Mean kinematic characteristics of synoptic easterly disturbances over the Atlantic
International audience This study investigates the mean kinematic characteristics of the tropical Atlantic easterly disturbances in January–March (JFM), April–June (AMJ), July–September (JAS) and October–December (OND) from 1968–1998. For each season, the preferential tracks of these disturbances in...
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ftinsu:oai:HAL:insu-00412021v1 2024-04-28T08:31:10+00:00 Mean kinematic characteristics of synoptic easterly disturbances over the Atlantic Diedhiou, Arona Machado, Luiz A. T. Laurent, Henri Laboratoire d'étude des transferts en hydrologie et environnement (LTHE) Observatoire des Sciences de l'Univers de Grenoble (OSUG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS) Center for Weather Forecasting and Climate Studies São Paulo (CPTEC) Instituto Nacional de Pesquisas Espaciais (INPE) the CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, Brazil) / IRD (Institut de Recherche pour le Développement, France) cooperative project (Grant No. 910153/98-1); the FAPESP (Fundaçao de Amparo à Pesquisa do Estado de Sao Paulo) (Grant No.99/06045) 2010 https://insu.hal.science/insu-00412021 https://doi.org/10.1007/s00376-009-9092-5 en eng HAL CCSD Springer Verlag info:eu-repo/semantics/altIdentifier/doi/10.1007/s00376-009-9092-5 insu-00412021 https://insu.hal.science/insu-00412021 doi:10.1007/s00376-009-9092-5 ISSN: 0256-1530 EISSN: 1861-9533 Advances in Atmospheric Sciences https://insu.hal.science/insu-00412021 Advances in Atmospheric Sciences, 2010, 27 (3), pp.483-499. ⟨10.1007/s00376-009-9092-5⟩ synoptic activity African easterly waves tropical Atlantic info:eu-repo/semantics/article Journal articles 2010 ftinsu https://doi.org/10.1007/s00376-009-9092-5 2024-04-05T00:29:02Z International audience This study investigates the mean kinematic characteristics of the tropical Atlantic easterly disturbances in January–March (JFM), April–June (AMJ), July–September (JAS) and October–December (OND) from 1968–1998. For each season, the preferential tracks of these disturbances in the 3–10-day band periods were computed and spatialized, as well as their associated wavelength, velocity and main period, which lies between 3–5 days and between 6–9 days depending on the track and the season. Two main tracks are highlighted over the Atlantic Ocean. During OND and JFM these two tracks are well separated and located in each hemisphere around 15°S and 12.5°N. From AMJ to JAS these tracks migrate northward; in JAS, they merge into one over the northern tropical Atlantic along 17.5°N. The associated wavelength fields exhibit a meridional gradient, with large wavelengths (greater than 4000 km) around the equator, between 5°N and 5°S, and smaller wavelengths outside of this latitude band (between 2500–3500 km). The phase speed is also found to exhibit poleward decreasing values from 12–6 m s−1. Over the north Atlantic track, 6–9-day disturbances were found to occur from January to May and approximately from October to December. From June to September, the 3–5-day waves dominate the synoptic activity. Over the south Atlantic track, between May and August the synoptic variability is mainly explained by the 3–5-day disturbances but from January to April and from September to December both 3–5-day waves and 6–9-day waves can occur. Article in Journal/Newspaper North Atlantic Institut national des sciences de l'Univers: HAL-INSU Advances in Atmospheric Sciences 27 3 483 499 |
institution |
Open Polar |
collection |
Institut national des sciences de l'Univers: HAL-INSU |
op_collection_id |
ftinsu |
language |
English |
topic |
synoptic activity African easterly waves tropical Atlantic |
spellingShingle |
synoptic activity African easterly waves tropical Atlantic Diedhiou, Arona Machado, Luiz A. T. Laurent, Henri Mean kinematic characteristics of synoptic easterly disturbances over the Atlantic |
topic_facet |
synoptic activity African easterly waves tropical Atlantic |
description |
International audience This study investigates the mean kinematic characteristics of the tropical Atlantic easterly disturbances in January–March (JFM), April–June (AMJ), July–September (JAS) and October–December (OND) from 1968–1998. For each season, the preferential tracks of these disturbances in the 3–10-day band periods were computed and spatialized, as well as their associated wavelength, velocity and main period, which lies between 3–5 days and between 6–9 days depending on the track and the season. Two main tracks are highlighted over the Atlantic Ocean. During OND and JFM these two tracks are well separated and located in each hemisphere around 15°S and 12.5°N. From AMJ to JAS these tracks migrate northward; in JAS, they merge into one over the northern tropical Atlantic along 17.5°N. The associated wavelength fields exhibit a meridional gradient, with large wavelengths (greater than 4000 km) around the equator, between 5°N and 5°S, and smaller wavelengths outside of this latitude band (between 2500–3500 km). The phase speed is also found to exhibit poleward decreasing values from 12–6 m s−1. Over the north Atlantic track, 6–9-day disturbances were found to occur from January to May and approximately from October to December. From June to September, the 3–5-day waves dominate the synoptic activity. Over the south Atlantic track, between May and August the synoptic variability is mainly explained by the 3–5-day disturbances but from January to April and from September to December both 3–5-day waves and 6–9-day waves can occur. |
author2 |
Laboratoire d'étude des transferts en hydrologie et environnement (LTHE) Observatoire des Sciences de l'Univers de Grenoble (OSUG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS) Center for Weather Forecasting and Climate Studies São Paulo (CPTEC) Instituto Nacional de Pesquisas Espaciais (INPE) the CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, Brazil) / IRD (Institut de Recherche pour le Développement, France) cooperative project (Grant No. 910153/98-1); the FAPESP (Fundaçao de Amparo à Pesquisa do Estado de Sao Paulo) (Grant No.99/06045) |
format |
Article in Journal/Newspaper |
author |
Diedhiou, Arona Machado, Luiz A. T. Laurent, Henri |
author_facet |
Diedhiou, Arona Machado, Luiz A. T. Laurent, Henri |
author_sort |
Diedhiou, Arona |
title |
Mean kinematic characteristics of synoptic easterly disturbances over the Atlantic |
title_short |
Mean kinematic characteristics of synoptic easterly disturbances over the Atlantic |
title_full |
Mean kinematic characteristics of synoptic easterly disturbances over the Atlantic |
title_fullStr |
Mean kinematic characteristics of synoptic easterly disturbances over the Atlantic |
title_full_unstemmed |
Mean kinematic characteristics of synoptic easterly disturbances over the Atlantic |
title_sort |
mean kinematic characteristics of synoptic easterly disturbances over the atlantic |
publisher |
HAL CCSD |
publishDate |
2010 |
url |
https://insu.hal.science/insu-00412021 https://doi.org/10.1007/s00376-009-9092-5 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
ISSN: 0256-1530 EISSN: 1861-9533 Advances in Atmospheric Sciences https://insu.hal.science/insu-00412021 Advances in Atmospheric Sciences, 2010, 27 (3), pp.483-499. ⟨10.1007/s00376-009-9092-5⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1007/s00376-009-9092-5 insu-00412021 https://insu.hal.science/insu-00412021 doi:10.1007/s00376-009-9092-5 |
op_doi |
https://doi.org/10.1007/s00376-009-9092-5 |
container_title |
Advances in Atmospheric Sciences |
container_volume |
27 |
container_issue |
3 |
container_start_page |
483 |
op_container_end_page |
499 |
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1797588777963618304 |