Tonight's guest Henry Willis has examined how weather changes can have a severe effect on the world. One of the most intriguing paradoxes about the current situation is how global warming can actually contribute to what has been called a "New Little Ice Age," which could form in the northern hemisphere. "Earth's climate has changed rapidly in the past and could change rapidly in the future," write Terrence Joyce and Lloyd Keigwin, scientists for the Woods Hole Oceanographic Institution. In their article(1), they lay out how weather changes can be brought on by modifications in the ocean currents.
Known as the "Great Ocean Conveyor," heat in the ocean generally moves from the equator towards both of the poles. When the conveyor system last broke from this pattern (estimated by climatologists to be 12,000 years ago) a dramatic cooling took place. What could be bringing us to that point again may be caused by the increase in fresh water in the North Atlantic Ocean, which normally maintains a saltiness that gives it its density. Melting glaciers and ice (caused by global warming) are bringing more fresh water down into the Atlantic Ocean. This could have the effect of preventing the Gulf Stream from traveling up into the colder waters, thus lowering the temperatures in areas that border the North Atlantic.
But will this effect be as severe as conjectured in "The Coming Global Superstorm(2)," by Whitley Strieber and Art Bell? They write of massive storms, unprecedented rains and blizzards engulfing the Northern Hemisphere. "It would gradually become clear that a catastrophe of breathtaking proportions had occurred...The entire American Midwest would be under a sheet of ice, one that would extend across Siberia and Northern Europe as well," they write. Perhaps we won't face such extreme changes, but scientists do believe that a temperature cooling of a mere five degrees could cause major problems.
--L.L.(3)
1. http://www.whoi.edu/institutes/occi/abruptclimate_joyce_keigwin.html
2. http://www.amazon.com/exec/obidos/ASIN/0671041916/ctoc
3. http://archive.coasttocoastam.com/info/about_lex.html