Distribution of suspended particulate matter at the equatorial transect in the Atlantic Ocean
A suspended particulate matter distribution against a hydrographical background was studied at the oceanographic transect across the equatorial Atlantic in the year 2000. An area of abnormally high suspended matter volume concentrations was found above the Sierra Leone Rise in the entire water colum...
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ftcopernicus:oai:publications.copernicus.org:os94715 2023-05-15T14:02:17+02:00 Distribution of suspended particulate matter at the equatorial transect in the Atlantic Ocean Sivkov, Vadim Bubnova, Ekaterina 2021-10-21 application/pdf https://doi.org/10.5194/os-17-1421-2021 https://os.copernicus.org/articles/17/1421/2021/ eng eng doi:10.5194/os-17-1421-2021 https://os.copernicus.org/articles/17/1421/2021/ eISSN: 1812-0792 Text 2021 ftcopernicus https://doi.org/10.5194/os-17-1421-2021 2021-10-25T16:22:29Z A suspended particulate matter distribution against a hydrographical background was studied at the oceanographic transect across the equatorial Atlantic in the year 2000. An area of abnormally high suspended matter volume concentrations was found above the Sierra Leone Rise in the entire water column (eastern part of the transect). The suggested explanation for the anomaly is based on the ballast hypothesis whereby solid particles are incorporated as ballast into suspended biogenic aggregates, leading to increased velocities of sinking. This occurs within the Northwest African upwelling area, where the plankton exposed to the Saharan dust abundance form a significant number of aggregates, which are later transported equatorward via the Canary Current. An intermediate nepheloid layer associated with the Deep Western Boundary Current was recorded from the South American Slope at depths of 3200–3700 to 4300 m above the Para Abyssal Plain. Antarctic Bottom Water enriched in suspended matter was found mostly in the troughs at 40–41 ∘ W. It was detached from the bottom, coinciding with the core of the flow due to the bottom rise “dam” located up-stream. The grain size of particles along the entire transect has a polymodal distribution with 2–4 and 8–13 µm modes. The registered rise in percentage in some parts of the transect of the 7–21 µm sized particles suggests the presence of the well-known coarse mode (20–60 µm ) formed by aggregation of transparent exopolymer particles (mucus). Text Antarc* Antarctic Copernicus Publications: E-Journals Antarctic Ocean Science 17 5 1421 1435 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
A suspended particulate matter distribution against a hydrographical background was studied at the oceanographic transect across the equatorial Atlantic in the year 2000. An area of abnormally high suspended matter volume concentrations was found above the Sierra Leone Rise in the entire water column (eastern part of the transect). The suggested explanation for the anomaly is based on the ballast hypothesis whereby solid particles are incorporated as ballast into suspended biogenic aggregates, leading to increased velocities of sinking. This occurs within the Northwest African upwelling area, where the plankton exposed to the Saharan dust abundance form a significant number of aggregates, which are later transported equatorward via the Canary Current. An intermediate nepheloid layer associated with the Deep Western Boundary Current was recorded from the South American Slope at depths of 3200–3700 to 4300 m above the Para Abyssal Plain. Antarctic Bottom Water enriched in suspended matter was found mostly in the troughs at 40–41 ∘ W. It was detached from the bottom, coinciding with the core of the flow due to the bottom rise “dam” located up-stream. The grain size of particles along the entire transect has a polymodal distribution with 2–4 and 8–13 µm modes. The registered rise in percentage in some parts of the transect of the 7–21 µm sized particles suggests the presence of the well-known coarse mode (20–60 µm ) formed by aggregation of transparent exopolymer particles (mucus). |
format |
Text |
author |
Sivkov, Vadim Bubnova, Ekaterina |
spellingShingle |
Sivkov, Vadim Bubnova, Ekaterina Distribution of suspended particulate matter at the equatorial transect in the Atlantic Ocean |
author_facet |
Sivkov, Vadim Bubnova, Ekaterina |
author_sort |
Sivkov, Vadim |
title |
Distribution of suspended particulate matter at the equatorial transect in the Atlantic Ocean |
title_short |
Distribution of suspended particulate matter at the equatorial transect in the Atlantic Ocean |
title_full |
Distribution of suspended particulate matter at the equatorial transect in the Atlantic Ocean |
title_fullStr |
Distribution of suspended particulate matter at the equatorial transect in the Atlantic Ocean |
title_full_unstemmed |
Distribution of suspended particulate matter at the equatorial transect in the Atlantic Ocean |
title_sort |
distribution of suspended particulate matter at the equatorial transect in the atlantic ocean |
publishDate |
2021 |
url |
https://doi.org/10.5194/os-17-1421-2021 https://os.copernicus.org/articles/17/1421/2021/ |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
eISSN: 1812-0792 |
op_relation |
doi:10.5194/os-17-1421-2021 https://os.copernicus.org/articles/17/1421/2021/ |
op_doi |
https://doi.org/10.5194/os-17-1421-2021 |
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Ocean Science |
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17 |
container_issue |
5 |
container_start_page |
1421 |
op_container_end_page |
1435 |
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1766272468437172224 |