Chilling Effect: In Rising Use of Air-Conditioning, Hard Choices

Kuni Takahashi for The New York Times

Growing demand for air-conditioning in developing nations, as here in Mumbai, India, has raised concerns about global warming.

In the ramshackle apartment blocks and sooty cement homes that line the dusty roads of urban India, there is a new status symbol on proud display. An air-conditioner has become a sign of middle-class status in developing nations, a must-have dowry item.

It is cheaper than a car, and arguably more life-changing in steamy regions, where cooling can make it easier for a child to study or a worker to sleep.

But as air-conditioners sprout from windows and storefronts across the world, scientists are becoming increasingly alarmed about the impact of the gases on which they run. All are potent agents of global warming.

Air-conditioning sales are growing 20 percent a year in China and India, as middle classes grow, units become more affordable and temperatures rise with climate change. The potential cooling demands of upwardly mobile Mumbai, India, alone have been estimated to be a quarter of those of the United States.

Air-conditioning gases are regulated primarily though a 1987 treaty called the Montreal Protocol, created to protect the ozone layer. It has reduced damage to that vital shield, which blocks cancer-causing ultraviolet rays, by mandating the use of progressively more benign gases. The oldest CFC coolants, which are highly damaging to the ozone layer, have been largely eliminated from use; and the newest ones, used widely in industrialized nations, have little or no effect on it.

But these gases have an impact the ozone treaty largely ignores. Pound for pound, they contribute to global warming thousands of times more than does CO2, the standard greenhouse gas.

Indeed, the leading scientists in the field have just calculated that if all the equipment entering the world market uses the newest gases currently employed in air-conditioners, up to 27 percent of all global warming will be attributable to those gases by 2050.

So the therapy to cure one global environmental disaster is now seeding another.?There is precious little time to do something, to act,? said Stephen O. Andersen, the co-chairman of the treaty?s technical and economic advisory panel.

The numbers are all moving in the wrong direction.

Atmospheric concentrations of the gases that replaced CFCs, known as HCFCs, which are mildly damaging to the ozone, are still rising rapidly at a time when many scientists anticipated they should have been falling as the treaty is phasing them out. The levels of these gases, the mainstay of booming air-conditioning sectors in the developing world, have more than doubled in the past two decades to record highs, according to the National Oceanic and Atmospheric Administration.

And concentrations of the newer, ozone-friendly gases are also rising meteorically, because industrialized countries began switching to them a decade ago. New room air-conditioners in the United States now use an HFC coolant called 410a, labeled ?environmentally friendly? because it spares the ozone. But its warming effect is 2,100 times that of CO2. And the treaty cannot control the rise of these coolants because it regulates only ozone-depleting gases.

The treaty timetable requires dozens of developing countries, including China and India, to also begin switching next year from HCFCs to gases with less impact on the ozone. But the United States and other wealthy nations are prodding them to choose ones that do not warm the planet. This week in Rio de Janeiro, Secretary of State Hillary Rodham Clinton is attending the United Nations Conference on Sustainable Development, also known as Rio+20, where proposals to gradually eliminate HFCs for their warming effect are on the provisional agenda.

But she faces resistance, because the United States is essentially telling the other nations to do what it has not: to leapfrog this generation of coolants. The trouble is, there are currently no readily available commercial ozone-friendly alternatives for air-conditioners that do not also have a strong warming effect ? though there are many on the horizon.

Nearly all chemical and air-conditioning companies ? including DuPont, the American chemical giant, and Daiken, one of Japan?s leading appliance manufacturers ? have developed air-conditioning appliances and gases that do not contribute to global warming. Companies have even erected factories to produce them.

But these products require regulatory approvals before they can be sold, and the development of new safety standards, because the gases in them are often flammable or toxic. And with profits booming from current cooling systems and no effective regulation of HFCs, there is little incentive for countries or companies to move the new designs to market.

?There are no good solutions right now ? that?s why countries are grappling, tapping in the dark,? said Rajendra Shende, the recently retired head of the Paris-based United Nations ozone program, who now runs the Terre Policy Center in Pune, India.

The 25-year-old Montreal Protocol is widely regarded as the most successful environmental treaty ever, essentially eliminating the use of CFC coolants, which are highly damaging to the ozone layer. Under its terms, wealthier countries shift away from each harmful gas first, and developing countries follow a decade or more later so that replacement technologies can be perfected and fall in price.

Source: http://feeds.nytimes.com/click.phdo?i=cf329bbccaf361881f059bf085d35132

list of world newspapers live world news with diane sawyer major world newspapers nbc world news today nbc world news tonight