摘要
利用"内蒙古微气象观测蒸发试验"的观测资料,对6种地表土壤热通量计算方法(Plate Cal法、TDEC法、谐波法、热传导对流法、振幅法和相位法)进行比较,检验了6种方法在不同干湿地表状况下的适用性,并研究了6种方法计算地表土壤热通量的差异以及对地表能量闭合度的影响。结果表明:一般情况下,Plate Cal法计算的2 cm土壤热通量与观测值最接近,计算结果的均方差为6.9 W/m2。在不同干湿地表状况下,干燥和降水条件下适合使用Plate Cal法,计算结果的均方差分别为14.0 W/m2和30.1 W/m2;湿润条件下适合使用谐波法,计算结果的均方差为21.4 W/m2。6种方法计算的地表土壤热通量存在明显差别,最大相差178.6 W/m2,不同方法计算地表土壤热通量的最大差值超过25 W/m2的时次占样本的96.3%。不同方法计算地表土壤热通量的差异对地表能量闭合度的大小有明显影响,但不影响近地层能量闭合度随湍流混合增强而增大的规律。
Soil heat flux was calculated by using methods such as heat flux plate measurement and calorimetry （PlateCal）, thermal diffusion equation and correction （TDEC）, harmonics, conduction–convection, amplitude, and phase to examine the observations of“Microclimate and Evaporation Experiment in Inner Mongolia”. The authors compared these six soil heat flux calculation approaches and researched their applicability to various surface conditions. Moreover, the authors analyzed their impacts on surface energy balance closure. In general, the PlateCal method was shown to accurately calculate soil heat fluxes at depth of 2 cm with a mean square error of 6.9 W/m2. In different surface conditions, this method is the best approach for calculating soil heat fluxes in dry and rainy conditions, with mean square errors of 14.0 W/m2 and 21.4 W/m2, respectively. The harmonic method is the best approach for calculating soil heat fluxes in wet conditions, with a mean square error of 30.1 W/m2. The largest difference in surface soil heat fluxes calculated by the six methods was 178.6 W/m2. Large differences in surface soil heat flux exceeding 25 W/m2 accounted for 96.3% of the sample. The six soil heat flux calculation approaches can obviously affect the energy closure rate; the energy closure rate increases with an increase in turbulence intensity.
出处
《气候与环境研究》
CSCD
北大核心
2015年第2期177-187,共11页
Climatic and Environmental Research
基金
国家重大科学研究计划项目2012CB956200
国家自然科学基金项目41275019
41075006
关键词
土壤热通量
地表能量平衡
相对垂直湍流强度
Soil heat flux
Surface energy balance
Relative vertical turbulence intensity
