The vast tundras are treeless, and the coldest of the biomes. They cover nearly 20% of the Earth’s surface, and are noted for having cold and windy climates that receive very little rain. There are two different types of tundras: The arctic tundra and the alpine tundra.
The arctic tundra is located at high latitudes, like Alaska and Russia. The average temperature sits around -18° F during winter, one of only two seasons there. Also in winter, there are days when the sun never makes an appearance. During the summer, which is 50-60 days in length, the sun is present for nearly 24 hours a day. Compared to other biomes, the arctic tundra has a relatively low diversity of plants and animals, due to its’ harsh climate, although some additional animals migrate here during the summer days. Permafrost – permanently frozen ground – is present in the arctic tundra. Warming global temperatures put the permafrost in danger of melting. If this begins to happen, it releases carbon stores, and begins to emit greenhouse gases, further warming the atmosphere.
Alpine tundras are found in mountain regions all over the world. Unlike arctic tundras, alpines do not have permafrost. The winter in the alpine tundra lasts from October to May, with average temperatures below freezing. The months of June to September are the summer, and the average temperatures are 50° to 60° F. Due to the high altitude of the alpine, and resulting low air pressure, plants and animals have had to adapt in order to sustain.