INVESTIGADORES
PENALBA Olga Clorinda
congresos y reuniones científicas
Título:
Precipitation response to El Niño/La Niña events in Southern South America. emphasis in regional drought events
Autor/es:
PENALBA OC, RIVERA JA
Reunión:
Conferencia; III International Conference on ENSO: Bridging the gaps between Global ENSO Science and regional processes, extremes and impacts; 2014
Resumen:
The ENSO phenomenon is one of the key factors that influence the interannual
variability of precipitation over Southern South America (SSA). The aim of this
study is to identify the regional response of precipitation to El Niño/La Niña
events, with emphasis in drought conditions. The standardized precipitation
index (SPI) was used to characterize precipitation variabilities through the 1961-
2008 period. In order to identify the regional influence of El Niño and La Niña
events on the SPI time series, we calculated the mean SPI values for the El
Niño and La Niña years and assessed its significance through bootstrap
analysis. We found coherent and significant SPI responses to ENSO phases in
most of the seven regions considered, mainly for the 12 months SPI time series.
The precipitation response to La Niña events is characterized with regional
deficits, identified with negative values of the SPI during the end of La Niña year
and the year after. During El Niño events the precipitation response is reversed
and more intense than in the case of La Niña events.