Journal ArticleDOI
A Case of Convection Development over the Western Mediterranean Sea: A Study through Numerical Simulations
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TLDR
In this article, a convective case producing heavy precipitation in the western Mediterranean region, characterized by pronounced upper level forcing and main rainfall over the sea, is studied, and a set of mesoscale numerical simulations using the Hirlam model is performed to investigate the mechanisms responsible for the convection development, and to assess the influence of the orography on the rainfall field.Abstract:
A convective case producing heavy precipitation in the western Mediterranean region, characterized by pronounced upper level forcing and main rainfall over the sea, is studied. On the day of the event (September 28th, 1994), more than 140 mm of precipitation were recorded in coastal lands of eastern Spain, and 180 mm were estimated over the sea with radar data. Synoptically, the case appears to combine warm and moist easterly advection at low levels, typically observed in torrential rainfall events of the region, with a less common strong upper level dynamical forcing. A set of mesoscale numerical simulations using the Hirlam model is performed to investigate the mechanisms responsible for the convection development, and to assess the influence of the orography on the rainfall field. Model output diagnosis indicates that in addition to the lower level forcing, a two-jets interaction is decisive for the triggering and driving of the convection during the event. Moreover, a non-topographic simulation reveals a relatively weak influence of the orography on this event when compared with other similar heavy precipitation cases in eastern Spain. Previous studies have shown an orographic influence of more than 90% on the rainfall whereas in this case about 50% of the precipitation over the area is attributed to the orographic forcing. The study is extended with an analysis of the individual effects of the Atlas and Iberian Peninsula, by means of a factor separation technique. It is shown that the Atlas range induces a redistribution of the precipitation over the Mediterranean, whereas local enhancements can be attributed to the Iberian topography.read more
Citations
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A numerical study of three catastrophic precipitating events over southern France. I: Numerical framework and synoptic ingredients
TL;DR: In this article, the simulation of three torrential rain events observed on 13-14 October 1995 (the Cevennes case), 12-13 November 1999 (the Aude case) and 8-9 September 2002 (the Gard case) over the southeastern part of France using the Meso-NH non-hydrostatic mesoscale numerical model was examined.
Cyclones in the Mediterranean Region: Climatology and Effects on the Environment
Piero Lionello,Jonas Bhend,Andrea Buzzi,P. M. Della-Marta,A. Jansà,Panagiotis Maheras,Antonella Sanna,Isabel F. Trigo,Ricardo M. Trigo +8 more
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Mesoscale Numerical Study of Two Cases of Long-Lived Quasi-Stationary Convective Systems over Eastern Spain
TL;DR: In this article, a set of mesoscale numerical simulations using the Pennsylvania State University-National Center for Atmospheric Research model is used to investigate two cases of extreme precipitation over eastern Spain, both of which were characterized by quasi-stationary convective systems that developed over the Valencia region and lasted more than 30 and 12 hours, respectively.
Journal ArticleDOI
A statistical downscaling to identify the large-scale circulation patterns associated with heavy precipitation events over southern France
TL;DR: In this paper, the potential for a detection algorithm to identify discriminating analysis-based statistical predictors of a few relevant parameters that can be used to capture heavy precipitation events (HPEs), or, at least, their associated large-scale circulation (LSC) patterns in a climate scenario is assessed.
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Numerical diagnosis of a small, quasi-tropical cyclone over the western Mediterranean: Dynamical vs. boundary factors
TL;DR: In this article, a sensitivity study examining the upper-level dynamic forcing, latent- and sensible-heat fluxes from the sea, and orography is conducted, and an analysis of the precise role of the upperlevel structures and the convective development is conducted.
References
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