Abstract
To study wind characteristics in complex terrain, we installed three dimensional sonic
anemometers at 67 m and 45 m above ground level in Iwaya wind park of Aomori prefecture in Japan.
High resolution analysis of wind direction shows that the flow distortion arises along the undulating
topography. Absolute values of vertical wind speeds observed at lower observation point are more or less
larger than those at higher point, which is dependent on wind directions. The difference of vertical flow
between different heights would relate to increase of the wind shear and the turbulent intensity. Due to
such flow characteristics and large roughness on the ground, the turbulent intensity seems to be larger
than IEC category A, in the wide range of wind direction keeping steep slope and complex topography.
