Next up is Juliet Eilperin, documenting the increasing worry among experts about global-warming "tipping point" scenarios.

While scientists remain uncertain when such a point might occur, many say it is urgent that policymakers cut global carbon dioxide emissions in half over the next 50 years or risk the triggering of changes that would be irreversible.

There are three specific events that these scientists describe as especially worrisome and potentially imminent, although the time frames are a matter of dispute: widespread coral bleaching that could damage the world’s fisheries within three decades; dramatic sea level rise by the end of the century that would take tens of thousands of years to reverse; and, within 200 years, a shutdown of the ocean current that moderates temperatures in northern Europe.

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Irreversible changes, in the next few decades. Whee!

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Eilperin also touches on the political pressure being put on Hansen, and digs up this deliciously Orwellian quote:

Mary L. Cleave, deputy associate administrator for NASA’s Office of Earth Science, said the agency insists on monitoring interviews with scientists to ensure they are not misquoted.

“People could see it as a constraint,” Cleave said. “As a manager, I might see it as protection.”

Yes, Dr. Hansen, this is for your own good. Now please relax — it’s easier when you don’t struggle …

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