Inundations in the Mamoré basin (south-western Amazon-Bolivia) and sea-surface temperature in the Pacific and Atlantic Oceans

Rainfall in the Mamoré basin is hardly associated with Sea Surface Temperature Anomalies (SSTA) in the Pacific and Atlantic Oceans during the 1952-1953/1998-1999 period. However, during the nineties the southern Atlantic SSTA account for 50 percent of rainfall variability. Inundations are also related to negative SSTA differences between the tropical and subtropical southern Atlantic. Two thirds of the 22 inundation events occurred in association with this oceanic anomaly that features a weak SSTA gradient in the southern Atlantic. During the 1988-1989/1998-1999 period, a particularly significant relation can be observed between SSTA and inundations events. Despite being associated with major El Niño events (1982-1983, 1991-1992), inundations are not significantly related to the equatorial Pacific SSTA.