Why isn greenland a continent?
It is not connected to Canada by land but it is part of the North American tectonic plate. The water way that separates it from the North American mainland was carved out by giant glaciers in the last few ice ages. Otherwise, it would probably be attached by a land bridge. The term “continent” is sort of like the term “planet”. As we discovered the world we used the term continent to describe general areas. The recent revision of Pluto to a minor planet or planetoid illustrates that these terms are plastic and can be revised in their use. Along the same lines typically Europe and Asia are today often referred to as the Euro-Asian continent. But it could be more appropriate to refer to the tectonic plates as the ways the land masses should be divided. Ironically this means that a large chunk of eastern Siberia is part of North America plate, and that alone shows that the term continent can mean anything you want it to mean. Greenland is could be called a subcontinent or mini-continent.,
