Global glacier retreat driven by climate change will have major impacts on regional water availability, as many communities rely on glacier runoff for water supply during warm and dry seasons. A community whose water resources are potentially vulnerable is one that sources water from a glacier-fed river where that river is expected to substantially change if glacier contributions become negligible. However, regional assessments identifying which communities’ water resources are most vulnerable to such changes are lacking. Here we use observed streamflow measurements, gridded climate data and a database of municipal water sources for communities in Alberta, Canada, to identify the relative importance of glacier runoff at the local scale. In a scenario of negligible glacier runoff, we predict unprecedented streamflow lows at several communities. This approach provides a methodology to identify communities whose water resources may be vulnerable to glacier retreat and would benefit from more-focused research.

由于许多社区在温暖和干旱季节都依赖冰川径流来供水，因此气候变化驱动的全球冰川退缩将对区域水资源供应产生重大影响。一个水资源潜在脆弱的社区是从冰川河中取水的，如果冰川的贡献可忽略不计，则该河流将发生实质性变化。但是，缺乏确定哪些社区的水资源最容易受到这种变化影响的区域评估。在这里，我们使用观测到的流量测量结果，网格化的气候数据以及加拿大艾伯塔省社区的市政水源数据库，来确定冰川径流在当地范围内的相对重要性。在冰川径流可忽略不计的情况下，我们预测了几个社区的空前流量低点。