Scientists Urge Energy Changes to Slow Warming
By Andrew C. Revkin (The New York Times) - May 3, 2007
The world’s established and emerging powers will need to divert substantially from today’s main energy sources within a few decades to limit centuries of rising temperatures and seas driven by the buildup of heat-trapping emissions in the air, the top body studying climate change is poised to conclude.
In an all-night session capping four days of talks, economists, scientists, and government officials from more than 100 countries agreed in Bangkok early on Friday local time on most sections of a report outlining ways to limit such emissions, led by carbon dioxide, an unavoidable byproduct of burning coal and oil.
The near-final report, from the Intergovernmental Panel on Climate Change, said prompt slowing of emissions could set the stage later in the century for stabilization of the concentration of carbon dioxide, which, at 380 parts per million now, has risen more than a third since the start of the industrial revolution and could easily double from the pre-industrial level within decades.
Dennis Tirpak, a lead author and former director of the Environmental Protection Agency’s climate division, declined to discuss details while the report was still in flux, but said the main message was clear: greenhouse gas emissions have soared since 1970 and could nearly double by 2030 if nothing is done.
Carbon dioxide is particularly important not only because so much is produced each year – about 25 billion tons – but because much of it persists in the atmosphere, building like unpaid credit card debt.
To stop the rise, the report’s authors said, countries would need to expand adoption of existing policies that can cut emissions – like a fuel tax or the binding limits set by the Kyoto Protocol – while also boosting research seeking new large-scale energy options. This work would include pushing for advances in solar and nuclear power.
According to several authors, the near-final report estimates that to bring global carbon dioxide emissions by 2030 to levels measured in 2000 would require a cost on released carbon dioxide of $50 to $100 a ton, a cost roughly on a par – in terms of fossil fuel prices – of an additional 25 to 50 cents for a gallon of gasoline.
The report projects that this shift might cause a small blunting of global economic activity, resulting in an overall reduction of perhaps one tenth of a percentage point per year through 2100 in the world’s total economic activity, authors said.
Some of the experts and government officials involved in the final discussions said in interviews and email messages that the costs could be substantially greater than that, adding that the report used very rosy assumptions.
But a variety of participants, including some from the United States government, said in interviews that it was hard to argue against such an investment given the potential costs of inaction.
This is the third report this year from the climate panel, which was formed under the auspices of the United Nations in 1988 to brief nations periodically on risks from human and natural changes in climate and options for limiting dangers.
In February, one team of experts concluded with near certainty that most warming since 1950 has been driven by the rising concentrations in the atmosphere of carbon dioxide and other greenhouse gases.
A second working group reported last month that the warming trend was already measurably shifting weather, water and ecological patterns, and that hundreds of millions of people faced risks by mid-century ranging from lost water supplies to inundated coasts should trends persist.
The latest report focuses on strategies and costs for cutting emissions of the warming gases.
William Moomaw, a lead author of a chapter on energy options and professor of international environmental policy at Tufts University, said he sees evidence, both in the United States and overseas, that big cuts can happen.
As evidence, he pointed to expanding requirements by states that utilities derive growing amounts of power from wind or other renewable sources, rapid improvements in energy efficiency for new homes and large buildings, Europe’s recent commitment to cutting emissions beyond existing targets, and promising statements from China about policy shifts.
European officials have said the climate panel’s reports will be stressed when climate policy comes up at the next meeting of the Group of Eight industrialized powers, which takes place next month.
The panel’s report on emissions options is also expected to play a role in shaping the next round of talks seeking new binding emissions restrictions after those set under the Kyoto treaty end in 2012. Those talks are scheduled to take place in Bali in December.