Earth's ozone layer is finally healing, UN says
S E E D E D C O N T E N T
WASHINGTON — Earth’s protective ozone layer is finally healing from damage caused by aerosol sprays and coolants, a new United Nations report said.
The ozone layer had been thinning since the late 1970s. Scientist raised the alarm and ozone-depleting chemicals were phased out worldwide.
As a result, the upper ozone layer above the Northern Hemisphere should be completely repaired in the 2030s and the gaping Antarctic ozone hole should disappear in the 2060s, according to a scientific assessment released Monday at a conference in Quito, Ecuador. The Southern Hemisphere lags a bit and its ozone layer should be healed by mid-century.
“It’s really good news,” said report co-chairman Paul Newman, chief Earth scientist at NASA’s Goddard Space Flight Center. “If ozone-depleting substances had continued to increase, we would have seen huge effects. We stopped that.”
High in the atmosphere, ozone shields Earth from ultraviolet rays that cause skin cancer, crop damage and other problems. Use of man-made chemicals called chlorofluorocarbons (CFCs), which release chlorine and bromine, began eating away at the ozone. In 1987, countries around the world agreed in the Montreal Protocol to phase out CFCs and businesses came up with replacements for spray cans and other uses.
At its worst in the late 1990s, about 10 percent of the upper ozone layer was depleted, said Newman. Since 2000, it has increased by about 1 to 3 percent per decade, the report said.
This year, the ozone hole over the South Pole peaked at nearly 9.6 million square miles (24.8 million square kilometers). That’s about 16 percent smaller than the biggest hole recorded — 11.4 million square miles (29.6 million square kilometers) in 2006.
The hole reaches its peak in September and October and disappears by late December until the next Southern Hemisphere spring, Newman said.
The ozone layer starts at about 6 miles (10 kilometers) above Earth and stretches for nearly 25 miles (40 kilometers); ozone is a colorless combination of three oxygen atoms.
If nothing had been done to stop the thinning, the world would have destroyed two-thirds of its ozone layer by 2065, Newman said.
But it’s not a complete success yet, said University of Colorado’s Brian Toon, who wasn’t part of the report.
“We are only at a point where recovery may have started,” Toon said, pointing to some ozone measurements that haven’t increased yet.
Another problem is that new technology has found an increase in emissions of a banned CFC out of East Asia, the report noted.
On its own, the ozone hole has slightly shielded Antarctica from the much larger effects of global warming — it has heated up but not as much as it likely would without ozone depletion, said Ross Salawitch, a University of Maryland atmospheric scientist who co-authored the report.
So a healed ozone layer will worsen man-made climate change there a bit, Newman said.
Scientists don’t know how much a healed ozone hole will further warm Antarctica, but they do know the immediate effects of ozone depletion on the world and human health, so “it would be incredibly irresponsible not to do this,” Salawitch said.
And the replacements now being used to cool cars and refrigerators need to be replaced themselves with chemicals that don’t worsen global warming, Newman said. An amendment to the Montreal Protocol that goes into effect next year would cut use of some of those gases.
“I don’t think we can do a victory lap until 2060,” Newman said. “That will be for our grandchildren to do.”
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“It’s really good news."
Well, yeah, to put it mildly. The thinning of our ozone layer is one of the biggest reasons for the jump in skin cancer and failure of crops. Let's hope it continues.
Good news. About ten years ago I had to replace our old central air unit. It is the R410A instead of R-22.
Wait so everything the UN said a couple weeks ago about the world coming to and end by 2040 if HUGE changes aren't made in carbon emmissions is BS? Who knew?/S
So a phenomenon that man has been able to measure since around 1960, with only 10 years of study it was determined that "Whoa" it's man's fault and we need to do something about it now and now it is subsiding and "Whew" man can take credit for halting it. It states right in the article the hole is seasonal, it develops from the lack of sunlight and lower O2 levels during the winter over the poles, so why can it not also be cyclic? Ozone is the byproduct of the O2 absorbing the UV from the sun.
This just goes to show us all how enacting simple sensible changes like universally altering the aeresol propellants and refrigeration coolants we all use can make a big difference for our environment which can heal itself when given a chance. This data in no way delegitimizes climate science as some here falsely portend. Climate scientists identified a dangerous environmental problem and provided governments worldwide some ways to address that problem which were then enacted thus effecting a significant improvement to a dire evolving predicament. How about we give them a listen regarding climate change now? When our scientists talk we all should listen.
Bullshit !
A few decades of changing things didn't SUDDENLY heal the ozone layer, after 100's of years of so-called abuse !
The ozone hole has been there for decades now. Aerosol and chlorofluorocarbons contributed to it. Reducing or eliminating these emissions have allowed the ozone layer to reform. Of course, full restoration will probably take many more decades. There's nothing "sudden" about it.
Hurray! I can finally relax. (looks sideways at dark spot on arm)
Overpopulation is still the problem that multiplies all other problems