Accurate characterization of peak snow water storage in High Mountain
Asia (HMA) is essential for assessing the water supply to over one
billion downstream residents. Currently, such characterization still
relies on modeling due to the measurement scarcity. Here, eight global
snow products were examined over HMA using a newly developed High
Mountain Asia Snow Reanalysis (HMASR) dataset as a reference. The focus
of intercomparison was on peak annual snow storage, the first-order
determinant of warm-season water availability in snow-dominated basins.
Across eight products the climatological peak storage over HMA was found
to be 161 km3 ± 102 km3 with an
average 33% underestimation relative to HMASR. The inter-product
variability in cumulative snowfall (335 km3 ± 148
km3) explains the majority (>80%) of
peak snow storage uncertainty, while significant snowfall loss to
ablation during accumulation season (51% ± 9%) also reveals the
critical role of ablation processes on peak snow storage.