The 2010-2012 Anomalous Wet Season in Northern South America

Tuesday, 16 December 2014
John Alejandro Martinez-Agudelo1, Paola Andrea Arias2 and Sara Cristina Vieira2, (1)University of Arizona, Tucson, AZ, United States, (2)Universidad de Antioquia, Escuela Ambiental, Grupo de Ingeniería y Gestión Ambiental (GIGA), Medellín, Colombia
During 2010-2012, northern South America experienced one of the strongest wet seasons during the recent decades, with socio-economic implications of wide proportions. This period was characterized by two stronger-than-average La Niña events, occurred in 2010-2011 and 2011-2012. This study focuses on identifying the main moisture sources for the anomalous wet season occurred in this region during this period and their association with the La Niña events observed in the equatorial Pacific. Our results suggest that the main moisture sources to this anomalous wet season were the Pacific Ocean (via the westerly flow of the Choco jet) and the Caribbean Sea (via the weakening of the Caribbean low-level jet). These changes appear to be associated not only to El Niño-Southern Oscillation (ENSO)-driven sea surface temperature anomalies in the eastern Pacific, Caribbean Sea, and north Atlantic, but also to ENSO-independent variability in the Atlantic Ocean.