* Any views expressed in this opinion piece are those of the author and not of Thomson Reuters Foundation.
In trying to stop the ozone hole, we've created a new climate threat. Can it be stopped?
One of the hardest fought and most significant outcomes from last year’s UN Paris climate change accord was the agreement to try and limit global warming to 1.5 degrees above pre industrial levels, rather than the previous target of 2 degrees.
But now that the dust has settled, how are countries to turn this hard-won prize into reality? Temperatures are still rising and it’s unclear if the global transition to a low carbon world is happening fast enough yet.
The good news is that there is a little-known meeting taking place this week in Vienna that may help to take a massive chunk of projected greenhouse gasses out of the atmosphere and buy the world enough time to meet our 1.5 degree target.
The meeting in question is of the signatories of the Montreal Protocol. A response to the worrying hole in the ozone layer caused by harmful CFCs and HCFCs used in fridges and air conditioning, the Montreal Protocol has long been hailed as the most successful environmental treaty ever. The recent news of the ozone hole’s closure brought a fresh round of praise.
But by wiping out the use of CFCs, the Montreal agreement inadvertently helped to birth a new greenhouse gas, one that is up to 4,000 times more potent than carbon dioxide and entirely man made: hydroflurocarbons, or HFCs. Although they didn’t punch a hole in the ozone layer, these replacement chemicals do have an acute warming effect and, worryingly, their use is growing at a rate of 10-15 percent a year worldwide.
If this is left to continue we can kiss goodbye to that Paris target of keeping temperatures to 1.5 degrees.
In Vienna this week an amendment is being proposed to the Montreal Protocol to phasedown HFCs production and use around the world and replace them with alternatives with low global warming potential.
Experts predict that that this could result in atmospheric mitigation equivalent to 100 gigatonnes of carbon dioxide (with an additional possible 100 gigatonnes from related improvements in efficiency) and reduce warming by half a degree by 2100. That rapid mitigation may help us to avoid dangerous tipping points and buy us enough time to get the rest of our greenhouse gas emitting economy in order.
Historically most HFCs have come from developed countries but as incomes rise and consumer patterns change in the developing world their increase in these countries is marked. Some individual developed countries are already implementing polices to reduce their HFC use but an international rule is now required.
There is political will to get this done, such as a statement from the US and China Presidential summit, the US-India declaration and the G7 and G20 Leaders summit, all committing the world to fast action to phase down HFCS. The Montreal Protocol’s excellent track record on similar pollutants offers the perfect vehicle for this.
For example one obstacle it has overcome is the thorny issue which plagued the build-up to the Paris negotiations for years, that of ‘common but differentiated responsibilities’, or how to ensure how the richer, historic polluting countries do more of the heavy lifting.
Within the Montreal Protocol, developing countries phase down their use of ozone depleting chemicals in return for incremental financial support from developed countries through the Multilateral Fund. Since its inception, the fund has approved more than $3.3 billion to support more than 6,800 projects and activities.
A similar approach for HFCs would go a long way to cutting their use. Hopefully this week in Vienna progress will be made on such an amendment so that it can be formally adopted at a gathering in October in Kigali, the capital of Rwanda.
If the Protocol’s HFC loophole can be closed, in the same way it closed the hole in the ozone layer, then the world may have bought itself enough to deliver on its Paris Agreement promises.
Mohamed Adow is senior climate advisor at Christian Aid.