Total Carbon Column Observing Network

{| class=infobox width=270px |Regions ||Global|- |Instrumentation ||Bruker 125HR spectrometer |- |Software ||GGG2014 / GGG2020 |- |Sites ||23 (2015) |- |Primary Gases (columns) ||| CO₂, CH₄, CO, N₂O, HF, H₂O |}

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 things, including the flow (or flux) of carbon between the atmosphere, land, and ocean (the so-called carbon budget or carbon cycle). This is achieved by measuring the atmospheric mass of carbon (the airborne fraction). The TCCON measurements have improved the scientific community's understanding of the carbon cycle, and urban greenhouse gas emissions.

The TCCON supports several satellite instruments by providing an independent measurement to compare (or validate) the satellite measurements of the atmosphere over the TCCON site locations. The TCCON provides the primary measurement validation dataset for the Orbiting Carbon Observatory (OCO-2) mission, and has been used to validate other space-based measurements of carbon dioxide. Provided by Wikipedia