Ground based in situ observations of online_crds at Zeppelin mountain (Ny-Ålesund) (NO0042G). These measurements are gathered as a part of the following projects EMEP, EMEP_NRT, NILU_NRT and they are stored in the EBAS database (http://ebas.nilu.no/). Parameters measured are: carbon_dioxide in air (mass_fraction_of_carbon_dioxide_in_air), carbon_dioxide in air (mass_fraction_of_carbon_dioxide_in_air), carbon_monoxide in air (mass_fraction_of_carbon_monoxide_in_air), carbon_monoxide in air (mass_fraction_of_carbon_monoxide_in_air), methane in air (mole_fraction_of_methane_in_air), methane in air (mole_fraction_of_methane_in_air)