Eddy covariance flux measurements started in 2012. The mast (2 m high) is located about 100 m east of Arctic Station in a moist tundra site called Ãsterlien. It is a gentle south sloping area covered by low vegetation/dwarf shrubs. The system consist of a LICOR 7200 IRGA and Gill HS50 sonic anemometer. Data were logged at 10 Hz and fluxes processed on a 30 minutes basis using EddyPro software. The time stamp refer to UTC-3. This data-set holds data from 2012-2018. Two major gaps in the data are caused by instrument failures where instruments were shipped out for repair. A continuation of the flux measurements are found in the file: Gas flux EC1-Smart. At the same site (10 meter north of the eddy covariance mast) there is an automatic weather station; AWS2 (data from this mast are found under the sub-programme-groups: Meteorology, Soils, Snow)