When the world comes together, it can actually solve big problems. A typical example: The ozone hole, which, if all goes according to plan, could be cured in the 2060s, says a new report by the United Nations.
According to the report, a decade-long international treaty bans ozone – Chemical degradation has led to its decline, and "much heavier ozone depletion in the polar regions has been avoided." There is still a lot to do, but this definitely falls into the category "Good News".
Turning point, "said Paul Newman, a scientist who directs NASA Ozone's Watch and led the UN report, to Earther.
The report appears every four years, and this is the fifth iteration The Ozone Hole is powered by a range of chemicals commonly found in aerosol cans, air conditioners, and refrigerators called chlorofluorocarbons and chlorofluorocarbons, which release chlorine in the stratosphere. If this is the case, more ultraviolet light from the sun reaches the surface, increasing the risk of bad things like skin cancer, and the problem was particularly noticeable in the Antarctic, where an ozone hole formed every spring.
The scientists identified the chemicals as problematic, and the poli The decision-makers actually responded. The Montreal Protocol was colored in 1987. After 30 years, the ozone hole is still an annual occurrence. However, the new report definitely complements a 2016 study that said the ozone hole has been on the mend recovery since 2000. If everything goes according to plan, the ozone levels in the region could return to the pre-hole state within 40 years.
In regions where ozone depletion was less pronounced, the return to normal could be even earlier. The Arctic and mid-latitudes of the northern hemisphere could reach there in the 2030s, and the mid latitudes of the southern hemisphere could reach ozone levels of the 1980s by the middle of the century.
To Achieve This Timeline of Ozone Recovery The world needs to continue working to reduce other ozone depleting chemicals, and does not need to throw another key into the recovery process. At some levels there are some warning signs that scientists observe.
The first is a mysterious upward trend in CFC-11, a chemical banned under the Montreal Protocol. Although banned, studies released earlier this year have shown that they have been on the rise since 2012. Most signs point to China as the perpetrator of illegal emissions and must be stopped to keep the recovery on track.
Another factor is happening with the fight against global warming. The ozone hole and climate change are generally separate issues, but they overlap a bit. The lower greenhouse warming effect associated with elevated greenhouse gases also causes cooling in the stratosphere, which is about 6 to 12 miles above the surface of the planet. This can slow down the ozone depletion process, which could accelerate recovery in some places.
At the same time, the report states that increased warming due to greenhouse gases alters the planetary circulation in the atmosphere in a way that can lead to less ozone in the tropics and more in the Arctic and mid-latitudes. Curbing greenhouse gas emissions – including those caused by replacing ozone-depleting chemicals – is therefore likely to still be a good idea.
The last question is perhaps the most disturbing, because we know so little about it. The report raises concerns about what would happen if the world, or even a rogue state, decided to cool the planet by sending tiny particles into the stratosphere. The process known as geoengineering is impacted here with potential consequences and would probably also be located in the stratosphere.
"The problem is that our knowledge about the natural levels of stratospheric particles is not that high," Newman said. "Geoengineering poses quite a challenge by disrupting the natural amount of stratospheric particles and additionally affecting ozone."
So let's not do that and instead try to fix the ozone hole and global warming here to loosen on the ground