Eleven proxy records of Northern Fennoscandia and North Atlantic climate variability were analyzed. Correlation of climatic records with (a) a quasi 11-year solar cycle of Schwabe, (b) a quasi 22-year solar cycle of Heil, (c) a quasi 20-year planetary-tidal cycle, related to wobbling of the Sun around the baricenter of the solar system, has been studied. A weak but stable and statistically significant correlation between the climatic proxies of Northern Fennoscandia and a double solar cycle was found to be present through the AD 1700–2000. No evidence of a connection between climatic records and both solar Schwabe cycle and quasi 20-year astronomic cycle were found. Possible physical mechanisms behind the revealed effect are discussed.

Neutron monitors (NM64) are standard ground-based detectors that measure the flux of primary cosmic rays at GeV energies in space by counting secondary particles (mostly neutrons) from atmosphere cascades. The atmospheric neutrons are detected by induced nuclear fission in a gas proportional counter. In the standard design, there is a lead ring to generate evaporation neutrons that are moderated by polyethylene before being detected in the 10BF3 gas counter. By omitting the lead, so called “bare counters” respond to lower energy particles on average and can be used in conjunction with NM64 to estimate the energy spectrum of the primary cosmic rays. The specific objective of this research is to refine the understanding of the lead-free neutron monitor now installed at the South Pole using Monte-Carlo FLUKA simulations. This design uses paraffin and wood to moderate high-energy neutrons and detects them with 3He gas-filled proportional counters. Latitude surveys have shown that they have different detection efficiency from either the NM64 or polyethylene moderated bare counters, but they have never been adequately modelled. Understanding the differences quantitatively is the goal of this work. We will also report the detection efficiency of the paraffin bare for other atmospheric particles.

IceTop, the surface component of IceCube Neutrino Observatory at the South Pole, studies cosmic ray air showers with an array of ice Cherenkov detectors typically referred to as “IceTop Tanks.” In November 2009, collaborators from the University of Delaware, UW River Falls, and Uppsala University loaded an insulated shipping container containing an IceTop Tank on the icebreaker Oden which traversed the Atlantic Ocean from Helsingborg, Sweden to McMurdo, Antarctica, and return. Over an approximately 6-month interval, Oden carried the IceTop Tank through a wide range of geomagnetic cut-offs. The data obtained will allow the energy dependent effective area (yield function) to be determined using the Earth as a magnet spectrometer. The ultimate goal of the project is to calibrate the IceTop Tanks to study cosmic rays in the GeV primary energy range. We will report preliminary results for determining the yield functions.