MORE PROOF THAT COSMIC RAYS - AND NOT MAN-MADE CO2 - CAUSE GLOBAL WARMING

NATIONAL POST (Hat tip TJR):

Dr. Shaviv not only believes there are credible "other suspects," he believes that at least one provides a superior explanation for the 20th century's warming.

"Solar activity can explain a large part of the 20th-century global warming," he states, particularly because of the evidence that has been accumulating over the past decade of the strong relationship that cosmic- ray flux has on our atmosphere. So much evidence has by now been amassed, in fact, that "it is unlikely that [the solar climate link] does not exist."

The sun's strong role indicates that greenhouse gases can't have much of an influence on the climate -- that C02 et al. don't dominate through some kind of leveraging effect that makes them especially potent drivers of climate change. The upshot of the Earth not being unduly sensitive to greenhouse gases is that neither increases nor cutbacks in future C02 emissions will matter much in terms of the climate.

Even doubling the amount of CO2 by 2100, for example, "will not dramatically increase the global temperature," Dr. Shaviv states. Put another way: "Even if we halved the CO2 output, and the CO2 increase by 2100 would be, say, a 50% increase relative to today instead of a doubled amount, the expected reduction in the rise of global temperature would be less than 0.5C. This is not significant."

The evidence from astrophysicists and cosmologists in laboratories around the world, on the other hand, could well be significant. In his study of meteorites, published in the prestigious journal, Physical Review Letters, Dr. Shaviv found that the meteorites that Earth collected during its passage through the arms of the Milky Way sustained up to 10% more cosmic ray damage than others. That kind of cosmic ray variation, Dr. Shaviv believes, could alter global temperatures by as much as 15% --sufficient to turn the ice ages on or off and evidence of the extent to which cosmic forces influence Earth's climate.

In another study, directly relevant to today's climate controversy, Dr. Shaviv reconstructed the temperature on Earth over the past 550 million years to find that cosmic ray flux variations explain more than two-thirds of Earth's temperature variance, making it the most dominant climate driver over geological time scales. The study also found that an upper limit can be placed on the relative role of CO2 as a climate driver, meaning that a large fraction of the global warming witnessed over the past century could not be due to CO2 -- instead it is attributable to the increased solar activity.

CO2 does play a role in climate, Dr. Shaviv believes, but a secondary role, one too small to preoccupy policymakers.

... Dr. Shariv, an astrophysicist who made a name for himself assessing the movements of two-billion-year-old meteors.

AND HE SAYS MAN-MADE CO2 IS NOT A MAJOR FACTOR. RTWT.

BTW: TAB 1ST POSTED ON COSMIC RAYS AND GLOBAL WARMING HERE ; January 6, and again HERE, on January 21.