GEOmon is  a European project, funded under the European Commission's Sixth Framework Programme (It ran from February 2007 to April 2011).

The overall goal of the GEOmon (Global Earth Observation and Monitoring of the Atmosphere) project is to sustain and analyze European ground-based observations of atmospheric composition, complementary with satellite measurements, in order to quantify and understand the ongoing changes. GEOmon is a first step to build a future integrated pan-European Atmospheric Observing System dealing with systematic observations of long-lived greenhouse gases, reactive gases, aerosols, and stratospheric ozone.