摘要：Four new ground-based atmospheric monitoring stations in Finland were examined for local and large-scale signals in carbon dioxide mole fraction, and the results were compared with the corresponding values obtained from WMO/GAW site Pallas, northern Finland and NOAA/ESRL marine boundary layer reference time series. The measurements were filtered with knowledge of local weather and air composition. Periods of a presumably well-mixed boundary layer and relatively pollutant-free air were close to the Pallas time series in mole fraction, particularly in the winter. Wintertime mole fractions were 5–10 ppm higher than the signal in the marine boundary layer at all stations. The seasonal amplitude was 18–24 ppm, and diurnal amplitude was 0–3 ppm in winter and 3–20 ppm in the summer months. All stations, with the possible exception of the urban site in Helsinki, showed potential for observing a large-scale carbon dioxide signal.
