CLIMATE CHANGING?: Traffic moves at half a mile an hour on Sukhumvit Road in Bangkok, Thailand. Such vehicles contribute roughly one-quarter of man-made greenhouse gas emissions. Image: © PAUL SOUDERS/CORBIS
Bangkok, Thailand, represents one future for global transportation. Short trips last hours, whether by bus or car, and by evening traffic can average half a mile an hour in some spots, far slower than walking speed. Bangkok's nine million or so denizens support two million personal vehicles. "Unfortunately, the personal vehicle has become sort of synonymous with being a rich, civilized person," notes Steven Plotkin, a transportation energy analyst at Argonne National Laboratory in Illinois. "It's one of the first things you buy when you get some money together."
Worldwide, the desire for automobiles and the traffic it inspires burns fuel at an alarming pace, contributing to an ever increasing amount of greenhouse gases, particularly carbon dioxide. As the new report from the Intergovernmental Panel on Climate Change (IPCC) released today in Bangkok reveals, cutting back on those emissions is a critical task.
Worldwide emissions of all greenhouse gases have nearly doubled since 1970 thanks to a rise in the worldwide use of energy, whether fuel in cars or electricity from a coal-fired power plant. In that time emissions of carbon dioxide (CO2) alone rose by "about 80 percent," according to the report, with 28 percent of that increase occurring since 1990 alone. Nothing in sight will check this rise: cars are only getting more popular and more of the world is consuming coal-fired electricity. China alone added 90 gigawatts of coal-fired power plants in 2006, roughly equivalent to the total power production of Germany, according to Richard Bradley, head of the energy efficiency and environment division at the International Energy Agency (IEA) in Paris.
If CO2 levels in the atmosphere—currently 379 parts per million (ppm)—reach roughly 550 ppm, scientists estimate temperatures would rise by three degrees Celsius (5.4 degrees Fahrenheit) on average. Such a rise would have a host of impacts, ranging from shrinking glaciers (and imperiled supplies of fresh water) to extreme weather events and natural disasters such as forest fires and pest outbreaks, according to the IPCC.
Fortunately, a range of options exist to attempt to mitigate the amount of CO2 and other greenhouse gases emitted into the atmosphere. First and foremost is simply using energy wisely—so-called energy efficiency. "The most benefit with the least cost would come from energy efficiency," argues Harlan Watson, the senior climate negotiator for the U.S. "If we are going to address climate change in the long run we have to reduce and indeed reverse the growth in global emissions. The best way to do that is to employ a portfolio across many sectors."
For example, the report calls for more efficient buildings. "For new buildings, this runs the gamut from proper insulation; good windows; energy-efficient heating, cooling and ventilation; efficient appliances and plug loads that have much-reduced standby losses," says Mark Levine, a senior staff scientist at Lawrence Berkeley National Laboratory in California. "It will be possible as time goes on to construct commercial buildings that are much more energy efficient than at present." And it doesn't have to cost more. The report notes that "by 2030, about 30 percent of the projected [greenhouse gas] emissions in the building sector can be avoided with net economic benefit."
From increasing the use of low-carbon sources of energy such as nuclear and solar power to reducing the nearly 13 megahectares (about 50,200 square miles, or roughly the size of New York State) of forest cleared every year (which contributes roughly 5.8 gigatonnes of CO2 to the atmosphere annually), the report lays out ways the world can reduce emissions. Even transportation can be improved. "You can double the efficiency of the U.S. fleet [of vehicles] with technology that is in existence today," Argonne's Plotkin says. "It just takes the will."