American Scientist

July-August 2008

Volume: 96 Number: 4

The polar bear on a melting iceberg has become the universal cliché symbolizing global warming, but the penguin, the iconic animal from the opposite end of the Earth, might be just as suitable. On the Antarctic Peninsula—the long arm of land reaching toward the tip of South America—winter temperatures have risen 6 degrees Celsius since 1950, more than anywhere else in the world. The climate shift has had measurable effects on penguins and many other organisms. The lone bird on the cover is an Adélie penguin, a species dependent on sea ice for winter feeding; the population of Adélies on the peninsula is in decline. In recent decades, chinstrap penguins have colonized parts of the peninsula where they had not lived for at least seven centuries. The effects of warming on the entire biological community of the peninsula are described by James McClintock, Hugh Ducklow and William Fraser in "Ecological Responses to Climate Change on the Antarctic Peninsula." Cover photograph by Cara M. Sucher, McMurdo Station, Antarctica.