Canada and Mexico have joined the US in proposing to expand the scope of the Montreal Protocol on substances that deplete the ozone layer to fight climate change. The proposal will phase down hydrofluorocarbons (HFCs), which are a significant and rapidly growing contributor to climate change.
The US Environmental Protection Agency (EPA) led the analysis in the proposal, which demonstrates environmental benefits equal to removing greenhouse gas emissions from 59 million passenger cars each year through 2020, and 420 million cars each year through 2050.
During the phaseout of chlorofluorocarbons (CFCs) under the Montreal Protocol and the Clean Air Act, manufacturers of equipment such as car air conditioners and kitchen refrigerators substituted HFCs. The trilateral proposal would phase down HFCs, which are up to 14,000 times more damaging to the Earth’s climate system than carbon dioxide, EPA said.
According to EPA, without this proposal, HFC use in developing countries is anticipated to grow substantially, driven both by increased demand for refrigeration and air-conditioning and because HFCs were developed as alternatives to ozone depleting substances.
Signed in 1987, the Montreal Protocol is a treaty with 196 countries to help restore the ozone layer by ending the production of ozone-depleting substances and now potentially phasing down HFCs.
EPA evaluates substitute chemicals and technologies for ozone-depleting substances. Additionally, EPA will propose four refrigerants as possible substitutes in US household and commercial refrigerators and freezers.
These hydrocarbon-based coolants will replace existing refrigerants that harm the stratospheric ozone layer and the climate system. The proposal lists isobutane, propane, HCR-188C, and HCR-188C1 as potentially acceptable substitutes for the ozone-depleting chemicals CFC-12 and HCFC-22.