Vieux R.E. auteur aut IRD Looper J.P. auteur aut IRD Cappelaere Bernard auteur aut IRD Peugeot Christophe auteur aut IRD Maia A. auteur aut IRD text bookSection eng text/pdf reformatted digital access Drought persisting in the Sahel for more than 25 years, impacting both surface and subsurface water resources, raises the question whether the hydrological impacts are proportional, dampened, or amplified in response to the climatic change manifested by the drought experienced since 1970. A physically-based distributed model, r.water.fea, applied to a 2.48 km2 endoreic drainage basin, typical of the Niamey area of West Niger, is used to evaluate the sensitivity of the hydrological system to such climatic extremes under four reduced-rainfall scenarios. Scenarios are built by elimination of various subsets of recorded storm events from the four monitored seasons 1992-1995. The hydrological response varies from no decrease to nearly a 30% decrease depending on the storm selection criteria. These results emphasize the variability of the hydrological response to regional climatic changes and the importance of a detailed characterization of the hydrological process transforming rainfall into runoff at the basin-event scale. (Résumé d'auteur) specialized CLIMATOLOGIE SECHERESSE RESSOURCES EN EAU PLUVIOMETRIE BILAN HYDROLOGIQUE MODELISATION PLUIE DEBIT RELATION 1992 1995 NIGER 021CLIMAT01 062EVAEAU02 Servat Eric ed. edt IRD Hughes D. ed. edt IRD Fritsch Jean-Marie ed. edt IRD Hulme Mike ed. edt IRD 252 347-354 Wallingford AISH 1998 Water Resources Variability in Africa during the 20th Century : International Conference, Abidjan (CIV), 1998/11/16-19 252 https://www.documentation.ird.fr/hor/fdi:010017942 1-901502-65-1 [F A010017925] https://www.documentation.ird.fr/hor/fdi:010017942 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers09-04/010017942.pdf IRD - Base Horizon / Pleins textes 1999-04-20 2012-04-26 fdi:010017942 fre