Most scientists are certain that global warming is real. The signs are all around us. Greenland is a large island. It is off the coast of Canada. An ice sheet covers much of it year round. Now its ice is melting. In fact, its loss of ice doubled between 1995 and 2005.
In the whole Arctic Ocean, the amount of ice fell by nine percent from 1978 to 2008. In September 2007, the Northwest Passage was ice-free for the frist time in histroy. The Northwest Passage is a sea route in the Arctic Ocean. It lies above Canada. Since it was never free of ice, ships have not used it.
The ice in the Antarctic is melting, too. Melting polar caps have made the blogal sea level rise four to ten inces in the past 100 years. This has hurt mangrove forests in Bangladesh and Bermuda. Higher sea levels caused saltwater to mix with the fresh water in which these trees grow.
For the last few decades, parts of Canada, Alaska, and Russia have had warmer temperatures. The permafrost has thawed in some places. (Permafrost is soil that should be frozen all the time.) So we know that the world is heating up. the question is, can we stop it? Can we slow it down? Only time will tell.