Water availability is of paramount importance for sustainable development and environmental planning, specifically in regions such as the Iberian Peninsula, renowned for diverse landscapes and varying climatic conditions. Due to climate change, understanding the potential impacts on water resources becomes essential for effective water management strategies. This research effort aims to assess future potential water availability for the Iberian Peninsula in different climate scenarios, employing cutting-edge water resource modelling techniques integrated within a geographic information system (GIS) framework. In this study, potential water availability is defined as the annual demand for water that can be satisfied at a specific point in the fluvial network with certain reliability. An ensemble of state-of-the-art climate models is utilised to project runoff for the Iberian Peninsula during the mid- and late-twenty-first century periods. These climate projections were subsequently processed using the GIS-based water resource management model, WAAPA, to derive potential water availability under a range of realistic hypotheses. The results indicate that anticipated shifts in precipitation patterns will lead to alterations in hydrological regimes across the region, significantly impacting future water availability. By using GIS-based methodologies, we can facilitate the identification of vulnerable areas susceptible to changes in water availability, offering spatially explicit information along the main rivers of the Iberian Peninsula for decision-makers and stakeholders. High-resolution spatial outputs from this research and detailed water availability estimates serve as valuable input for integrated water resource management and climate change adaptation planning. By combining advanced GIS-based hydrological modelling with climate scenarios, this research presents a robust framework for assessing water resources amidst a changing climate, applicable to other regions struggling with analogous challenges. Ultimately, our study provides vital insights for policymakers and stakeholders, empowering them to make informed decisions and devise adaptive measures to ensure sustainable use of water resources despite uncertain future climatic conditions.

水资源供应对于可持续发展和环境规划至关重要，特别是在伊比利亚半岛等以多样化景观和多变气候条件而闻名的地区。由于气候变化，了解对水资源的潜在影响对于有效的水资源管理战略至关重要。这项研究工作旨在采用集成在地理信息系统（GIS）框架内的尖端水资源建模技术，评估伊比利亚半岛在不同气候情景下未来潜在的可用水量。在本研究中，潜在可用水量定义为河流网络中特定点在一定可靠性下能够满足的年用水需求。利用最先进的气候模型集合来预测二十一世纪中后期伊比利亚半岛的径流。这些气候预测随后使用基于 GIS 的水资源管理模型 WAAPA 进行处理，以在一系列现实假设下得出潜在的可用水量。结果表明，降水模式的预期变化将导致整个地区水文状况的变化，从而显着影响未来的水资源供应。通过使用基于 GIS 的方法，我们可以帮助识别易受水资源供应变化影响的脆弱地区，为决策者和利益相关者提供伊比利亚半岛主要河流沿线的明确空间信息。这项研究的高分辨率空间输出和详细的可用水量估计为综合水资源管理和气候变化适应规划提供了宝贵的输入。 通过将先进的基于 GIS 的水文模型与气候情景相结合，这项研究提出了一个强大的框架，用于在气候变化的情况下评估水资源，适用于其他面临类似挑战的地区。最终，我们的研究为政策制定者和利益相关者提供了重要的见解，使他们能够做出明智的决策并制定适应性措施，以确保在未来气候条件不确定的情况下可持续利用水资源。