Conditions atmosphériques des précipitations intenses dans le Bassin méditerranéen : variabilité contemporaine et future (1979-2100)
Eight wintertime extreme rainfall patterns have been computed over the whole Mediterranean basin. Extreme rainfalls are typically organized around the main sub-basin and are linked with orographic characteristics. Local atmospheric forcing of extreme rainfalls is mainly characterized by intra-Medite...
| Published in: | Méditerranée |
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| Main Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | French |
| Published: |
Presses Universitaires de Provence
2017
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| Subjects: | |
| Online Access: | https://doi.org/10.4000/mediterranee.8521 http://journals.openedition.org/mediterranee/8521 |
| Summary: | Eight wintertime extreme rainfall patterns have been computed over the whole Mediterranean basin. Extreme rainfalls are typically organized around the main sub-basin and are linked with orographic characteristics. Local atmospheric forcing of extreme rainfalls is mainly characterized by intra-Mediterranean cyclogenesis. Nevertheless, large-scale atmospheric circulation can partly explain the occurrence of some Mediterranean extreme rainfall events. For example, the frequency of “Greenland above” (“Atlantic Ridge”) weather regime explains parts of the occurrence of extreme rainfall events in the Gulf of Lions and in the Adriatic Sea (around Egerian Sea). Climate change would not change the wintertime frequency of these two weather regimes. Nevertheless, changes in mean barometric conditions within these weather regimes would increase the relationship with extreme rainfalls in the Mediterranean basin. In other words, extreme rainfalls would not become more frequent in the 21st century but events that would occurred during “Greenland above” and “Atlantic Ridge” weather regimes could become more intense. Huit configurations hivernales typiques et récurrentes de pluviométrie intense ont été extraits à l’échelle du Bassin méditerranéen. Elles montrent une structuration spatiale des pluies intenses autour des principaux reliefs et des différents sous bassins qui composent la Méditerranée. Les pluies intenses sont associées à des dépressions localisées. La dynamique atmosphérique large-échelle explique en partie la formation de ces forçages locaux des pluies intenses. En effet, la fréquence des régimes de circulation atmosphérique « Greenland Above » (« Atlantic Ridge ») explique en partie l’occurrence des pluies intense dans le golfe du Lion et l’Adriatique (autour de la mer Égée). Le changement climatique ne devrait pas modifier la fréquence de ces deux régimes de circulation. En revanche, des changements dans leur configuration barométrique moyenne devraient renforcer leur relation respective avec les pluies ... |
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