Abstract. Mediterranean catchments are regularly affected by fast and flash floods. Numerous hydrologic models have been developed, and allow modelling of these floods. However, these approaches often concern average-size basins of a few hundred km 2 . At larger scales (> 1000 km 2 ), coupling of hydrologic and hydraulic models appears to be an adapted solution. This study has as its first objective the evaluation of the performances of a coupling of models for flood hydrograph modelling. Secondly, the coupling results are compared with those of other modelling options. The aim of these comparisons is to clear up the following points. (1) Is a simplified routing model (lag and route) as efficient as a full hydraulic model for the modelling of hydrographs, in the intermediary downstream part of the stream? (2) Is adding lateral inflows necessary for all studied events? (3) What is the impact of the qualities of upstream hydrologic modelling feeding the coupling? The coupling combines the SCS-LR (Soil Conservation Service-lag-and-route) hydrologic model of the ATHYS platform and the MASCARET 1-D hydraulic model based on full Saint-Venant equations. It is applied to the Gardon River basin (2040 km 2 ) in the south of France. For the seven studied events, the results of the coupling are satisfactory, the calculated Nash indexes varying between 0.61 and 0.97. The comparisons with the other modelling options show the important role of the spatial distribution of rains during events: when rains are centered on the intermediary downstream part of the catchment, adding lateral inflows is necessary; when rains are more important in the upstream part, the quality of the hydrologic modelling upstream of the coupling has a strong impact. Furthermore, the used coupling of models seems well adapted for water rising and flooded area forecasting. The future developments of the tool will concentrate on this point.

This paper tries to evaluate morphological influence on the production of surface run-offs in natural ungauged catchments in the Mediterranean region. The goal is to analyse the type of relation between morphological descriptors of hydrological networks and catchments and their hydrological responses under rainfall episodes. Is the relation unique and stable in space and time? Is it scale dependent? Does it correspond to distinct hydrological functioning?

The phenomenon called "flashover" or "eruptive fire" in forest fires is characterized by a sudden change in fire behavior: everything seems to burst into flames instantly and firefighters are overwhelmed by a sort of eruption, spreading at a speed at far several meters per second. Unfortunately it has cost several lives in the past. The reasons for such an accident always create controversy in the research field. Different theories are highlighted and especially two major axes are currently subject to discussion because they are very popular among people involved in firefighting. The one with regard to VOCs emissions is the best-known among firemen. Under great heat, during summer or with a fire approaching, plants emit VOCs and the more the temperature grows, the more the amount of VOCs emitted grows. Under specific conditions (essentially topographical, meteorological and atmospheric), the cloud of gas can accumulate in an appropriate zone. The concentration of VOCs may therefore reach the Lower Explosive Limit, triggering the burst of the cloud when in contact with the fire. The second theory depends on physical considerations. An example is based on a convective flow created by the fire itself. When a fire spreads on a slope, it creates an aspiration phenomenon in a way to supply the fire with oxygen. The more this phenomenon is important, the more the flames tilt and increase the rate of speed, needing even more oxygen and thus induced flow. This vicious circle can stabilize or have an erratic behavior to trigger off a fire eruption. This article presents these two theories, and especially the new advances on this research subject. KeywordsFire Behavior, Flashover, Blow up, Induced Wind, VOC F.-J. Chatelon et al. 548

The flash flood forecasting is one of the most important challenges for research in hydrology. The anticipation of extreme hydrological scenarios through rainfall-runoff models is still limited, mainly because of the high uncertainty of rainfall forecasts, as of limited computing resources. The authors propose to simulate an ensemble of potential hydrological scenarios in order to support the forecaster's decision-making process. The developed applicative layer takes advantage of the computing capabilities of Grid technology, significantly enhancing the management of independent modelling operations in an operational lead time. A set of experimentations is deployed in order to firstly assess efficiency of this applicative layer and secondly to gauge more broadly the potentialities of Grid to handle flood crisis management operations. Finally, in managing more than one hundred hydrological simulations simultaneously, this experimental platform opens new perspectives for the improvement of hydrological forecast modelling, limited up to now by the lack of computing resources.

Indexes of forest fire risk are broadcast throughout the Summer months by the French Civil Defense Authority. They are used to guide the deployment of fire prevention resources. However, in some departments, the number of fires during the Winter and Spring months of March–April is equal to or greater than during the Summer months. Some days, conditions are favourable for the propagation of fire (soil moisture content, vegetation in dormancy, relative humidity, ...), but indexes for estimating the risk during this period are not calculated. The objective of this paper is to evaluate various models of fire rate of spread, in order to choose one for Winter and Spring fires. The Fire Service of a department of the French Mediterranean area (the Lozère department) provides the opportunity and the means to conduct validation experiments on prescribed fires. Also, validation data from another department of the French Mediterranean area (Pyrénées Orientales) are presented for the same rate of spread models.

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Emergency operations are on the rise today due to the different types of emergencies encountered, which include crises, accidents, natural disasters, and suicides. This increase can lead to problems in coordination and communication between those involved in an emergency operation. In addition, emergency services have independent medical devices, which are sometimes redundant; however, there is a lack of devices for taking suitable actions in heterogeneous environments (urban, rural, mountains). Therefore, it would be interesting to redesign ambulance services to take account of these issues. These improvements concern two objectives. First, to provide an optimal response to the victim during an emergency operation. Second, to facilitate the exchanges between all people involved from the initial order to the arrival at the hospital. This paper focuses on and illustrates a solution to simplify exchanges between first-aid workers in the field and medical practitioners in the hospital during emergency operations. In particular, it analyzes interoperability at the outset of the conception of a system that helps to exchange quickly and efficiently information for a medical emergency.

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