This study investigates the extent of the affect of the El Nino/Southern Oscillation on South American streamflow. The response of South American precipitation and temperature to the extreme phases of ENSO (El Nino and La Nina events) is well documented (eg, Ropelewski and Halpert 1987, Rogers 1988, Kiladis and Diaz 1989, Tapley and Waylen 1990); but the response of Souther American hydrology has been barely studied (Waylen and Caviedes 1990, Mechoso and Iribarren 1992). Such paucity of research contrasts sharply with that available on the response of North American streamflow to ENSO events (eg, Kahya and Dracup 1993, Cayan and Webb 1993, Redmond and Koch 1991). This present study is based on a hydrologic study by Kahya and Dracup (1993) of North American streamflow and, with their techniques, examines South American streamflow. A schematic of our research approach is presented in Figure 1. In South America, regions with a coherent response to ENSO are identified, and by computing and analyzing the shift in the probability distribution for La Nina, non-ENSO, and El Nino events, we are able to represent and chart the South American streamflow anomalies.
El Niño–Southern Oscillation (ENSO); Hydrology; South America; Streamflow
Climate | Environmental Sciences | Fresh Water Studies
Piechota, T. C.,
Dracup, J. A.,
Brown, E. F.,
McMahon, T. A.,
Chiew, F. H.
South American Streamflow and the extreme phases of the southern oscillation.