2011: Intermittent African easterly wave activity in a dry atmospheric model: Influence of the extratropics
A dynamical model is constructed of the northern summertime global circulation, maintained by empiri-cally derived forcing, based on the same dynamical code that has recently been used to study African easterly waves (AEWs) as convectively triggered perturbations (Thorncroft et al.; Leroux and Hall)...
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ftciteseerx:oai:CiteSeerX.psu:10.1.1.636.110 2023-05-15T17:33:02+02:00 2011: Intermittent African easterly wave activity in a dry atmospheric model: Influence of the extratropics Stephanie Leroux Nicholas M. J. Hall George N. Kiladis The Pennsylvania State University CiteSeerX Archives application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.636.110 http://hal-ups-tlse.archives-ouvertes.fr/docs/00/79/87/34/PDF/jcli-d-11-00049_2E1.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.636.110 http://hal-ups-tlse.archives-ouvertes.fr/docs/00/79/87/34/PDF/jcli-d-11-00049_2E1.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://hal-ups-tlse.archives-ouvertes.fr/docs/00/79/87/34/PDF/jcli-d-11-00049_2E1.pdf text ftciteseerx 2016-01-08T15:42:21Z A dynamical model is constructed of the northern summertime global circulation, maintained by empiri-cally derived forcing, based on the same dynamical code that has recently been used to study African easterly waves (AEWs) as convectively triggered perturbations (Thorncroft et al.; Leroux and Hall). In the config-uration used here, the model faithfully simulates the observed mean distributions of jets and transient dis-turbances, and explicitly represents the interactions between them. This simple GCM is used to investigate the origin and intraseasonal intermittency of AEWs in an artificially dry (no convection) context. A long integration of the model produces a summertime climatology that includes a realistic African easterly jet and westward-propagating 3–5-day disturbances over West Africa. These simulated waves display intraseasonal intermittency as the observed AEWs also do. Further experiments designed to discern the source of this intermittency in the model show that the simulated waves are mainly triggered by dynamical precursors coming from the North Atlantic storm track. The model is at least as sensitive to this remote influence as it is to local triggering by convective heating. 1. Text North Atlantic Unknown Leroux ENVELOPE(-64.231,-64.231,-65.619,-65.619) |
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ftciteseerx |
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English |
description |
A dynamical model is constructed of the northern summertime global circulation, maintained by empiri-cally derived forcing, based on the same dynamical code that has recently been used to study African easterly waves (AEWs) as convectively triggered perturbations (Thorncroft et al.; Leroux and Hall). In the config-uration used here, the model faithfully simulates the observed mean distributions of jets and transient dis-turbances, and explicitly represents the interactions between them. This simple GCM is used to investigate the origin and intraseasonal intermittency of AEWs in an artificially dry (no convection) context. A long integration of the model produces a summertime climatology that includes a realistic African easterly jet and westward-propagating 3–5-day disturbances over West Africa. These simulated waves display intraseasonal intermittency as the observed AEWs also do. Further experiments designed to discern the source of this intermittency in the model show that the simulated waves are mainly triggered by dynamical precursors coming from the North Atlantic storm track. The model is at least as sensitive to this remote influence as it is to local triggering by convective heating. 1. |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
Stephanie Leroux Nicholas M. J. Hall George N. Kiladis |
spellingShingle |
Stephanie Leroux Nicholas M. J. Hall George N. Kiladis 2011: Intermittent African easterly wave activity in a dry atmospheric model: Influence of the extratropics |
author_facet |
Stephanie Leroux Nicholas M. J. Hall George N. Kiladis |
author_sort |
Stephanie Leroux |
title |
2011: Intermittent African easterly wave activity in a dry atmospheric model: Influence of the extratropics |
title_short |
2011: Intermittent African easterly wave activity in a dry atmospheric model: Influence of the extratropics |
title_full |
2011: Intermittent African easterly wave activity in a dry atmospheric model: Influence of the extratropics |
title_fullStr |
2011: Intermittent African easterly wave activity in a dry atmospheric model: Influence of the extratropics |
title_full_unstemmed |
2011: Intermittent African easterly wave activity in a dry atmospheric model: Influence of the extratropics |
title_sort |
2011: intermittent african easterly wave activity in a dry atmospheric model: influence of the extratropics |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.636.110 http://hal-ups-tlse.archives-ouvertes.fr/docs/00/79/87/34/PDF/jcli-d-11-00049_2E1.pdf |
long_lat |
ENVELOPE(-64.231,-64.231,-65.619,-65.619) |
geographic |
Leroux |
geographic_facet |
Leroux |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
http://hal-ups-tlse.archives-ouvertes.fr/docs/00/79/87/34/PDF/jcli-d-11-00049_2E1.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.636.110 http://hal-ups-tlse.archives-ouvertes.fr/docs/00/79/87/34/PDF/jcli-d-11-00049_2E1.pdf |
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Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
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1766131388395814912 |