Exactly. You can use the Climate Reports to lasso areas away from urban centres in the map:

http://whitemagicsoftware.com/software/climate/guru.shtml

The site says nothing about global warming or the cause. The site does show that there is a consistent warming trend over summer months across all of Canada, and is most extreme in northern Canada. Also, I believe the Environment Canada data is accurate to within 0.2 degrees C.