The meteorological observation has been conducted in order to figure out the actual situation of fog and stratus spread under the inversion layer of Yamase.
Since the advective flow from the Pacific Ocean is intercepted by Mt. Hachiman (1022m high) in Aomori Prefecture, the grazing land which is located on the slope of its eastern side was selected and two fixed observation points were set up: one (100m) is in the grazing land and the other is at the mountain district (880m).
Travelling observations between these two points were also carried out by the car to measure solar radiation and dry and wet bulb temperatures.
During the observation period (June 24-July 2, 1988), one or two layers inversion were recognized under the height of 1, 500m from the aerological data at Misawa.
There is a good correspondence between the vertical profile of air temperature at Misawa and the data of air temperature obtained at two fixed points.
When the depth of the inversion layer is shallow, the most part of the grazing land is above the layer and it has been found out that not only air temperature but also solar radiation is enough to vegetate.
When the depth of inversion layer is deep and the land is in the layer, the solar irradiation is higher along with the altitude, because the radiation path through the fog and stratus is shorter.
