CMIP3 projected changes in the annual cycle of the South American monsoon

Abstract

A warmer world will spur many changes in weather patterns and ecosystems. It is critical to predict these changes in order to mitigate their potential negative impacts. The South American monsoon is vulnerable to these changes and their prediction will assist farmers in this region in adapting. In this study, nine CMIP3 models (CCSM3, PCM, ECHAM5/MPI-OM, HadCM3, GFDL CM2, IPSL CM4, HadGEM1, MIROC3.2, CSIRO Mk3) are used to predict changes in onset, precipitation, and location of heaviest rainfall in the South American Monsoon System (SAMS). Despite the variance in model results, statistically significant changes in continental precipitation were revealed. They include reduced spring precipitation, movement in maximum precipitation, and displacement of the South Atlantic Anticyclone (SAAC). Further analysis is suggested to fully reveal and understand the impact of climate change on the South American Monsoon.