Characteristics of semi-derivatives of air temperature variation and their application to "one-point Bowen ratio method"
H. Kiyosawa (1)
(1) Faculty of Bioresources, Mie University, Mie, Japan
Temporal semi-derivatives of air temperature and specific humidity in the atmospheric boundary layer of a Siberian Tundra plain were investigated. They were almost linearly related with their spatial gradients in the vertical direction on a day-to-day basis. The coefficients of linearity were changed remarkably with the strength of diurnal wind velocity and stability. As the ratios of the semi-derivatives of air temperature and those of specific humidity corresponded considerably to the ratios of the spatial temperature gradients and the humidity gradients, Bowen ratio method was applicable with one point temperature and humidity data. Sensible heat and latent heat obtained with the one-point method agreed reasonably well with those with the conventional two-point method.