Really shaunehunter?
Being a Canadian you must know how extensive the melting was in the 1850s when difficult to maneuver sailing ships nearly made it through the Northwest Passage? While the sea ice melted, on shore the permafrost was not so permanent then either.
Surely you know that the Canadian military established extreme northern military bases and harbors in the mid 1800s that they are now considering reopening for the first time since WW II.