The catastrophic flash-flood event of 8-9 September 2002 in the Gard region, France:: A first case study for the Cevennes-Vivarais Mediterranean Hydrometeorological Observatory
The catastrophic flash-flood event of 8-9 September 2002 in the Gard region, France:: A first case study for the Cevennes-Vivarais Mediterranean Hydrometeorological Observatory
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DOI：
10.1175/jhm-400.1
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发表时间：
2005-02-01
影响因子：
3.8
通讯作者：
Wobrock, W
中科院分区：
文献类型：
--
作者：
Delrieu, G;Ducrocq, V;Wobrock, W
Cevennes-Vivarais Mediterranean Hydrometeorological Observatory（OHM-CV）是一项研究计划，旨在提高对地中海强降雨事件的理解和建模，这些事件经常导致法国南部发生毁灭性的山洪暴发。一个主要目标是汇集气象学家和水文学家、模型制作者和仪器制作者、研究人员和从业人员的技能，以科普这些相当不可预测的事件。根据以前出版的山洪专题论文，本文件旨在记录2002年9月8日至9日的灾难性事件，该事件造成24人伤亡，经济损失估计为12亿欧元（即，在法国的加尔地区，这一计划耗资约70亿美元。首先给出了天气气象形势的描述，表明没有特定的前兆表明这种极端事件的临近。然后，雷达和雨量计分析被用来评估降雨事件的大小，这是特别显着的空间范围内的降雨量大于200毫米，在24小时超过5500公里（2）。当地观测到的最大值为600-700毫米，是该地区最高的日记录之一。事件后水文调查的初步结果表明，Gard和Vidourle河上游流域的水文响应与降雨事件的显着时空结构是一致的。值得注意的是，在大多数受影响地区，峰值比流量非常高（5-10 m（3）s（-1）km（-2）），并达到超过20 m（3）s（-1）km（-2）的局部异常值。初步分析表明，对比水文行为，似乎与地貌因素，特别是在该地区的部分岩溶的影响。概述了正在进行的气象和水文研究项目，致力于这种情况下的OHM-CV研究的最后。
The Cevennes-Vivarais Mediterranean Hydrometeorological Observatory (OHM-CV) is a research initiative aimed at improving the understanding and modeling of the Mediterranean intense rain events that frequently result in devastating flash floods in southern France. A primary objective is to bring together the skills of meteorologists and hydrologists, modelers and instrumentalists, researchers and practitioners, to cope with these rather unpredictable events. In line with previously published flash-flood monographs, the present paper aims at documenting the 8-9 September 2002 catastrophic event, which resulted in 24 casualties and an economic damage evaluated at 1.2 billion euros (i.e., about 7 billion U.S. dollars) in the Gard region, France. A description of the synoptic meteorological situation is first given and shows that no particular precursor indicated the imminence of such an extreme event. Then, radar and rain gauge analyses are used to assess the magnitude of the rain event, which was particularly remarkable for its spatial extent with rain amounts greater than 200 mm in 24 h over 5500 km(2). The maximum values of 600-700 mm observed locally are among the highest daily records in the region. The preliminary results of the postevent hydrological investigation show that the hydrologic response of the upstream watersheds of the Gard and Vidourle Rivers is consistent with the marked space-time structure of the rain event. It is noteworthy that peak specific discharges were very high over most of the affected areas (5-10 m(3) s(-1) km(-2)) and reached locally extraordinary values of more than 20 m(3) s(-1) km(-2). A preliminary analysis indicates contrasting hydrological behaviors that seem to be related to geomorphological factors, notably the influence of karst in part of the region. An overview of the ongoing meteorological and hydrological research projects devoted to this case study within the OHM-CV is finally presented.