Mise en oeuvre d'un outil d'alerte et de cartographie temps réel des aléas naturels liés aux précipitations dans les régions montagneuses et méditerranéennes du Sud-Est de la France

International audienceDue to its mountainous topography and its Mediterranean climate, the Provence-Alpes-Côte d'Azur (PACA) region in Southeastern France is particularly prone to flash floods, debris flows and mass movements (landslides and rockfall). A mapping system for these rainfall induced hazards has been tested by local and regional authorities and Government agencies since 2011 as part of the RHYTMME project. This system allows, thank to radar rainfall estimation and rainfall-runoff modelling, the real-time warning and monitoring of flash floods wherever they may occur in the PACA territory. It is also intended to enable, during intense rainfall events, the localisation of the streams susceptible to generate debris flows and of the slopes the more likely to trigger landslides and/or rockfalls

Using damage reports to assess different versions of a hydrological early warning system

International audienceIn Europe, flash floods affect mainly the Mediterranean and mountainous regions, even if other regions also occasionally suffer from them. The catchments involved are usually small and ungauged, with short time of concentration. Forecasting this type of event remains difficult using hydrological models, and assessing the models 5 is even more problematic. Typically, assessment is limited to gauged catchments that have relatively different geomorphological characteristics. The aim of this article is to present a method for assessing the models on real ungauged catchments through the use of damage reports and a multi-threshold approach, with assessment criteria that are based on a contingency table of the Critical Success Index type. The main 10 conclusion, as demonstrated by Irstea's " Adaptation d'Information géographique pour l'Alerte en crue " for " Geographic information adaptation for flood warning " (AIGA) flood forecasting system and by the new version of AIGA for high-altitude catchments, is that while assessing hydrological models on gauged catchments is necessary, it is never sufficient and must be supplemented by assessments on ungauged catchments. This 15 underlines the utility of building flood damage databases that are as exhaustive as possible. Such databases can be a valuable addition to more standard, often limited sources of data, especially for mountainous regions

Federation of internet of things testbeds for the realization of a semantically-enabled multi-domain data marketplace

The Internet of Things (IoT) concept has attracted a lot of attention from the research and innovation community for a number of years already. One of the key drivers for this hype towards the IoT is its applicability to a plethora of different application domains. However, infrastructures enabling experimental assessment of IoT solutions are scarce. Being able to test and assess the behavior and the performance of any piece of technology (i.e., protocol, algorithm, application, service, etc.) under real-world circumstances is of utmost importance to increase the acceptance and reduce the time to market of these innovative developments. This paper describes the federation of eleven IoT deployments from heterogeneous application domains (e.g., smart cities, maritime, smart building, crowd-sensing, smart grid, etc.) with over 10,000 IoT devices overall which produce hundreds of thousands of observations per day. The paper summarizes the resources that are made available through a cloud-based platform. The main contributions from this paper are twofold. In the one hand, the insightful summary of the federated data resources are relevant to the experimenters that might be seeking for an experimental infrastructure to assess their innovations. On the other hand, the identification of the challenges met during the testbed integration process, as well as the mitigation strategies that have been implemented to face them, are of interest for testbed providers that can be considering to join the federation. © 2018 by the authors. Licensee MDPI, Basel, Switzerland

Federation of internet of things testbeds for the realization of a semantically-enabled multi-domain data marketplace

The Internet of Things (IoT) concept has attracted a lot of attention from the research and innovation community for a number of years already. One of the key drivers for this hype towards the IoT is its applicability to a plethora of different application domains. However, infrastructures enabling experimental assessment of IoT solutions are scarce. Being able to test and assess the behavior and the performance of any piece of technology (i.e., protocol, algorithm, application, service, etc.) under real-world circumstances is of utmost importance to increase the acceptance and reduce the time to market of these innovative developments. This paper describes the federation of eleven IoT deployments from heterogeneous application domains (e.g., smart cities, maritime, smart building, crowd-sensing, smart grid, etc.) with over 10,000 IoT devices overall which produce hundreds of thousands of observations per day. The paper summarizes the resources that are made available through a cloud-based platform. The main contributions from this paper are twofold. In the one hand, the insightful summary of the federated data resources are relevant to the experimenters that might be seeking for an experimental infrastructure to assess their innovations. On the other hand, the identification of the challenges met during the testbed integration process, as well as the mitigation strategies that have been implemented to face them, are of interest for testbed providers that can be considering to join the federation

Hydrological post event survey after the autumn 2014 floods in the Cévennes region in France: results and first hydrological analyses

International audienceDuring the autumn 2014, an exceptional succession of intense rain events and associated flash floods have hit a large territory extending from the Hérault to the Gard and Ardèche regions in south east of France. These events caused 17 casualties and estimated damages ranging from 550 to 600 billion euros (FFSA). On several upstream watersheds, the reported floods seem to be the largest observed from human memory, and may therefore become reference events for flood risk prevention. A post event survey was organised within the Hymex framework in order to document the first 3 events which occurred successively from the 15th of September to the 15th of October. A total of 64 peak discharge values were estimated, enabling a detailed description of observed hydrological reactions. The analysis of this dataset confirms the very significant peak discharge levels, which remain however significantly below the envelope curves and the discharge values observed during some other historical events in this region (for instance the 2002 flood). A detailed hydrological analysis of this dataset based on rainfall runoff simulations is now in progress. It is worth noting that some of the affected areas were already hit by the 2002 and 2008 events, for which post event surveys were already conducted: therefore, a comparison of the hydrological reactions for these three events will be possible. The proposed communication will include the presentation of the characteristics and consequences of the main flood events, the dataset obtained from the post event survey, and the first lessons derived from the hydrological analysis