The extreme 2014 flood in south-western Amazon basin : the role of tropical-subtropical South Atlantic SST gradient Espinoza, J. C. Marengo, J. A. Ronchail, J. Carpio, J. M. Flores, L. N. /Guyot, Jean-Loup extreme flood Amazon basin Madeira river Bolivian Amazon Brazilian Amazon Unprecedented wet conditions are reported in the 2014 summer (December-March) in Southwestern Amazon, with rainfall about 100% above normal. Discharge in the Madeira River (the main southern Amazon tributary) has been 74% higher than normal (58 000 m(3) s(-1)) at Porto Velho and 380% (25 000 m(3) s(-1)) at Rurrenabaque, at the exit of the Andes in summer, while levels of the Rio Negro at Manaus were 29.47 m in June 2014, corresponding to the fifth highest record during the 113 years record of the Rio Negro. While previous floods in Amazonia have been related to La Nina and/or warmer than normal tropical South Atlantic, the 2014 rainfall and flood anomalies are associated with warm condition in the western Pacific-Indian Ocean and with an exceptionally warm Subtropical South Atlantic. Our results suggest that the tropical and subtropical South Atlantic SST gradient is a main driver for moisture transport from the Atlantic toward south-western Amazon, and this became exceptionally intense during summer of 2014. 2014 text https://www.documentation.ird.fr/hor/fdi:010063643 fdi:010063643 Espinoza J. C., Marengo J. A., Ronchail J., Carpio J. M., Flores L. N., Guyot Jean-Loup. The extreme 2014 flood in south-western Amazon basin : the role of tropical-subtropical South Atlantic SST gradient. 2014, 9 (12), art. 124007 [9 ] EN AMAZONE BASSIN BOLIVIE BRESIL ATLANTIQUE ZONE TROPICALE