Extreme indices of temperature and precipitation in South America: trends and intercomparison of regional climate models

Regional Climate Models (RCMs) provide climate information required for evaluating vulnerability, impacts, and adaptation at finer scales than their global driving models. As they explicitly resolve the basic conservation state equations, solve physics with more detail, conserving teleconnection of larger provided by Global (GCMs). In South America (SA), regional simulations have been historically evaluated principally on climatological aspects, but representativeness extremes still needs a profound assessment. This study aims to analyze three RCMs (RegCM4-7, REMO2015, Eta) driven different GCMs in SA, focusing capacity reproduce extreme historical indices daily precipitation temperature. The maximum consecutive 5 days (Rx5day), Consecutive Dry Days (CDD), minimum annual temperature (TXx TNn, respectively) were regarding spatio-temporal variability trends. Furthermore, projections 2071–2099 period, under Representative Concentration Pathway 8.5 scenario, analyzed. behavior (1981–2005) was compared two gridded products: Prediction Center (CPC) agrometeorological indicators derived from fifth generation reanalysis produced ECMWF (AgERA5), previously records meteorological stations evaluate them. results show that highest differences within products observed regions scarce surface (North West SA) complex topography (The Andes Cordillera), being pronounced precipitation-based indices. We found generally agreement spatial inter-annual all SA regions. When analyzing trends, models better reproduced long-term those rainfall. More disagreement Rx5day CDD including substantial heterogeneities both magnitude sign tendency. change exhibited significant warmer conditions TXx signals differed between GCM each model. Maximum dry spells are expected increase almost regions, whereas events consistent over southeastern (northern southwestern SA), positive (negative) changes end century.