Improvement in the decadal prediction skill of the North Atlantic extratropical winter circulation through increased model resolution
In this study the latest version of the MiKlip decadal hindcast system is analyzed, and the effect of an increased horizontal and vertical resolution on the prediction skill of the extratropical winter circulation is assessed. Four different metrics – the storm track, blocking, cyclone and windstorm...
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ftfuberlin:oai:refubium.fu-berlin.de:fub188/26316 2023-05-15T17:25:20+02:00 Improvement in the decadal prediction skill of the North Atlantic extratropical winter circulation through increased model resolution Schuster, Mareike Grieger, Jens Richling, Andy Schartner, Thomas Illing, Sebastian Kadow, Christopher Müller, Wolfgang A. Pohlmann, Holger Pfahl, Stephan Ulbrich, Uwe 2019 17 Seiten application/pdf https://refubium.fu-berlin.de/handle/fub188/26316 https://doi.org/10.17169/refubium-26075 https://doi.org/10.5194/esd-10-901-2019 eng eng https://refubium.fu-berlin.de/handle/fub188/26316 http://dx.doi.org/10.17169/refubium-26075 doi:10.5194/esd-10-901-2019 https://creativecommons.org/licenses/by/4.0/ CC-BY North Atlantic extratropical winter circulation decadal prediction ddc:551 doc-type:article 2019 ftfuberlin https://doi.org/10.17169/refubium-26075 https://doi.org/10.5194/esd-10-901-2019 2022-05-15T20:45:22Z In this study the latest version of the MiKlip decadal hindcast system is analyzed, and the effect of an increased horizontal and vertical resolution on the prediction skill of the extratropical winter circulation is assessed. Four different metrics – the storm track, blocking, cyclone and windstorm frequencies – are analyzed in the North Atlantic and European region. The model bias and the deterministic decadal hindcast skill are evaluated in ensembles of five members in a lower-resolution version (LR, atm: T63L47, ocean: 1.5∘ L40) and a higher-resolution version (HR, atm: T127L95, ocean: 0.4∘ L40) of the MiKlip system based on the Max Planck Institute Earth System model (MPI-ESM). The skill is assessed for the lead winters 2–5 in terms of the anomaly correlation of the quantities' winter averages using initializations between 1978 and 2012. The deterministic predictions are considered skillful if the anomaly correlation is positive and statistically significant. While the LR version shows common shortcomings of lower-resolution climate models, e.g., a storm track that is too zonal and southward displaced as well as a negative bias of blocking frequencies over the eastern North Atlantic and Europe, the HR version counteracts these biases. Cyclones, i.e., their frequencies and characteristics like strength and lifetime, are particularly better represented in HR. As a result, a chain of significantly improved decadal prediction skill between all four metrics is found with the increase in the spatial resolution. While the skill of the storm track is significantly improved primarily over the main source region of synoptic activity – the North Atlantic Current – the other extratropical quantities experience a significant improvement primarily downstream thereof, i.e., in regions where the synoptic systems typically intensify. Thus, the skill of the cyclone frequencies is significantly improved over the central North Atlantic and northern Europe, the skill of the blocking frequencies is significantly improved over ... Article in Journal/Newspaper north atlantic current North Atlantic Freie Universität Berlin: Refubium (FU Berlin) |
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Open Polar |
collection |
Freie Universität Berlin: Refubium (FU Berlin) |
op_collection_id |
ftfuberlin |
language |
English |
topic |
North Atlantic extratropical winter circulation decadal prediction ddc:551 |
spellingShingle |
North Atlantic extratropical winter circulation decadal prediction ddc:551 Schuster, Mareike Grieger, Jens Richling, Andy Schartner, Thomas Illing, Sebastian Kadow, Christopher Müller, Wolfgang A. Pohlmann, Holger Pfahl, Stephan Ulbrich, Uwe Improvement in the decadal prediction skill of the North Atlantic extratropical winter circulation through increased model resolution |
topic_facet |
North Atlantic extratropical winter circulation decadal prediction ddc:551 |
description |
In this study the latest version of the MiKlip decadal hindcast system is analyzed, and the effect of an increased horizontal and vertical resolution on the prediction skill of the extratropical winter circulation is assessed. Four different metrics – the storm track, blocking, cyclone and windstorm frequencies – are analyzed in the North Atlantic and European region. The model bias and the deterministic decadal hindcast skill are evaluated in ensembles of five members in a lower-resolution version (LR, atm: T63L47, ocean: 1.5∘ L40) and a higher-resolution version (HR, atm: T127L95, ocean: 0.4∘ L40) of the MiKlip system based on the Max Planck Institute Earth System model (MPI-ESM). The skill is assessed for the lead winters 2–5 in terms of the anomaly correlation of the quantities' winter averages using initializations between 1978 and 2012. The deterministic predictions are considered skillful if the anomaly correlation is positive and statistically significant. While the LR version shows common shortcomings of lower-resolution climate models, e.g., a storm track that is too zonal and southward displaced as well as a negative bias of blocking frequencies over the eastern North Atlantic and Europe, the HR version counteracts these biases. Cyclones, i.e., their frequencies and characteristics like strength and lifetime, are particularly better represented in HR. As a result, a chain of significantly improved decadal prediction skill between all four metrics is found with the increase in the spatial resolution. While the skill of the storm track is significantly improved primarily over the main source region of synoptic activity – the North Atlantic Current – the other extratropical quantities experience a significant improvement primarily downstream thereof, i.e., in regions where the synoptic systems typically intensify. Thus, the skill of the cyclone frequencies is significantly improved over the central North Atlantic and northern Europe, the skill of the blocking frequencies is significantly improved over ... |
format |
Article in Journal/Newspaper |
author |
Schuster, Mareike Grieger, Jens Richling, Andy Schartner, Thomas Illing, Sebastian Kadow, Christopher Müller, Wolfgang A. Pohlmann, Holger Pfahl, Stephan Ulbrich, Uwe |
author_facet |
Schuster, Mareike Grieger, Jens Richling, Andy Schartner, Thomas Illing, Sebastian Kadow, Christopher Müller, Wolfgang A. Pohlmann, Holger Pfahl, Stephan Ulbrich, Uwe |
author_sort |
Schuster, Mareike |
title |
Improvement in the decadal prediction skill of the North Atlantic extratropical winter circulation through increased model resolution |
title_short |
Improvement in the decadal prediction skill of the North Atlantic extratropical winter circulation through increased model resolution |
title_full |
Improvement in the decadal prediction skill of the North Atlantic extratropical winter circulation through increased model resolution |
title_fullStr |
Improvement in the decadal prediction skill of the North Atlantic extratropical winter circulation through increased model resolution |
title_full_unstemmed |
Improvement in the decadal prediction skill of the North Atlantic extratropical winter circulation through increased model resolution |
title_sort |
improvement in the decadal prediction skill of the north atlantic extratropical winter circulation through increased model resolution |
publishDate |
2019 |
url |
https://refubium.fu-berlin.de/handle/fub188/26316 https://doi.org/10.17169/refubium-26075 https://doi.org/10.5194/esd-10-901-2019 |
genre |
north atlantic current North Atlantic |
genre_facet |
north atlantic current North Atlantic |
op_relation |
https://refubium.fu-berlin.de/handle/fub188/26316 http://dx.doi.org/10.17169/refubium-26075 doi:10.5194/esd-10-901-2019 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.17169/refubium-26075 https://doi.org/10.5194/esd-10-901-2019 |
_version_ |
1766116738673410048 |