Eddy-covariance systems have long been one of Campbell Scientific’s key offerings. Over the years we’ve worked hard to provide better measurements and a higher level of system integration for this specialized application. Our newest product, the IRGASON, is a continuation of these efforts. As its name suggests, the IRGASON is an infrared gas analyzer (IRGA) and 3D sonic (SON) anemometer combined into a single sensor. Designed specifically for eddy-covariance flux measurements, the IRGASON is the only commercial sensor on the market that simultaneously measures absolute carbon dioxide and water vapor densities, air temperature, barometric pressure, three-dimensional wind speed, and sonic air temperature.
Traditionally, turbulence and gas measurements are provided by two separate instruments mounted close to each other. If these sensors are too far apart, the flux is underestimated, and a variable lag is introduced that depends on the wind speed and direction. The IRGASON avoids these problems by measuring turbulence and CO2 and H2O densities in the same volume. If a traditional gas analyzer is mounted too close to a sonic anemometer, it distorts the wind measurements. The IRGASON integrated sensor provides less wind distortion than two separate sensors. With a common set of electronics, the gas analyzer and sonic anemometer measurements are also temporally synchronized. This avoids flux error due to timing jitter between a separate anemometer and gas analyzer.
The IRGASON is field rugged. It is tolerant to window contamination, and the IRGA optics feature angled windows to better shed water. Easy access to chemical bottles makes it serviceable in the field. Very low power consumption minimizes flux errors due to body heating and makes solar-powered applications more economical and convenient.
The EC150 CO2/H2O Open-Path Gas Analyzer and CSAT3A 3D Sonic Anemometer will continue to be sold for situations where separate turbulence and gas measurements are desired.
With the two principal eddy-covariance measurements now combined into a single instrument, the IRGASON brings a new level of integration to our open-path eddy-covariance systems. The IRGASON provides truly simultaneous and colocated measurements, reduced flow distortion, and easier installation for most eddy-covariance applications.