Leading scientists were critical on Tuesday of the G8's stance on global warming, saying its pledge was too vague and too distant to brake the oncoming juggernaut of climate change. Experts acknowledged the Group of Eight's usefulness in setting a goal of at least halving worldwide greenhouse gas emissions by 2050. But, they complained, the G8 statement did not mention a base year by which this 50-percent cut would be compared.
Nor -- more importantly -- did it identify what cuts would be made in the next decade, a period critical for determining whether the fight against climate change will succeed or fail.
"It is a pretence that they understand the problem and plan to take needed actions," said James Hansen, one of the major figures in the history of climate science. "In reality, they are taking actions that guarantee that we deliver to our children climate catastrophes that are out of their control."
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Cedric Philibert, a French expert at the International Energy Agency (IEA) in Paris, said one of the biggest problems was that these gases had an inertial effect. Even if all emissions were stopped today, the warming would continue for a number of years because of the build-up of existing gas concentrations. "It takes between 15 and 20 years for any change to take effect," said Philibert.
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http://www.terradaily.com/2007/080708161117.t7yv3mav.html