Multifilter Rotating Shadowband Radiometer (MFRSR) - IOP
Instrument Categories: Aerosols, Radiometric
General Overview
The multi-filter rotating shadowband radiometer (MFRSR) takes spectral measurements of direct normal, diffuse horizontal and total horizontal solar irradiances. These measurements are at nominal wavelengths of 415, 500, 615, 673, 870, and 940 nm. The measurements are made at a user-specified time interval, usually about one minute or less. The sampling rate for the Atmospheric Radiation Measurement (ARM) Program MFRSRs is 20 seconds. From such measurements, one may infer the atmosphere's optical depth at the wavelengths mentioned above. In turn, these optical depths may be used to derive information about the column abundances of ozone and water vapor (Michalsky et al. 1995), as well as aerosol (Michalsky et al. 1994) and other atmospheric constituents.
A silicon detector is also part of the MFRSR. This detector provides a measure of the broadband direct normal, diffuse horizontal and total horizontal solar irradiances. A MFRSR head that is mounted to look vertically downward can measure upwelling spectral irradiances. In the ARM system, this instrument is called a "multi-filter radiometer (MFR)". At the Southern Great Plains (SGP) there are two MFRs; one mounted at the 10-m height and the other at 25 m. At the North Slope of Alaska (NSA) sites, the MFRs are mounted at 10 m. MFRSR heads are also used to measure "normal incidence" radiation by mounting on a solar tracking device. These are referred to as normal incidence multi-filter radiometers (NIMFRs) and are located at the SGP and NSA sites. Another specialized use for the MFRSR is the narrow field of view (NFOV) instrument located at SGP. The NFOV is a ground-based radiometer (MFRSR head) that looks straight up.
IOPs Where the Instrument was Used
Spring 1994 UAV IOP
Southern Great Plains, April 1994Spring Cloud IOP
Southern Great Plains, March 1 - 26, 2000
Primary Measurements Taken
The following measurements are those considered scientifically relevant. Refer to the datastream (netcdf) file headers for the list of all available measurements, including those recorded for diagnostic or quality assurance purposes.
- Optical depth
- Shortwave narrowband direct normal irradiance
- Shortwave narrowband diffuse downwelling irradiance
Mentor(s)
Gary Hodges
(303) 497-6460
Gary.Hodges@noaa.gov