Tundra areas are cold regions near the Earth's poles where the ground is permanently frozen. They have very little vegetation and are home to animals like polar bears and Arctic foxes. Full definition
The most extensive forest - tundra areas in North America are located on the Canadian Precambrian Shelf from the Northwest Territories to the Labrador coast. (rstb.royalsocietypublishing.org)
The Finnish Meteorological Institute has participated in a study in which similar tundra areas were divided into three different types of tundra on the basis of climate and vegetation. (en.ilmatieteenlaitos.fi)
In North America these coupled interactions set the stage for changes in ecological processes, already documented, consistent with a biome shift characterized by increased deciduous composition in the interior boreal forest and evergreen conifer migration into tundra areas that are, at the same time, experiencing increased shrub densification. (metlink.org)