The Ozone Layer's Recovery Underscores What Scientists Have Been Saying All Along

“It’s nice to have some positive environmental news for a change.”

At its current rate of recovery, the hole in our planet's ozone layer won't be closed until the 2060s or even the 2080s, according to Susan Strahan of NASA's Goddard Spaceflight Center. But it is closing, meaning we humans are capable of making progress to reversing the damage we've done —just as climate scientists have said.


The ozone layer protects Earth from ultraviolet radiation, and scientists discovered the gaping hole in the ozone in the 1980s and blamed chlorofluorocarbons (CFCs) used at the time in products like aerosol sprays and refrigerants, as Newsweek reports. In 1987, 197 nations signed the Montreal Protocol and agreed to phase out ozone-destroying chemicals. Only now, however, are we really understanding how well that protocol worked.

In a study published this week in Geophysical Research Letters, Strahan and her colleague Anne Douglass used data collected by NASA's Aura satellite to examine changing ozone levels about Antartica from 2005 to 2016. They found ozone depletion had declined by around 20 percent and chlorine levels had declined at a rate of around 0.8 percent per year, the latter statistic aligning with Montreal Protocol projections. In fact, as NASA and NOAA announced in November, the ozone hole was smaller in 2017 than it's ever been since 1988.

"We see very clearly that chlorine from [chlorofluorocarbons] is going down in the ozone hole, and that less ozone depletion is occurring because of it," Strahan said in a statement.

Scientist Bill Randall of the University Corporation for Atmospheric Research tells Earther the analysis is "very well done." 

"They're seeing net decreases in chlorine that are very consistent with the Montreal Protocol," Randall said. "That's a big take-home message: that the Montreal Protocol is doing what we think it should be doing."

And, he added, "it's nice to have some positive environmental news for a change."

The ozone recovery was even cited as an example of successful environmental intervention in an open letter signed by more than 15,000 scientists and published this November in BioScience

"The rapid global decline in ozone-depleting substances shows that we can make positive change when we act decisively," they wrote. "Soon it will be too late to shift course away from our failing trajectory, and time is running out. We must recognize, in our day-to-day lives and in our governing institutions, that Earth with all its life is our only home."

For more information on ozone preservation, the Montreal Protocol, and the #OzoneHeroes social media campaign, visit the United Nations' website.

Cover image via Shutterstock / studio23


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