%0 Journal Article %T 那曲地区土壤冻融过程对地表能量通量的影响研究
Effect of Soil Freezing and Thawing Process on Surface Energy Flux in Naqu Area %A 王庆语 %J Advances in Geosciences %P 1409-1426 %@ 2163-3975 %D 2022 %I Hans Publishing %R 10.12677/AG.2022.1211138 %X 为了研究那曲地区土壤冻融过程的土壤水分和热量变化特征,及土壤冻融过程对地表能量通量的影响。本文利用国家青藏高原科学数据中心的青藏高原地气相互作用过程高分辨率(逐小时)综合观测数据集中BJ站2013年5月1日至2014年5月31日的观测数据,将土壤冻融过程划分为冻结过程、完全冻结、融化过程和完全融化四个阶段,通过分析不同冻融阶段陆面关键参量的季节和日变化特征,从而获得土壤冻融过程对地表能量通量的影响特征。结果表明:1) 感热通量、波文比(β)和能量闭合率(CR)明显受土壤冻融影响,在冻结过程中,由于土壤冻结地表反照率增大,感热略有增大,而净辐射和潜热减少,则波文比在该阶段增大。土壤液态水冻结释放热量,土壤降温速率受到抑制,地表热通量(G0)被高估,CR大于1;在融化过程中,土壤湿度增大,潜热变大,波文比减小。土壤融化吸收热量,减缓了土壤的增温速率,地表热通量G0被低估,CR则小于1。2) 土壤温度在不同冻融阶段平均日变化基本一致,而土壤湿度平均日变化差异较大,在完全融化阶段土壤湿度变化平缓,但在冻结过程和融化过程中土壤湿度变化幅度较大,夜晚土壤湿度小,白天土壤湿度大,与地表土壤日冻融过程“昼融夜冻”一致。辐射通量白天达到最大值。净辐射(Rn)、感热(H)、潜热(LE)和土壤热通量(G0)日变化相同,均为白天大晚上小;波文比平均日变化在完全冻结阶段 > 融化阶段 > 完全融化阶段 > 冻结阶段;CR在夜间接近于0,在白天接近于1。
In order to study the change characteristics of soil moisture and heat during soil freezing and thawing process in Naqu area, and the influence of soil freezing and thawing process on surface energy flux, based on the observation data of BJ station from May 1, 2013 to May 31, 2014 collected from the high-resolution (hourly) comprehensive observation data of the Tibetan Plateau geo-atmosphere interaction process in the National Qinghai-Tibet Plateau Scientific Data Center, the soil freezing and thawing process is divided into four stages: freezing process, complete freezing, melting process and complete melting. By analyzing the seasonal and diurnal variation char-acteristics of key land surface parameters in different freezing and thawing stages, the influence characteristics of soil freezing and thawing process on surface energy flux are obtained. The results showed that: 1) sensible heat flux, Bowen ratio (β) and energy closure rate (CR) were significantly affected by soil freezing and thawing. During the freezing process, due to the increase of soil surface albedo, sensible heat slightly increased, while net radiation and latent heat decreased, Bowen ratio increased at this stage. Soil liquid water freezing released heat, soil cooling rate was inhibited, surface heat flux (G0) was overestimated, CR > 1. In the melting process, soil moisture increases, latent heat increases and Bowen ratio decreases. Soil melting absorbs heat and slows down the soil warming rate. The surface heat flux G0 is underestimated and CR is less than 1. 2) The average daily variation of soil temperature in different freezing and thawing stages is basically the same, but the average daily variation of soil moisture is quite different, and the change of soil moisture is gentle in the complete thawing stage, but the change of soil moisture is large in the freezing process and thawing process. The soil moisture at night is small and the soil moisture %K 土壤冻融,地表能量通量,季节变化,能量闭合,波文比
Soil Freezing and Thawing %K Surface Energy Flux %K Seasonal Variation %K Energy Closure %K Bowen Ratio %U http://www.hanspub.org/journal/PaperInformation.aspx?PaperID=58421