Abstract

During the past few years, a progressive worldwide change of the climatic conditions has been observed that has consequently brought increases in the frequency and severity of phenomena like floods and droughts. Thus, it is necessary to have tools for making informed decisions. One way to assess the effects of the climate change on the hydrology of a river basin is to use a distributed hydrologic model, which once calibrated and validated is perturbed with changes (% of change in precipitation and Δ variation in temperature) obtained from different future climate scenarios. The objective of this work is to quantify by means of simulations done with a mathematical model perturbed with plausible scenarios of climatic change, the sensitivity of the hydrology of two sub-basins of the Biobío River. In addition, the amplitude in the response obtained from the hydrologic model perturbed with changes obtained from different Global Circulation Models is analyzed, and the impact to using signals of change derived from the application of more advanced regionalization methods is evaluated. The results indicate that for most of the modeled scenarios of climate change, a reduction in the mean monthly and annual flows will take place, being this variation greater in the spring and in the summer. These results allow to perform one of the first quantitative interpretations of the potential impacts of the climate change in the availability of water resources in the Biobío river basin.