Monday, June 23, 2008


ANDREW C. REVKIN NY TIMES Twenty years ago, James E. Hansen, a climate scientist at NASA, shook Washington and the world by telling a sweating crowd at a Senate hearing during a stifling heat wave that he was "99 percent" certain that humans were already warming the climate. . . To many observers of environmental history, that was the first time global warming moved from being a looming issue to breaking news. Dr. Hansen’s statement helped propel the first pushes for legislation and an international treaty to cut emissions of greenhouse gases. A treaty was enacted and an addendum, the Kyoto Protocol, was added.

Dr. Hansen, 67, plans to give a briefing organized by a House committee and say that it is almost, but not quite, too late to start defusing what he calls the "global warming time bomb." He will offer a plan for cuts in emissions and also a warning about the risks of further inaction. . .

Dr. Hansen said the United States must begin a sustained effort to exploit new energy sources and phase out unfettered burning of finite fossil fuels, starting with a moratorium on the construction of coal-burning power plants if they lack systems for capturing and burying carbon dioxide. Such systems exist but have not been tested at anywhere near the scale required to blunt emissions. Ultimately he is seeking a worldwide end to emissions from coal burning by 2030.

Another vital component, Dr. Hansen said, is a nationwide grid for distributing and storing electricity in ways that could accommodate large-scale use of renewable, but intermittent, energy sources like wind turbines and solar-powered generators. . .

Dr. Hansen disagrees with supporters of "cap and trade" bills to cut greenhouse emissions, like the one that foundered in the Senate this month. He supports a "tax and dividend" approach that would raise the cost of fuels contributing to greenhouse emissions but return the revenue directly to consumers to shield them from higher energy prices.