Atmospheric CO2, CH4, and CO with CRDS technique at the Izaña Global GAW station: instrumental tests, developments and first measurement results [Discussion paper]

In 2015, a CO2/CH4/CO CRDS was installed at the Izaña station (Tenerife). We present the acceptance tests and the processing of raw data applied through novel numerical codes. The ambient measurements performed, and their comparison with other continuous in situ measurements are shown. We determine: a slight CO2 correction that takes into account changes in the inlet pressure/flow rate; the H2O correction for CO in a novel way; and the origin of the CRDS-flow inlet pressure and H2O dependences. The acquisition of the instrument was largely financed by European ERDF funds through the Spanish R+D infrastructure project AEDM15-BE-3319 of the Spanish “Ministerio de Economía, Industria y Competitividad”