京都市近郊における大気境界層乱流 --冬季集中観測結果--

Abstract

Intensive observations of turbulence in the atmospheric boundary layer (ABL) during the winter season were conducted in the suburbs of Kyoto City. In the afternoon, strong winds in the lower ABL were intermittently observed by Doppler lidar. Radiosonde observations suggest that turbulent mixing in the ABL extends the high-speed layer, which is located in the upper levels, toward the lower position. Large-scale turbulence structures with temporal scales of more than 100 s were detected in the time series of the streamwise velocity component measured by sonic anemometer. The occurrence of large-scale structures is likely related to the intrusion of the high-speed layer toward the surface.