Hydrological characterization and connectivity of proglacial lakes to a stream, Adygine ice-debris complex, northern Tien Shan
Abstrakt
In this study, we characterized the glacial meltwater flow through a proglacial area with a focus on proglacial lakes, their hydrological regime and their connection to the stream. The studied lakes - the Adygine ice-debris complex, northern Tien Shan - showed a distinct development throughout an ablation season: at Lake 2, the mean daily water-level fluctuation amplitude increased from 0.07 m to 0.18 m (June, August), then dropped to 0.07 m in September.
Glacial meltwater flows through the lakes and further downstream through a rock glacier rather fast, moving at 0.085 m s-1. However, based on the low dye recovery in the stream (0.03%), only a small portion of water was routed efficiently.
The complexity of the site's drainage system was supported by varying isotopic composition of water in the tarns situated on the rock glacier, with Tarn a (δ2H: -36.08%o; δ18O: -6.25%o) being the most enriched and Tarn c (δ2H: 78.68%o; δ18O: 11.9%o) the most depleted in heavy isotopes.