Posted 27 May 2011
"We conclude that atmospheric CO2 levels should be above 150 ppm to avoid harming green plants and below about 5000 ppm to avoid harming people. That is a very wide range, and our atmosphere is much closer to the lower end than to the upper end. The current rate of burning fossil fuels adds about 2 ppm per year to the atmosphere, so that getting from the current level to 1000 ppm would take about 300 years—and 1000 ppm is still less than what most plants would prefer, and much less than either the nasa or the Navy limit for human beings." A clear and layperson-friendly explanation that completely destroys the myth of CO2 as a cause of dangerous global warming, by a physicist who is acknowledged as one at the highest level in USA and the world: William Happer, the Cyrus Fogg Brackett Professor of Physics at Princeton University.
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