La distribution spatiale des précipitations et son rôle dans la transformation pluie-débit

Additional results concerning the spatial distribution of rainfall and its role in the transformation of rain-flowrate

Institut de mécanique, ENSHMG-INPG, Grenoble

Abstract

In this preliminary study, the calculation of time pitch isohyet surfaces are firstly recalled and then its sensitivity as regards the uncertainty of localization of stations, which is finally not critical in normal conditions, is analysed. Then the emphasis is placed on the importance of being fully familiar with rainfall spatial distribution so as identify the individual responses of sub-basins by selecting the irregular intervals when they have been excited in various ways by the input of rain. To conclude, the emphasis is placed on the size, even with average rainfall, between highly concentrated isohyets, or rather distributed, on the discharge response. These somewhat original observations, obtained in the Gardon d'Anduze (500 km²), are currently being modelized.