Hydrofluorocarbon

In 2016, more than 170 countries agreed to phase out hydrofluorocarbons, super polluting chemicals widely used in air conditioners and refrigerators.

Known as HFCs, they are an extremely potent greenhouse gas and trap much more heat than carbon dioxide.

Ten years later, it's clear that the agreement is succeeding and it offers a template for how other climate regulations might work despite political backlash to green policymaking, experts say.

The HFC deal has worked perfectly, said Paul Bledsoe, who worked on climate issues under President Bill Clinton and helped push for the HFC pact known as the Kajali Amendment.

It reduces temperatures fast and at an incredibly low cost.

Countries are ahead of their target to cut production and use of HFCs.

Chemical companies support the deal and are rolling out alternatives.

The United Nations says the accord is projected to prevent 0.5 degrees Celsius of warming or 0.9 degrees Fahrenheit by the end of the century.

CO2 rack connects to a store's existing HFC refrigeration system, according to Letnan.

He explained that the design reduces the amount of HFCs in the store and the potential for leaks by replacing HFC refrigerants on the retail floor with liquid CO2.

And there is increasing realization that to focus narrowly on carbon dioxide is a fool's errand.

There has been, over the past several years, increasing focus on HFCs, hydrofluorocarbons, in large part thanks to EIA's work on the topic, but also methane and black carbon and ground-level ozone.

and now nitrous oxide as well.

And the thing that also about nitrous oxide that makes it very important that we deal with it as a climate issue is it's really unique chemistry, which we call the nitrogen cascade, which is this idea that once nitrogen is out of the atmosphere as N2, It can go on a journey of environmental distraction where it makes a whole slew of environmental and human health problems worse.

And we've got abatement technologies, and we have had for two decades at this point, that can abate those emissions very effectively and very cost-effectively.

When it comes to byproduct emissions, we actually do have this really good precedent under the protocol.

So 10 years ago this year, the Kigali Amendment to the Montreal Protocol was signed, and that brought HFCs, hydrofluorocarbons, under the treaty.

As part of that, they introduced a byproduct destruction requirement for a specific HFC called HFC23, a really potent greenhouse gas.

So I got involved with a, a climate advocacy group, um, so 350 Silicon Valley at the time, now Climate Action California, um, doing a lot of climate policy work.

Initially, I was looking at plastics, but then I got really interested in short-lived climate pollutants, so methane, um, HFCs, black carbon, that sort of thing, because that seemed...

And I think one thing that I started to realize was, you know, I initially I was thinking about plastics, but I was thinking, "What do I really care about here? I care about the climate, and I care about doing the most effective thing I can to stop climate change.

What are the real, um, crux points when it comes to helping climate change? How have we made progress, and where are the opportunities to make progress further?" So with that in mind, you know, started focusing on those short-lived pollutants, explored a bunch of different projects in freshman year, um, got involved with the geothermal, uh, club that I talked about earlier, and I think, you know, it just, everything started to come down to we care about why things cost the way they do.

Far more efficient and less toxic than earlier refrigerants, CFCs, like Freon, allowed home refrigerators to be made far safer and more compact than earlier models, causing prices to halve and ownership to double by the end of the decade.

Of course, in the 1970s, it was discovered that CFCs deplete the Earth's UV-absorbing ozone layer, leading them to be banned by the 1987 Montreal Protocol and replaced by less damaging alternatives like hydrochlorofluorocarbons, or HFCs, hydrofluoroolefins, or HFOs, and even flammable gases like isobutane and propane.

As an aside, Midgley also discovered the anti-knock agent tetraethyllead, widely added to gasoline throughout the 20th century and responsible for even more global environmental damage, making Midgley perhaps the inventor whose work has killed more humans unintentionally than any other inventor in history.

Sadly, or absurdly funny depending on how you look at it, it was his final invention that was the deadliest, from his perspective anyway.

This amendment follows the 1987 Montreal Protocol, a climate treaty that phased out 100 types of ozone-depleting chemicals known as chlorofluorocarbons, or CFCs, which started destroying Earth's ozone layer.

The problem was manufacturers replaced CFCs with hydrofluorocarbons, or HFCs, which aren't great either.

While the ozone hole did get smaller, HFCs have a far worse greenhouse effect than CO2.

Whereas carbon dioxide has a warming potential of 1 based on its ability to trap heat and methane has a warming potential of 34, HFCs have warming potentials ranging from 1,370 to 4,180, which makes them way worse for climate change.

So the Kigali Amendment expands on those original ozone depleters to phase out 100% of HFCs, which means manufacturers in the US and most of the rest of the world won't be able to use these compounds at all by 2050.

While HFCs are out as of this year, comeback stories are in.

In an age of massive biodiversity loss, it turns out that some animal species are making dramatic recoveries.

Across Europe, over 50 species are returning in record numbers after reintroduction to expanded habitats across the continent.