It’s been almost forty years since scientists discovered the growing hole in Earth’s ozone layer.
But climate researchers now say the protective shield, about 20 miles (30 kilometers) above our planet’s surface, is well on its way to recovery.
New data collected by NASA shows that the ozone hole over Antarctica this year was the seventh smallest since 1992.
NASA and the National Oceanic and Atmospheric Administration (NOAA) predict that the layer could fully recover as early as 2066.
Dr. Paul Newman, leader of NASA’s ozone research team, said: ‘The Antarctic hole in 2024 will be smaller than the ozone holes we saw in the early 2000s.
“The gradual improvement we’ve seen over the past two decades shows that international efforts to curb ozone-destroying chemicals are working.”
However, the ozone hole still averaged almost 12 million square miles—three times the size of the contiguous United States.
Scientists warn that there is still a long way to go before the ozone layer returns to its natural thickness.
NASA has revealed that this year the hole in the ozone layer (pictured) has reached the seventh smallest size since 1992
As the ozone hole opens, higher levels of harmful UVB radiation can hit the Earth, increasing the risk of cancer and cataracts.
Every year, a combination of ozone-depleting chemicals and cold temperatures create an annual hole in the ozone layer over Antarctica.
Although this hole still rains harmful ultraviolet radiation on Antarctica every year, it has recently begun to show promising signs of recovery.
Using a combination of satellite observations and ground-launched weather balloons, NASA and NOAA measured the concentration of ozone gas in the atmosphere.
Their observations showed that the annual ozone layer over the South Pole was relatively small compared to other years during the peak depletion between September 7 and October 13.
At its largest size, the ozone hole covered an area of 22.4 million square kilometers on September 28 this year.
This is in stark contrast to 2023, when the ozone hole peaked at 26 million square kilometers on September 10.
While still significant, it is the twentieth smallest hole since records began in 1979 and the seventh smallest since ozone-depleting CFCs were banned under the Montreal Convention.
At its largest point this year, the hole in the ozone layer was 22.4 million square kilometers on September 28. This is 1.5 million square kilometers smaller than the peak size in 2023.
Scientists from NASA and the National Oceanic and Atmospheric Administration (NOAA) measured the ozone layer above Antarctica using satellites and weather balloons (photo). They now predict that the ozone layer will have fully recovered by 2066
CFCs (chlorofluorocarbons) are a type of man-made chemical that was widely used in aerosol cans and refrigeration.
Since the ban in 1992, the concentration of CFCs in the atmosphere has gradually decreased, allowing the ozone layer to recover.
A recent study by the Copernicus Atmosphere Monitoring Service (CAMS) found that the ozone hole took longer to form and was smaller than expected.
As of September 13, the ozone hole was 18.48 million square kilometers (7.13 million square miles), smaller than the same period in recent years.
Meanwhile, the ozone layer above the North Pole is also showing indications of a possible recovery.
This year, particularly favorable weather caused the Arctic ozone layer to become 14.5 percent thicker than the post-1980 average.
According to NASA and NOAA predictions, this means that the ozone layer could return to its pre-hole thickness in just over 40 years.
The scientists believe that the recent recovery is due to a combination of the natural decline of CFCs coupled with an influx of ozone from areas north of the Arctic.
In September this year, the hole in the ozone layer (shown in blue) was 7.13 million square kilometers – smaller than in the same period in recent years. Researchers suggest this is a sign that banning CFCs will naturally restore the ozone layer
The ozone layer still has a long way to go before it is restored. On October 5 this year (photo), the layer reached a thickness of just 109 Dobsonian units, less than half the pre-1979 average
Ozone built up in the stratosphere normally absorbs almost all radiation coming from the sun, protecting life on Earth from harmful radiation
During the winter months, swirling winds called the Polar Vortex typically concentrate ozone-depleting chemicals in a small area above the South Pole.
When the sun’s energy begins to hit the atmosphere in the spring, the combination of cold temperatures and solar radiation begins to erode the ozone layer.
However, in June, Antarctica experienced two rare ‘sudden stratospheric warming events’, causing temperatures in the upper atmosphere to rise by 15ºC (27ºF) and 17ºC (30.6ºF) respectively.
These peaks weakened the Polar Vortex significantly, slowing its depletion rate and allowing more ozone to reach the region above the pole.
However, NASA also warns that the ozone layer still has a long road to recovery.
Stephen Montzka, senior scientist at the NOAA Global Monitoring Laboratory, said: ‘For 2024, we could see the severity of the ozone hole being below average compared to other years in the last thirty years, but the ozone layer is still far from being completely healed. ‘
Scientists measure the thickness of the ozone layer using a measurement called Dobson units, where anything less than 220 Dobson units (DU) is considered an ozone hole.
At its thinnest point this year, on October 5, the atmosphere above Antarctica was only 109 DU.
Recent studies have shown that the ozone layer is making promising progress towards recovery. This graph shows that the Antarctic ozone hole formed later and was smaller than expected this year
Researchers have found that the ozone layer over the Arctic reached a record thickness in March 2024 (right). This is in stark contrast to March 2020 (left) when a record-breaking ozone hole formed over the Arctic
That’s slightly thicker than the lowest level ever recorded when the ozone layer hit 92 DU in 2006, but still thin enough to cause serious health risks.
In fact, a recent study found that Antarctic wildlife, such as seals and penguins, are at greater risk of sunburn due to ozone depletion.
According to Bryan Johnson, NOAA research chemist, 225 Dobson units were typical for the ozone layer over Antarctica in 1979.
“So there is still a long way to go before atmospheric ozone returns to the levels it was before the advent of widespread CFC pollution,” he said.