ABSTRACT

The Mediterranean region is a climate change hotspot for water resources. However, uncertainty analyses of hydrological projections are rarely quantified. In this study, an in-depth analysis of projections and uncertainties for high and low flows is performed. Climatic projections derived from a recent downscaling method were used, for two representative concentration pathway scenarios (RCPs), five general circulation model/regional climate model (GCM/RCM) couples, three hydrological models (HMs), and 29 calibration schemes. A quasi-ergodic analysis of variance was used to evaluate the contribution of each impact modelling step to the total uncertainty. For high flows, the results show a mean increase of 30% by 2085, and RCPs make the highest contribution to the total uncertainty, followed by GCMs. For low flows, 50% of projections indicate a decrease of 7% or more by 2085, and HM structures, hydrological model parameters, and GCMs are the most important uncertainty sources. These results contribute to raise awareness among water managers regarding future hydrological extreme events.

摘要

地中海地区是水资源的气候变化热点。但是，很少对水文预测的不确定性分析进行量化。在这项研究中，对高流量和低流量的预测和不确定性进行了深入分析。对于两个代表性的浓度路径情景（RCP），五个常规循环模型/区域气候模型（GCM / RCM）对，三个水文模型（HMs）和29个校准方案，使用了从最近的降尺度方法得出的气候预测。使用准遍历方差分析来评估每个影响建模步骤对总不确定性的贡献。对于高流量，结果显示到2085年平均增加30％，RCP对总不确定性的贡献最大，其次是GCM。对于低流量，50％的预测表明到2085年将下降7％或更多，而HM结构，水文模型参数和GCM是最重要的不确定性来源。这些结果有助于提高水管理者对未来水文极端事件的认识。