Smoother versus sharper Gulf Stream and Kuroshio sea surface temperature fronts: effects on cyclones and climatology
The Gulf Stream and Kuroshio regions feature strong sea surface temperature (SST) gradients that influence cyclone development and the storm track. Previous studies showed that smoothing the SSTs in either the North Atlantic or North Pacific yields a reduction in cyclone activity, surface heat fluxe...
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ftdoajarticles:oai:doaj.org/article:0759918592f043a6af269b56059ac773 2023-05-15T17:31:31+02:00 Smoother versus sharper Gulf Stream and Kuroshio sea surface temperature fronts: effects on cyclones and climatology L. Tsopouridis T. Spengler C. Spensberger 2021-10-01T00:00:00Z https://doi.org/10.5194/wcd-2-953-2021 https://doaj.org/article/0759918592f043a6af269b56059ac773 EN eng Copernicus Publications https://wcd.copernicus.org/articles/2/953/2021/wcd-2-953-2021.pdf https://doaj.org/toc/2698-4016 doi:10.5194/wcd-2-953-2021 2698-4016 https://doaj.org/article/0759918592f043a6af269b56059ac773 Weather and Climate Dynamics, Vol 2, Pp 953-970 (2021) Meteorology. Climatology QC851-999 article 2021 ftdoajarticles https://doi.org/10.5194/wcd-2-953-2021 2022-12-31T11:56:37Z The Gulf Stream and Kuroshio regions feature strong sea surface temperature (SST) gradients that influence cyclone development and the storm track. Previous studies showed that smoothing the SSTs in either the North Atlantic or North Pacific yields a reduction in cyclone activity, surface heat fluxes, and precipitation, as well as a southward shift of the storm track and the upper-level jet. To what extent these changes are attributable to changes in individual cyclone behaviour, however, remains unclear. Comparing simulations with realistic and smoothed SSTs in the atmospheric general circulation model AFES, we find that the intensification of individual cyclones in the Gulf Stream or Kuroshio region is only marginally affected by reducing the SST gradient. In contrast, we observe considerable changes in the climatological mean state as well as a reduced cyclone activity in the North Atlantic and North Pacific storm tracks that are shifted equatorward in both basins. The upper-level jet in the Atlantic also shifts equatorward, while the jet in the Pacific strengthens in its climatological position and extends further east. Surface heat fluxes, specific humidity, and precipitation also respond strongly to the smoothing of the SST, with a considerable decrease in their mean values on the warm side of the SST front. This decrease is more pronounced in the Gulf Stream than in the Kuroshio region, due to the larger decrease in SST along the Gulf Stream SST front. Considering the differences of the different variables occurring within/outside of a 750 km radius of any cyclone over their entire lifetime, we find that cyclones play only a secondary role in explaining the differences in the mean state between the smoothed and realistic SST experiments. Article in Journal/Newspaper North Atlantic Directory of Open Access Journals: DOAJ Articles Pacific Weather and Climate Dynamics 2 4 953 970 |
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Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
Meteorology. Climatology QC851-999 |
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Meteorology. Climatology QC851-999 L. Tsopouridis T. Spengler C. Spensberger Smoother versus sharper Gulf Stream and Kuroshio sea surface temperature fronts: effects on cyclones and climatology |
topic_facet |
Meteorology. Climatology QC851-999 |
description |
The Gulf Stream and Kuroshio regions feature strong sea surface temperature (SST) gradients that influence cyclone development and the storm track. Previous studies showed that smoothing the SSTs in either the North Atlantic or North Pacific yields a reduction in cyclone activity, surface heat fluxes, and precipitation, as well as a southward shift of the storm track and the upper-level jet. To what extent these changes are attributable to changes in individual cyclone behaviour, however, remains unclear. Comparing simulations with realistic and smoothed SSTs in the atmospheric general circulation model AFES, we find that the intensification of individual cyclones in the Gulf Stream or Kuroshio region is only marginally affected by reducing the SST gradient. In contrast, we observe considerable changes in the climatological mean state as well as a reduced cyclone activity in the North Atlantic and North Pacific storm tracks that are shifted equatorward in both basins. The upper-level jet in the Atlantic also shifts equatorward, while the jet in the Pacific strengthens in its climatological position and extends further east. Surface heat fluxes, specific humidity, and precipitation also respond strongly to the smoothing of the SST, with a considerable decrease in their mean values on the warm side of the SST front. This decrease is more pronounced in the Gulf Stream than in the Kuroshio region, due to the larger decrease in SST along the Gulf Stream SST front. Considering the differences of the different variables occurring within/outside of a 750 km radius of any cyclone over their entire lifetime, we find that cyclones play only a secondary role in explaining the differences in the mean state between the smoothed and realistic SST experiments. |
format |
Article in Journal/Newspaper |
author |
L. Tsopouridis T. Spengler C. Spensberger |
author_facet |
L. Tsopouridis T. Spengler C. Spensberger |
author_sort |
L. Tsopouridis |
title |
Smoother versus sharper Gulf Stream and Kuroshio sea surface temperature fronts: effects on cyclones and climatology |
title_short |
Smoother versus sharper Gulf Stream and Kuroshio sea surface temperature fronts: effects on cyclones and climatology |
title_full |
Smoother versus sharper Gulf Stream and Kuroshio sea surface temperature fronts: effects on cyclones and climatology |
title_fullStr |
Smoother versus sharper Gulf Stream and Kuroshio sea surface temperature fronts: effects on cyclones and climatology |
title_full_unstemmed |
Smoother versus sharper Gulf Stream and Kuroshio sea surface temperature fronts: effects on cyclones and climatology |
title_sort |
smoother versus sharper gulf stream and kuroshio sea surface temperature fronts: effects on cyclones and climatology |
publisher |
Copernicus Publications |
publishDate |
2021 |
url |
https://doi.org/10.5194/wcd-2-953-2021 https://doaj.org/article/0759918592f043a6af269b56059ac773 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Weather and Climate Dynamics, Vol 2, Pp 953-970 (2021) |
op_relation |
https://wcd.copernicus.org/articles/2/953/2021/wcd-2-953-2021.pdf https://doaj.org/toc/2698-4016 doi:10.5194/wcd-2-953-2021 2698-4016 https://doaj.org/article/0759918592f043a6af269b56059ac773 |
op_doi |
https://doi.org/10.5194/wcd-2-953-2021 |
container_title |
Weather and Climate Dynamics |
container_volume |
2 |
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4 |
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953 |
op_container_end_page |
970 |
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1766129158473121792 |