The tall black-and-white residents of Antarctica, who waddle around its icy landscape, are in peril thanks to the rapidly warming global climate. Emperor penguins go through an annual transformation called catastrophic molting, during which they replace all of their feathers over a short period. This process begins in December and is usually completed before the end of February. During this time, the penguins depend on stable ice to stay warm and dry because the protective coat that normally makes them waterproof and cold-proof is still growing in.