Modeling runoff from the inylchek glaciers and filling of ice‐dammed lake merzbacher, central tian shan

Abstract

We developed a spatially distributed conceptual melt and runoff model able to cope with debris covered glacier parts. Subdebris melt was calculated based on empirical equations derived from field observations. The model was applied at the nylchek glaciers. While runoff from outhern nylchek flows directly into nylchek iver, runoff from orthern nylchek is blocked by outhern nylchek and forms ake erzbacher. This lake is drained frequently by outburst floods. To calibrate the model, a multi‐algorithm, genetically adaptive multi‐objective method () was used. Daily runoff observations from nylchek iver as well as glacier mass balance gradients from other glaciers in the ian han were used as objective functions in three split samples. Runoff simulations yielded ash–utcliffe coefficients mostly higher than 0.9, and the mass balance gradients were simulated in an acceptable range. The results of the different split samples vary considerably. Considering the used objective functions and additional data such as the equilibrium line altitude, we chose the most promising parameter set to calculate the filling of ake erzbacher. This analysis indicated answers to several questions concerning the hydrological system of the lake. Apart from calving at the ice dam formed by outhern nylchek glacier, the lake seemed so be filled predominantly by meltwater from orthern nylchek glacier. The lake has a permanent runoff, also during the filling process. After the outburst, the channels seemed to be closed quickly.