北京大学学报(自然科学版)

热对流对土壤温度和能量平衡的影响

孔丽静1, 刘树华1, 吕世华2, 张宇2   

  1. 1. 北京大学物理学院大气与海洋科学系,北京 100871; 2.中国科学院寒区旱区环境与工程研究所, 兰州 73000;
  • 收稿日期:2010-03-22 出版日期:2011-05-20 发布日期:2011-05-20

Effect of Thermal Convection on Soil Temperature and Energy Balance

KONG Lijing1, LIU Shuhua1, Lu Shihua2, ZHANG Yu2   

  1. 1. Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871; 2. Cold and Arid Regions Environmental Engineering Research Institute, Chinese Academy of Science, Lanzhou 73000;
  • Received:2010-03-22 Online:2011-05-20 Published:2011-05-20

摘要: 在传统的土壤热传导方程基础上,耦合了土壤水分的垂直运动引起的热对流项, 用金塔绿洲 2005年6月11? 15 日的观测数据分别计算了土壤热扩散系数以及水的通量密度。以0.05 m 深度的土壤层为上边界,模拟了 0.10m 和 0.20m 深度的土壤层温度,并比较了计算的地表能量闭合因子。结果表明:热传导对流方法模拟的土壤温度与实际观测值吻合较好,且热对流作用使土壤表面能量闭合因子提高 6%左右。

关键词: 热传导, 热对流, 土壤热扩散率, 水通量密度, 能量闭合因子

Abstract: The authors coupled the heat convection caused by water vertical movement to the traditional soil heat conduction equation. Utilizing the data collected at Jinta Oasis from June 11 to 15, 2005, the thermal diffusivity and the liquid water flux density were calculated respectively. Based on the results of soil thermal diffusivity, taking the soil layer at the depth of 0.05 m as the upper boundary, the authors modeled the temperature for the soil layer at the depth of 0.10m and 0.20m by means of the two methods mentioned above, and compared the surface energy closure factor which calculated by the two methods. The results show that the thermal conduction-convection algorithm can estimate the soil temperature well and the role of thermal convection can improve the soil surface energy closure factor 6% or so.

Key words: thermal conduction, thermal convection, soil thermal diffusivity, water flux density, energy closure factor

中图分类号: