Union Horizon 2020 Research and Innovation Program (grant agreement no. 821926) and the ESA World Ocean Circulation project, ESA Contract No. 4000130730/20/I-NB. RL was supported by NOAA’s Global Ocean Monitoring and Observing Program and the Atlantic Oceanographic and Meteorological Laboratory.
Publisher Copyright:
© Copyright © 2021 van Sebille, Zettler, Wienders, Amaral-Zettler, Elipot and Lumpkin.
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
Funding
The NIOZ machine and electronics shops assisted with design and construction advice for the Stokes drifters, and Philippe Delandmeter, Daan Reijnders, and Michiel Klaassen helped with final assembly. Thanks to GlobalStar for advice, and to the crew and scientists aboard NIOZ RV Pelagia cruise 64PE455. Funding. ES was partly supported through the IMMERSE project from the European Union Horizon 2020 Research and Innovation Program (grant agreement no. 821926) and the ESA World Ocean Circulation project, ESA Contract No. 4000130730/20/I-NB. RL was supported by NOAA?s Global Ocean Monitoring and Observing Program and the Atlantic Oceanographic and Meteorological Laboratory. ES was partly supported through the IMMERSE project from the European Union Horizon 2020 Research and Innovation Program (grant agreement no. 821926) and the ESA World Ocean Circulation project, ESA Contract No. 4000130730/20/I-NB. RL was supported by NOAA’s Global Ocean Monitoring and Observing Program and the Atlantic Oceanographic and Meteorological Laboratory.
Keywords
- ocean currents
- ocean dispersion
- Sargassum
- surface drifters
- Tropical Atlantic