Polar Bear, Why Is Your World Melting? (Library Binding)

By Robert E. Wells

Albert Whitman & Company, 9780807565988, 32pp.

Publication Date: September 1, 2008



In the Arctic, the summer ice is melting, making it hard for polar bears to survive. Why is the world getting warmer? The heat of the sun is trapped by the -greenhouse- gases that surround Earth--carbon dioxide, methane, nitrous oxide, and water vapor.