North Atlantic Tracks question
I recently flew (with Delta) Heathrow - Seattle and return.
On the outward journey, crew announced we are going "way up north today" and our track was over Iceland, Greenland, Northwestern Passages of Canada.
Our return a week later was much further south (south Hudson Bay, south of Greenland etc).
My two questions:
1. Is there a fixed number of North Atlantic tracks available, each one always using the same route/coordinates, or are they more changeable?
2. Was our outward journey unusually far north for this route, or just pretty much bog standard?
Thanx.