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21 Feb 08 - Contrary to conventional wisdom, the real danger facing
humanity is not global warming, but more likely the coming of a new Ice
Age.
What we live in now is known as an interglacial, a relatively brief
period between long ice ages. Unfortunately for us, most interglacial
periods last only about ten thousand years, and that is how long it has
been since the last Ice Age ended.
Entering a new ice age would be catastrophic for the continuation of
modern civilization.
One has only to look at maps showing the extent of the great ice sheets
during the last Ice Age to understand what a return to ice age
conditions would mean. Much of Europe and North-America were covered by
thick ice, thousands of feet thick in many areas and the world as a
whole was much colder.
The last Little Ice Age started as early as the 14th century when the
Baltic Sea froze over followed by unseasonable cold, storms, and a rise
in the level of the Caspian Sea. That was followed by the extinction of
the Norse settlements in Greenland and the loss of grain cultivation in
Iceland. Harvests were even severely reduced in Scandinavia And this was
a mere foreshadowing of the miseries to come.
By the mid-17th century, glaciers in the Swiss Alps advanced, wiping out
farms and entire villages. In England, the River Thames froze during the
winter, and in 1780, New York Harbor froze. Luckily, the decrease in
solar activity that caused the Little Ice Age ended and the result was
the continued flowering of modern civilization.
Five hundred million years ago, carbon dioxide concentrations were over
13 times current levels; and not until about 20 million years ago did
carbon dioxide levels drop to a little less than twice what they are
today.
It is possible that moderately increased carbon dioxide concentrations
could extend the current interglacial period. But we have not reached
the level required yet, nor do we know the optimum level to reach.
So, rather than call for arbitrary limits on carbon dioxide emissions,
perhaps the best thing the UN’s Intergovernmental Panel on Climate
Change and the climatology community in general could do is spend their
efforts on determining the optimal range of carbon dioxide needed to
extend the current interglacial period indefinitely.
NASA has predicted that the solar cycle peaking in 2022 could be one of
the weakest in centuries and should cause a very significant cooling of
Earth’s climate. Will this be the trigger that initiates a new Ice
Age?
We ought to carefully consider this possibility before we wipe out our
current prosperity by spending trillions of dollars to combat a
perceived global warming threat that may well prove to be only a
will-o-the-wisp.
Gerald Marsh is a retired physicist from the Argonne National Laboratory
and a former consultant to the Department of Defense on strategic
nuclear technology and policy in the Reagan, Bush, and Clinton
Administration.
See entire article:
http://www.winningreen.com/site/epage/59549_621.htm
Thanks to Hans Schreuder for this link
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