California will show America the way on climate change.
Gov. Arnold Schwarzenegger on June 1 signed an executive order for big cuts in emissions of greenhouse gases (GHGs).
"California is going to be the leader in the fight against global warming," he said at the United Nations World Environment Day in San Francisco.
He wants the state to cut GHG emissions to 2000 levels by 2010, to below 1990 levels by 2020, and by 80% below 1990 levels in 2050.
"I say the debate is over," Schwarzenegger said. "We know the science. We see the threat. And we know the time for action is now."
Every would-be leader in the fight against global warming declares that the debate is over. If allowed to continue openly and honestly, after all, the debate might question the wisdom of simplistic responses to complex phenomena.
Because for some the debate isn't over, for example, researchers recently reported that the amount of solar radiation reaching Earth's surface increased greatly during the past 2 decades while global average temperature increased. If so, the phenomenon might be more important than the atmospheric build-up of GHGs as a factor in observed warming.
Why might surface measurements of solar energy be increasing? One possibility is that energy emissions by the sun are increasing. Another is that reductions in air pollution are allowing growing amounts of incoming solar radiation to reach the surface.
Imagine that. Human activity warms the planet, after all. But rather than the widely suspected combustion of fossil fuels, it's progress in cleaning the air that does the most warming.
Leaders in the fight against global warming won't relish the irony. They won't listen to any science that contradicts their political agenda. They want to slash emissions of carbon dioxide. They want to do it now.
So California will lead whoever might follow into a costly and possibly futile response to poorly understood observations about the climate.
Is it worth the sacrifice? Might the possibility of warming causes more significant than greenhouse intensification suggest a different approach?
Don't ask. The debate is over.
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