Almost 200 countries have reached an agreement to phase out a powerful greenhouse gas used in air conditioners, refrigerators and insulating foams.
On Oct. 15, the 197 parties that enforce the Montreal Protocol on Substances that Deplete the Ozone Layer, including the U.S., agreed to a landmark deal to reduce the emissions of hydrofluorocarbons (HFCs), in a move that scientists estimate could prevent up to 0.5 degrees Celsius of global warming by the end of the century.
The agreement to amend the treaty after seven years of negotiations was ratified during the annual meeting held in Kigali, Rwanda.
“It is not often you get a chance to have a 0.5-degree centigrade reduction by taking one single step together as countries—each doing different things perhaps at different times, but getting the job done,” U.S. Secretary of State John Kerry said in a statement. “If we continue to remember the high stakes for every country on Earth, the global transition to a clean energy economy is going to accelerate.”
Under the phase-out agreement, developed countries will begin to phase down HFCs by 2019 and developing countries will follow with a freeze of HFCs consumption levels in 2024, with some countries freezing consumption in 2028. Under the agreement all countries are expected to consume no more than 15-to-20 percent of their respective baselines by the late 2040’s.
UN Environment Chief Erik Solheim said the agreement is the single largest contribution the world has made towards keeping global temperature rise “well below” 2 degrees Celsius, a target that the same group agreed to at a 2015 climate conference in Paris.
“Last year in Paris, we promised to keep the world safe from the worst effects of climate change,” Solheim said. “Today, we are following through on that promise. This is about much more than the ozone layer and HFCs. It is a clear statement by all world leaders that the green transformation started in Paris is irreversible and unstoppable. It shows the best investments are those in clean, efficient technologies.”
While the phase out is set to begin in the next three years, research on alternatives that do not deplete the ozone layer and have a smaller impact on the climate, while being cost efficient and effective is currently being explored.
According to the United Nations Environment Programme, HFCs are currently the world’s fastest growing greenhouse gases, with their emissions increasing by up to 10 percent per year. They also trap thousands of times more heat in the Earth’s atmosphere than another greenhouse gas, carbon dioxide.
HFCs have grown rapidly in recent years largely due to the growing demand for cooling, particularly in developing countries in hotter climates with a fast-growing middle class.
“The faster we act, the lower the financial costs will be and the lighter the environmental burden on our children,” Rwanda President Paul Kagame said in a statement. “That begins with a clear signal that change is coming and it is coming soon.