An approach to extracting surface supply relationships between glaciers and lakes on the Tibetan Plateau

Surface supply relationships between glaciers and lakes are needed to analyze and understand hydrological processes at regional and global scales. However, these supply relationships still cannot be extracted efficiently by existing methods. This paper proposes an automatic and efficient approach to extracting surface supply relationships between glaciers and lakes based on meltwater flow paths. The approach includes two stages: (1) identifying direct connections between objects (i.e. glaciers and lakes) based on flow direction derived from digital terrain analysis on a gridded digital elevation model (DEM) and (2) deriving all (or user-specified) kinds of surface supply relationships based on graph search. All computation-intensive steps in this approach have been parallelized; and all steps in the proposed approach have been integrated as an automatic program. Results for the Tibetan Plateau show that given outline data for glaciers and lakes and the Shuttle Radar Topography Mission DEM, the proposed approach can automatically derive diverse surface supply relationships under user-specified restrictions on the attributes of the supply route. The parallelization in the approach effectively improves the computing efficiency. The proposed approach could also be applied to developing a detailed fundamental dataset of supply relationships between glaciers and lakes for other region or period.