In recent weeks, President-elect Donald Trump has threatened trade wars with Canada and Mexico, mused about taking over Greenland, and talked about bringing the Panama Canal.

Global warming is making both places more important to global shipping and trade. To imagine the kind of future a hotter, dryer climate may bring, and the geopolitical challenges it will create, look no farther than two parts of the world that Donald Trump wants America to control: Greenland and the Panama Canal.