US Secretary of State John Kerry gestures as he delivers a speech during the 28th Meeting of the Parties to the Montreal Protocol in Kigali, on October 14, 2016.

Nearly 200 nations have reached a deal to limit the use of greenhouse gases far more powerful than carbon dioxide in a major effort to fight climate change.

The talks on hydrofluorocarbons, or HFCs, were called the first test of global will since the historic Paris Agreement to cut carbon emissions was reached last year. HFCs are described as the world’s fastest-growing climate pollutant and are used in air conditioners and refrigerators.

The agreement, announced Saturday morning after all-night negotiations, caps and reduces the use of HFCs in a gradual process beginning by 2019 with action by developed countries including the United States, the world’s second-worst polluter. More than 100 developing countries, including China, the world’s top carbon emitter, will start taking action by 2024, when HFC consumption levels should peak.

A small group of countries including India, Pakistan and some Gulf states pushed for and secured a later start in 2028, saying their economies need more time to grow. That’s three years earlier than India, the world’s third-worst polluter, had first proposed.

Historic moment

“It’s a very historic moment, and we are all very delighted that we have come to this point where we can reach a consensus and agree to most of the issues that were on the table,” said India’s chief delegate, Ajay Narayan Jha.

Environmental groups had hoped that the deal could reduce global warming by a half-degree Celsius by the end of this century. This agreement gets about 90 percent of the way there, said Durwood Zaelke, president of the Institute for Governance and Sustainable Development.

Zaelke’s group said this is the “largest temperature reduction ever achieved by a single agreement.”

Experts said they hope that market forces will help speed up the limits agreed to in the deal.

HFCs were introduced in the 1980s as a substitute for ozone-depleting gases. But their danger has grown as air conditioner and refrigerator sales have soared in emerging economies like China and India. HFCs are also found in inhalers and insulating foams.

The UN says the next meeting in 2017 will determine how much of the billions of dollars needed to finance the reduction of HFCs will be provided by countries.

[vuukle]