The results of a feasibility study conducted to determine the possibility of passively measuring the vertical profile of carbon monoxide in the troposphere on a global basis are presented. The instrument considered is a nadir-viewing gas correlation filter radiometer (GCFR). The basic instrument concept and radiative transfer equations are presented. The calculated signal functions, signal levels, sensitivity, and system noise levels of a spaceborne GCFR instrument are presented and discussed. It is concluded that a three- or four-level measurement of the atmospheric carbon monoxide mixing ratio in the troposphere is possible with this type of instrument.
Henry G. Reichle, Jr., H. Andrew Wallio, and Barbara B. Gormsen, "Feasibility of determining the vertical profile of carbon monoxide from a space platform," Appl. Opt. 28, 2104-2110 (1989)