- OTTAWA - A prominent University of Ottawa science professor says what
we know about global warming is wrong -- that stars, not greenhouse gases,
are heating up the Earth.
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- Jan Veizer says high-energy rays from
distant parts of space are smashing into our atmosphere in ways that make
our planet go through warm and cool cycles.
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- The retired professor (he still holds
a research chair and supervises grad students and post-doctoral fellows)
knows that to challenge the accepted climate-change theory can lead to
a nasty fight. It's a politically and economically loaded topic. Yet, he
is speaking out -- a bit nervously -- about his published research.
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- "Look, maybe I'm wrong," he
said in an interview. "But I'm saying, at least let's look at this
and discuss it.
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- High-energy cosmic rays are hitting us
all the time. This has been known for a long time. What's new is that a
variety of researchers are asking what cosmic rays do to our world and
its weather.
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- That includes a theory published last
year by the Proceedings of the Royal Society arguing cosmic rays "unambiguously"
form clouds and affect our climate.
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- Prof. Veizer is a leader in geochemistry
-- learning about Earth's past by the chemistry preserved in rocks and
sediments. The Royal Society of Canada called him "one of the most
creative, innovative and productive geoscientists of our times."
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- He won the 1992 Gottfried Wilhelm Leibniz
Prize, worth $2.2-million, the German government's highest prize for research
in any field.
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- Yet, for years he held back on his climate
doubts. "I was scared," he said. And he still is.
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- Still, he has published his theory in
Geoscience Canada, the journal of the Geological Association of Canada.
The article is called "Celestial Climate Driver: A Perspective from
Four Billion Years of the Carbon Cycle."
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- In his paper, he concludes: "Empirical
observations on all time scales point to celestial phenomena as the principal
driver of climate, with greenhouse gases acting only as potential amplifiers."
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- The majority of climate scientists still
firmly believe that greenhouse gases are to blame.
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- But Prof. Veizer felt uncomfortable with
the idea that high levels of carbon dioxide alone are causing hot spells.
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- He looked to geology. As environmental
conditions change, different "isotopes" of some chemicals form.
These are slightly different forms of any element -- carbon, or oxygen,
or less common substances such as beryllium. And these remain frozen in
time in ancient rocks, or lake and ocean sediments, or glaciers. (Samples
drilled from Antarctic ice go back more than 700,000 years, layer by layer.)
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- For Prof. Veizer, the idea is that cosmic
rays hit gas molecules in the atmosphere and form the nucleus of what becomes
a water vapour droplet. These in turn form clouds, reflecting some of the
sun's energy back to space and cooling the Earth.
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- Yet the numbers of cosmic rays vary.
Most come from younger stars, which are clustered at some regions in the
galaxy through which our solar system has passed its 4.5-billion-year history.
As well, our own sun deflects some of these rays away, but the sun's activity
grows stronger and weaker. All these factors can change the number of cosmic
rays that hit us.
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- © National Post 2006
- Copyright © 2006 CanWest Interactive,
a division of CanWest MediaWorks Publications, Inc.. All rights reserved.
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