Atmospheric Remote Sensing: Instruments

Depolarization and Backscatter Unattended Lidar (DABUL)


CSD and the University of Maryland - Baltimore County's Physics Department collaborated to develop and deploy a long-term, unattended infrared spectroradiometer and lidar to monitor and study the radiative effects of water vapor, aerosols, and thin clouds in the upper troposphere. The infrared spectro-radiometer measures atmospheric emitted spectral radiance over the wavelength range of about 3-23 micrometers, while the lidar detects clouds and aerosol layers.

Research applications include:

  • Cloud Geometry
  • Cloud Phase
  • Aerosol Scattering Ratio
  • Extinction Profiles
  • Optical Depth
  • Mixed Layer Height

Basic parameters measured:

  • Molecular and Particle Backscatter
  • Depolarization Ratio

DABUL operates automatically from within weatherproof housing, with remote control access and data download through a communications link.

Typical Specifications

Wavelength523 nm
Pulse energy25 µJ
Pulse rate2000 Hz
Average Time:1 to 10 s
Scan180 ° in elevation angle
Range Resolution:30 m
Minimum range60 m
Maximum range40 km

Field Projects

Project NameDateLocation
Nauru99199906June - July 1999Tropical Western Pacific
Barrow Haze Study199902February - March 1999Barrow, Alaska
SHEBA199710October 1997 - September 1998Arctic Ocean
FIRE-ACE199804April - July 1998Arctic Ocean
SURFRAD199707June - July 1997Boulder, Colorado
Erie Observations199706June 1997Erie, Colorado


Eberhard, W.L., R.A. Alvarez, J.M. Intrieri, S.P. Sandburg, K.W. Koenig, and K.R. Healy, Automated All-Weather Lidar with Scanning Option, 19th International Laser Radar Conference, NASA/CP--1998--207671/PT1, 639-642, Annapolis, Maryland, July 1998.

Alvarez, R.J., W.L. Eberhard, J.M. Intrieri, C.J. Grund, and S.P. Sandberg, A depolarization and backscatter lidar for unattended operation in varied meteorological conditions, 10th Symposium on Meterological Observations and Instrumentation, Phoenix, AZ, 11-16 January 1998. American Meterological Society, Boston, MA, 1998.

Grund, C.J., and S.P. Sandberg, Depolarization and Backscatter Lidar for Unattended Operation, 18th International Laser Radar Conference, 3-6, Berlin, Germany, July 1996.