Dramatic worldwide climate changes can no longer be avoided, but there is still time to stave off the worst consequences of global warming, an international research team said Tuesday. The scientists from 11 countries urged sweeping conservation measures to hold the expected increase in temperatures to no more than an average of 3.6 degrees Fahrenheit — less than half the expected increase if emissions of greenhouse gas and soot continue unabated.

Based on two years of study, the scientists called for bold actions, including carbon taxes, a ban on conventional coal-fired power plants and an end to beachfront construction worldwide. The researchers were financed by the nonprofit United Nations Foundation and the 60,000-member research society Sigma Xi. "Unlike many reports from scientists, this report gives very clear recommendations for what the international community and nations themselves must do to mitigate and adapt to climate change," said biodiversity expert Peter Raven, director of the Missouri Botanical Garden, who helped prepare a Sigma Xi study.

With its emphasis on policy recommendations, the panel's effort marks a shift in the international politics of pollution and climate change, analysts said. Researchers are no longer debating whether human-induced global warming is genuine, but have begun the painstaking process of negotiating international agreement on what to do about it. Their effort comes on the heels of a landmark United Nations report last month that concluded rising temperatures would continue to increase even if greenhouse gas emissions could be held to current levels.

Global temperatures have increased about 1.4 degrees Fahrenheit over pre-industrial levels, the researchers said. To meet the scientists' goal, global CO2 emissions must level off by 2015 and drop by two-thirds of that level by 2100. They urged stricter fuel efficiency standards, as well as fuel taxes, registration fees and rebates that favor more efficient transportation, which today is responsible for 40% of the world's carbon emissions. A 20-fold improvement in car efficiency is well within existing technology, they said. Moving freight by rail instead of truck could also cut emissions substantially.

The researchers also recommended the expanded use of biofuels to reduce dependence on the oil that accounts for one-quarter of the world's CO2 emissions. They endorsed broader use of nuclear power, if it can be made safer. Energy research budgets worldwide ought to triple, they said. In addition, the scientists called for improved designs of energy-efficient appliances, office equipment and "greener" commercial and residential buildings. Taken together, the heating, cooling and lighting of buildings accounts for about 30% of the world's greenhouse gas emissions.

Most tellingly, the panel called for a ban on any new coal-fired power plants that cannot be equipped to capture and store the carbon dioxide they emit. All told, the U.S., China and India plan to build about 850 coal-fired plants over the next decade, which by environmentalists' calculations would pump as much as five times more carbon dioxide into the atmosphere than international control measures aim to eliminate. No matter what people do to reduce soot or curtail emissions of carbon dioxide and other greenhouse gases, the world will continue to warm somewhat, and people will have to adapt, the researchers said.

To minimize the hazards of rising sea levels and more powerful storms, the group called for a worldwide ban on beachfront construction near existing high-tide lines. To reduce the effects of climate-related disasters, such as floods or prolonged droughts, the panel urged better international emergency response measures, warning that there may be as many as 50 million environmental refugees by 2010.
(Por Robert Lee Hotz, Los Angeles Times, 02/03/2007)