Will temperatures on Earth be dropping until the year 2100 to Little Ice Age levels, as Horst-Joachim Lüdecke, a scientist at Germany's Saarland University, predicted last week? Or will the temperatures only plunge until 2060, as Habibullo Abdussamatov, the head of Russia's Pulkovo Observatory, recently predicted? Or has the cooling already begun, and might it end as soon as 2030, as claimed by Anastasios Tsonis, head of the Atmospheric Sciences Group at the University of Wisconsin?
These scientists and others who are now warning of global cooling have something basic in common -- unlike scientists who warn of global warming, who often rely on the Earth sciences and blame climatic change on man-made carbon dioxide, the global cooling scientists more often rely on meteorology, solar science and other disciplines that view the Sun, cosmic rays and Earth's orbit as the dominant factors in our climate.
"The Sun, not man, warms the Earth," an earlier article by Lüdecke, concisely expresses the emergent view that humans play an inconsequential role in climate change. The accumulation of evidence from scientists relying on celestial rather than man-made explanations for changes to the global climate has led even the BBC, an ardent advocate of the man-made global warming theory, to credit the Sun.
"Real risk of a Maunder Minimum 'Little Ice Age,'" stated a BBC headline in October, in reporting the view of Mike Lockwood, Professor of Space Environment Physics at Reading University's Meteorology Department, that "solar activity is now falling more rapidly than at any time in the last 10,000 years."
By the standard of recent years, global cooling predictions and natural explanations for climate change are controversial, even outlandish. By the broader standard of the last century of science -- and the centuries that preceded it -- what's outlandish is attributing massive changes in climate to increases in carbon dioxide, a trace gas that represents so miniscule a fraction of our atmosphere that it must be measured in parts per million. Established science had historically held natural forces to drive climate.
The about-face in the established science came not from a change in the science but from a change in the establishment, in the form of the United Nations bureaucracy. When the UN created the Intergovernmental Panel on Climate Change in 1988, it was mandated to examine man-made causes. This mandate led the IPCC to refuse to consider the Sun's influence on Earth's climate as a topic worthy of discussion, as scientists learned at a 1992 IPCC meeting of delegates from around the world. To the surprise of the Danish delegation's Eigil Friis-Christensen, head of the Danish Meteorological Institute's geophysics division, he was not allowed to present the findings of a peer-reviewed article he had co-authored in Science magazine that compellingly correlated sunspots and global temperatures.
Only evidence of man-made climate change would be considered by the IPCC, he and the others in attendance were then told. And for all intents and purposes, he soon learned, only research into man-made causes would in future be funded, published and given credibility. Friis-Christensen and others conducting research into the role of the Sun found their work ridiculed, marginalized and starved of funding. To a remarkable degree, the IPCC establishment succeeded in controlling which works would be accepted for publication, which careers would be assured and which would be cut short.
What the IPCC couldn't control was the climate. Although carbon dioxide emissions have continued their ceaseless rise, temperatures have not followed along in lockstep, as the global warming models had predicted. Instead, temperatures peaked in the late 1990s and have since plateaued at those levels. Even advocates of the global warming hypothesis - including James Hansen, Al Gore's guru -- acknowledge that global temperatures stopped rising.
The global warming scientists -- with their models defunct and now acting on hope rather than science -- assert that temperatures will soon renew their climb. The global cooling scientists assert the opposite - that temperatures on Earth have peaked, as they have peaked countless times before in following nature's cycles. And that consistent with Earth's history, and with the laws of physics, temperatures on Earth will now be falling.
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