Bader Jean-Claude auteur aut IRD Piedelievre J. P. auteur aut IRD Lamagat Jean-Pierre auteur aut IRD text journalArticle eng text/pdf reformatted digital access From the end of August to the beginning of October, the support of the annual flood of the Senegal River by the multipurpose Manantali Dam requires high release volumes, which can be problematic for its hydro-electric production. To facilitate the programming of this objective by predicting reserves available in the reservoir at the end of the monsoon, attempts are made to predict in August the natural flood volume of the river for September-October, starting from an index of pluviometric anomalies calculated at the end of July for these two months by the model "ARPEGE Climat". After a principal components analysis of these indexes produced on a 300 x 300 km grid covering West Africa, a 1200 x 1200 km zone may be determined shifted to the east of the basin, where the eigenvectors of the indexes are related to the natural discharge of September-October by linear regression with five parameters (R-2 = 0.651). This statistical relationship calculated for the period 19792000 is validated for the period 2001-2005. specialized West Africa principal components analysis Manantali Dam Senegal River reservoir operation ARPEGE model precipitation seasonal discharge forecast flood support SENEGAL 062 51 3 406-417 2006 0262-6667 https://www.documentation.ird.fr/hor/fdi:010053297 10.1623/hysj.51.3.406 0262-6667 [F B010053297] https://www.documentation.ird.fr/hor/fdi:010053297 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2025-01/010053297.pdf IRD - Base Horizon / Pleins textes 2006-08-10 2025-01-03 fdi:010053297 fre