Alpha Jet
Alpha Jet

The Picarro gas concentration analyzer is an in situ airborne or ground-based sensor manufactured by Picarro, Inc. It uses Wavelength-Scanned Cavity Ring Spectroscopy (WS-CRDS) to measure trace gases such as carbon dioxide, carbon monoxide, methane, and water vapor. For carbon dioxide measurements, the laser within Picarro operates at 1603 nm wavelength, while 1651 nm wavelength is used for methane and water vapor measurements. Picarro has a typical sampling time of 2.5 seconds. Depending on the model, Picarro can also provide measurements of carbon isotopes for gas concentrations.

The Alpha Jet Atmospheric eXperiment (AJAX) is an in situ airborne instrument suite deployed on the Alpha Jet research aircraft. It includes an ozone (O3) monitor, a Picarro greenhouse gas analyzer, a COmpact Formaldehyde FluorescencE Experiment (COFFEE) instrument, and a Meteorological Measurement System (MMS). The O3 monitor, made by 2B Technologies, measures O3 at the 185 nm wavelength within a range of 0-250 ppm and typically samples at 0.5 Hz. The Picarro analyzer uses cavity-ring down spectrometry (CRDS) to measure carbon dioxide (CO2), methane (CH4), and water vapor at 0.3 Hz, operating at 1603 nm for CO2 and 1651 nm for CH4 and water vapor. COFFEE detects formaldehyde (HCHO) at 355 nm with a sampling rate of 1 Hz. MMS records ambient temperature, pressure, and three-dimensional winds at 1 Hz.