The Ice Man

posted: 4:47 PM, November 1, 2007 - est

When global-warming experts want to come in out of the cold, they turn to Konrad Steffen.

In the middle of a table in Konrad Steffen's office at the University of Colorado at Boulder sits a strikingly beautiful globe made of hand-carved gemstones. Steffen, a geography professor, knows very well that sooner or later the globe will have to be revised. The coastline will shift, swallowing the Nile River megadelta, flooding low-lying expanses of Bangladesh, encroaching onto the Florida panhandle.

On the globe, the changes will be a difference of millimeters, but on a worldwide scale, they could mean the displacement of tens of millions of people. One of the main reasons: the Greenland ice sheet, a gargantuan expanse of ice roughly the size of the Gulf of Mexico, is melting — and it's doing so faster than anyone imagined.

Over the past few years, the ice sheet spewed 250 gigatons of ice into the ocean, or "two and a half times all the ice in the Alps," Steffen says, turning the globe and planting his finger in the center of Europe.

Last month, former vice president Al Gore and the UN Intergovernmental Panel on Climate Change won the Nobel Peace Prize for drawing attention to global warming. Earlier this year, the UN panel had published a report concluding that human influences were likely to blame for planet-wide climate change. The report warned that as rising temperatures melted glaciers and ice sheets and caused the oceans to swell through thermal expansion, sea levels would rise between 18 and 59 centimeters by 2100.

But Steffen, known to everyone as Koni, believes the Greenland ice sheet is deteriorating faster than predicted by these models. By the end of the century, he says, the oceans could rise by roughly three feet.