One of the main factors that limits
life on the tundra is the cold average temperature.
The D1 weather station
at Niwot Ridge, Colorado is located on an alpine ridge at 12,264 feet (3,739
meters). The average year-round temperature there is only 25°F (-3.9°C)!
That's as cold as the average year-round temperature at Nome, Alaska (near
the Arctic Ocean.)
Temperatures get warm enough for
plants to grow for only three months or less each year.
Look for ways that plants and
animals have adapted to the cold temperatures above treeline on the alpine