NASA shows signs that the hole in the Earth's ozone layer is shrinking, proving that humanity's plan to save the world is working.
NASA said in November last year that the ozone hole in Antarctica was at its smallest since 1988. It used satellite observations to provide the first direct proof of the ozone layer's recovery.
Ozone Layer Recovering Due To Chemicals Ban
Using measurements from NASA's Aura satellite, NASA discovered that the decline in chlorine has led to an around 20 percent decrease in ozone depletion over the Antarctic winter compared to 2005. It is the year that the satellite started measuring chlorine and ozone in every Antarctic winter.
These were also the first measurements on the ozone hole's chemical composition that showed decreased levels of ozone depletion. The study detailing the discovery was published in the Geophysical Research Letters journal on Jan. 4.
The chlorine decline was attributed to the international ban on chlorofluorocarbons, which are long-lived, man-made chemicals that greatly contribute to ozone depletion. CFCs rise to the Earth's stratosphere, where the ultraviolet radiation from the Sun breaks apart the chemical to release chlorine atoms that destroy the ozone molecules.
"We see very clearly that chlorine from CFCs is going down in the ozone hole, and that less ozone depletion is occurring because of it," said Susan Strahan, an atmospheric scientist from the Goddard Space Flight Center of NASA and the lead author of the study on the ozone layer's recovery.
The Success Of The Montreal Protocol
The recovery of the ozone layer is crucial to the Earth's survival as ozone molecules at high altitudes absorb the Sun's harmful radiation to protect our skin and eyes.
In the early 1980s, scientists discovered that CFCs found in substances, such as refrigerants and hair sprays, were the main culprit in ozone depletion. The whole world banded together in 1987 and signed the Montreal Protocol, which banned the use of the ozone-killing chemicals.
Just over 30 years later, NASA has now provided direct proof that the Montreal Protocol is working. The ozone layer is not fully out of the woods though, as it will take decades before the hole is completely healed.
According to Strahan's colleague and a co-author of the study, Anne Douglass, the ozone hole might not be fully patched up until about 2060 to 2080. Nevertheless, the Montreal Protocol is now considered to be the most successful environmental agreement between nations in the history of mankind. Hopefully, others will follow and help make the Earth a better place for future generations.