HSRL Overview
The NCAR High Spectral Resolution Lidar (HSRL) is an eye-safe calibrated lidar system that can measure backscatter cross-section, extinction, and depolarization properties of atmospheric aerosols and clouds. The system can be deployed on the NSF/NCAR HIAPER GV aircraft. It is installed in the front of the GV cabin and occupies slots for four instrument racks. The lidar points either up or down (in the aircraft coordinate frame) and can be changed during flight.
Number of available systems: 1
Configuration: NSF/NCAR HIAPER GV aircraft
Not available for ground based operations. See MPD for ground based HSRL options.
Observational limits:
- Resolution: 7.5 m x 0.5 second [range x time]
- Maximum Range: 10 km or optical depth exceeding 1.0
- Minimum Range: 350 m
- Wavelength: 532 nm
- Data Products:
- Cloud and aerosol backscatter coefficient (10^-7 to 10^-3 m^-1 sr^-1),
- Cloud and aerosol depolarization,
- Cloud extinction (15 m x 1 second resolution, 10-4 to 10^-1 m^-1)
- Look angle: Either Up or Down. Changed manually during flight operations.
- Cloud and aerosol data products: Backscatter coefficient, depolarization
- Cloud only data products: Extinction coefficient, optical depth
- Data capture resolution: 7.5 m (range) x 0.5 sec (time)
- Wavelength: 532 nm (Green)
NCAR High Spectral Resolution Lidar (HSRL) Contact
Science: Matt Hayman / mhayman@ucar.edu / (303) 497-1087
Data: eol-datahelp@ucar.edu
| HSRL Specifications | |
| Wavelength | 532 nm |
| Pulse Repetition Rate | 4000 Hz |
| Average Power | 300 mW |
| Range Resolution - minimum | 7.5 m |
| Telescope Diameter | 40 cm |
| Field of View (FOV) | 0.025° |
| Temporal Resolution - minimum | 0.5 sec |
| Receiver Channels - 4 | Molecular, Combined Hi, Combined Low, Cross-polarization |
| Iodine Blocking Filter Bandwidth | 1.8 GHz |
| Etalon Filter Bandwidth | 8.0 GHz |
| Typical data variables | ||
| Variable | Unit | Description |
| time | s | Seconds since start of file |
| range | m | |
| Aerosol_Backscatter_Coefficient | m-1 sr-1 | Calibrated measurement of aerosol/cloud backscatter coefficient. |
| Particle_Linear_Depolarization_Ratio | Theoretically determined linear depolarization of particles (molecular removed). Depolarization is measured using circular polarizations and converted to the linear depolarization ratio assuming the volume consists of randomly oriented particles. | |
| Particle_Linear_Depolarization_Ratio | m-1 | Aerosol extinction coefficient |
| Optical_Depth | Total optical depth from aircraft altitude | |
| Temperature | K | Ideal atmosphere temperature |
| Pressure | Pa | Ideal atmosphere pressure |