Vulnerability of water resources in the face of potential climate change: generation of hydroelectric power in Colombia

Abstract

This work identifies some of the climate-hydrological variables that best express the vulnerability of hydrological resources at watershed level (Sinu-Caribbean Basin, Colombia). The analysis utilizes the outputs of some general circulation models runs under different scenarios of greenhouse gas emissions (A2 and B2). The IPCC has produced diverse scenarios of greenhouse gas emissions, reported in the Special Report on Emissions Scenarios (SPES) (IPCC, 2001). Statistical downscaling models (SDSM) are used that allow the observation of climate change at local level; the Water Evaluation and Planning System (WEAP), an integrated approach to simulate water systems and orient management policies, is applied as well as certain mathematical analyses and statistical methods. Thus, the study visualizes and analyzes the incidence of potential climate change on the hydroelectric sector, finding the degree of vulnerability for this or any other sector that relies on water as a source, and offers tools, strategies and criteria for the planning and orientation of projections in the different productive sectors. The results predict increases in maximum, mean and minimum temperatures, for example, the maximum temperature before the end of the century could rise from 1.3 degrees to 2.5 degrees C in scenario A2 and from 0.9 degrees to 1.7 degrees C in B2; an increase in precipitation is estimated up to approximately 30.4\% in A2 and 27.9\% in B2. The number of extreme events forecast is found over previously determined thresholds; an estimation is made of the water balance and the relation of the above variables to the Sinu River inflow to the Urra 1 dam and the generation of hydroelectric energy. Changes in the generation of hydroelectric energy vary from 0.6 to -35.2\% for the period 2010 to 2039, reduction in the Sinu River inflow to the dam in a range of -2.3 to -34.9\% and a drop in the stored volume in the dam of -0.9 to -29.4 percent in relation to the maximum storage capacity (MSC), according to the analyzed scenario.