黄河源积雪期土壤温湿及冻融特征分析与模拟

利用2017-2018年黄河源地区野外观测站数据,对黄河源区两个积雪期内土壤温湿及冻融特征进行了分析,并与CLM4.5模式模拟的积雪期土壤温、湿度及辐射分量进行了对比,结果表明:CLM4.5能很好地模拟出整个积雪期土壤温度的变化趋势;对不同土壤层在不同冻结阶段土壤含水量的模拟有所差异:在完全冻结阶段,对5cm土壤层含水量模拟偏高,而80cm偏低,对10~40cm土壤层含水量的模拟偏差较小;由于降雪及土壤冻融过程主要发生在积雪期,积雪反照率使得净辐射模拟在降雪时段偏差较无降雪时段略大。

Analysis and Simulation of the Characteristics of Soil Temperature,Soil Moisture and Freezing-Thawing During Snow Cover Duration in Source Region of the Yellow River

Using the data from the field observation station in the source region of the Yellow River from 2017 to 2018, the characteristics of soil temperature, humidity and freezing and thawing during two snow accumulation periods were analyzed and compared with the soil temperature, humidity and radiation components simulated by CLM4.5 model. The results show that CLM4.5 can simulate the change trend of soil temperature well during the entire snow-packing period; the simulation of the soil moisture content of different soil layers at different freezing stages is different: in the complete freezing stage, the soil moisture content is higher in the 5cm soil layer and lower in the 80cm layer. The simulation deviation of the soil moisture content of 10~40cm is small. Because the snowfall and soil freezing and thawing process mainly occur in the snow cover period, the snow albedo makes the deviation of the net radiation simulation during the snowfall period slightly larger than that during no snowfall.