WMO has welcomed the deal by nearly 200 countries to reduce emissions of powerful greenhouse gases, hydrofluorocarbons (HFCs), in a move which could prevent up to 0.5 degrees Celsius of additional global warming by the end of this century.
Meeting in Kigali, Rwanda, governments agreed to an amendment to the Montreal Protocol on Substances that Deplete the Ozone Layer. Under this, developed countries will start to phase down HFCs by 2019. Developing countries will freeze HFC consumption levels in starting in 2024. There will be adequate financing for HFC reduction.
A joint assessment report by the UN Environment Programme and World Meteorological Organization in 2014 said that although HFCs did not damage the ozone layer, they were very powerful greenhouse gases. With emissions growing more than 7% per year, if left unabated, HFCs could potentially contribute very significantly to global warming in the coming decades, the joint assessment warned.
“The Kigali Amendment is good news for the climate and reinforces the role of the Montreal Protocol both in protecting the ozone layer and limiting climate change,” said Geir Braathen, a senior atmospheric scientist at WMO. “It is considered absolutely vital for reaching the Paris Agreement target of keeping global temperature rise to below 2° Celsius compared to pre-industrial times,” he said.
Commonly used in refrigeration and air conditioning, HFCs were developed as an alternative to ozone destroying chlorofluorocarbons, or CFCs, which have been eliminated under the Montreal Protocol.
Thanks to action under the Montreal Protocol, Earth’s protective ozone layer is well on track to recovery in the next few decades. It is expected to recover to 1980 benchmark levels before the middle of the century in mid-latitudes and somewhat later in the Antarctic.
WMO monitors the annual ozone hole over the Antarctic. This year the maximum size of the hole was on 28 September with 23.1 million km2, lower than the 28.2 million km2 observed in 2015 but similar to other recent years, according to the WMO Antarctic Ozone Bulletin. Colder than usual high-altitude (stratospheric) temperature conditions in the Antarctic contributed to the large ozone hole in 2015, and highlighted the need for the international community to remain vigilant. But the overall trend is towards long-term recovery of the ozone layer.
The Kigali Amendment comes just weeks ahead of the U.N. climate change negotiations in Marrakech, Morocco, where the international community will work to strengthen the global response to the threat of climate change, with the central focus placed on promoting implementation of the Paris Climate Change Agreement.
UNEP Montreal Protocol press release here