I don't have access to a world atlast at the moment, so don't know if Greenland is in the running. There was an article recently in the Christian Science Monitor about agriculture coming back there due to global warming (a subject that ain't theoretical there). As I recall, the article said there are people making a living now growing things like potatoes. Another crop was mentioned but don't remember what it was. When the first settlers arrived back when the world was warmer, there was less ice and good pasturage. After the "Little Ice Age" developed, that all changed. Now, it's becoming green again. Some distant villages that depending on the hunting trade are now collapsing due to lack of ice, and folks are consolidating in some of the bigger towns.

I'm always amazed when I find examples of what I think of as warm-region crops grown someplace colder. In one southern reach of Russia, there's at least some rice grown. I met the manager of the country's only rice mill at a conference several years ago. They evidently buy rice on the world market for the mill, too, but rice has been cultivated in that area for generations, as I understand it.

Shifting, warming weather patterns will likely prompt more of these changes. Now and then, you'll read about someone trying to grow cotton in Nebraska or Delaware. That's getting less far fetched.