Horizontal Approach to Assess the Impact of Climate Change on Water Resources Systems

Abstract

The typical approach to assess climate change impacts on water resources systems is based on a vertical integration/coupling of models. Since the range of uncertainty that can be explored with GCM is limited, researchers rely on ensembles to enlarge the spread, making the modeling approach even more demanding in terms of computation time and resource. When a particular water system must be analyzed, the question is to know whether this computationally intensive vertical approach is necessary in the first place or if we could rely on projections available in neighboring systems? The proposed study addresses this question by comparing the performance of a water resource system under future climate conditions using the vertical and the horizontal approaches. The methodology is illustrated with the hydropower system of the Gatineau River Basin in Quebec, Canada. The analysis of the simulation results reveals that the annual and weekly energy productions of the system derived from both the vertical and the horizontal approaches are similar.