| Summary: | A dual-frequency GPS receiver, GSV4004B, has been installed at Alert, Canada since May 2008 to study the ionospheric variability at a high-latitude location. This Ionospheric Scintillation and TEC Monitor (GISTM) receiver is able to measure amplitude and phase scintillation, and also Total Electron Content (TEC). In addition, a High Frequency (HF) link has been established from Qaanaaq to Svalbard since March 2009 to study the channel characteristics, including Doppler spreads. This study covers from end of May 2008 to February 2011 where it was mostly during the minimum state of solar activity. During the period of where both GISTM and HF data were available (i.e. March 2009-July 2010), data from both links are compared to see any relation between TEC variations and scintillation effects and also Doppler spreads. Data from the GISTM receivers at Svalbard were also utilised. Winter months expectedly show lower mean vertical TEC (VTEC) than in other months. Higher mean VTEC was observed in 2010 that could be related to the increase of solar activity. In 2010, both small and large patches of moderate-high intensity were found to be more than twice as common in February and March than in other months. The difference in the occurrences of small patches between months of the same year was about 1-2% (for low intensity patches) and 1-10% (moderate-high intensity). This difference increased to 1-4% (low intensity) and 1-12% (moderate-high intensity) for large patches. UT dependence can be seen where ~80 large and ~300 small patches were identified ~1000 to 2000 UT from June to October in both 2008 and 2009, and they doubled in 2010. Amplitude scintillations index, S4 were very low where at least ~99% were between 0 and 0.1, which is insignificant. Meanwhile, phase scintillations index, σφ were from 0 to 0.1 rad for at least 93% of the time. The relationship of TEC fluctuations/increase and phase scintillations is complex. There are few events where phase scintillations occurred simultaneously with slant TEC increases, ...
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