Initialization shock in the ocean circulation reduces skill in decadal predictions of the North Atlantic subpolar gyre
Due to large northward heat transport, the Atlantic meridional overturning circulation (AMOC) strongly affects the climate of various regions. Its internal variability has been shown to be predictable decades ahead within climate models, providing the hope that synchronizing ocean circulation with o...
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Online Access: | https://hdl.handle.net/11250/3123385 https://doi.org/10.3389/fclim.2023.1273770 |
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ftunivbergen:oai:bora.uib.no:11250/3123385 2024-04-21T08:07:41+00:00 Initialization shock in the ocean circulation reduces skill in decadal predictions of the North Atlantic subpolar gyre Polkova, Iuliia Swingedouw, Didier Hermanson, Leon Köhl, Armin Stammer, Detlef Smith, Doug Kröger, Jürgen Bethke, Ingo Yang, Xiaosong Zhang, Liping Nicolì, Dario Athanasiadis, Panos J. Karami, Mehdi Pasha Pankatz, Klaus Pohlmann, Holger Wu, Bo Bilbao, Roberto Ortega, Pablo Yang, Shuting Sospedra-Alfonso, Reinel Merryfield, William Kataoka, Takahito Tatebe, Hiroaki Imada, Yukiko Ishii, Masayoshi Matear, Richard J. 2023 application/pdf https://hdl.handle.net/11250/3123385 https://doi.org/10.3389/fclim.2023.1273770 eng eng Frontiers urn:issn:2624-9553 https://hdl.handle.net/11250/3123385 https://doi.org/10.3389/fclim.2023.1273770 cristin:2222220 Frontiers in Climate. 2023, 5, 1273770. Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright 2023 The Author(s) 1273770 Frontiers in Climate 5 Journal article Peer reviewed 2023 ftunivbergen https://doi.org/10.3389/fclim.2023.1273770 2024-03-27T15:07:15Z Due to large northward heat transport, the Atlantic meridional overturning circulation (AMOC) strongly affects the climate of various regions. Its internal variability has been shown to be predictable decades ahead within climate models, providing the hope that synchronizing ocean circulation with observations can improve decadal predictions, notably of the North Atlantic subpolar gyre (SPG). Climate predictions require a starting point which is a reconstruction of the past climate. This is usually performed with data assimilation methods that blend available observations and climate model states together. There is no unique method to derive the initial conditions. Moreover, this can be performed using full-field observations or their anomalies superimposed on the model's climatology to avoid strong drifts in predictions. How critical ocean circulation drifts are for prediction skill has not been assessed yet. We analyze this possible connection using the dataset of 12 decadal prediction systems from the World Meteorological Organization Lead Centre for Annual-to-Decadal Climate Prediction. We find a variety of initial AMOC errors within the predictions related to a dynamically imbalanced ocean states leading to strongly displaced or multiple maxima in the overturning structures. This likely results in a blend of what is known as model drift and initial shock. We identify that the AMOC initialization influences the quality of the SPG predictions. When predictions show a large initial error in their AMOC, they usually have low skill for predicting internal variability of the SPG for a time horizon of 6-10 years. Full-field initialized predictions with low AMOC drift show better SPG skill than those with a large AMOC drift. Nevertheless, while the anomaly-initialized predictions do not experience large drifts, they show low SPG skill when skill also present in historical runs is removed using a residual correlation metric. Thus, reducing initial shock and model biases for the ocean circulation in prediction ... Article in Journal/Newspaper North Atlantic University of Bergen: Bergen Open Research Archive (BORA-UiB) Frontiers in Climate 5 |
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Open Polar |
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University of Bergen: Bergen Open Research Archive (BORA-UiB) |
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ftunivbergen |
language |
English |
description |
