抄録
Sensible and latent heat flux above a deciduous forest was measured directly by eddy correlation method using a sonic anemometer and a fine thermocouple psychrometer during rainfall. Analizing the power spectum of the wind speed components, the sonic anemometer (Kaijo Denki, WA-200) was considered to have operated well even in heavy rainfall. The fine thermocouple psychrometer had two problems; one was the heating by solar radiation and another was the slow response time. Nevertheless, it was regarded to be accurate enough when used in rainy days with low solar radiation and low fluctuation of air temperature and humidity. The dry-bulb of the fine thermocouple psychrometer was small enough, so it seldome caught rain drops; only one measurement out of 130 was affected by a rain drop. Error in calculated heat flux caused by catching a rain drop on the dry-bulb of the fine thermocouple psychrometer was estimated. Standard error was expected to be 10W m-2 both for sensible and latent heat flux. As a conclusion, the eddy correlation system with a sonic anemometer and a fine thermocouple psychrometer was available for measurement of sensible and latent heat flux during rainfall.
