A new method to assess mesoscale contributions to meridional heat transport in the North Atlantic Ocean
The meridional heat transport (MHT) in the North Atlantic is critically important to climate variability and the global overturning circulation. A wide range of ocean processes contribute to North Atlantic MHT, ranging from basin-scale overturning and gyre motions to mesoscale instabilities (such as...
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Copernicus Publications
2020
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00052929 2023-05-15T17:30:10+02:00 A new method to assess mesoscale contributions to meridional heat transport in the North Atlantic Ocean Delman, Andrew Lee, Tong 2020-08 electronic https://doi.org/10.5194/os-16-979-2020 https://noa.gwlb.de/receive/cop_mods_00052929 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00052582/os-16-979-2020.pdf https://os.copernicus.org/articles/16/979/2020/os-16-979-2020.pdf eng eng Copernicus Publications Ocean Science -- http://www.bibliothek.uni-regensburg.de/ezeit/?2183769 -- http://www.copernicus.org/EGU/os/os.html -- 1812-0792 https://doi.org/10.5194/os-16-979-2020 https://noa.gwlb.de/receive/cop_mods_00052929 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00052582/os-16-979-2020.pdf https://os.copernicus.org/articles/16/979/2020/os-16-979-2020.pdf https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess CC-BY article Verlagsveröffentlichung article Text doc-type:article 2020 ftnonlinearchiv https://doi.org/10.5194/os-16-979-2020 2022-02-08T22:35:43Z The meridional heat transport (MHT) in the North Atlantic is critically important to climate variability and the global overturning circulation. A wide range of ocean processes contribute to North Atlantic MHT, ranging from basin-scale overturning and gyre motions to mesoscale instabilities (such as eddies). However, previous analyses of “eddy” MHT in the region have mostly focused on the contributions of time-variable velocity and temperature, rather than considering the association of MHT with distinct spatial scales within the basin. In this study, a zonal spatial-scale decomposition separates large-scale from mesoscale velocity and temperature contributions to MHT, in order to characterize the physical processes driving MHT. Using this approach, we found that the mesoscale contributions to the time-mean and interannual/decadal (ID) variability of MHT in the latitude range 39–45∘ N are larger than large-scale horizontal contributions, though smaller than the overturning contributions. Considering the 40∘ N transect as a case study, large-scale ID variability is mostly generated close to the western boundary. In contrast, most ID MHT variability associated with mesoscales originates in two distinct regions: a western boundary region (70–60∘ W) associated with 1- to 4-year interannual variations and an interior region (50–35∘ W) associated with decadal variations. Surface eddy kinetic energy is not a reliable indicator of high MHT episodes, but the large-scale meridional temperature gradient is an important factor, by influencing the local temperature variance as well as the local correlation of velocity and temperature. Most of the mesoscale contribution to MHT at 40∘ N is associated with transient and propagating processes, but stationary mesoscale structures explain most of the mesoscale MHT south of the Gulf Stream separation, highlighting the differences between the temporal and spatial decomposition of meridional temperature fluxes. Article in Journal/Newspaper North Atlantic Niedersächsisches Online-Archiv NOA Ocean Science 16 4 979 995 |
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article Verlagsveröffentlichung Delman, Andrew Lee, Tong A new method to assess mesoscale contributions to meridional heat transport in the North Atlantic Ocean |
topic_facet |
article Verlagsveröffentlichung |
description |
The meridional heat transport (MHT) in the North Atlantic is critically important to climate variability and the global overturning circulation. A wide range of ocean processes contribute to North Atlantic MHT, ranging from basin-scale overturning and gyre motions to mesoscale instabilities (such as eddies). However, previous analyses of “eddy” MHT in the region have mostly focused on the contributions of time-variable velocity and temperature, rather than considering the association of MHT with distinct spatial scales within the basin. In this study, a zonal spatial-scale decomposition separates large-scale from mesoscale velocity and temperature contributions to MHT, in order to characterize the physical processes driving MHT. Using this approach, we found that the mesoscale contributions to the time-mean and interannual/decadal (ID) variability of MHT in the latitude range 39–45∘ N are larger than large-scale horizontal contributions, though smaller than the overturning contributions. Considering the 40∘ N transect as a case study, large-scale ID variability is mostly generated close to the western boundary. In contrast, most ID MHT variability associated with mesoscales originates in two distinct regions: a western boundary region (70–60∘ W) associated with 1- to 4-year interannual variations and an interior region (50–35∘ W) associated with decadal variations. Surface eddy kinetic energy is not a reliable indicator of high MHT episodes, but the large-scale meridional temperature gradient is an important factor, by influencing the local temperature variance as well as the local correlation of velocity and temperature. Most of the mesoscale contribution to MHT at 40∘ N is associated with transient and propagating processes, but stationary mesoscale structures explain most of the mesoscale MHT south of the Gulf Stream separation, highlighting the differences between the temporal and spatial decomposition of meridional temperature fluxes. |
format |
Article in Journal/Newspaper |
author |
Delman, Andrew Lee, Tong |
author_facet |
Delman, Andrew Lee, Tong |
author_sort |
Delman, Andrew |
title |
A new method to assess mesoscale contributions to meridional heat transport in the North Atlantic Ocean |
title_short |
A new method to assess mesoscale contributions to meridional heat transport in the North Atlantic Ocean |
title_full |
A new method to assess mesoscale contributions to meridional heat transport in the North Atlantic Ocean |
title_fullStr |
A new method to assess mesoscale contributions to meridional heat transport in the North Atlantic Ocean |
title_full_unstemmed |
A new method to assess mesoscale contributions to meridional heat transport in the North Atlantic Ocean |
title_sort |
new method to assess mesoscale contributions to meridional heat transport in the north atlantic ocean |
publisher |
Copernicus Publications |
publishDate |
2020 |
url |
https://doi.org/10.5194/os-16-979-2020 https://noa.gwlb.de/receive/cop_mods_00052929 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00052582/os-16-979-2020.pdf https://os.copernicus.org/articles/16/979/2020/os-16-979-2020.pdf |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
Ocean Science -- http://www.bibliothek.uni-regensburg.de/ezeit/?2183769 -- http://www.copernicus.org/EGU/os/os.html -- 1812-0792 https://doi.org/10.5194/os-16-979-2020 https://noa.gwlb.de/receive/cop_mods_00052929 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00052582/os-16-979-2020.pdf https://os.copernicus.org/articles/16/979/2020/os-16-979-2020.pdf |
op_rights |
https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/os-16-979-2020 |
container_title |
Ocean Science |
container_volume |
16 |
container_issue |
4 |
container_start_page |
979 |
op_container_end_page |
995 |
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1766125991642529792 |