Ice Caps, Thinking Caps: Spelling Out the Global Peril

(Reuters) [excerpts; emphasis added]

- World scientists are aiming to spell out in graphic detail the threat of flooding faced by millions of people from America to Asia as global warming melts the polar ice caps.

A major coordinated study of the Arctic and Antarctic ice sheets intends not only to lay the bald facts before world leaders but offer courses of action. "We want to be more prescriptive," said David Carlson, head of International Polar Year (IPY) starting in March 2007.

The two year study, announced on Wednesday by the International Council for Science (ICSU), will be the first coordinated probe in 50 years of the ice-bound ends of the earth under the onslaught of climate change. ICSU is a non-governmental organization whose members include the national science academies of 103 countries.

"Part of the reason scientists stay in the comfort zone is that they can always say: 'well we don't know enough,'" Carlson told Reuters. "We are going to take away the uncertainty. "If we come out of this and say 'we still don't know enough' then we will not have done our job," he added in an interview.

One estimate says that if the Greenland ice sheet -- the second biggest after Antarctica -- melts completely, sea levels will rise by seven meters and drown vast areas of the world.

But that is nothing compared with the estimated 200 meters that sea levels will rise if all the Antarctic ice melts in the coming thousands of years.

But it is not just rising sea levels that are at stake. The melting of the Arctic ice caps will dilute the salinity of the North Atlantic and slow down the life-giving Gulf Stream current that warms northern Europe.

Apart from ice, the IPY research will focus on big themes such as the northern climate system with a faltering Gulf Stream and thawing permafrost, and the ability of the southern oceans to absorb carbon. "We see the whole event as a real jump," Carlson said. "Instead of more of the same, we want this to be a real focus. Our voice is going to be much stronger."