Infrared heterodyne spectroscopy of CO2 in the atmosphere of Mars

Abstract An infrared heterodyne spectrometer with a resolving power of 6 × 10 6 has been used to obtain detailed profiles of the 10-μm absorption lines of CO 2 in the atmosphere of Mars. An analysis of the results with an empirical model atmosphere calculation indicates a nearly pure CO 2 atmosphere with an average surface pressure of 5.2 ± 0.5 mbar in the observed regions, a subsolar surface temperature near 275°K, an atmospheric temperature of 235 to 240°K above the subsolar point, and a lapse rate of 2°K/km.

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