Polar bear lying on ice. Photo courtesy of iStockphoto.
http://www.istockphoto.com/stock-photo-11338922-polar-bear-lying-on-ice-close-to-open-water.php
Climate can change, too. It just happens over long periods of time. A place might have been very different long ago. A cool place might have been warm. A warm place might have been cool. How can we know what the climate was like in the past?
