Narrow Field of View (NFOV) Radiometers Deployed

 
Published: 30 September 2004

The 1-channel (left) and 2-channel (right) NFOV radiometers are collocated with the infrared thermometer (green stripe) at the SGP Central Facility. Numerous other instruments are situated nearby.

In September 2004, the ARM Climate Research Facility Operations staff installed a new 2-channel Narrow Field of View (NFOV) radiometer at the Southern Great Plains (SGP) site. They also installed a repaired 1-channel NFOV radiometer that had been damaged by lightning in June 2002. As reported in August, the 1-channel NFOV measures spectral radiance at 870 nm, while the new 2-channel NFOV measures at both 673 nm and 870 nm. The additional measurement better supports cloud research by the ARM Science Team, particularly in developing cloud optical depth algorithms and retrieval methods for broken cloud fields.

Both NFOV radiometers are now collocated at the SGP site with the Infrared Thermometer that measures brightness temperatures at 10 µm, and are also in close proximity to the microwave radiometer, which measures water vapor and liquid water. Because their fields of view overlap, the various instruments are able to obtain cloud property measurements from the same area in an atmospheric column. The original 1-channel NFOV was deployed to provide a redundant check on data quality for the new 2-channel version; the 1-channel NFOV may eventually be moved to another the ARM Climate Research Facility site.