Arctic GPS is impossible.

The first barrier to GPS being reliably available in the Arctic is due to the orbital inclination of the satellites involved. The satellites follow one of six orbital planes, all at an inclination of roughly 55 degrees, though some other satellite navigation systems, specifically Galileo and Glonass, have higher inclinations of 56 and 64.8 degrees, respectively. The Arctic circle, meanwhile, begins at about 66.5 degrees north. At these high latitudes, several satellites are still visible at any given time, but they never pass directly overhead. In fact, when using GPS right at the pole, the highest elevation GPS satellite you would see is about 45 degrees above the horizon.

As a result, according to Anna B.O. Jensen and Jean-Paul Sicard in their article "Challenges for Positioning and Navigation in the Arctic", this situation leads to "better horizontal satellite geometry, but worse vertical satellite geometry compared to the situation at mid and low latitudes."

There could be several reasons this is the case. First, typically there are not a lot of people in the polar regions, so orbiting in planes that would make satellites visible may not be the most effective use of resources. Each satellite has to be maintained and replaced occasionally. Since humans mostly populate the regions between 55 degrees north and south, it may have just made sense to focus on this area. Second, launching into polar orbit is also more difficult, requires more energy, and is more expensive. So, overall the cost-benefit analysis may not have been favorable.

Augmentation systems exist that can work in parallel with satellite positioning, but the satellites that operate these systems also tend to be difficult to “see” in the Arctic, since they are in Geo-sync Earth orbit, most likely near the equator.

Finally, the Arctic region experiences a lot of ionospheric activity that fluctuates in intensity based on the solar cycle. Every 11 years, there is a rise in ionospheric activity which can produce beautiful aurora borealis but also causes a lot of problems with electronics in general.

GPS satellites are not impervious to ionospheric activity, which can cause signal scintillation, creating changes in the amplitude or phase of signals. This can cause errors in timing, which then translates to errors with positioning calculations.