Atmospheric Remote Sensing: Instruments
Commercial scanning Doppler lidar (HALO)
HALO is a commercial scanning Doppler lidar (StreamLine XR) from HALO Photonics. They are capable of measuring and mapping atmospheric velocity and backscatter with high precision and sampling rate necessary for boundary layer studies important to understanding weather, climate and air quality. They are suitable for long term unattended measurements. Research applications include:
- High spatial temporal and velocity resolution wind profiles
- Boundary layer turbulence and entrainment zone studies
- Flux measurements
- LES model initialization and validation
Basic Parameters Measured
- Range resolved line-of-sight velocity profiles
- Range resolved backscatter intensity
Typical Measurement Scan
- Scan Duration: 15-20 minutes
- PPI scans: 1, 5, 15, 35, 75 degrees
- RHI scans: at 1-2 azimuths
- Vertical Stare: for the remainder of scan duration
Typical Specifications
| Wavelength | 1.5 µm (fully eye-safe) |
| Pulse energy | ~80 µJ |
| Pulse rate | 10 kHz |
| Pulse duration (FWHM) | 350 ns |
| Telescope diameter | 75 mm |
| Range Resolution | 48 m |
| Time Resolution | 2 Hz (5000 pulse averages) |
| Velocity Precision | ~5 cm/s |
| Minimum range | 96 m |
| Maximum range | 10 km (typically 3 km) |
| Platforms | ground |
Field Projects
| Project Name | Date | Location | |
|---|---|---|---|
| DCFlux | Washington D.C. Flux Study | April 2021 - 2024 | Washington D.C. |
| INFlux | Indiana Flux Study | April 2013 - June 2015, January 2016 - March 2019 | Indianapolis, Indiana |
References
Bonin, T.A., B. Carrol, R.M. Hardesty, W.A. Brewer, K. Hajny, O. Salmon, and P. Shepson, Doppler lidar observations of the mixing height in Indianapolis using an automated composite fuzzy logic approach, Journal of Atmospheric and Oceanic Technology, doi:10.1175/JTECH-D-17-0159.1, 2018.