A tundra is the region situated near the polar ice caps, with a cold, dry, windy, and icy climate. Tundras can be found in parts of Alaska, Russia, Scandinavia, Iceland, Canada, and Greenland. These places are located in the northern hemisphere, and the regions which should be tundras in the southern hemisphere in fact contain oceans. It is almost impossible for life to exist in a tundra, as the ground is completely frozen over and covered with hard ice.
In these regions, the temperatures rarely go higher than 10 degrees Celsius. During the summer season, some vegetation manages to grow in the form of moss, grass, and other small plants. However, below the active zone, the soil is always frozen which makes it impossible for other vegetation to survive. No matter what happens, this solid ice, known as permafrost, cannot be precipitated. Hence, the vegetation in this part of the world is small, and always remains close to the surface. This place is very safe for migrating birds, as there aren’t too many predators here, making it possible for birds to safely lay their eggs.
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Almost 20 percent of the world's surface is covered by deserts, which are known to be exceptionally hot and dry areas, covered in nothing but sand for miles around. These barren lands usually exist at low altitude; however, there are some deserts which can be found at high altitudes as well, such as the deserts in Utah and Nevada in the USA, and in West Asia. You can find special plants in the desert which are hardy and capable of surviving the bitter heat and climate of this region. There are animals in the desert too, with reptiles being present in abundance. Contrary to common belief, deserts are fertile, which means vegetation can survive here. Only a little bit of rain can result in the growth of trees and plants which require little to no water to flourish. Apart from camels, several other large mammals can also be found in these parts of the world.
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