The use of hydrofluorocarbons (HFCs) in consumer products could be cut dramatically around the world if a climate change agreement between governments in Vienna is reached.
The potent greenhouse gases, which are commonly used in aerosols, refrigerants and air conditioning, form part of ten days of talks on climate change.
An agreement on reducing the use of HFC’s would be the biggest single measure to limit global warming since governments adopted the Paris Agreement last December.
Almost 200 countries have convened in Vienna to lay the groundwork for the deal, deciding upon details and timetables for almost eliminating HFC use around the world. This will be the last time they meet prior to a final agreement which is expected to be reached at an event in October in Kigali, Rwanda.
Governments "succeeded in laying the ground work for adoption of an ambitious HFC amendment ... in Kigali," the US Environmental Protection Agency (EPA) said in a statement.
Under the current draft of the agreement, rich nations would get a target of almost eliminating HFCs by the 2030s, while poorer nations, which may struggle with the high costs of shifting to new technologies, would get a decade or so longer.
UK government advisers have already warned that it needs to take urgent action in order to prevent a massive increase in the risks of flooding and heatwaves caused by climate change.
"The odds are very high for a deal in Kigali," said David Doniger of the US Natural Resources Defense Council.
Developing nations would also get financial support from nations led by the US and the European Union. India was least ambitious among major nations, favouring a freeze on growth in HFCs only in 2031.
"This single step could avoid up to 0.5 degrees Celsius of warming by 2100," the EPA said of cutting use of HFCs.
Paris set a goal of phasing out greenhouse gas emissions by 2100, mainly by shifting away from fossil fuels, and a target of limiting a rise in average global surface temperatures to ‘well below’ 2C above pre-industrial times.
Temperatures this year are on track to be the warmest on record, eclipsing 2015, according to the World Meteorological Organization. Temperatures are already about 1°C above pre-industrial times.
The HFC talks are part of the 1987 Montreal Protocol, which succeeded in slashing the use of chlorofluorocarbons (CFCs) to help protect the ozone layer, which shields the planet from ultraviolet rays that can cause skin cancer.
But the HFCs that have often replaced them, while better for the ozone layer, are greenhouse gases thousands of times more potent than carbon dioxide.