This readme file describes the .STA datafiles provided for the CU v1 Windcube, WC68, that was deployed at CU Skywatch lab from 14 August 2018 to 28 October 2018. For questions, please contact Julie.Lundquist@colorado.edu, 303/492-8932. If you use these data, please contact Julie regarding citations/authorship. This Windcube is a Leosphere/NRG Version 1 Windcube. ------------------------------- Otherwise, Windcube 68 was located at the northeast corner of the SEEC building, Latitude: 40.01 N Longitude: 105.24 W Elevation: 5250 ft (1600 m) Two types of datafiles are provided. *.STA files provide two-minute averages of averaged winds, while *.RTD files provide nominally 1-sec measurements of line-of-sight velocity for individual beams as well as integrated 4-sec averages. For details on the measurement method, please see Rhodes and Lundquist 2013 (https://link.springer.com/article/10.1007/s10546-013-9834-x) and Lundquist et al. 2015 (https://www.atmos-meas-tech.net/8/907/2015/amt-8-907-2015.html). The filename, including the Leosphere timestamp, marks the end of the measurement period (the end of a two-minute average for the .STA files and the end of a second for the .RTD files). The .STA data files provide two-minute averages of wind speed and wind direction at ten vertical levels. The given timestamp marks the end of the two-minute averaging period. Note that the "u" and "v" as defined in these files are NOT in meteorological coordinates, but rather in engineering coordinates: U positive from north -> south V positive from east -> west W positive from up -> down Therefore, u_meteorological = -v_native v_meteorological = -u_native w_meteorological = -w_native The useful header starts on line 57 and the data start on line 58. The ten altitudes are defined in line 14. Date/Time: DD/MM/YYYY HH:MM:SS UTC Wiper Count: ignore unless suspect precipitation (but often poor metric for precip) Tm: internal temperature (deg Celsius) of the laser unit ****** begin series of quantities that will repeat for each of ten heights ********** Vhm1: mean scalar averaged horizontal wind speed (m/s) at the first (lowest) measurement altitude for the 2-min period dVh1: standard deviation of scalar averaged horizontal wind speed (m/s) VhMax1: maximum 1-sec wind speed measurement during the 2-minute period (m/s) VhMin1: minimum " " Azim1: vector-averaged wind direction of altitude 1 um1: average u-component at altitude 1 du1: standard deviation of u-component at altitude 1 vm1: average v-component at altitude 1 dv1: standard deviation of v-component at altitude 1 wm1: average w-component at altitude 1 dw1: standard deviation of w-component at altitude 1 CNRm: average CNR for the two-minute period (dB); *** we often use -17 dB as a threshold dCNR: standard deviation of CNR CNRmax: maximum CNR CNRmin: minimum CNR spectral_broadening: 2 minute averaged spectral broadening (converted to m/s) dspectral_broadening: standard deviation for previous value Avail.1: percentage of data available at this altitude (assuming CNR threshold of -22 dB) ****** Repeats for next 9 levels The .RTD data files provide 1-sec averages of line-of-sight velocity as well as 4-sec integrations. The header consists of the first 55 lines. The altitudes are listed on line 14. Date/Time: (first column) DD/MM/YYYY HH:MM:SS UTC (except for the offset for one WC) Position: (second column) beam angular position with respect to North (0°). East is +90°, South is +180° and West is +270° Tm: (third column) internal temperature (deg Celsius) of the laser unit Wiper : (fourth column) ignore unless suspect precipitation (but often poor metric for precip) CNR: Carrier to Noise ratio (dB) in the beam line-of-sigh RWS: Radial Wind Speed (m/s) RWSD: Averaged Doppler Spectrum width converted into m/s Vh: Horizontal wind speed (m/s) Azi: Wind direction (degrees, meteorological coordinates) u: wind coordinates along the x-axis (m/s) (this x-axis is oriented north to south, NOT meteorological u) v: wind coordinates along the y-axis (m/s) (this y-axis is oriented east to west, NOT meteorological v) w: wind coordinates along the z-axis (m/s) (w is oriented along the vertical axis and points down) (repeats CNR-->w for next nine levels) Date Position Temperature (°C) Wiper CNR-1 RWS-1 RWSD-1 Vh-1 Azi (°)-1 u-1 v-1 w-1 CNR-2 RWS-2 RWSD-2 Vh-2 Azi (°)-2 u-2 v-2 w- 2 CNR-3 RWS-3 RWSD-3 Vh-3 Azi (°)-3 u-3 v-3 w-3 CNR-4 RWS-4 RWS D-4 Vh-4 Azi (°)-4 u-4 v-4 w-4 CNR-5 RWS-5 RWSD-5 Vh-5 Azi (°)-5 u-5 v-5 w-5 CNR-6 RWS-6 RWSD-6 Vh-6 Azi (°)-6 u-6 v-6 w-6 CNR-7 RWS-7 RWSD-7 Vh-7 Azi (°)-7 u-7 v-7 w-7 CNR-8 RWS-8 RWSD-8 Vh-8 Azi (°)-8 u-8 v-8 w-8 CNR-9 RWS-9 RWSD-9 Vh-9 Azi (°)-9 u-9 v-9 w-9 CNR-10 RWS-10 RWSD-10 Vh-10 Azi (°)-10 u-10 v-10 w-10