Robust IR Remote sensing technique of the total column of trace gases including carbon dioxide and methane

Progress on the development of a differential radiometer based upon the Fabry-Perot interferometer (FPI) for methane (CH₄) and carbon dioxide (CO₂) detection in the atmosphere is presented. Carbon dioxide and methane measurements are becoming increasingly important as a component of NASA´s programs to understand the global carbon cycle and quantify the threat of global warming. Methane is the third most important greenhouse gas in the Earth´s radiation budget (after water vapor and carbon dioxide) and the second most important anthropogenic contributor to global warming. The importance of global warming and air quality to society caused the National Research Council to recommend that NASA develop the following three missions^1,2 ASCENDS (Active Sensing of CO₂ Emissions over Nights, Days, and Seasons), GEOCAPE (Geostationary Coastal and Air Pollution Events), and GACM (Global Atmosphere Composition Mission). The importance of CO₂ and methane study is reflected in the successful operation of the Japanese Greenhouse gases Observing Satellite (GOSAT) monitoring those trace gases globally from orbit.