Total Carbon Column Observing Network these include The satellite missions supported by the TCCON include the Greenhouse Gases Observing Satellite (GOSAT), SCIAMACHY, and the Orbiting Carbon Observatory-2 (OCO-2). Total Carbon Column Observing Network The Total Carbon Column Observing Network (TCCON) is a global network of instruments that measure the amount of carbon dioxide, methane, carbon monoxide, nitrous oxide and other trace gases in the Earth's atmosphere. The TCCON ( ) began in 2004 with the installation of the first instrument in Park Falls, Wisconsin, USA, and has since grown to 23 operational instruments worldwide, with 7 former sites. The TCCON is designed to investigate several
ExoMars Trace Gas Orbiter be a strong indication that biological processes are involved. However, if methane is found in the presence of gases such as sulfur dioxide (), that would be an indication that the methane is a byproduct of geological processes. The nature of the methane source requires measurements of a suite of trace gases in order to characterise potential biochemical and geochemical processes at work. The orbiter has very high sensitivity to (at least) the following molecules and their isotopomers: water (), hydroperoxyl (), nitrogen dioxide (), nitrous oxide (), methane (), acetylene (), ethylene (), ethane (), formaldehyde (), hydrogen cyanide