Department of Geotechnical Engineering and Geoscience, Technical University of Catalonia-UPC, 08034, Barcelona, Spain.
Sci Total Environ. 2012 Dec 1;440:253-60. doi: 10.1016/j.scitotenv.2012.06.062. Epub 2012 Jul 12.
Gaining knowledge on potential climate change impacts on water resources is a complex process which depends on numerical models capable of describing these processes in quantitative terms. Under limited data or ungauged basin conditions, which constrain the modelling approach, a physically based coherent methodological approach is required. The traditional approach to assess flow regime and groundwater recharge impacts, based on coupling general atmosphere-ocean circulation models (GCM) and hydrologic models, has been investigated in the Siurana ungauged catchment (NE Spain). The future A2 (medium-high) and B1 (medium-low) greenhouse gas scenarios and time slices 2013-2037 (2025) and 2038-2062 (2050), developed by the Intergovernmental Panel on Climate Change (IPCC, 2001), have been selected. For scenario simulations, coupled GCM ECHAM5 scenarios, stochastically downscaled outputs and surface-subsurface modelling to simulate changes in water resources were applied to the catchment. Flow regime analysis was assessed by HEC-HMS, a physically based hydrologic model to assess rainfall-runoff in a catchment, while recharge was estimated with VisualBALAN, a distributed model for natural recharge estimation. Simulations show that the projected climate change at the catchment will affect the entire hydrological system with a maximum of 56% reduction of water resources. While subtle changes are observed for the 2025 time slice, the temperature and precipitation forecast for 2050 shows a maximum increase of 2.2 °C and a decreased precipitation volume of 11.3% in relation to historical values. Regarding historical values, runoff output shows a maximum 20% decrease, and 18% decrease of natural recharge with a certain delay in relation to runoff and rainfall data. According to the results, the most important parameters conditioning future water resources are changes in climatic parameters, but they are highly dependent on soil moisture conditions.
获取有关水资源潜在气候变化影响的知识是一个复杂的过程，这取决于能够以定量方式描述这些过程的数值模型。在数据有限或未测流域条件下，需要采用基于物理的连贯方法。在 Siurana 未测流域（西班牙东北部）中，已经研究了基于耦合通用大气-海洋环流模型（GCM）和水文模型来评估水流状况和地下水补给影响的传统方法。选择了由政府间气候变化专门委员会（IPCC，2001 年）开发的未来 A2（中高）和 B1（中低）温室气体情景以及时间片 2013-2037（2025 年）和 2038-2062（2050 年）。对于情景模拟，应用耦合 GCM ECHAM5 情景、随机降尺度输出和地表水-地下水模型来模拟水资源变化。使用基于物理的水文模型 HEC-HMS 评估水流状况分析，使用分布式模型 VisualBALAN 估计补给量。模拟结果表明，集水区的预计气候变化将影响整个水文系统，水资源减少最多可达 56%。虽然 2025 年时间片观察到细微变化，但 2050 年的温度和降水预测显示，与历史值相比，最高温度增加 2.2°C，降水量减少 11.3%。关于历史值，径流出量显示最大减少 20%，自然补给减少 18%，与径流量和降水数据相比有一定的延迟。根据结果，影响未来水资源的最重要参数是气候参数的变化，但它们高度依赖于土壤湿度条件。
