The earth's ozone layer is on track to repair itself in four decades. Researchers have even found a significant thickening of the ozone layer compared to 2018 levels, according to a report released yesterday (Jan. 9) by the United Nations Environment Program (UNEP) and the World Meteorological Organization (WMO).
5, 2022. Earth's protective ozone layer is slowly but noticeably healing at a pace that would fully mend the hole over Antarctica in about 43 years, a new United Nations report says.
The global average amount of ozone 18 miles (30 kilometers) high in the atmosphere won't be back to 1980 pre-thinning levels until about 2040, the report said. And it won't be back to normal in the Arctic until 2045.
In the latest report on the progress of the Montreal Protocol, the U.N.-backed panel confirmed that nearly 99% of banned ozone-depleting substances have been phased out. If current policies stay in place, the ozone layer is expected to recover to 1980 values by 2040, the U.N. announced.
Human action to save the ozone layer has worked as hoped, and it may recover in just decades, the UN says. An international agreement in 1987 to stop using the harmful chemicals that were damaging the layer has been successful, the major assessment says.
The hole still exists but scientists project the ozone layer to return to a condition not seen since before 1980 by about 2050.
If we could patch the hole over Antarctica, the natural ozone-oxygen cycle might fall back into balance. But unfortunately, we can't make more ozone to patch the hole. It takes a lot of energy to make ozone molecules -- in the atmosphere, the intense energy of the sun drives most of the work.
In late September 2022, the Antarctic ozone hole reached its maximum area of 24.5 million km². Up until early November 2022, the Antarctic ozone hole has been similarly large and long-lasting to the ones recorded in 2021 and 2020.
The extra carbon would likely warm the world by anywhere from 0.5 to 1 C by the end of the century, most likely around 0.8 C, the scientists estimate. That's on top of a likely 1.7 C of extra warming just from the greenhouse effect of CFCs in the atmosphere.
We don't hear much about the hole in the ozone layer anymore. That's because we've all but fixed it, thanks to consumer choices and a massive international agreement called the Montreal Protocol.
But in terms of the primary goal — healing the ozone layer — the worldwide effort was a huge success. CFC consumption declined from over 800,000 metric tons in the 1980s to an estimated 156 metric tons in 2014. Experts estimate that by 2050, the ozone layer will be back to the state it was in 1980.
While scientists expect the ozone hole to recover over time, there are still many natural forces affecting its progress. For example, given the long lifespan of ozone-depleting chemicals in the atmosphere, it will take decades for the hole to return to pre-industrial levels.
Ozone recovery
According to the Panel's report, if current policies remain in place, the layer is expected to recover to 1980 values by 2040. Over the Antarctic, this recovery is expected by around 2066, and by 2045 over the Arctic.
The stratospheric ozone layer absorbs the biologically damaging wavelengths of ultraviolet (UV) rays but in the 1970s, Australia's ozone layer was severely thinned as a consequence of heavy use of ozone-depleting, substances such as chloroflurocarbons (CFCs) and hydro-chloroflurocarbons (HCFCs).
Based on scientific assessments, the ozone layer is expected to return to pre-1980 levels around the middle of the century. Healing is slow because of the long lifespan of ozone-depleting molecules. Some persist in the atmosphere for 50 to 150 years before decaying.
Is climate change getting better or worse? If greenhouse gas emissions are increasing — which they are, according to NPR — then technically, climate change is getting worse. But before you lose hope and fall victim to climate doom, it's important to remember that our situation is still very complex.
The Earth formed more than 4 billion years ago along with the other planets in our solar system. The early Earth had no ozone layer and was probably very hot. The early Earth also had no free oxygen. Without an oxygen atmosphere very few things could live on the early Earth.
The amount of ozone required to shield Earth from biologically lethal UV radiation, wavelengths from 200 to 300 nanometers (nm), is believed to have been in existence 600 million years ago. At this time, the oxygen level was approximately 10% of its present atmospheric concentration.
Over the past 4.5 billion years, the Sun has gotten hotter, but also less massive. The solar wind, as we measure it today, is roughly constant over time. There are the occasional flares and mass ejections, but they barely factor into the Sun's overall rate at which it loses mass.
The ozone layer over New Zealand is thinner.
Unfortunately, due to decades of man-made gas emissions, the ozone layer over New Zealand has continuously thinned. The ozone layer is like the Earth's personal sun protectant. The ozone layer's role is to absorb the harmful UV rays that are sent from the sun.
The ozone hole is the region over Antarctica with total ozone of 220 Dobson Units or lower. This map shows the ozone hole on October 4, 2004. The data were acquired by the Ozone Monitoring Instrument on NASA's Aura satellite.
MS: Scientists estimate that the hole in the ozone layer will be no more by the 2060s. However, it's very difficult to talk about complete recovery because the atmosphere itself is very different to what it was when there was no ozone depletion.
Without the ozone layer, the Earth's surface would be sterilized by UV radiation. The breakdown of the ozone layer increases skin cancer and cataracts in humans, impairs immune systems of all animals (including humans), and interferes with phytoplankton productivity in the oceans.
The discovery of the ozone layer hole in the 1980s promoted successful international cooperation to phase out the use of harmful chlorofluorocarbons (CFCs). Scientists say the ozone hole is continuing to shrink and could fully repair by 2050.
Australia's unusually harsh sunshine results mainly from its location in the Southern Hemisphere. The elliptical orbit of the Earth places the Southern Hemisphere closer to the sun during its summer months than the Northern Hemisphere during its summer.