About the relations between ENSO and rainfalls in the Southeast of South America

The present work provides a realistic description of the spatial distribution patterns of the teleconection intensity between the ENSO and the precipitation on the basin of the Uruguay river region, at the Southeastern of South America.

Previous analysis carried out based on scarce punctual data are expounded again, now using data series in grid points. In this way, a homogeneously distributed virtual net with equal sized records is used, on the basis of all the stations of the region under study (more than 250).

An analysis of the precipitation patterns and the possible influences of the ENSO phenomenon over a transition region between the subtropical regimes and the mean latitudes was carried out.

Many relationships among the warm, cold and neutral phases of the ENSO and the maxima of precipitation were found.

The conclusions of this work enhance the knowledge of the climatic characteristics of the Uruguay River Basin and also the possibilities of a confident climatic prediction.

The most important results are linked to the spatial coincidence between the maxima of precipitation in the region, which are at the same time the maxima on the Rio de La Plata Basin, and the zones of the great intensity of the ENSO signal on the region; particularly in the months from September to December during the phase El Niño on the Pacific Ocean.