CR 68:137-149 (2016)  -  DOI: https://doi.org/10.3354/cr01340

ABSTRACT: The Köppen-Trewartha climate classification was applied to regional climate model (RCM) simulations obtained in the frame of the CLARIS-LPB EU project to assess the ability of RCMs to reproduce the climate in South America and to inquire into the extent, magnitude and trend of the expected climate change in this region. Three sets of simulations were analysed: hindcast simulations, in which RCMs were driven by ERA-Interim reanalysis; historical simulations, where RCMs were nested in general circulation models (GCMs) for the period 1961-1990; and scenario simulations, where RCMs were driven by the SRES A1B scenario simulations performed by GCMs for 2 periods, 2011-2040 and 2071-2100. The co-occurrence matrices used allow a grid-to-grid comparison of climates derived from both hindcast simulations and observations. They also allow the comparison of simulations for 2 different periods. The climates of almost 70% of the surface of the domain were correctly described by the ensemble of the regional model hindcast simulations, with the main difference with observations being the location of the line between the 2 tropical climates. The historical simulations reached an agreement of 60.9% with the observations. It is projected that 12% of the area of South America will be affected by significant climate changes for 2011-2040 and around 27% for 2071-2100. Transitions to wetter climates are mainly found in the northern half of Argentina. Transitions to drier climates are principally projected over Brazil. Very strong climate changes are expected in some zones of the Andes mountain range. The climate that appears to be involved in a greater number of future transitions is the subtropical humid climate.

KEY WORDS: Climate change · Regional climate · South America · Köppen-Trewartha classification