Title:		Horizontal wind speed and direction profiles from Doppler lidar
Location:	Belle Mina Site for Vortex-SE-2016      
Lat/Lon:	34.690 degN, -86.885 degE
Date updated: 	15 August 2016
Contact: 	Dave Turner, NOAA (dave.turner@noaa.gov)
System:  	Halo Streamline lidar, which is part of the CLAMPS-1 facility

--- Background

Doppler lidars transmit pulses of 1.5 um wavelength laser energy into the atmosphere, which scatters off aerosol particles and hydrometeors.  The lidar measures the intensity of this return, as well as its radial velocity.  The lidar has a scanner which allows the system to scan anywhere in the hemisphere, and typically a fixed scan strategy is used.

These data were derived from plane-parallel-indicator (PPI) scans, which were collected approximately every 2 minutes.  In this scan, data were collected at 8 different azimuths each at 70 degrees elevation.  These data were processed using the velocity-azimuth-display (VAD) technique by Dave Turner.  The RMS field in the file indicates the goodness-of-fit to the assumed sine wave, and large values of RMS (e.g., > 2) denote times/heights where the data should not be trusted.  

This dataset was collected north of Belle Mina, Alabama, during the VORTEX-SE-2016 field campaign.  This lidar is the Halo Streamline system, which is part of the Collaborative Lower Atmospheric Mobile Profiling System (CLAMPS-1).  It only operated until 9 March before suffering a failure of its internal computer.

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