First, a definition is given for Föhn-type and Bora-type local winds. The Fan is a fall wind on the lee side of a mountain range. When it blows, the air temperature becomes higher than before on the leeward slope. The Bora is also a fall wind on the lee side of a mountain range, but when it begins, the air temperature becomes lower than before on the leeward slope. This definition can be applied regardless of the vertical structure along the cross-section, which is not always easy to observe for every case in the field. Second, the local winds caused by the airflows crossing a mountain range are classified according to the above definition. Third, vertical and horizontal models are illustrated, and descriptions of topography, clouds, precipitation and wind phenomena for the 12 parts from the windward regions to the leeward regions along the cross-section are given in a table.
In the second part of the present paper, the impacts of local winds caused by the airflow crossing a mountain range are discussed. The effects of strong wind on the roofs of houses, wind breaks and hedges in the fields and surrounding houses, agricultural cultivation and land use, and windrelated names of places and passes are striking in the regions with strong fall winds on the leeward part as well as on the passes. Human response to such geographical conditions is quite sensitive, and we are able to know the local distribution of strong winds through observing these responses of the local people.
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