Onset and end of the rainy season in South America in observations and the ECHAM 4.5 atmospheric general circulation model - Liebman, Brant; Camargo, Suzana J; Seth, Anji; Marengo, Jose A; Carvalho, Leila Maria Véspoli; Allured, Dave; Fu, Rong; Vera, Carolina S (Journal of Climate, 2007)