Internal ocean dynamics contribution to North Atlantic interdecadal variability strengthened by ocean-atmosphere thermal coupling
Identifying the primary drivers of North Atlantic interdecadal climate variability is crucial for improving climatic prediction over the coming decades. Here the effect of thermal coupling on the leading energy sources of the interdecadal variability of the ocean-atmosphere system is examined by mea...
Published in: | Journal of Climate |
---|---|
Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
American Meteorological Society
2022
|
Subjects: | |
Online Access: | https://archimer.ifremer.fr/doc/00792/90446/96017.pdf https://doi.org/10.1175/JCLI-D-22-0191.1 https://archimer.ifremer.fr/doc/00792/90446/ |
id |
ftarchimer:oai:archimer.ifremer.fr:90446 |
---|---|
record_format |
openpolar |
spelling |
ftarchimer:oai:archimer.ifremer.fr:90446 2023-05-15T17:29:44+02:00 Internal ocean dynamics contribution to North Atlantic interdecadal variability strengthened by ocean-atmosphere thermal coupling Arzel, Olivier Huck, Thierry Hochet, Antoine Mussa, Alexandre 2022-12 application/pdf https://archimer.ifremer.fr/doc/00792/90446/96017.pdf https://doi.org/10.1175/JCLI-D-22-0191.1 https://archimer.ifremer.fr/doc/00792/90446/ eng eng American Meteorological Society https://archimer.ifremer.fr/doc/00792/90446/96017.pdf doi:10.1175/JCLI-D-22-0191.1 https://archimer.ifremer.fr/doc/00792/90446/ info:eu-repo/semantics/openAccess restricted use Journal Of Climate (0894-8755) (American Meteorological Society), 2022-12 , Vol. 35 , N. 24 , P. 4605-4624 Atmosphere-ocean interaction Stochastic models Interdecadal variability North Atlantic Ocean Internal variability text Publication info:eu-repo/semantics/article 2022 ftarchimer https://doi.org/10.1175/JCLI-D-22-0191.1 2023-03-14T23:55:22Z Identifying the primary drivers of North Atlantic interdecadal climate variability is crucial for improving climatic prediction over the coming decades. Here the effect of thermal coupling on the leading energy sources of the interdecadal variability of the ocean-atmosphere system is examined by means of a stochastically-forced idealized coupled model. The effect of coupling is quantified from a comparison of the buoyancy variance budget of coupled and uncoupled model configurations. The simplicity of the model allows us to contrast the effect of coupling between a super-critical regime where the deterministic ocean dynamics drive the variability and a damped regime where noise forcing is central to its existence. The results show that changes in surface buoyancy fluxes act as a sink of temperature variance in the super-critical regime, and only become a source in the strongly damped regime. By contrast, internal ocean dynamics associated with the interaction of transient buoyancy fluxes with mean buoyancy gradients always act as a source of interdecadal variability. In addition to the reduced thermal damping effect in coupled integrations, thermal coupling with the atmosphere is shown to significantly increase the role of internal ocean dynamics in the variability, in particular in the regime where interdecadal modes are damped. Only for oceanic background states in the strongly damped regime do changes in surface buoyancy fluxes play a leading role in the upper ocean variability. A stochastically-forced coupled box model is proposed that captures the basic effect of thermal coupling on atmospheric and oceanic energy sources of variability. Article in Journal/Newspaper North Atlantic Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) Journal of Climate 35 24 4605 4624 |
institution |
Open Polar |
collection |
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) |
op_collection_id |
ftarchimer |
language |
English |
topic |
Atmosphere-ocean interaction Stochastic models Interdecadal variability North Atlantic Ocean Internal variability |
spellingShingle |
Atmosphere-ocean interaction Stochastic models Interdecadal variability North Atlantic Ocean Internal variability Arzel, Olivier Huck, Thierry Hochet, Antoine Mussa, Alexandre Internal ocean dynamics contribution to North Atlantic interdecadal variability strengthened by ocean-atmosphere thermal coupling |
topic_facet |
Atmosphere-ocean interaction Stochastic models Interdecadal variability North Atlantic Ocean Internal variability |
description |
Identifying the primary drivers of North Atlantic interdecadal climate variability is crucial for improving climatic prediction over the coming decades. Here the effect of thermal coupling on the leading energy sources of the interdecadal variability of the ocean-atmosphere system is examined by means of a stochastically-forced idealized coupled model. The effect of coupling is quantified from a comparison of the buoyancy variance budget of coupled and uncoupled model configurations. The simplicity of the model allows us to contrast the effect of coupling between a super-critical regime where the deterministic ocean dynamics drive the variability and a damped regime where noise forcing is central to its existence. The results show that changes in surface buoyancy fluxes act as a sink of temperature variance in the super-critical regime, and only become a source in the strongly damped regime. By contrast, internal ocean dynamics associated with the interaction of transient buoyancy fluxes with mean buoyancy gradients always act as a source of interdecadal variability. In addition to the reduced thermal damping effect in coupled integrations, thermal coupling with the atmosphere is shown to significantly increase the role of internal ocean dynamics in the variability, in particular in the regime where interdecadal modes are damped. Only for oceanic background states in the strongly damped regime do changes in surface buoyancy fluxes play a leading role in the upper ocean variability. A stochastically-forced coupled box model is proposed that captures the basic effect of thermal coupling on atmospheric and oceanic energy sources of variability. |
format |
Article in Journal/Newspaper |
author |
Arzel, Olivier Huck, Thierry Hochet, Antoine Mussa, Alexandre |
author_facet |
Arzel, Olivier Huck, Thierry Hochet, Antoine Mussa, Alexandre |
author_sort |
Arzel, Olivier |
title |
Internal ocean dynamics contribution to North Atlantic interdecadal variability strengthened by ocean-atmosphere thermal coupling |
title_short |
Internal ocean dynamics contribution to North Atlantic interdecadal variability strengthened by ocean-atmosphere thermal coupling |
title_full |
Internal ocean dynamics contribution to North Atlantic interdecadal variability strengthened by ocean-atmosphere thermal coupling |
title_fullStr |
Internal ocean dynamics contribution to North Atlantic interdecadal variability strengthened by ocean-atmosphere thermal coupling |
title_full_unstemmed |
Internal ocean dynamics contribution to North Atlantic interdecadal variability strengthened by ocean-atmosphere thermal coupling |
title_sort |
internal ocean dynamics contribution to north atlantic interdecadal variability strengthened by ocean-atmosphere thermal coupling |
publisher |
American Meteorological Society |
publishDate |
2022 |
url |
https://archimer.ifremer.fr/doc/00792/90446/96017.pdf https://doi.org/10.1175/JCLI-D-22-0191.1 https://archimer.ifremer.fr/doc/00792/90446/ |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Journal Of Climate (0894-8755) (American Meteorological Society), 2022-12 , Vol. 35 , N. 24 , P. 4605-4624 |
op_relation |
https://archimer.ifremer.fr/doc/00792/90446/96017.pdf doi:10.1175/JCLI-D-22-0191.1 https://archimer.ifremer.fr/doc/00792/90446/ |
op_rights |
info:eu-repo/semantics/openAccess restricted use |
op_doi |
https://doi.org/10.1175/JCLI-D-22-0191.1 |
container_title |
Journal of Climate |
container_volume |
35 |
container_issue |
24 |
container_start_page |
4605 |
op_container_end_page |
4624 |
_version_ |
1766124515625009152 |