Space-based measurements of carbon dioxide

There are a variety of active and planned instruments for measuring carbon dioxide in Earth's atmosphere from space.

Even though satellite observations of CO2 are somewhat recent, they have been used for a number of different purposes, some of which are highlighted here: Remote sensing of trace gases has several challenges.

Because these instruments use spectroscopy, at each sounding footprint a spectrum is recorded—this means there is a significantly (about 1000×) more data to transfer than what would be required of just an RGB pixel.

[citation needed] Water vapor can dilute other gases in air and thus change the amount of CO2 in a column above the surface of the Earth, so often column-average dry-air mole fractions (XCO2) are reported instead.

There have been other conceptual missions which have undergone initial evaluations but have not been chosen to become a part of space-based observing systems.