The cosmic rays group affiliated with the Space Physics and Astronomy Research Unit and Sodankylä Geophysical Observatory (both of University of Oulu, Finland). The main research topics include (but not limited to) variability of cosmic rays (galactic cosmic rays, solar energetic particles), their atmospheric effects, space climate phenomena and corresponding variability of solar activity. The group has great expertise in numerical modelling of interaction of energetic particles and atmosphere, but also conducts an experiment in ground-based measurements of cosmic ray variability at two sites: Oulu (Finland) with a 9NM64 neutron monitor and a muon telescope and Concordia Station (Antarctica) with a double mini neutron monitor.