View article

Mountainous areas play a crucial role in global water resources. Orographic precipitation provides mountains with disproportionately high precipitation, which can be stored seasonally or over many years as snow and ice. Therefore, mountains are often referred to as ‘water towers’, emphasising their vital contribution to water provision for human use. Nevertheless, on a global scale, knowledge about their relevance for lowlands is limited, especially beyond long-term annual averages (Viviroli et al., 2020). Therefore, this study aimed to first assess differences in the water supply of mountains and lowlands in large river basins globally. Second, the share of mountain runoff in lowland water abstractions was evaluated with a focus on monthly averages and intra-and interannual variability to identify hotspots of mountain importance.

Our study is based on global simulations of the large-scale hydrological model CWatM …