Bidimensional Diagnostics, Variability, and Trends of Northern Hemisphere Blocking
AbstractIn this paper, Northern Hemisphere winter blocking is analyzed through the introduction of a set of new bidimensional diagnostics based on geopotential height that provide information about the occurrence, the duration, the intensity, and the wave breaking associated with the blocking. This...
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ftopenaccessrep:oai:zenodo.org:106973 2023-10-25T01:39:10+02:00 Bidimensional Diagnostics, Variability, and Trends of Northern Hemisphere Blocking Chiara Cagnazzo Antonio Navarra Paolo Davini Silvio Gualdi 2012-04-05 https://www.openaccessrepository.it/record/106973 https://doi.org/10.1175/jcli-d-12-00032.1 eng eng info:eu-repo/grantAgreement/EC/FP7/226520/ url:https://www.openaccessrepository.it/communities/itmirror https://www.openaccessrepository.it/record/106973 doi:10.1175/jcli-d-12-00032.1 info:eu-repo/semantics/openAccess SP1-Cooperation EC FP7 European Commission Environment (including Climate Change) EUTOPIA Alliance NEANIAS Atmospheric Research Community Atmospheric Science info:eu-repo/semantics/article publication-article 2012 ftopenaccessrep https://doi.org/10.1175/jcli-d-12-00032.1 2023-09-26T22:22:06Z AbstractIn this paper, Northern Hemisphere winter blocking is analyzed through the introduction of a set of new bidimensional diagnostics based on geopotential height that provide information about the occurrence, the duration, the intensity, and the wave breaking associated with the blocking. This analysis is performed with different reanalysis datasets in order to evaluate the sensitivity of the index and the diagnostics adopted. In this way, the authors are able to define a new category of blocking placed at low latitudes that is similar to midlatitude blocking in terms of the introduced diagnostics but is unable to divert or block the flow. Furthermore, over the Euro-Atlantic sector it is shown that it is possible to phenomenologically distinguish between high-latitude blocking occurring over Greenland, north of the jet stream and dominated by cyclonic wave breaking, and the traditional midlatitude blocking localized over Europe and driven by anticyclonic wave breaking. These latter events are uniformly present in a band ranging from the Azores up to Scandinavia. Interestingly, a similar distinction cannot be pointed out over the Pacific basin where the blocking activity is dominated by high-latitude blocking occurring over eastern Siberia. Finally, considering the large impact that blocking may have on the Northern Hemisphere, an analysis of the variability and the trend is carried out. This shows a significant increase of Atlantic low-latitude blocking frequency and an eastward displacement of the strongest blocking events over both the Atlantic and Pacific Oceans. Article in Journal/Newspaper Greenland Siberia Istituto Nazionale di Fisica Nucleare (INFN): Open Access Repository Greenland Pacific Journal of Climate 25 19 6496 6509 |
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Open Polar |
collection |
Istituto Nazionale di Fisica Nucleare (INFN): Open Access Repository |
op_collection_id |
ftopenaccessrep |
language |
English |
topic |
SP1-Cooperation EC FP7 European Commission Environment (including Climate Change) EUTOPIA Alliance NEANIAS Atmospheric Research Community Atmospheric Science |
spellingShingle |
SP1-Cooperation EC FP7 European Commission Environment (including Climate Change) EUTOPIA Alliance NEANIAS Atmospheric Research Community Atmospheric Science Chiara Cagnazzo Antonio Navarra Paolo Davini Silvio Gualdi Bidimensional Diagnostics, Variability, and Trends of Northern Hemisphere Blocking |
topic_facet |
SP1-Cooperation EC FP7 European Commission Environment (including Climate Change) EUTOPIA Alliance NEANIAS Atmospheric Research Community Atmospheric Science |
description |
AbstractIn this paper, Northern Hemisphere winter blocking is analyzed through the introduction of a set of new bidimensional diagnostics based on geopotential height that provide information about the occurrence, the duration, the intensity, and the wave breaking associated with the blocking. This analysis is performed with different reanalysis datasets in order to evaluate the sensitivity of the index and the diagnostics adopted. In this way, the authors are able to define a new category of blocking placed at low latitudes that is similar to midlatitude blocking in terms of the introduced diagnostics but is unable to divert or block the flow. Furthermore, over the Euro-Atlantic sector it is shown that it is possible to phenomenologically distinguish between high-latitude blocking occurring over Greenland, north of the jet stream and dominated by cyclonic wave breaking, and the traditional midlatitude blocking localized over Europe and driven by anticyclonic wave breaking. These latter events are uniformly present in a band ranging from the Azores up to Scandinavia. Interestingly, a similar distinction cannot be pointed out over the Pacific basin where the blocking activity is dominated by high-latitude blocking occurring over eastern Siberia. Finally, considering the large impact that blocking may have on the Northern Hemisphere, an analysis of the variability and the trend is carried out. This shows a significant increase of Atlantic low-latitude blocking frequency and an eastward displacement of the strongest blocking events over both the Atlantic and Pacific Oceans. |
format |
Article in Journal/Newspaper |
author |
Chiara Cagnazzo Antonio Navarra Paolo Davini Silvio Gualdi |
author_facet |
Chiara Cagnazzo Antonio Navarra Paolo Davini Silvio Gualdi |
author_sort |
Chiara Cagnazzo |
title |
Bidimensional Diagnostics, Variability, and Trends of Northern Hemisphere Blocking |
title_short |
Bidimensional Diagnostics, Variability, and Trends of Northern Hemisphere Blocking |
title_full |
Bidimensional Diagnostics, Variability, and Trends of Northern Hemisphere Blocking |
title_fullStr |
Bidimensional Diagnostics, Variability, and Trends of Northern Hemisphere Blocking |
title_full_unstemmed |
Bidimensional Diagnostics, Variability, and Trends of Northern Hemisphere Blocking |
title_sort |
bidimensional diagnostics, variability, and trends of northern hemisphere blocking |
publishDate |
2012 |
url |
https://www.openaccessrepository.it/record/106973 https://doi.org/10.1175/jcli-d-12-00032.1 |
geographic |
Greenland Pacific |
geographic_facet |
Greenland Pacific |
genre |
Greenland Siberia |
genre_facet |
Greenland Siberia |
op_relation |
info:eu-repo/grantAgreement/EC/FP7/226520/ url:https://www.openaccessrepository.it/communities/itmirror https://www.openaccessrepository.it/record/106973 doi:10.1175/jcli-d-12-00032.1 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1175/jcli-d-12-00032.1 |
container_title |
Journal of Climate |
container_volume |
25 |
container_issue |
19 |
container_start_page |
6496 |
op_container_end_page |
6509 |
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1780734344278573056 |