Due to large northward heat transport, the Atlantic meridional overturning circulation (AMOC) strongly affects the climate of various regions. Its internal variability has been shown to be predictable decades ahead within climate models, providing the hope that synchronizing ocean circulation with observations can improve decadal predictions, notably of the North Atlantic subpolar gyre (SPG). Climate predictions require a starting point which is a reconstruction of the past climate. This is usually performed with data assimilation methods that blend available observations and climate model states together. There is no unique method to derive the initial conditions. Moreover, this can be performed using full-field observations or their anomalies superimposed on the model's climatology to avoid strong drifts in predictions. How critical ocean circulation drifts are for prediction skill has not been assessed yet. We analyze this possible connection using the dataset of 12 decadal prediction systems from the World Meteorological Organization Lead Centre for Annual-to-Decadal Climate Prediction. We find a variety of initial AMOC errors within the predictions related to a dynamically imbalanced ocean states leading to strongly displaced or multiple maxima in the overturning structures. This likely results in a blend of what is known as model drift and initial shock. We identify that the AMOC initialization influences the quality of the SPG predictions. When predictions show a large initial error in their AMOC, they usually have low skill for predicting internal variability of the SPG for a time horizon of 6-10 years. Full-field initialized predictions with low AMOC drift show better SPG skill than those with a large AMOC drift. Nevertheless, while the anomaly-initialized predictions do not experience large drifts, they show low SPG skill when skill also present in historical runs is removed using a residual correlation metric. Thus, reducing initial shock and model biases for the ocean circulation in prediction ... |
format |
Article in Journal/Newspaper |
author |
Polkova, Iuliia Swingedouw, Didier Hermanson, Leon Köhl, Armin Stammer, Detlef Smith, Doug Kröger, Jürgen Bethke, Ingo Yang, Xiaosong Zhang, Liping Nicolì, Dario Athanasiadis, Panos J. Karami, Mehdi Pasha Pankatz, Klaus Pohlmann, Holger Wu, Bo Bilbao, Roberto Ortega, Pablo Yang, Shuting Sospedra-Alfonso, Reinel Merryfield, William Kataoka, Takahito Tatebe, Hiroaki Imada, Yukiko Ishii, Masayoshi Matear, Richard J. |
spellingShingle |
Polkova, Iuliia Swingedouw, Didier Hermanson, Leon Köhl, Armin Stammer, Detlef Smith, Doug Kröger, Jürgen Bethke, Ingo Yang, Xiaosong Zhang, Liping Nicolì, Dario Athanasiadis, Panos J. Karami, Mehdi Pasha Pankatz, Klaus Pohlmann, Holger Wu, Bo Bilbao, Roberto Ortega, Pablo Yang, Shuting Sospedra-Alfonso, Reinel Merryfield, William Kataoka, Takahito Tatebe, Hiroaki Imada, Yukiko Ishii, Masayoshi Matear, Richard J. Initialization shock in the ocean circulation reduces skill in decadal predictions of the North Atlantic subpolar gyre |
author_facet |
Polkova, Iuliia Swingedouw, Didier Hermanson, Leon Köhl, Armin Stammer, Detlef Smith, Doug Kröger, Jürgen Bethke, Ingo Yang, Xiaosong Zhang, Liping Nicolì, Dario Athanasiadis, Panos J. Karami, Mehdi Pasha Pankatz, Klaus Pohlmann, Holger Wu, Bo Bilbao, Roberto Ortega, Pablo Yang, Shuting Sospedra-Alfonso, Reinel Merryfield, William Kataoka, Takahito Tatebe, Hiroaki Imada, Yukiko Ishii, Masayoshi Matear, Richard J. |
author_sort |
Polkova, Iuliia |
title |
Initialization shock in the ocean circulation reduces skill in decadal predictions of the North Atlantic subpolar gyre |
title_short |
Initialization shock in the ocean circulation reduces skill in decadal predictions of the North Atlantic subpolar gyre |
title_full |
Initialization shock in the ocean circulation reduces skill in decadal predictions of the North Atlantic subpolar gyre |
title_fullStr |
Initialization shock in the ocean circulation reduces skill in decadal predictions of the North Atlantic subpolar gyre |
title_full_unstemmed |
Initialization shock in the ocean circulation reduces skill in decadal predictions of the North Atlantic subpolar gyre |
title_sort |
initialization shock in the ocean circulation reduces skill in decadal predictions of the north atlantic subpolar gyre |
publisher |
Frontiers |
publishDate |
2023 |
url |
https://hdl.handle.net/11250/3123385 https://doi.org/10.3389/fclim.2023.1273770 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
1273770 Frontiers in Climate 5 |
op_relation |
urn:issn:2624-9553 https://hdl.handle.net/11250/3123385 https://doi.org/10.3389/fclim.2023.1273770 cristin:2222220 Frontiers in Climate. 2023, 5, 1273770. |
op_rights |
Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright 2023 The Author(s) |
op_doi |
https://doi.org/10.3389/fclim.2023.1273770 |
container_title |
Frontiers in Climate |
container_volume |
5 |
_version_ |
1796947695846293504 |