Abstract
As a sequel of the author's previous paper on the diurnal variation of upper wind, wind data at 4km level over Japan were analyzed and it was found that the diurnal rotation of upper wind vector is systematic both in latitudinal and seasonal change, and closely related with the seasonal variation of solar declination.
The diurnal variation of typhoon movement was detected, as is the case with upper wind. Also the correlation of diurnal amplitude of typhoon movement with sunspot number was investigated and some positive correlation was found.
It was concluded, as the result, that the diurnal variation of typhoon may be caused by that of upper wind.
