The ozone layer is a lot like the Earth’s sunscreen, if it was applied extremely haphazardly and resulted in a sunburn. That’s not the fault of ozone — it’s ours. The toxic gas layer is supposed to shield the planet from ultraviolet radiation, which can cause skin cancer, suppress immune systems, and damage plants. But as we all know, the ozone layer is damaged, and its hole is larger in 2018 than it has been before.

But according to a video released Friday by NASA, the current status of the hole would be much worse if not for the Montreal Protocol of 1987. Currently, the ozone hole in the upper atmosphere over Antartica is bigger than it has been on average over the years and is larger than it was in 2016 and 2017. Its expansion isn’t caused so much by recent — emphasis on recent — human failures, say scientists, but by colder-than-average temperatures in the Antarctic stratosphere.

These temperatures “created ideal conditions for destroying ozone this year,” says NASA, but “declining levels of ozone-depleting chemicals prevented the hole from being as large as it would have been 20 years ago.”

ozone layer
The purple and blue colors are where there is the least ozone and the yellows and reds are where there is more ozone.

About 31 years ago, the world’s nations agreed to the Montreal Protocol, which bans the use of chemicals that destroy ozone such as chlorofluorocarbons and other halogenated ozone-depleting substances. These chemicals — used in processes like refrigeration, fire suppression, and foam insulation — are dangerous because the chlorine and bromine atoms in them destroy ozone molecules when they interact with them in the stratosphere.

The ban itself has been largely successful. The ozone layer has started to recover, and despite this year’s measurement, it has gotten slightly smaller each year. NASA scientists say that in spite of the colder temperatures that spurred hole growth, the current size of the ozone hole would be much larger if the Montreal Protocol had not been enacted. Currently, the hole covers an average area of 8.83 million square miles, almost three times the size of the United States.

Additionally, a new report released by the United Nations’ Global Ozone Research and Monitoring Project states that if nations continue to adhere to the Montreal Protocol, the Antarctic ozone hole could be healed by the 2060s.

“As a result of the Montreal Protocol, much more severe ozone depletion in the polar regions has been avoided,” the report states. “Outside the polar regions, upper stratospheric ozone has increased by 1 to 3 percent per decade since 2000.”

Photos via NASA (1, 2)