Värriö sub-arctic research station of University of Oulu and University of Helsinki (Värriö)

SMEAR I –station (Station for Measuring Ecosystem – Atmosphere Relations) was built in 1991-1992 at the side of Värriö Subarctic Research Station to monitor the pollution originating from Kola Peninsula. Continuous measurements of trace gases, aerosols, photosynthesis growth of Scots pines and meteorology have been carried on by the University of Helsinki since 1992. The station is located at the northern border of Salla municipality, some 6 km’s from the Russian border and built on top of a 390 m high forested hill. A 16 meter high weather mast is mounted next to the measurement cabin. The closest source area for air pollutants are the mining and metallurgical industry at the Kola Peninsula with the most important point sources being Nikel, Montcegorsk and Zapolyarny, respectively. In addition to the measurements carried on by the University of Helsinki, Finnish Meteorological Institute (FMI) has been measuring both sulphates and heavy metals using filter sampling techniques. Also, respiration and photosynthesis of the soil has been measured campaign wise in the vicinity of the station. Trace gases have been measured at four different levels (2, 6.5, 9 and 15 m) above the ground until recently the three highest sampling levels were taken off. The sulphur dioxide concentration is measured with a pulsed fluorescence analyzer. Nitrogen oxides (most importantly NO and NO2) are measured with an analyzer that is based on chemiluminescence and ozone is measured with a photometric analyzer. Total aerosol concentration has been measured since 1991 and the particle size distribution since 1997. The cut-off diameter of the size distribution measurements was changed from 8 nm to 3 nm in 2003. The total concentration is measured using CPC (Condensation Particle Counter) and the size distribution with DMPS (Differential Mobility Particle Sizer) system. Photosynthesis of Scots pines is measured from living twigs using chambers placed on top of the trees. Also, the growth in width and length are measured. A wide range of meteorological parameters are measured at five different levels (2, 4, 6.6, 9, 15 ja 16 m). Network type: Automatic and manual monitoring of atmosphere and biosphere (incl. SMEAR I –station and synoptic weather observations) as well as tracking and monitoring wide range of flora and fauna (e.g. game, insects and berries).