Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Observations of tropical cirrus properties in the pilot radiation observation experiment using lidar and the CSIRO ARM filter radiometer

Conference ·
OSTI ID:83193
A narrow beam fast filter radiometer has been developed for the Atmospheric Radiation Measurement (ARM) Program. The radiometer is intended to operate alongside a lidar at ARM sites in a lidar/radiometer (LIRAD) configuration. The radiometer detects in three narrow bands at 8.62-, 10.86-, and 12.04-m central wavelengths in the atmospheric window. In addition, it has a variable field aperture that varies the radiance incident on the detector and also allows the field of view to be tailored to that of a lidar used in the LIRAD technique. The radiometer was deployed in the ARM Pilot Radiation Observation Experiment (PROBE) at Kavieng, Papua New Guinea in January-February 1993. The radiometer worked satisfactorily and appeared to be very stable. The radiometer was compared with a previous CSIRO radiometer and the improved performance of the ARM instrument was very evident. The ARM radiometer was also compared with a National Oceanic and Atmospheric Administration (NOAA) Environmental Technology Laboratories (ETL) interferometer and gave closely equivalent radiances. The LIRAD method was used at Kavieng to obtain the optical properties of cirrus clouds. Continuous observations of water vapor path obtained by the NOAA ETL microwave radiometer were employed to allow for the strong tropical water vapor absorption and emission. Cirrus cells that developed on one morning, independent of other clouds, had measured infrared emittances varying from <0.1 to 1.0.
Research Organization:
USDOE Office of Energy Research, Washington, DC (United States). Environmental Sciences Div.
OSTI ID:
83193
Report Number(s):
CONF-940277--; ON: DE95009951
Country of Publication:
United States
Language:
English