Synoptic sea level pressure patterns–daily rainfall relationship over the Argentine Pampas in a multi-model simulation

Abstract

The ability of 17 global circulation models to simulate daily rainfall of the Pampas region is assessed for winter and summer, key seasons for crop production in the region. Principal Component Analysis combined with k-means Cluster Analysis is employed to examine the models' representation of the relationship between daily sea level pressure of southern South America and rainfall. Models represent this relationship better for winter, reflecting their ability to reproduce winter synoptic scale patterns associated with rainfall. They precipitate too frequently at low intensity and less frequently at high intensity. This characteristic is more accentuated in winter.