RExHySS Impact du changement climatique sur les Ressources en Eau et les Extrêmes Hydrologiques dans les bassins de la Seine et la Somme
	Accueil Description    Résumé français    Résumé anglais    Justification    Objectifs    Sites retenus    Partenaires    Work packages    Programme de travail    Valorisation    Références citées Réunions Documents Intranet Liens utiles		Description > Résumé anglais
			The aim of this project is to assess the impact of climate change on extreme hydrological events in the river basins of the Seine and Somme (France). We will benefit from recent advances in the statistical downscaling of climate simulations. A weather regime approach and a variable correction approach will allow us to account for changes in climate variability at daily to inter-annual time scales, in addition to mean climate change considered in previous studies. We will characterize how climate change is susceptible to impact the distribution of extreme events, regarding high and low flows and droughts, using classical frequency analyses. The input are the discharge, soil moisture and piezometric heads simulated by a set of state-of-the-art hydrological models. We will also focus on some manifestations of these extremes to which societies are particularly sensitive. Regarding floods, we will assess the changes in their extension in some key areas of the two basins (Somme valley upstream from Abbeville, Seine valley including Paris and the alluvial plain of the Bassée) and for selected return periods. We will also consider the relationships between agriculture and the river system, with respect to irrigation demand and its impact on water resources, crop production and nitrate pollution, which can be simulated by the coupled model STICS-MODCOU. When assessing how these processes and their feed-backs may be modified under climate change, we will distinguish the impact of mean climate vs. climate variability. The last part of this project addresses the feed-backs between the changes in rivers systems and social systems. We will communicate our results to the actors of water management in the two studied watersheds. The form of results will be defined with these actors to be suited to a socio-economic assessment of the simulated changes in extreme hydrological events. Among the sensitive questions, one can find urban storm water effluents o rthe impacts of floods on infrastructures, transportation or energy production. This kind of analysis, although qualitative, is important to support adaptation strategies to climate change, but the elaboration of such strategies is not in the scope of this project.
	Contactez le Webmaster		Mis à jour le 13/01/09