CMIP5 climate change hydroclimatic projections for Central America

Abstract

A review of a series of articles related to the use of General Circulation Models (GCMs) projections for characterizing future climate changes in Central America are presented. Previous work using Coupled Model Intercomparison Project 5 (CMIP3) models showed that aridity and drought (reflected for example in reductions in runoff, streamflow, and precipitation) will be more frequent in the future under low and high emission scenarios (B1 and A2). Data from 107 GCM runs from the CMIP5 version, were evaluated and ranked according to their skill in reproducing observed climatological temperature and precipitation patterns, as well as realistic El Niño-Southern Oscillation (ENSO) precipitation teleconnection patterns. The best 14 model runs were used in a projection of precipitation and temperature changes for the mid-century horizon. It is shown that for two forcing scenarios RCP4.5 and RCP8.5 the northern (southern) part of Central America will be drier (wetter) in the future than the baseline (historical) scenario. This is important, as the north-south socioeconomic contrast suggests that northern countries will suffer the most as a result of climate change, due to increased social vulnerabilities and aridity. The Caribbean Low-Level Jet (an important feature of the regional climate) show little change at mid-century horizons. The most significant changes for the mid-summer drought (MSD) in the future are for the duration, which is projected to increase by an average of over a week, and the MSD minimum precipitation, which is projected to decrease.