| Using the meteorological data (wind speed, direction, temperature, humidity, visibility, etc.) collected by the German weather service (DWD) over the last 5 years and turbulence measurements recorded by multiple ultrasonic sensors (sampled at 10 Hz) during the past two years, we show that the Umweltforschungsstation Schneefernerhaus (UFS) located at a height of 2700m on the mountain Zugspitze is a well-suited station for cloud-turbulence research. The wind at UFS is dominantly in the east-west direction and nearly horizontal. During the summer time (July and August), there is about 25% of the time that the UFS station is immersed in warm clouds, which are either in the formation process, as moist air rises up from the valley in the east, or strongly convective as being advected by the wind from the west. Wind turbulence, as measured from the second and third order velocity structure functions that exhibit well-developed inertial ranges, possesses Taylor microscale Reynolds numbers between 1500 and 3500. In spite of the complex topography, the turbulence appears to be close to isotropic when evaluated on the so-called "Lumley-triangle". Moreover, no appreciable difference in wind turbulence was observed when the station was covered by clouds. |
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