热物理性质的差异是不同地面类型能量交换差异的物质基础。通过对青藏高原北麓河地区工程地面(沥青路面、砂砾路面)和自然地面(天然地表、高寒草原、高寒草甸)气象参数的观测与计算,分析地表温度、反照率、粗糙度和总体输送系数之间的差异。研究结果表明:夏秋季节沥青路面昼夜温度均高于其他地面类型,春冬季节沥青路面夜间温度高于其他地面类型;砂砾路面、高寒草原、高寒草甸白天表面温度差异约为2℃~5℃,夜间差异为1℃~3℃;天然地表的反照率大于沥青路面,反照率受太阳高度角和降水影响,随太阳高度角增加呈指数递减,在降雨时地面反照率有增有减,降雪增加地面反照率,降水后介质湿度增加,反照率减小;5种地面类型的粗糙度从大到小依次为砂砾路面、天然地表、沥青路面、高寒草甸、高寒草原;粗糙度的大小间接反映地面的能量输送能力,冬季天然地表输送系数大于其他地面类型,在其他季节,天然地表和沥青路面的动量输送系数较大,其次为高寒草原、高寒草甸、砂砾路面。
The differences of thermal-physical properties is the material basis of energy exchange differences for different ground types. The physical properties of the parameters was observed and calculated through the observation and calculation of the physical properties of engineering pavement (asphalt and sand pavement) and natural ground surface (natural surface, steppe and meadow) in Beiluhe permafrost area on the Qinghai-Tibet Plateau, the differences between surface temperature, albedo, roughness and transfer coefficients were analyzed. The results show that in summer and autumn day and night temperatures of asphalt pavement are higher than that of other ground types and in spring and winter the temperatures at night are higher than of the other ground types. Difference of surface temperatures of sand pavement, alpine steppe and alpine meadow is about 2℃ to 5℃ in daytime, and 1℃ to 3℃ at night. The albedo of the natural surface is greater than that of the asphalt pavement. Albedo was affected by solar elevation angle, rain, or snow conditions. According to the roughness, the sequence decreasingly of the five ground types are sand pavement, natural surface, asphalt pavement, alpine meadow, and alpine steppe. The roughness reflects the energy transmission capacity of ground indirectly. In winter, transfer coefficients of natural surface are larger than the other ground types. In other seasons, the momentum transfer coefficients of the natural surface and asphalt pavement are lager, followed by grassland, meadow, gravel. 2 tabs, 5 figs, 16 refs.