科奇喀尔冰川夏季表碛区热量平衡参数的估算分析

利用能量平衡原理、热传导理论和通量传输理论建立了一个热量平衡参数的估算模型, 对西天山的科奇喀尔冰川夏季消融区中部表碛区的热量平衡参数进行估算与分析. 结果表明: 净辐射是表碛面热量收支的主要热源, 吸收的热量主要以潜热和感热的形式向大气输送水汽和热量, 剩余部分用于表碛增温耗热. 与消融区上部的冰面和表碛面相比, 在消融区中部表碛面热量收入中感热输送减小, 同时向上的地热输送增加. 热平衡支出项中, 感热交换、蒸发耗热和地热通量的比例分别为39.1%、 39.9%和21%, 其中感热通量与蒸发耗热的比例比消融区上部有所提高, 蒸发耗热的增加比较显著. 在总的热量支出中, 平均只有7.8%的热量可以用于表碛下部的增温和向深层传导.

Estimation and Analysis of Heat Balance Parameters in the Ablation Season of Debris-Covered Kerqikaer Glacier, Tianshan Mountains

A simple model is developed to estimate the heat balance parameters in the ablation season of the debris-covered Kerqikaer Glacier on the basis of energy balance theory, heat conductivity and heat flux transfer. The model outputs include sensible heat flux, latent heat flux, ground heat flux and net radiation. Analyses on the outputs show that net radiation is the primary heat source, and the heat absorbed in the debris cover is lost mainly in the form of sensible heat and latent heat for moisture and heat exchanges between debris cover and air, and only about 21^0% is stored in the debris cover. One of the features of heat income over the debris-covered middle ablation area is that the ratio of the sensible heat flux decreases while ground heat flux increases significantly in comparison with that on the ice surface and debris cover in the upper ablation area. The heat outcome comprises sensible heat exchange, heat for evaporation and downward ground heat flux with the ratio of 39^1%, 39^9% and 21%, respectively. Heat for evaporation is significant in the heat outcome in comparison with that on the upper ablation area. Of the total heat income, only 7.8% is used for temperature increase of the deeper part of the debris cover and conduction downwards.