Global Warming Theory So Simple A Caveman Can Understand It
By STEWART TRUELSEN, American Farm Bureau Federation
Friday, July 20, 2007 8:15 AM MDT
There's a new theory of global warming that is so simple even a
caveman can understand it.
Of course, a caveman would worry more about ice ages, but let's assume
for a moment that global warming concerned him too.
If a caveman thought the Earth was warming up, he had two obvious
theories to choose from. Perhaps it was due to his increasing use of
fire. The other possibility was the big orange disk in the sky, the
Even to the caveman this was a no-brainer. The fire he used for warmth
and cooking was nothing compared to the heat of the sun.
Fast-forward to today and our choices of theories to explain global
warming are more numerous and complex, but not that totally different.
The popular theory is that carbon-dioxide and other greenhouse gases
are warming the atmosphere. Carbon dioxide is formed in the burning of
fossil fuels among other things. Therefore, the cause is largely
attributable to human activity.
But a Danish scientist, Henrik Svens-mark, thinks the sun is playing
the major role in global warming.
In the July 2007 Discover magazine, Svensmark, who is director of the
Center for Sun-Climate Research at the Danish National Space Center in
Copenhagen, blamed the sun and cosmic rays for altering cloud
His basic idea is that the sun can make the sky more or less cloudy.
In the Discover interview, Svensmark said, "And if the sun and the
solar wind are very active - as they are right now - they will not
allow so many cosmic rays to reach the Earth. Fewer cosmic rays mean
fewer clouds will be formed, and so there will be a warmer Earth."
The simplicity of this theory belies the work that Svensmark and his
colleagues have done on it. They've spent years ex-perimenting in a
chamber that produced all the effects they needed to test the theory.
In the end, Svensmark decided that climate is determined by the clouds
and not the other way around.
This doesn't mean that Svensmark completely dismisses greenhouse
gases, because he doesn't. He just thinks that carbon dioxide
emissions are affecting climate change much less than is popularly
thought. And the climate models that are the root of most dire
predictions cannot model clouds so they are really poor, in his
The article's author, Marion Long, said there is really no greater
scientific heresy today than questioning the warming role of CO2, but
Svensmark's theory is disturbing in another way as well.
If he is right, there is really little that can be done about global
Some of the harshest criticism of the Danish scientist's work seems to
be coming out of the United Nations. An even-handed new book on
climate change admitted that the effect of clouds is "complex and not
For agriculture and the rest of us, there is no escaping the debate
over global climate change. Farmers are concerned about international
environmental treaties, new regulations, added layers of bureaucracy
and the inevitable cost, and what if the science behind it is wrong or
A caveman could have shrugged the whole thing off, but we can't.
"[The] 70-90 year oscillations in global mean temperatures [correlate] with
corresponding oscillations in solar activity. Whereas the solar influence is
obvious in the data from the last four centuries, signatures of human
[influence] are not distinguishable in the observations."
Dr. K. Lassen, Danish Meteorological Institute, Solar-Terrestrial Physics