CIMEL Radiometer

Sun-sky automatic radiometer Cimel 318-NE

The Cimel is an automatic radiometer used to monitor aerosol optical properties via sun and sky radiation measurements. This equipment was installed at ALOMAR thanks to the collaboration among the Andøya Space Center (ASC), the Norwegian Institute for Air Research (NILU) and the University of Valladolid (GOA-UVA).
The Cimel is the standard instrument of the AERONET network. It is in operation in ALOMAR since 2006 and the data are archived in AERONET under the site “Andenes”. The calibration of this equipment is carried out by RIMA, federated to AERONET.

It provides aerosol optical thickness at various wavelengths in the range 340 to 1640nm, the Ångström exponent and a set of products derived from inversion procedures, like volume size distribution, single scattering albedo, complex refractive index, etc. See the AERONET web page for further information.

Technical properties:

  • Model 318-NE
  • 9 interference filters, 2 detectors
  • Direct sun: 340, 380, 440, 500, 670, 870, 940, 1020, 1640 nm
  • Sky radiance: 440, 500, 670, 870, 1020, 1640 nm. (almucantar and principal plane)
  • Field of view (sun&sky): 1.2°
  • AOD accuracy: 0.01
  • Radiance accuracy: 3%
  • Sampling period: 15 minutes