The Los Gatos Research (LGR) Fast Greenhouse Gas Analyzer (FGGA) provides measurements of methane (CH4), carbon dioxide (CO2) and water vapor (H2O) simultaneously at speeds up to 10 Hz. The analyzer is simple to use, low power and rugged which makes it ideal for a wide variety of field studies of these greenhouse gases. The unique ability of the analyzer to simultaneously measure all three greenhouse gases makes it ideal for eddy covariance flux and chamber flux measurements of these gases.
The analyzer uses LGR’s patented Off-axis ICOS technology, the fourth-generation cavity enhanced absorption technique, which employs a high-finesse optical cavity as the measurement cell. LGR’s technology has many proven advantages over conventional first-generation cavity ringdown spectroscopy (CRDS) techniques. In brief, since the laser beam does not have to be resonantly coupled to the measurement cell (i.e. precise beam alignment is not critical), LGR Analyzers are relatively inexpensive, simple to build, and inherently robust thermally and mechanically. In addition, since LGR’s technology can record reliable absorption spectra over a far wider range of optical depths (absorbance values) compared with CRDS, LGR Analyzers provide measurements over a much wider range of mixing ratios (gas concentrations). Finally, due to the ease and simplicity of recording and quantifying the measured spectra using LGR’s Off-Axis ICOS, LGR Analyzers display the entire absorption spectra to the user in real time allowing for immediate system diagnostics and performance validation.
The Fast Greenhouse Gas Analyzer has an internal computer (Linux OS) that can store data practically indefinitely on its hard disk drive and send real time data to a data logger via the digital (RS232) or Ethernet outputs. As with all LGR analyzers, the Fast Greenhouse Gas Analyzer may be controlled remotely via the internet using suitable “KVM over IP” devices. This capability allows the user to operate the analyzer using a web browser practically anywhere internet access is available. Furthermore, remote access allows bios-level control of the instrument and provides the opportunity to obtain data and to diagnose the instrument operation without being on site.
In addition, the availability of many value-added options extends the abilities of the unit to include measurements of discrete samples (collected in bags or vials, for example) and to automatically handle multiple inlet sources (e.g., from flux towers or distributed sites) for uninterrupted measurements over periods of weeks.
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