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Alaska, being the biggest state in the US, comprises an enormous amount of marvelous landforms, which include mountains, volcanoes, uncharted tundra, pristine coastlines and areas covered by permafrost.
A huge amount of mountain ranges is spread throughout the entire territory of Alaska. The most northern mountain range, entitled the Brooks Range, stretches in the west-east direction for 720 miles to the Canadian boarders. The Alaska Range occupies the central, southern and eastern regions and includes Mt. McKinley, the highest point in the United States at 20,320 ft. The St. Elias Mountains, which stretch from the mainland Alaska to the southeast, are the highest coastal range in the world. These and other Alaska mountains (Wrangell Mountains, Coast Mountains, Kenai Mountains and Kuskokwim Mountains) were formed owing to successive collisions of drifting Asian tectonic plates, which took place millions of years ago. Nevertheless, a great number of mountain ranges in Alaska still continue to grow.
There are more than 100 volcanoes throughout Alaska, and nearly 40 of them are active (80% of all active volcanoes in the USA). Ample volcanoes are situated on the Aleutian Islands. They were formed in approximately the same time as the Alaska Range, owing to drifting tectonic plates. After all, the oscillation frequency reduced and the number of eruptions declined. However, despite the fact that the number of eruptions declined since the collusion, volcanoes in the Aleutians continue to erupt every day. Concerning future, the volcanoes in Alaska are not supposed to stop spewing lava.
The North Slope is the most northern part of Alaska and occupies one fifth of the area. The abandoned tundra, which is covered by permafrost most of the year, can be seen here only in the period of Arctic summer. The extremely low amount of precipitation and freezing temperatures make this territory impossible to live in. Most precipitation simply freezes when reaching the ground, and usually does not evaporate, what contribute to permafrost. Nevertheless, this situation in the northern part of Alaska may soon undergo considerable changes. In fact, increase of Earth's average temperature, caused by Global warming, can lengthen the period of Arctic summer, which will lead to the environmental changes of the landform in the future.