Radiance and Irradiance Profiling Radiometers

C-OPS (Compact-Optical Profiling System) is a radiometer system for determining apparent optical properties in aquatic systems. It consists of two 7 cm diameter radiometers: one measures in-water upwelling radiance, and the other either downward irradiance or upward irradiance, pressure/depth, and dual axes tilts. Both radiometers are equipped with up to 19 optical-filter microradiometers (selected from 29 different wavelengths)and are mounted on a unique free-fall, kite-like backplane. To avoid influences from the shadow of the boat or dock, the backplane can be optimized for either slow descent rates for work in very shallow (e.g., 3 m) and coastal waters, or faster descent rates for observations in the open ocean. C-OPS is so lightweight it can be hand deployed by almost anyone, and the system can be operated from either small or large vessels. An above-water surface reference instrument is also available to measure global irradiance. Click here to download brochure.

C-OPS near arctic ice edge. Photo S. HookerC-OPS near arctic ice edge. Photo S. Hooker


  • Complete, integrated system for measuring radiometric variables in coastal waters with submersible and above-water instrumentation (for both turbid coastal and clear oceanic waters);
  • Submersible instruments are optimized for measuring vertical profiles of radiance and irradiance in aquatic systems;
  • Radiometrically matching surface reference system;
  • Based on microradiometer technology with 10 decades of dynamic range;
  • Rapid sampling rates, 15 data frames per second from up to 4 instruments, simultaneously;
  • Free-fall descents with very slow descent rates and adjustable buoyancy;
  • UV capable with optical wavebands down to 305 nm;
  • Ideal for ocean color, satellite calibration and validation, and shallow or deep water research.
  • Highlighted in NASA’s Ocean Ecology Science Research Portal in the Instrument Development section. Click C-OPS to be taken directly to the Portal page.
  • Click here for the chapter dealing with C-OPS from the NASA Technical Memorandum "Advances in Measuring the Apparent Optical Properties (AOPs) of Optically Complex Waters," NASA Tech. Memo. 2010–215856

C-OPS can be customized to fit your specific needs, including the following special configurations:

  • ICE-Pro: a C-OPS free-fall package designed for work though/under ice;
  • C-AERO: Compact-Airborne Environmental Radiometers for Oceanography a 19 wavelength, microradiometer-based radiance and global irradiance instrument system;
  • C-OPS-UV: Compact-Optical Profiling System-Ultraviolet  (replaces PUV-2500/2511) an 8 wavelength (expandable to 19) microradiometer-based profiler, measuring downward cosine ultraviolet irradiance at depth. The C-OPS-UV can be matched with upwelling radiance instrument and/or surface reference instrument;
  • C-PrOPS: The adddition of a Compact-Propulsion Option for Profiling Systems allows a C-OPS profiler to be maneuvered similarly to a remotely operated vehicle, allowing the system to be dynamically positioned away from a boat or shoreline and into the desired sampling location. 
  • Last Updated on Wednesday, 03 October 2018 13:04
    You are here:   HomeC-OPS