Act on Climate Change, Top Scientists Warn Us

A group of 1,700 leading scientists called on the US government yesterday to take the lead in fighting global warming. Citing the "unprecedented and unanticipated" effects of global warming, the scientists, including six Nobel prizewinners, presented a letter calling for an immediate reduction in US carbon emissions.

The statement came as the Senate prepares to debate a bill next week that would impose economy-wide limits on greenhouse emissions to avert what it describes as "catastrophic climate change".

The letter, issued by the non-profit Union of Concerned Scientists, warns: "If emissions continue unabated, our nation and the world will face more sea level rise, heat waves, droughts, wildfires, snow melt, flood risk, and public health threats, as well as increased rates of plant and animal species extinctions."

The White House joined in the chorus of gloom when it issued a long-delayed report bringing together research into global warming. The report was issued after environmental groups won a court order last year enforcing a statute that obliges the government to produce an assessment of global warming every four years. Described as "a litany of bad news in store for the US", the report catalogs threats from drought, natural disaster, insect infestation and energy shortages.

The scientists call on the government to "put our nation on to a path today to reduce emissions on the order of 80% below 2000 levels by 2050." As a first step, the scientists call for a 15-20% reduction on 2000 levels by 2020. "There is no time to waste," the letter concludes. "The most risky thing we can do is nothing."

The targets go beyond those proposed by senators Joe Lieberman and John Warner in America's climate security act, due to be debated on Monday. Citing the prospect of rises in diseases such as malaria and asthma from hotter temperatures, as well as hunger, dislocation and death due to storms, that bill calls for a cut of up to 63% on 2005 levels by 2050.

Another group of climate scientists warned yesterday that a "false optimism" has infused international climate talks, saying that politicians should deliver "stringent emissions cuts and major adaptation efforts" or risk profound consequences for the planet.

The scientists said the world has lost 10 years talking about climate change when it should have acted. "A curious optimism ... pervades the political arenas of the G8 and UN climate meetings. This is false optimism and is obscuring reality," they write in Nature Reports Climate Change. The authors are part of the Intergovernmental Panel on Climate Change, but stress in this paper they do not represent the panel.

The scientists say that even the most politically feasible target, of a 50% global reduction in greenhouse gases by 2050 from the levels of 1990, would still entail "major global impacts". They used new modeling data on the impact of differing long-term cuts in greenhouse gas emissions. "For the first time we can read off what damages are avoided or not avoided for different amounts of emissions cuts," said Professor Martin Parry.