CLIMATE CHANGE IN COLOMBIA: TRENDS TURING THE SECOND HALF OF THE 20TH CENTURY AND POSSIBLE SCENARIOS FOR 21ST CENTURY

Abstract

Using the statistical tool RClimex applied to the climatological time series of different regions of Colombian territory, a reassessment of the long term trends observed in air temperature, precipitation and extreme events during the second half of the 20th Century was made; additionally, supported by climate modeling and using the A2 and B2 IPCC climate change scenarios, regional scenarios were elaborated to provide the possible conditions will be observed over Colombia during the 21 st Century. The identified trends corroborate the widespread warming of 0,1-0,2°C/decade, a decreasing of annual number of frost days and an increasing of the maximum temperatures frequency; the results also indicate the changes (reduction and increasing) have been occurring over different regions of Colombian territory in both annual precipitation and rainfall extreme events frequency. The elaborated scenarios show a gradual increase of air temperature in the range of 2-3°C for 2011-2040 and 3-4°C for 2071-2100 periods, however over Magdalena and Cauca valleys the warming could be greater than the rest of the regions; at the end of 21 st Century the annual precipitation could be reduced in 30% over the interandean area, and in the Caribbean region, meanwhile in the Pacific region, the eastern foothills of Eastern Cordillera, and in a zone of Bolivar and Sucre the precipitation could be increase in 30% of the annual amounts observed during 1961-1990.