If good news about the environment has seemed scant lately, well, that's because it is. After all, 15,000 scientists recently released a collective letter warning humanity that we are on the verge of being unable to prevent "catastrophic biodiversity loss," and that we need to make significant changes to preserve Earth. It turns out, though, that some changes already made are having significant effects on our environment: According to a NASA study published Jan. 4 in the journal Geophysical Research Letters, the ozone hole over the Antarctic is slowly healing, and it may very well be gone within our lifetime.
Both ozone depletion and climate change are caused by people releasing pollutants into our atmosphere, according to the Union of Concerned Scientists. And though it doesn't cause climate change, ozone depletion does have a massive effect on us, since the ozone is our natural protection against ultraviolet radiation from the sun. So, the less ozone we have, the more UV light we're exposed to, and the more danger we're in.
Previous information out of MIT suggested the hole in the ozone layer was shrinking and would close by 2050, but new info out of the Goddard Space Flight Center in Greenbelt, Maryland, estimates it will take a little bit longer to repair the damage done so the ozone can do its job. The ozone's healing is due to an international ban on chlorofluorocarbons (CFCs) signed in 1987. Chlorofluorocarbons are manmade chemicals, originally developed to replace toxic chemicals like ammonia and sulfur dioxide, which used to be used in refrigerators and air conditioning units.
In response to a 1976 announcement from the National Academies of Science that proved CFCs were damaging our stratospheric ozone, as well as the 1985 discovery of the Antarctica ozone hole, countries around the world signed the Montreal Protocol on Substances that Deplete the Ozone Layer. A write-up from NASA says that originally, the Montreal Protocol "regulated ozone-depleting compounds," but "[later] amendments to the Montreal Protocol completely phased out production of CFCs."
The study released Jan. 4 shows tangible evidence that the Montreal Protocol policies put in place to protect the ozone are working. Observation of the ozone hole — which forms over the Antarctic each September "as the returning sun's rays catalyze ozone destruction cycles involving chlorine and brome that come primarily from CFCs," according to NASA — has been done with NASA's Aura satellite since 2005. Aura takes measurements of chlorine and ozone, and its data has shown that the ban on CFCs has "resulted in about 20 percent less ozone depletion during the Antarctic winter than there was during 2005."
If you're wondering why we're just now seeing results from a ban signed 30 years ago, it's because CFCs have dramatically long lifetimes: 50 to 100 years, according to Goddard atmospheric scientist Anne Douglass. "[They] linger in the atmosphere for a very long time," she says in NASA's writeup.
That means that as for the ozone hole being gone, "we're looking at 2060 or 2080." And even then, she adds, "there might still be a small hole."
While that's fantastic news, the elimination of CFCs unfortunately has not been a catch-all solution. Many products that once contained CFCs — including, infamously, those beloved '80s aerosol hairsprays — now emit volatile organic compounds (VOCs), according to Scientific American. These compounds "contribute to ground-level ozone levels, a key component of asthma-inducing smog," wrote Scientific American's EarthTalk. California is already on top of targeting products that emit VOCs, including "fingernail polish, perfumes, mouthwashes, pump hair sprays, and roll-on and stick deodorants," but more policy needs to be changed in order for this change to be effective on the long run.
Considering the ozone's healing has been primarily thanks to sweeping international brands and moves from big corporations, it can be tough to know what you can do to help from a grassroots position. As is usual, having a good knowledge base is the best starting point. You can also campaign to lower other types of harmful emissions, including VOCs and F-gases, by donating to research and contacting your local representatives.
It's a rare treat to hear positive news about Earth and humanity's impact on it. Be happy about it, share it, enjoy it — but remember this is one small buoy of good in a sea of bad.