nimfr: Normal Incidence Multifilter Radiometer

The Normal Incidence Multifilter Radiometer (NIMFR) is a ground-based instrument that provides a time series of the shortwave spectral direct normal irradiance. Additionally, a broadband silicon detector can crudely measure the direct normal broadband irradiance.

These irradiance measurements can be used to infer clear sky aerosol optical depth and columnar abundances of ozone and water vapor. The NIMFR is one of a class of instruments known as sun photometers.


  • Fixed
  • AMF1
  • AMF2
  • AMF3

Related Publications


Kassianov E, C Flynn, A Koontz, C Sivaraman, and J Barnard. 2013. "Failure and redemption of MFRSR/NIMFR cloud screening: Contrasting algorithm performance at ARM NSA and SGP sites." Atmosphere, 4(3), 10.3390/atmos4030299.

Koontz A, G Hodges, J Barnard, C Flynn, and J Michalsky. 2013. Aerosol Optical Depth Value-Added Product Report. U.S. Department of Energy. DOE/SC-ARM/TR-129.


Flynn C, DD Turner, A Koontz, D Chand, and C Sivaraman. 2012. Aerosol Best Estimate (AEROSOLBE) Value-Added Product. DOE ARM Climate Research Facility. DOE/SC-ARM/TR-115.


Michalsky J, F Denn, C Flynn, G Hodges, P Kiedron, A Koontz, J Schlemmer, and SE Schwartz. 2010. "Climatology of aerosol optical depth in north-central Oklahoma: 1992–2008." Journal of Geophysical Research – Atmospheres, 115(D7), D07203, 10.1029/2009jd012197.

Ferrare R, C Hostetler, J Hair, A Cook, D Harper, S Burton, M Obland, R Rogers, A Swanson, D Turner, N O'Neill, and P Colarco. 2010. Airborne HSRL Aerosol, Ice, and Cloud Observations During ARCTAS/ISDAC. Presented at Atmospheric System Research (ASR) Science Team Meeting.


Koontz A, D Flynn, G Hodges, J Barnard, E Kassianov, and C Flynn. 2009. ARM Multi-year/Multi-site MFRSR Aerosol Optical Depth Assessment. Presented at Atmospheric Radiation Measurement (ARM) Science Team Meeting.


Voyles JW. 2007. ACRF Instrumentation Status: New, Current, and Future September – October 2007. DOe ARM Climate Research Facility. DOE/SC-ARM/P-07-002.8.

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