INVESTIGADORES
VERA Carolina Susana
artículos
Título:
Precipitation interannual variability in South America from the WCRP-CMIP3 multi-model dataset
Autor/es:
VERA, CAROLINA; SILVESTRI, GABRIEL
Revista:
CLIMATE DYNAMICS
Editorial:
Springer-Verlag
Referencias:
Lugar: Berlin, Alemania; Año: 2009 vol. 32 p. 1003 - 1014
ISSN:
0930-7575
Resumen:
The ability of coupled climate models from theWCRP-CMIP3 multi-model dataset to reproduce theinterannual seasonal variability of precipitation in SouthAmerica and the influence of the Southern Annular Mode(SAM) and El Nin˜o-Southern Oscillation (ENSO) on suchvariability is examined. Models are able to reproduce thenorthward migration of the precipitation variability maximumduring autumn and winter and its later return towardsthe south during spring and summer as well as the highvariability throughout the year in southern Chile. Nevertheless,most of them have problems in representingaccurately the variability associated with the South Atlanticconvergence zone during summer and the typical maximumof variability in the subtropical continent duringautumn and winter. The annular-like structure characteristicof the SAM influence on the Southern Hemispherecirculation is basically simulated by all models, but theyhave serious deficiencies in representing the observedrelationship between SAM and both precipitation and circulationanomalies in South America. In addition, most ofthe models are not able to reproduce the typical wavetrainsobserved in the circulation anomalies in the SouthernHemisphere associated to ENSO. Only few models, previouslyidentified as those with reasonable ENSOrepresentation at the equatorial Pacific, have evidences ofsuch wavetrains. Coherently, they exhibit the best representationof the ENSO signal in the South American precipitation. Results show that considerable improvementin the model representation of the climate variability inSouth America and in the associated large-scale teleconnectionsis still needed.