Global Warming - A Chilling Possibility

Will it happen again? Researchers are scrambling to find out.

On Feb. 13, an expedition set sail from Great Britain to place current-monitoring sensors in the Atlantic Ocean that will check the Gulf Stream for signs of slowing. The voyage is the latest step in a joint US / UK research project called Rapid Climate Change, which began in 2001. Another international project, called SEARCH (Study of Environmental Arctic CHange), kicked off in 2001 with the goal of more carefully assessing changes in Arctic sea ice thickness.

more The RRS Discovery, on a voyage to measure currents in the Atlantic Ocean.

Much depends on how fast the warming of the Arctic occurs, according to computer simulations by Thomas F. Stocker and Andreas Schmittner of the University of Bern. In their models, a faster warming could shut down the major Atlantic current completely, while a slower warming might only slow the current for a few centuries.

And, inevitably, the discussion turns to people. Does human industry play a major role in warming the Arctic? Could we reverse the trend, if we wanted to? Not all scientists agree. Some argue that the changes occuring in the Arctic are consistent with large, slow natural cycles in ocean behavior that are known to science. Others see a greater human component.

"The sea ice thawing is consistent with the warming we've seen in the last century," notes Spencer, but "we don't know how much of that warming is a natural climate fluctuation and what portion is due to manmade greenhouse gases."

If the Great Conveyor Belt suddenly stops, the cause might not matter. Europeans will have other things on their minds - like global warming that causes concerns as to how to grow crops in snow. Now is the time to find out, while it's merely a chilling possibility.

For more information:

Download 'Artic Meltdown: Rising Seas' TV documentary
http://www.firstscience.com/home/firstscience.tv/arctic-meltdown-rising-seas_4.html

Download 'Meltdown: In the Shadow of Nepal's Lost Glaciers' TV documentary
http://www.firstscience.com/home/firstscience.tv/meltdown-in-the-shadow-of-nepal-s-lost-glaciers_19.html