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ARCTIC ICE MELTDOWN WILL LEAD TO A GLOBAL FREEZE
As the temperature rises in the Arctic, it could effect the Deep Ocean Current Conveyor Belt which would send a chill around the planet ~ much as it did 12,000 years ago when it all but shut down the Gulf Stream plunging Europe into a 1,300-year deep freeze : Allen L Roland
Having recently re-watched the incredible BBC production of Planet Earth ~ winner of nine Emmys and countless other worldwide awards ~ I was, once again, amazed at both the footage and the responsibility we must assume in maintaining this incredible living organism, our planet. As such, we must be fully aware of the consequences of our continued addiction to fossil fuel ~ for our existence, not the planet's, is at stake.
One of the great merits of the series is that it fully illustrates the huge economic value of the environmental services that nature renders without charge to humanity, e.g., pollinating, cleaning water, cleansing the atmosphere, restoring soil. and stabilizing the climate.
But the lymphatic system of this living organism, Planet Earth, is the deep ocean current conveyor belt which stabilizes the climate throughout the world.
Technically, it is called thermohaline circulation which is the global system of surface and subsurface ocean currents that is driven by temperature and salinity differences that create density gradients between adjoining water masses. Sometimes referred to as the oceanic "conveyor belt," it is responsible for moving great amounts of thermal energy around the globe, both influencing and being influenced by the planet's climate.
With the obvious current melting of the Arctic ice cap ~ it poses dire consequences for humankind if this thermal current did not cool at the artic and sink ~ thus interrupting the vertical circulation at a crucial point in the cycling of heat through the ocean with the potential of, believe or not, a deep freeze that once occurred 12,000 years ago.
Just yesterday ~ it was reported that a four-square-kilometre chunk has broken off Ward Hunt Ice Shelf - the largest remaining ice shelf in the Arctic ~ threatening the future of the giant frozen mass that northern explorers have used for years as the starting point for their treks. Scientists say the break, the largest on record since 2005, is the latest indication that climate change is forcing the drastic reshaping of the Arctic coastline, where 9,000 square kilometres of ice have been whittled down to less than 1,000 over the past century, and are only showing signs of decreasing further. http://www.theglobeandmail.com/servlet/story/RTGAM.20080729.wice29/BNStory/National/
Eugene Linden explains the phenomenon and consequences fully in this excerpt from his excellent article The Big Meltdown.
Allen L Roland http://blogs.salon.com/0002255/2008/07/31.html
THE BIG MELTDOWN
As the temperature rises in the Arctic, it sends a chill around the planet
Eugene Linden
http://www.eugenelinden.com/thebigmeltdown.html
" Even greater climate change could be on the way. Growing numbers of scientists fear that the warming trend will so disrupt ocean circulation patterns that the Gulf Stream, the current that warms large parts of the northern hemisphere, could temporarily shut down. If that happens, global warming would, ironically, produce global cooling ~ and bring on a deep freeze.
Without action, major changes appear inevitable. Should surface water temperatures in the high Arctic rise just a few degrees, the sea ice could disappear entirely, but even a partial melting could devastate the northern hemisphere's climate. A combination of melting ice, increased precipitation and runoff from melting glaciers on land could leave a layer of buoyant freshwater floating atop the denser salt water, at a point in the North Atlantic where water ordinarily cools and sinks. (The Global deep ocean conveyor belt )
The lighter freshwater wouldn't sink, interrupting the vertical circulation at a crucial point in the cycling of heat through the ocean ~ as if you're grabbing this conveyor belt and slowing it down.
So how would that produce cooling?
Ordinarily the conveyor is propelled by the pull created by masses of water sinking in the North Atlantic. When this pull diminishes, the movement of warm water north in the Gulf Stream could slow or stall, driving down temperatures in Europe and North America, and possibly elsewhere.
It has happened before. Roughly 12,000 years ago, at the end of the last Ice Age, a natural warming sent freshwater from melting glaciers flowing out of the St. Lawrence River into the North Atlantic, all but shutting down the Gulf Stream and plunging Europe into a 1,300-year deep freeze. The more that becomes known about this period, named the Younger Dryas (after a tundra plant), the more scientists fear that the rapid melting of sea ice could cause the same catastrophe again. Only next time, writes geophysicist Penn State's Richard Alley in a forthcoming book, Two-Mile Time Machine, the effects would be much greater, "dropping northern temperatures and spreading droughts far larger than the changes that have affected humans through recorded history." Would this be "the end of humanity?" he asks rhetorically. "No," he replies. "An uncomfortable time for humanity? Very."
A sudden chill would shorten growing seasons, and the resulting changes in precipitation could be even more damaging. Colder air is dryer air, and Alley points out that during the Younger Dryas, the monsoon weakened in Asia and the Sahara expanded. Harvey Weiss, a Yale archaeologist who has studied the role of climate in human history, notes that it's not changes in temperature that bring down civilizations but changes in precipitation.
Protecting civilization is the goal of the Kyoto Protocol, but the treaty allows 12 more years for implementation, on the assumption that climate change will be gradual. That assumption looks shaky. Studies of deep underground ice layers in Greenland, which reveal a record of climate changes over hundreds of thousands of years, show that major climate shifts, like the onset of the Younger Dryas, can come very abruptly ~ within a few decades. "
It is increasingly obvious to me that this glorious self sustaining living organism, Planet Earth, will survive regardless of how we mistreat it ~ but we as humans may well not survive unless we unite, consciously evolve and become in sync with nature's interdependent and loving plan.
Allen L Roland http://blogs.salon.com/0002255/2008/07/31.html
Freelance Online columnist and psychotherapist Allen L Roland is available for comments, interviews, speaking engagements and private consultations ( allen@allenroland.com )
Allen L Roland is a practicing psychotherapist, author and lecturer who also shares a daily political and social commentary on his weblog and website allenroland.com He also guest hosts a monthly national radio show TRUTHTALK on www.conscioustalk.net
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