Gas Flux & Turbulence / Open-Path Eddy-Covariance System
Customizable, Integrated System
Requires as little as 6 W of power
Related Documents WEATHER Related Documents WATER Related Documents ENERGY Related Documents GAS FLUX & TURBULENCE Related Documents INFRASTRUCTURE Related Documents SOIL


The open path eddy covariance systems measure sonic sensible heat flux, momentum flux, and the flux of other scalars between the atmosphere and earth’s surface. The system consists of a datalogger, fast response three-dimensional sonic anemometer, and fast response scalar sensors. An independent measure of temperature and humidity from a slow response sensor is also measured to calculate background meteorological variables. Horizontal wind speed and direction are computed by the datalogger from the three-dimensional measurements of wind made by the sonic anemometer.

Basic OPEC

  • Sonic Anemometer (CSAT3A)
  • Infrared Gas Analyzer (EC150)
  • Integrated Sonic Anemometer and Infrared Gas Analyzer (IRGASON)
  • Datalogger (CR3000)
  • Compact Flash card module (NL115 or CFM100)

Extended OPEC

  • Net Radiation (NR-LITE2)
  • Soil Heat Flux (HFP01SC-L)
  • Soil Temperature (TCAV-L)
  • Soil Water Content (CS616-L)
  • Sensible Heat (FW05)
  • Latent Heat (KH20)
  • Temperature and Humidity Probe (HMP155A-L)


Most of the systems we sell are customized. These systems, however, typically measure the following parameters:

  • Carbon-dioxide flux
  • Water-vapor flux
  • Momentum flux
  • Turbulence intensity
  • Sensible heat flux
  • Three-dimensional wind velocity
  • Sonic temperature
  • Air temperature
  • Barometric pressure

Benefits and Features

  • Customizable system providing a range of measurement options
  • Measurements are temporally synchronized through a common set of electronics
  • Low noise
  • Fully integrated, turn-key system
  • User-selectable output bandwidths
  • Low power consumption; suitable for solar power applications
  • Field Rugged
  • Field serviceable
  • On-board data storage using CompactFlash cards and a memory module
  • Extensive set of diagnostic parameters to warn of questionable data
  • Colocated measurement volumes for both analyzer and anemometer