The global water gap, water demand minus water supply, is expected to increase through 2100, negatively affecting agriculture, industry and households. Adaptation measures are necessary, but projections on their effectiveness and costs are currently unavailable. Here, we present an adaptation evaluation framework aimed at closing the water gap, which is applied offline at the global scale, and made available for regional decision making as a web service. It includes climate change and socioeconomic scenarios over the 21st century as drivers for global projections of water supply and demand. The transient water gap was calculated for 1604 water provinces globally and we determined the water gap reduction that could be achieved by three increasingly involved sets of adaptation measures. The median annual adaptation costs amount to 1.4–1.6% of the GDP per affected water province. The interactive web-based simulation allows users to include information that is not available at the global scale.

到2100年，全球缺水量（需水量减去供水量）预计将增加，对农业，工业和家庭产生负面影响。适应措施是必要的，但目前尚无关于其有效性和成本的预测。在这里，我们提出了一个旨在缩小水缺的适应性评估框架，该框架已在全球范围内离线应用，可作为网络服务用于区域决策。它包括21世纪的气候变化和社会经济情景，作为对全球水供需预测的驱动力。计算了全球1604个水省的瞬时水位差，我们确定了可通过三套越来越多地涉及的适应措施来实现的水位差减少。年度适应费用中位数为1.4-1。每个受影响的水省的GDP的6％。基于交互式Web的模拟使用户可以包含全球范围内不可用的信息。