  
                     Years Later, Climatologist Renews His 
                      Call for Action
                          
                    Jun 23, 2008 - Andrew C. Rivkin - The New 
                      York Times 
                          
                   
                    
                       
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                        Oscar Hidalgo for The 
                          New York Times  
                          James E. Hansen, a NASA climate expert, 
                          used a pair of cardboard dice 20 years ago to explain 
                          that humans were tipping the odds of harmful climate 
                          change by adding greenhouse gases to the atmosphere. 
                          He displays one die in his Manhattan office.  | 
                       
                      
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                    Twenty years ago Monday, 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. 
                    “The greenhouse effect has been detected, 
                      and it is changing our climate now,” Dr. Hansen said then, 
                      referring to a recent string of warm years and the accumulating 
                      blanket of heat-trapping carbon dioxide and other gases 
                      emitted mainly by burning fossil fuels and forests.  
                    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. 
                     
                    Even as the scientific picture of a human-heated 
                      world has solidified, emissions of the gases continue to 
                      rise.  
                    On Monday, 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. 
                     “If we don’t begin to reduce greenhouse gas 
                      emissions in the next several years, and really on a very 
                      different course, then we are in trouble,” Dr. Hansen said 
                      Friday at NASA’s Goddard Institute for Space Studies in 
                      New York, which he has directed since 1981. “Then the ice 
                      sheets are in trouble. Many species on the planet are in 
                      trouble.”  
                    In his testimony, Dr. Hansen said, he will 
                      say that the next president faces a unique opportunity to 
                      galvanize the country around the need for a transformed, 
                      nonpolluting energy system. The hearing is before the House 
                      Select Committee on Energy Independence and Global Warming. 
                     
                    Dr. Hansen said the natural skepticism and 
                      debates embedded in the scientific process had distracted 
                      the public from the confidence experts have in a future 
                      with centuries of changing climate patterns and higher sea 
                      levels under rising carbon dioxide concentrations. The confusion 
                      has been amplified by industries that extract or rely on 
                      fossil fuels, he said, and this has given cover to politicians 
                      who rely on contributions from such industries.  
                    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.  
                    The transformation would require new technology 
                      as well as new policies, particularly legislation promoting 
                      investments and practices that steadily reduce emissions. 
                     
                    Such an enterprise would be on the scale of 
                      past ambitious national initiatives, Dr. Hansen said, like 
                      the construction of the federal highway system and the Apollo 
                      space program. 
                     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.  
                    As was the case in 1988, Dr. Hansen’s peers 
                      in climatology, while concerned about the risks posed by 
                      unabated emissions, have mixed views on the probity of a 
                      scientist’s advocating a menu of policy choices outside 
                      his field. 
                     Some also do not see such high risks of imminent 
                      climatic calamity, particularly disagreeing with Dr. Hansen’s 
                      projection that sea levels could rise a couple of yards 
                      or more in this century if emissions continue unabated. 
                     
                    Dr. Hansen is a favorite target of conservative 
                      commentators; on FoxNews.com, one called him “alarmist in 
                      chief.” But many climate experts say Dr. Hansen, despite 
                      some faults, has been an essential prodder of the public 
                      and scientific conscience.  
                    Jerry Mahlman, who recently retired from a 
                      long career in climatology, said he disagreed with some 
                      of Dr. Hansen’s characterizations of the climate problem 
                      and his ideas about solutions. “On the whole, though, he’s 
                      been helpful,” Dr. Mahlman said. “He pushes the edge, but 
                      most of the time it’s pedagogically sound.”  
                    Dr. Hansen said he was making a new public 
                      push now because the coming year presented a unique opportunity, 
                      with a new administration and the world waiting for the 
                      United States to re-engage in treaty talks scheduled to 
                      culminate with a new climate pact at the end of 2009. 
                     He said a recent focus on China, which has 
                      surpassed the United States in annual carbon dioxide emissions, 
                      obscured the fact that the United States, Britain and Germany 
                      are most responsible for the accumulation of greenhouse 
                      gases.  
                    Dr. Hansen said he had no regrets about stepping 
                      into the realm of policy, despite much criticism.  
                    “I only regret that we haven’t gotten the 
                      story across as well as it needs to be,” he said. “And I 
                      think we’re running out of time.” 
                          
                              
                             
                          
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