When you hear the word "arctic," you probably think of ice. Arctic ice is going away. It is melting faster than ever before. In the summer of 2007, about 552 billion tons of ice melted. That is a lot of ice cubes!
Scientists study the melting ice. They use satellites. They study one area called the Greenland Ice Sheet. It covers about 80% of Greenland. This ice sheet is made up of many layers of snow. The snow was pressed together for over one hundred thousand years. The ice looks blue-green in the winter. It looks white in the summer.
Many scientists are surprised by how much ice is melting. The melting is caused by global warming. Global warming means the air around the surface of Earth is getting warmer. Some scientists think that if a lot of ice melts, the sea levels could rise. This could cause problems for cities along the coastlines. It could cause trouble for island countries. Scientists are working hard to solve this problem.