Difference Between Tundra And Taiga
The Arctic tundra, the most northerly biome, covers approximately one-fifth of the surface of Earth. Tundra that occurs on the tops of high mountains is known as alpine tundra.
The tundra is a treeless area characterized by permafrost—a layer of permanently frozen ground about 3 feet (1 meter) below the surface. Because of its northern location, conditions are harsh: winters are long and cold, with temperatures dropping as low as −60° F (−51° C); summers are short and relatively cool, with temperatures rarely exceeding 50° F (10° C). Annually, the average temperature ranges between 10° and 20° F (−12° and −6° C).
These temperature ranges cause the top layer of soil (topsoil) to alternately freeze and thaw. In the warmer months, the thawed topsoil and snow create marshy areas, lakes, and streams. The cold temperature also means that organic matter decomposes slowly and water does not drain quickly from the land. As a result, bogs form as layers of decaying plant matter build up and turn into a substance called peat.
Overall, however, the tundra is fairly dry—in fact, it is sometimes called a polar desert. The average annual precipitation (snow and rain) is very low—less than 14 inches (350 millimeters), most of which falls during the warmer part of the year. Although, in winter, the average depth of the snow is not high, strong winds can create frequent blizzard conditions and substantial snowdrifts.
Owing to the extreme northerly location of the tundra, the Sun never sets during part of the summer, and the Sun never rises during part of the winter. The growing season on the tundra is very short—less than 60 days.
South of the tundra lies the taiga, the largest in area of all the biomes. The taiga, which is also called the boreal forest zone and the subarctic zone, occurs in North America, Europe, and Asia, in a belt that stretches around the globe.
As on the tundra, the weather in the taiga is cold, with very cold winters and cool summers. The average temperature in the summer is 50° F (10° C); in the winter, temperatures can drop to −40° F (−40° C) or even lower. The growing season is relatively short, lasting only 50 to 100 days. Precipitation is only slightly more plentiful than in the tundra: an average of 12 to 33 inches (300 to 850 millimeters) per year, mainly as rain in the summer.