Vertical marine snow distribution in the stratified, hypersaline, and anoxic Orca Basin (Gulf of Mexico)
We present a complete description of the depth distribution of marine snow in Orca Basin (Gulf of Mexico), from sea surface through the pycnocline to within 10 m of the seafloor. Orca Basin is an intriguing location for studying marine snow because of its unique geological and hydrographic setting:...
Published in: | Elementa: Science of the Anthropocene |
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University of California Press
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Online Access: | http://dx.doi.org/10.1525/elementa.348 https://online.ucpress.edu/elementa/article-pdf/doi/10.1525/elementa.348/434691/348-5955-1-pb.pdf |
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crunicaliforniap:10.1525/elementa.348 2024-05-19T07:46:45+00:00 Vertical marine snow distribution in the stratified, hypersaline, and anoxic Orca Basin (Gulf of Mexico) Diercks, Arne Ziervogel, Kai Sibert, Ryan Joye, Samantha B. Asper, Vernon Montoya, Joseph P. Deming, Jody W. Thomsen, Laurenz 2019 http://dx.doi.org/10.1525/elementa.348 https://online.ucpress.edu/elementa/article-pdf/doi/10.1525/elementa.348/434691/348-5955-1-pb.pdf en eng University of California Press http://creativecommons.org/licenses/by/4.0/ Elementa: Science of the Anthropocene volume 7 ISSN 2325-1026 journal-article 2019 crunicaliforniap https://doi.org/10.1525/elementa.348 2024-05-02T10:03:50Z We present a complete description of the depth distribution of marine snow in Orca Basin (Gulf of Mexico), from sea surface through the pycnocline to within 10 m of the seafloor. Orca Basin is an intriguing location for studying marine snow because of its unique geological and hydrographic setting: the deepest ~200 m of the basin are filled with anoxic hypersaline brine. A typical deep ocean profile of marine snow distribution was observed from the sea surface to the pycnocline, namely a surface maximum in total particle number and midwater minimum. However, instead of a nepheloid (particle-rich) layer positioned near the seabed, the nepheloid layer in the Orca Basin was positioned atop the brine. Within the brine, the total particle volume increased by a factor of 2–3 while the total particle number decreased, indicating accumulation and aggregation of material in the brine. From these observations we infer increased residence time and retention of material within the brine, which agrees well with laboratory results showing a 2.2–3.5-fold reduction in settling speed of laboratory-generated marine snow below the seawater-brine interface. Similarly, dissolved organic carbon concentration in the brine correlated positively with measured colored dissolved organic matter (r2 = 0.92, n = 15), with both variables following total particle volume inversely through the pycnocline. These data indicate the release of dissolved organic carbon concomitant with loss in total particle volume and increase in particle numbers at the brine-seawater interface, highlighting the importance of the Orca Basin as a carbon sink. Article in Journal/Newspaper Orca University of California Press Elementa: Science of the Anthropocene 7 |
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Open Polar |
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University of California Press |
op_collection_id |
crunicaliforniap |
language |
English |
description |
We present a complete description of the depth distribution of marine snow in Orca Basin (Gulf of Mexico), from sea surface through the pycnocline to within 10 m of the seafloor. Orca Basin is an intriguing location for studying marine snow because of its unique geological and hydrographic setting: the deepest ~200 m of the basin are filled with anoxic hypersaline brine. A typical deep ocean profile of marine snow distribution was observed from the sea surface to the pycnocline, namely a surface maximum in total particle number and midwater minimum. However, instead of a nepheloid (particle-rich) layer positioned near the seabed, the nepheloid layer in the Orca Basin was positioned atop the brine. Within the brine, the total particle volume increased by a factor of 2–3 while the total particle number decreased, indicating accumulation and aggregation of material in the brine. From these observations we infer increased residence time and retention of material within the brine, which agrees well with laboratory results showing a 2.2–3.5-fold reduction in settling speed of laboratory-generated marine snow below the seawater-brine interface. Similarly, dissolved organic carbon concentration in the brine correlated positively with measured colored dissolved organic matter (r2 = 0.92, n = 15), with both variables following total particle volume inversely through the pycnocline. These data indicate the release of dissolved organic carbon concomitant with loss in total particle volume and increase in particle numbers at the brine-seawater interface, highlighting the importance of the Orca Basin as a carbon sink. |
author2 |
Deming, Jody W. Thomsen, Laurenz |
format |
Article in Journal/Newspaper |
author |
Diercks, Arne Ziervogel, Kai Sibert, Ryan Joye, Samantha B. Asper, Vernon Montoya, Joseph P. |
spellingShingle |
Diercks, Arne Ziervogel, Kai Sibert, Ryan Joye, Samantha B. Asper, Vernon Montoya, Joseph P. Vertical marine snow distribution in the stratified, hypersaline, and anoxic Orca Basin (Gulf of Mexico) |
author_facet |
Diercks, Arne Ziervogel, Kai Sibert, Ryan Joye, Samantha B. Asper, Vernon Montoya, Joseph P. |
author_sort |
Diercks, Arne |
title |
Vertical marine snow distribution in the stratified, hypersaline, and anoxic Orca Basin (Gulf of Mexico) |
title_short |
Vertical marine snow distribution in the stratified, hypersaline, and anoxic Orca Basin (Gulf of Mexico) |
title_full |
Vertical marine snow distribution in the stratified, hypersaline, and anoxic Orca Basin (Gulf of Mexico) |
title_fullStr |
Vertical marine snow distribution in the stratified, hypersaline, and anoxic Orca Basin (Gulf of Mexico) |
title_full_unstemmed |
Vertical marine snow distribution in the stratified, hypersaline, and anoxic Orca Basin (Gulf of Mexico) |
title_sort |
vertical marine snow distribution in the stratified, hypersaline, and anoxic orca basin (gulf of mexico) |
publisher |
University of California Press |
publishDate |
2019 |
url |
http://dx.doi.org/10.1525/elementa.348 https://online.ucpress.edu/elementa/article-pdf/doi/10.1525/elementa.348/434691/348-5955-1-pb.pdf |
genre |
Orca |
genre_facet |
Orca |
op_source |
Elementa: Science of the Anthropocene volume 7 ISSN 2325-1026 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1525/elementa.348 |
container_title |
Elementa: Science of the Anthropocene |
container_volume |
7 |
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1799486996764164096 |