学术论文

      塔克拉玛干沙漠腹地地气相互作用参数研究

      Studies of Land-Atmosphere Interaction Parameters in Taklimakan Desert Hinterland

      摘要:
      利用塔克拉玛干沙漠腹地塔中A站2008年7月-2009年7月的连续观测数据,分析了沙漠地气相互作用的几个关键参数。结果表明:(1)地表反照率的计算需选取太阳高度角≥10°的数据,其日均值季节性变化明显,冬季高、夏季低,年均值为0.270±0.003。(2)土壤热容量和热传导率也具有明显的季节变化,冬季值稳定且低而夏季值不稳定且高。平均土壤热容量、热传导率和热扩散率分别为1.559(±0.140)×106 J.m-3.K-1、0.234(±0.021)W.m-1.K-1和1.504(±0.110)×10-7 m2.s-1。(3)地表比辐射率值为0.91。(4)动力学粗糙度远低于国内其他沙漠,值的范围是(2.7~8.0)×10-5 m,比敦煌和黑河试验中的值小2个量级。但在冬季时其值偏大,达到(21.04~91.32)×10-5 m。
      Abstract:
      Continuously observational data collected in Taklimakan Desert hinterland(38°58′N,83°39′E) from July 21,2008 to July 20,2009,have been used to investigate some key parameters of land-atmosphere interaction,including surface albedo,soil thermal parameters and their relationships with soil temperature,and aerodynamic roughness length.The obtained results are as follows:(1) The diurnal variation of surface albedo appears as a 'U' shape on sunny day.It decreases with the increase of solar elevation angle,and it tends to be a constant when solar elevation angle is larger than 10,thus,the daily average surface albedo was computed using the data when solar elevation angle is large than 10.Mean daily surface albedo is found to has obvious season variation,lower in winter but higher in summer,average annual surface albedo is 0.270±0.003.(2) The variations of soil heat capacity and thermal conductivity are becoming lower and more stable during the late autumn to the early spring in next year,and reach the lowest in middle of January.They are lower in winter and higher in summer,also has clear season variations.Average soil heat capacity,soil thermal conductivity and soil thermal diffusion are 1.559(±0.140)×106 J·m-3·K-1,0.234(±0.021) W·m-1·K-1 and 1.504(±0.110)×10-7 m2·s-1,respectively.(3) Surface emissivity,estimated by a physically based,semi-empirical method,is 0.91.(4) Aerodynamic roughness length in Taklimakan Desert hinterland is far less than other domestic deserts,range is(2.7~8.0)×10-5 m,less than 2 orders of magnitude of Dunhuang and Heihe experimental values,but increased to range(21.04~91.32)×10-5m in winter.
      作者: 刘永强 [1] 何清 [2] 张宏升 [3] 艾力·买买提明 [2]
      作者单位: 中国气象局乌鲁木齐沙漠气象研究所,新疆乌鲁木齐830002/新疆大学资源与环境科学学院,新疆乌鲁木齐830046/绿洲生态教育部重点实验室,新疆乌鲁木齐830046/北京大学物理学院大气科学系,北京100871 中国气象局乌鲁木齐沙漠气象研究所,新疆乌鲁木齐830002/塔克拉玛干沙漠大气环境观测试验站,新疆塔中841000 北京大学物理学院大气科学系,北京,100871
      刊 名: 高原气象 ISTICPKU
      Journal: Plateau Meteorology
      年,卷(期): 2011, 30(5)
      分类号: P422.9
      机标分类号: S15 P4
      在线出版日期: 2012年4月21日
      基金项目: 国家自然科学基金项目,中国沙漠气象科学研究基金,绿洲生态教育部重点实验室项目