GV-HSRL Measurements and products

The GV-HSRL provides real-time, calibrated vertical profiles along a single line of sight of various atmospheric parameters such as cloud optical depth, aerosol optical depth, backscatter coefficient, extinction coefficient, and particle depolarization (spherical irregularity). The HSRL technique uses an independent backscatter channel that observes only molecular scattering to act as a calibration target at each range bin. This allows the retrieval to remove effects of the instrument and atmospheric transmission in backscatter coefficient retrievals. The molecular backscatter is also leveraged to obtain an estimate of extinction. The primary data products for scientific use are listed below.

Variable Unit  

time

s

Seconds since start of file

range

m

Range from instrument

Aerosol_Backscatter_Coefficient

1/(m sr)

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.

Aerosol_Extinction_Coefficient

1/m

Aerosol extinction coefficient

Optical_Depth

 

Total optical depth from aircraft altitude

Temperature

K

Ideal atmosphere temperature in K

Pressure

Pa

Ideal atmosphere pressure in Pa

Data example

GV-HSRL example of aerosol backscatter and depolarization ratio.