In 1991, the Air Quality Department of Finnish Meteorological Institute established an air-quality measuring station in the Pallas-Ounastunturi National Park for long-term measurements of several chemical compounds and physical and meteorological parameters. In 1994, together with the Arctic Research Centre (formerly Sodankylä Meteorological Insitute), Pallas was adopted as part of the GAW programme.
The old station had 36 m2 space for housing analytical equipment. Two 7 m towers are attached to both ends (north and south) of the station building. The towers were electrically warmed to preventclogging of the inlets by ice and snow. The north tower was the main tower, with a line made of acid-proof stainless steel tubing with an inner diameter of 60 mm. The air was continuously drawn through this line with a pump with nominal flow rate of 180 m3/h. Thus the residence time inside the sampling line was short, less than two seconds, All the monitors took their sample air from this manifold, except for the radon monitors, which took their air from the other tower. The exhaust air was led some 50 m east of the station building.
In spring 2001 a new, larger station building was constructed 50 m away from the old station. The new building, having 120 m2 of space, is nearly four times larger than the old one. Moving in to the new station took place in July 2001.