Publications des scientifiques de l'IRD

Villar J. C. E., Guyot Jean-Loup, Ronchail Josyane, Cochonneau Gérard, Filizola N., Fraizy Pascal, Labat D., de Oliveira E., Ordonez J. J., Vauchel Philippe. (2009). Contrasting regional discharge evolutions in the Amazon basin (1974-2004). Journal of Hydrology, 375 (3-4), p. 297-311. ISSN 0022-1694.

Titre du document
Contrasting regional discharge evolutions in the Amazon basin (1974-2004)
Année de publication
2009
Type de document
Article référencé dans le Web of Science WOS:000270472100001
Auteurs
Villar J. C. E., Guyot Jean-Loup, Ronchail Josyane, Cochonneau Gérard, Filizola N., Fraizy Pascal, Labat D., de Oliveira E., Ordonez J. J., Vauchel Philippe
Source
Journal of Hydrology, 2009, 375 (3-4), p. 297-311 ISSN 0022-1694
Former hydrological studies in the Amazon Basin generally describe annual discharge variability on the main stem. However, the downstream Amazon River only represents the mean state of the Amazonian hydrological system. This study therefore uses a new data set including daily discharge in 18 sub-basins to analyze the variability of regional extremes in the Amazon basin, after recalling the diversity of the hydrological annual cycles within the Amazon basin. Several statistical tests are applied in order to detect trends and breaks in the time series. We show that during the 1974-2004 period, the stability of the mean discharge on the main stem in Obidos is explained by opposite regional features that principally involve Andean rivers: a decrease in the low stage runoff, particularly important in the southern regions, and an increase in the high stage runoff in the northwestern region. Both features are observed from the beginning of the nineties. These features are also observed in smaller meridian sub-basins in Peru and Bolivia. Moreover we show that the changes in discharge extremes are related to the regional pluriannual rainfall variability and the associated atmospheric circulation as well as to tropical large-scale climatic indicators.
Plan de classement
Hydrologie [062]
Localisation
Fonds IRD [F B010048252]
Identifiant IRD
fdi:010048252
Contact