Home » Airborne Measurements » Cloud Absorption Radiometer (CAR)
Cloud Absorption Radiometer (CAR)
STATUS
Operational
AVAILABILITY
Has flown since 1982 on numerous aircraft platforms, including the University of Washington B-23, C-131A, CV-580, South African Weather Service Aerocommander 690A, and Sky Research Jetstream J-31 and NASA P-3B.
REQUEST PROCEDURE
Contact Dr. Charles K. Gatebe at NASA Goddard Space Flight Center
Airborne Measurements
An airborne multiwavelength scanning radiometer that measures the angular distribution of scattered radiation deep within a cloud layer, as well as the bidirectional reflectance of land, cloud, and ocean surfaces. It has 14 spectral bands from 0.34-2.30 µm.
CONTACT
Charles K. Gatebe
Universities Space Research Association (USRA)
Goddard Space Flight Center Code 613.2 Greenbelt, MD 20771
(301) 614-6228
charles.k.gatebe@gsfc.nasa.gov
car.gsfc.nasa.gov
SECONDARY CONTACT
Eric Wilcox
NASA Goddard Space Flight Center
Goddard Space Flight Center Code 613.2 Greenbelt, MD 20771 USA
301-614-6409
eric.m.wilcox@nasa.gov
http://car.gsfc.nasa.gov/
SPECIFICATIONS
ManufacturerNASA Goddard Space Flight Center
Dimensions74 cm long, 41 cm wide, and 39 cm deep
Weight42 kg
Power Source TypeAC and DC
Inlet Apertures190° field of view; 1° instantaneous field-of-view.
Heating/Cooling Requirements
Airspeed/Altitude Requirements150 m/s; 200- 8000 m
Operators Required1
Ground Requirements
Suitable PlatformsJetstream J-31/NASA P-3B
Data System14 channels at 16 bit
Measured ParameterRadiance, bidirectional reflectance distribution function
Measurement TechniqueRadiative transfer and light scattering analysis
Operational ModeBRDF, nadir, and zenith scanning modes
Time Resolution100 RPM scanner
Horizontal Resolution10 m (nadir) to 270 m (at 80°) from an aircraft altitude of 600 m
Other Resolution
Precision16 bit
Accuracy2-5% radiometric calibration
Range
Calibration Methodintegrating sphere (GSFC lab)
Limitations
REFERENCES
Gatebe, C. K., M. D. King, S. Platnick, G. T. Arnold, E. F. Vermote, B. Schmid, 2003: Airborne spectral measurements of surface-atmosphere anisotropy for several surfaces and ecosystems over southern Africa, J. Geophys. Res., 108(D13), 8489, doi: 10.1029/2002JD002397. King, M. D., M. G. Strange, P. Leone and L. R. Blaine, 1986: Multiwavelength scanning radiometer for airborne measurements of scattered radiation within clouds. J. Atmos. Oceanic Technol., 3, 513-522.
REMARKS
The CAR instrument was developed at NASA's Goddard Space Flight Center by Dr. Michael King, now retired from NASA. He is currently at Laboratory for Atmospheric & Space Physics, University of Colorado. (michael.king@lasp.colorado.edu)
UPDATED ON
7 Oct 2011 10:02