Abstract
Meltwater from mountain glacier and ice cap plays an important role for freshwater resources in lowlands of river basins. However their impacts on water availability have not yet been explicitly taken into account in published global water resources assessments. Therefore, we investigated the contribution of glacier meltwater to total water availability on a global-scale by combining a global hydrological model and a global glacier model. The maximum monthly percentage of glacier meltwater to river flow was above 90% in the Tarim and the Aral basins. In the neighboring countries of these basins, the contribution of glacier meltwater withdrawal to total water withdrawal was high in summer, especially on Kyrgyzstan (51.6%) and Afghanistan (26.2%). Annual glacier meltwater withdrawal from river flow in Kyrgyzstan and Afghanistan was approximately 0.460 and 0.226 km3, respectively. It was approximately 2.02% and 8.86% of the storage capacity of large-reservoirs in Kyrgyzstan and Afghanistan, respectively. We provided a new framework of water availability assessment including the effect of glacier meltwater.
