Water mass pathways to the North Atlantic oxygen minimum zone
The water mass pathways to the North Atlantic Oxygen Minimum Zone (naOMZ) are traditionally sketched within the cyclonic tropical circulation via the poleward branching from the eastward flowing jets that lie south of 10°N. However, our water mass analysis of historic hydrographic observations toget...
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ftunivutrecht:oai:dspace.library.uu.nl:1874/350526 2023-07-23T04:20:31+02:00 Water mass pathways to the North Atlantic oxygen minimum zone Peña-Izquierdo, Jesús van Sebille, Erik Pelegrí, Josep L. Sprintall, Janet Mason, Evan Llanillo, Pedro J. Machín, Francisco Sub Physical Oceanography Marine and Atmospheric Research 2015 image/pdf https://dspace.library.uu.nl/handle/1874/350526 en eng 2169-9275 https://dspace.library.uu.nl/handle/1874/350526 info:eu-repo/semantics/OpenAccess Lagrangian pathways Oxygen minimum zone Subtropical cell Thermocline circulation Tropical Atlantic Water masses Geophysics Oceanography Forestry Ecology Aquatic Science Water Science and Technology Soil Science Geochemistry and Petrology Earth-Surface Processes Atmospheric Science Earth and Planetary Sciences (miscellaneous) Space and Planetary Science Palaeontology Article 2015 ftunivutrecht 2023-07-02T02:07:59Z The water mass pathways to the North Atlantic Oxygen Minimum Zone (naOMZ) are traditionally sketched within the cyclonic tropical circulation via the poleward branching from the eastward flowing jets that lie south of 10°N. However, our water mass analysis of historic hydrographic observations together with numerical Lagrangian experiments consistently reveal that the potential density level of σθ=26.8 kg m-3 (σ26.8, approximately 300 m depth) separates two distinct regimes of circulation within the Central Water (CW) stratum of the naOMZ. In the upper CW (above σ26.8), and in agreement with previous studies, the supply of water mainly comes from the south with a predominant contribution of South Atlantic CW. In the lower CW (below σ26.8), where minimal oxygen content is found, the tropical pathway is instead drastically weakened in favor of a subtropical pathway. More than two thirds of the total water supply to this lower layer takes place north of 10°N, mainly via an eastward flow at 14°N and northern recirculations from the northern subtropical gyre. The existence of these northern jets explains the greater contribution of North Atlantic CW observed in the lower CW, making up to 50% of the water mass at the naOMZ core. The equatorward transfer of mass from the well-ventilated northern subtropical gyre emerges as an essential part of the ventilation of the naOMZ. Article in Journal/Newspaper North Atlantic Utrecht University Repository |
institution |
Open Polar |
collection |
Utrecht University Repository |
op_collection_id |
ftunivutrecht |
language |
English |
topic |
Lagrangian pathways Oxygen minimum zone Subtropical cell Thermocline circulation Tropical Atlantic Water masses Geophysics Oceanography Forestry Ecology Aquatic Science Water Science and Technology Soil Science Geochemistry and Petrology Earth-Surface Processes Atmospheric Science Earth and Planetary Sciences (miscellaneous) Space and Planetary Science Palaeontology |
spellingShingle |
Lagrangian pathways Oxygen minimum zone Subtropical cell Thermocline circulation Tropical Atlantic Water masses Geophysics Oceanography Forestry Ecology Aquatic Science Water Science and Technology Soil Science Geochemistry and Petrology Earth-Surface Processes Atmospheric Science Earth and Planetary Sciences (miscellaneous) Space and Planetary Science Palaeontology Peña-Izquierdo, Jesús van Sebille, Erik Pelegrí, Josep L. Sprintall, Janet Mason, Evan Llanillo, Pedro J. Machín, Francisco Water mass pathways to the North Atlantic oxygen minimum zone |
topic_facet |
Lagrangian pathways Oxygen minimum zone Subtropical cell Thermocline circulation Tropical Atlantic Water masses Geophysics Oceanography Forestry Ecology Aquatic Science Water Science and Technology Soil Science Geochemistry and Petrology Earth-Surface Processes Atmospheric Science Earth and Planetary Sciences (miscellaneous) Space and Planetary Science Palaeontology |
description |
The water mass pathways to the North Atlantic Oxygen Minimum Zone (naOMZ) are traditionally sketched within the cyclonic tropical circulation via the poleward branching from the eastward flowing jets that lie south of 10°N. However, our water mass analysis of historic hydrographic observations together with numerical Lagrangian experiments consistently reveal that the potential density level of σθ=26.8 kg m-3 (σ26.8, approximately 300 m depth) separates two distinct regimes of circulation within the Central Water (CW) stratum of the naOMZ. In the upper CW (above σ26.8), and in agreement with previous studies, the supply of water mainly comes from the south with a predominant contribution of South Atlantic CW. In the lower CW (below σ26.8), where minimal oxygen content is found, the tropical pathway is instead drastically weakened in favor of a subtropical pathway. More than two thirds of the total water supply to this lower layer takes place north of 10°N, mainly via an eastward flow at 14°N and northern recirculations from the northern subtropical gyre. The existence of these northern jets explains the greater contribution of North Atlantic CW observed in the lower CW, making up to 50% of the water mass at the naOMZ core. The equatorward transfer of mass from the well-ventilated northern subtropical gyre emerges as an essential part of the ventilation of the naOMZ. |
author2 |
Sub Physical Oceanography Marine and Atmospheric Research |
format |
Article in Journal/Newspaper |
author |
Peña-Izquierdo, Jesús van Sebille, Erik Pelegrí, Josep L. Sprintall, Janet Mason, Evan Llanillo, Pedro J. Machín, Francisco |
author_facet |
Peña-Izquierdo, Jesús van Sebille, Erik Pelegrí, Josep L. Sprintall, Janet Mason, Evan Llanillo, Pedro J. Machín, Francisco |
author_sort |
Peña-Izquierdo, Jesús |
title |
Water mass pathways to the North Atlantic oxygen minimum zone |
title_short |
Water mass pathways to the North Atlantic oxygen minimum zone |
title_full |
Water mass pathways to the North Atlantic oxygen minimum zone |
title_fullStr |
Water mass pathways to the North Atlantic oxygen minimum zone |
title_full_unstemmed |
Water mass pathways to the North Atlantic oxygen minimum zone |
title_sort |
water mass pathways to the north atlantic oxygen minimum zone |
publishDate |
2015 |
url |
https://dspace.library.uu.nl/handle/1874/350526 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
2169-9275 https://dspace.library.uu.nl/handle/1874/350526 |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1772184951289020416 |