Experimental studies on the long period changes of air-surface energy exchanges

地表与大气之间的能量交换是全球大气过程的重要环节之一。以往关于大气-地面相互作用的研究大多是在晴天条件下进行的，以检验大气湍流理论的结果。然而，为了与气候变化不协调，应评估在大雨或雨天等一般情况下的相互作用过程。本研究的目的是在一般情况下测量大气与地面的相互作用，并检测能量交换的长周期变化。一种是用简单的方法进行远程观测，另一种是用详细的观测来检验它。为实现这一目的，地面辐射温度和地表湿度的连续测量与降雨量、蒸发量和土壤温湿度的测量相结合，形成了利用波瓣桅杆的剖面技术。为了对SIMPLE方法进行详细的观测，采用了涡旋相关法，利用声学风速计-温度计和红外湿度计，结合激光偏转测量空气密度梯度。这些观测是从1986年开始在京都大学Uji地面的南端进行的。对数据的详细分析仍在进行中，包括详细的水分交换分析。其中一些结果发表在报告中。

Energy exchanges between ground surface and atmosphere is one of the important links of global atmospheric processes. Most of the past studies on air-surface interactions were mainly made in fair weather condition to check the results of the theories of atmospheric turbulence. However, to incooperate with climatic changes the interaction processes in general condition such as coludy or rainy days should be evaluated. The purpose of the present study is, on that point, to measure air-surface interactions in general condition and detect long period changes of energy exchanges.For thie purpose, the measurement was devided into two part. One is long range observation in simple method and the other is the detailed observation to check it. For the former purpose profile techniques with lobing mast and continuous measurements of the ground surface radiation temperature and the surface wetness were made together with rainfall, evaporation and soil temperature and humidity measurements. For the detailed observations to check the simple method, the eddy correlation method with the use of the sonic anemoneter-thermometer and the infrared hygrometer together with air density gradient measurement by laser beam deflection is employed.These observations were made on the southern end of the Uji Ground of Kyoto University from 1986. The detailed analysis of the data are still under going including detailed analysis moisture exchanges. Some of the results were published in the report.