How much of the earth’s surface is permanently frozen? September 27, 2012 by Pamela Landy · Filed Under: Geography About 20 percent of the earth is under permafrost. This means it has had a temperature below 32 degrees Fahrenheit for over two years. In Siberia, some sections of land are frozen to depths of 5,000 feet. Related PostsWhat were the first frozen foods?When did Lincoln say, “I believe this government can not endure permanently half slave and half free”?How much of the earth is unexplored?What’s the smallest country on earth?How fast does the earth travel around the sun?