基于能量平衡对额尔齐斯河流域融雪过程的研究

为定量描述额尔齐斯河流域积雪的消融过程,建立了利用基于能量平衡的积雪模型,对流域内库威积雪站2014年1月4日-3月28日积雪的积累和消融过程进行了模拟.结果表明:模型能够很好的模拟出融雪期净辐射能量的变化过程,对雪水当量的模拟结果也非常好,雪水当量的观测值和模拟值之间的Nash系数达到了0.989.在积雪的积累期,雪表的净辐射、感热、潜热通量的绝对值以及地表热通量明显低于积雪的消融期.在积累期,感热和潜热通量以及土壤热通量受到雪层厚度的影响.当雪水当量小于10 mm时,感热和潜热通量的绝对值偏高,土壤热通量的波动性也偏大.在积累期积雪的物质损失全部为升华损失,升华量为2.74 mm;在消融期,积雪的融化量为66.26 mm,升华量为2.04 mm.净辐射对积雪物质损失的贡献达到了83.1%,湍流通量对积雪物质损失的贡献达到16.9%.由于在融化期土壤热通量为正值,因此土壤热通量对融雪没有贡献.

Analysis of water and heat transfer in snow layer during snowmelt period in Irtysh River Basin based on energy balance theory

In order to quantitatively describe the melting process of snow cover in Irtysh River Basin,a single layer energy and water balance model was constructed for modeling the snow accumulation and ablation process-es during January 4 and March 28,2014 in Kuwei station of the basin. The results showed that the model can well simulate the changing process of the net radiation,and the simulation results of snow water equivalent was also very good,the Nash coefficient between the observed snow water equivalent and simulated values had reached 0. 989. The net radiation,sensible heat,absolute value of latent heat flux and the surface heat flux in the snow accumulation period were significantly lower than accumulation period. In the accumulation period,the sensible heat and latent heat flux and soil heat flux is affected by the thickness of the snow,when the snow water equivalent was less than 10 mm,sensible and the absolute value latent heat fluxes is higher,and the volatility of the soil heat flux was larger. In the accumulation period,the material loss of snow cover was all sublimation loss,and the sublimation amount was 2. 74 mm. During the ablation period,the amount of snow melting was 66. 26 mm,and the sublimation amount was 2. 04 mm. The contribution of net radiation to snow material loss reached 83. 1%,the contribution of the turbulent flux was 16. 9%. Because the soil heat flux was positive during the melting period,the contribution of soil heat flux on snowmelt was zero.