Atmospheric Radiation Measurement Climate Research Facility US Department of Energy

caps-pmex > Cavity Attenuated Phase Shift Extinction MonitorInstrument Type(s) > Baseline

The cavity attenuated phase shift extinction monitor is an optical extinction spectrometer that measures aerosols, broadband scatterers and absorbers of light that interact with solar radiation and influence the Earth’s radiation balance. The CAPS PMex uses a visible-light-emitting diode (LED), a sampling cell incorporating two high-reflectivity mirrors centered at the wavelength of the LED, and a vacuum photodiode detector.

Primary Measurements


  • Fixed
  • AMF1
  • AMF2
  • AMF3