On the Increase of Mixing-ratio in the Lower Air Cur ent across Tusima-Strait

Abstract

The north-west monsoon in winter is transformed _??_y the evaporation from the sea surface on the way of travel across Tusima-Strait and the transfomation is shown by the increase of mixing-ratio. We intend to calculate its values when the flow is considered as stationary. As a result, we get mixing-ratio increases, on the average, 0.095gr/kg per hour.
The increase of mixing-ratio is connected most closely with the wind velocity and its increase is proportional to the square root of a certain wind velocity, but when the wind velocity exceeds this range the increase is stopped and maintains almost a constant value on account of the convection and the eddy diffusion.
It is shown that H. U. Sverdrup's formula on the amount of evaporation from the sea surface derived from the theory of boundary layer is very useful from the fact that the amount of evaporation calculated by the above formula is very nearly propor_??_ional to the actual increase of mixing-ratio in case of the large wind velocity.