Environmental Data: Snow Drift Station - 3D Ultrasonic

Sonic wind component u

The data contains values for u direction of the wind in a sampling frequency of 20 Hz. Erroneour spikes were filterd in two steps. 1. Define moving window uₓ = u(i-3:i+3) 2. If u(i)-mean(uₓ) > 2*std(uₓ):u(i) = NaN Frozen detectors resulted in continuous zero values (not filtered). The wind speed and direction were calculated as follows: wind speed = sqrt(u² + v²) wind direction = 180° + (180° / PI)* arctan2 (-u, -v)

Sonic wind component v

The data contains values for v direction of the wind in a sampling frequency of 20 Hz. Erroneour spikes were filterd in two steps. 1. Define moving window uₓ = u(i-3:i+3) 2. If u(i)-mean(uₓ) > 2*std(uₓ):u(i) = NaN Frozen detectors resulted in continuous zero values (not filtered). The wind speed and direction were calculated as follows: wind speed = sqrt(u² + v²) wind direction = 180° + (180° / PI)* arctan2 (-u, -v)

Sonic wind component w

The data contains values for w direction of the wind in a sampling frequency of 20 Hz. Erroneour spikes were filterd in two steps. 1. Define moving window uₓ = u(i-3:i+3) 2. If u(i)-mean(uₓ) > 2*std(uₓ):u(i) = NaN Frozen detectors resulted in continuous zero values (not filtered). The wind speed and direction were calculated as follows: wind speed = sqrt(u² + v²) wind direction = 180° + (180° / PI)* arctan2 (-u, -v)

Sonic temperature

The data set contains values of temperature (°C) measured with the anemometer at a sampling frequency of 20 Hz.

Sonic time

The data set contains the time in YYYY-mm-dd HH:MM:SS.sss for the anemometer data. The time is given in UTC+1.