Comments to this question point out that diversions and emergency landings are not the same.
Many flights between Europe and North-America pass over (very) high latitudes and cold climates such as Greenland and northern Canada. How common are diversions such as this one? Or, more specifically, out of all scheduled passenger flights between Europe and North America, how many are diverted to high latitude airports? For the purpose of this question, I am considering incidents where passengers were forced to leave the plane and change to one or more other planes, rather than a flight that lands and takes off again continuing to its final destination without passengers deplaning.