WASHINGTON -- When negotiators from nearly 200 countries gathered outside Paris in December for the United Nations summit meeting on climate change, they reached the first agreement to take action on curbing their planet-warming pollution.
This weekend in Vienna, with far less attention, negotiators from those same countries are nearing a deal that many environmentalists have called the most significant action this year to reduce global warming.
While the Paris agreement aims to reduce the use of coal and oil, which produce the carbon dioxide emissions that are the chief cause of global warming, negotiators in Vienna are working on a deal to ban the use of hydrofluorocarbons, chemicals used in air conditioners and refrigerators. Although they contribute only a small percentage of the world's greenhouse gases, these chemicals can trap heat in the atmosphere at levels a thousand times higher than carbon dioxide can, according to published scientific studies.
Negotiations to ban hydrofluorocarbons have dragged on for seven years. But if agreement is reached in Vienna, a final deal could be signed during an October conference in Kigali, Rwanda.
The deal would be an amendment to the Montreal Protocol, the landmark 1989 environmental treaty designed to close the hole in the ozone layer by banning ozone-depleting coolants called chlorofluorocarbons.
In response, chemical companies developed hydrofluorocarbons, which do not harm the ozone. But the substitute had the wholly unexpected side effect of increasing heat trapped in the atmosphere, which worsened climate change.
The Montreal treaty allows nations to amend it to ban substitute chemicals that have negative environmental effects even if they do not harm the ozone. And U.S. chemical companies such as Dow, DuPont and Honeywell have already begun to patent climate-friendly hydrofluorocarbon substitutes.
Scientists estimate that an increase in average global temperatures of 3 degrees Fahrenheit could tip the planet into a dangerous future of rising sea levels, devastating droughts, extreme storms and shortages of food and water. Studies show that banning hydrofluorocarbons worldwide could prevent an increase of nearly one degree over the next century.
"This is such a big deal," said Andrew Light, a former State Department diplomat who played a key role in negotiating the Paris agreement and who now works for the World Resources Institute, a research organization. "This is the single biggest thing that could be done to reduce emissions from any one agreement."
Most countries support some form of a deal to phase out hydrofluorocarbons, but certain ones with developing economies, led by India, are pushing for a slow timeline. While the United States wants a deal that would phase out the chemicals within 10 years, Indian diplomats are pushing for 15 to 20. They say the costs of new substitute coolants will disproportionately affect the residents of developing countries in warm climates, where the use of air conditioning is expected to soar in coming decades.
"An earlier date would impose economywide costs on India," said Arunabha Ghosh, chief executive officer of the Council on Energy, Environment and Water in New Delhi. "The cost of alternative refrigerants are eight to 10 times what is available."
President Barack Obama, who has sought to make climate change prevention a cornerstone of his legacy, has spoken at length with Prime Minister Narendra Modi of India about reaching a deal, and Secretary of State John Kerry flew to Vienna on Friday to personally engage in the negotiations. He pledged that a final deal would include assistance from rich countries to help poorer ones deal with the cost of transitioning to the new chemicals, although he did not specify a dollar amount.
Final details of timing and financial aid are expected to be established at the October meeting in Kigali.
Many large U.S. chemical companies are pushing hard for the amendment. Final passage of the deal could create a new market for their coolants in refrigerators and air-conditioners around the world.
"Our member companies pushed for this amendment for years," said Francis Dietz, a vice president of the Air-Conditioning, Heating and Refrigeration Institute, a lobbying group. "It's sort of unusual for industry to spend a lot of time trying to get regulated. But we knew regulations of [hydrofluorocarbons] were coming down the pike, and we're ready."
The deal's support from major businesses has blunted much of the criticism that many Republicans in the United States typically pose at debates about efforts to control global warming. Obama administration officials have pointed out that the Montreal Protocol itself, which was largely negotiated by President Ronald Reagan, has long enjoyed bipartisan support. Those circumstances, and the relatively low profile of the Vienna talks, appear to have kept the hydrofluorocarbon amendment out of the political fray that often surrounds climate change policy.
Gina McCarthy, the Environmental Protection Agency administrator, who has led the U.S. delegation in Vienna, noted the change.
"It's very different from the Paris climate meetings," she said. "It's not been the same political dynamics as in that world."
A Section on 07/24/2016