Analysing the records of wind vanes at selected places in the valley Kitakami, the author calculates the north and the east components of the winds. After studying their durnal variations the following results were obtained.
In the early morning the land breezes are formed by the down slope winds coming from the Range Kitakami and the Range Ou, situated on both sides of the river. In this valley, these down slope winds occur almost at the same hour. The sea breezes come up along the valley from the mouth of the river. It takes 10 hours for them to travel from the mouth to Morioka, 165 km distance.
The sea breezes shift just as “front”. Accordingly the weather shows a special durnal variation at Morioka. To the north of Morioka, the north components of the winds have two max. and min. a day. It could be thought as an influence of down slope wind on the south ward slope, the top-most part of the valley. And this system of winds prevails about 6 hours later than the land breezes. The height of these down slope winds Is estimated about 400 meters, while the land breezes have the height of 1200-1300 meters. These thicknesses are comparable to the heights of the ranges.
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