Multi-coupling analysis of temperate glacier stability: A case study of Midui glacier on Tibet, China

Abstract. Temperate glaciers are particularly sensitive to climate warming. The instability of temperate glaciers and their geohazards chains threaten the safety of residents and engineering facilities. However, limited attention has been paid to the quantitative assessment of the stability of temperate glaciers, and the response of dynamic characteristics and hydrothermal distribution to climate change is still unclear. Herein, based on thermo-hydromechanical numerical simulation, the dynamic characteristics and hydrothermal variation of temperate glaciers are analyzed, and a conceptual model for quantitative evaluation of the stability and potential collapse area is proposed. The results show that: (1) The low temperature area is mainly concentrated in the glacier upper reaches. The minimum temperature of the glacier in the cold and warm season can reach −10 and −8 ℃, respectively, and the basal temperature is maintained at melting point temperature. (2) The maximum flow velocity in the cold and warm seasons are 45 and 50 m/yr, respectively. The maximum flow velocity is concentrated in the area with the largest glacier thickness. (3) The glacier instability strip is located in the glacier upper reaches. During the year, the factor of safety reached a maximum of 2.03 in February and a minimum of 1.48 in August.