A United Nations scientific panel reports that the Earth’s protective ozone layer has begun to recover, in large part because the world has successfully phased out man-made halogenated hydrocarbons, including chlorofluorcarbons (CFCs), which used to be found in all aerosol sprays and refrigerators. These chemicals release chlorine and bromide, which destroy molecules far up in the atmosphere. The ozone layer protects the planet from solar radiation, which, in excess, leads to skin cancer and damage to plant life.
The Washington Post calls this a “rare piece of good news about the health of the planet.” This development proves that “when the world comes together, it can counteract a brewing ecological crisis.” Mario Molina, who won the Nobel Prize with F. Sherwood Rowland for anticipating the ozone problem, said: “It’s a victory for diplomacy and for science and for the fact that we were able to work together.” And former U.N. Secretary General Kofi Annan called the treaty behind this global action “perhaps the single most successful international agreement to date.”
In 1987, the leading producers of CFCs signed on to the UN-organized Montreal Protocol on Substances that Deplete the Ozone Layer, which established a novel, phased approach for reducing the production and use of CFCs. This treaty led to the creation of a multilateral fund, which has directed funds to developing countries. The goal was to transition away from CFCs to hydrochlorofluorocarbons (HCFCs), less active chemicals now also targeted for global phase-out, and hydrofluorocarbons (HFCs), which are not covered in the treaty, as well as other replacement chemicals.
Now, 35 years later, scientists can confirm there has been “sustained increase in stratospheric ozone.” In fact, over the past 13 years, ozone levels climbed 4 percent. Had the world not taken action, the UN reports, there would have been an extra 2 million cases of skin cancer per year by 2030.
Still, we have a ways to go. The ozone hole above the Southern Hemisphere has still not yet fully closed, and the overall layer is still 6 percent thinner than it was in 1980. The United Nation’s Environmental Program estimates that the ozone layer will be fully repaired by mid century.
According to Scientific American, the efforts to reduce the use of CFCs have an added bonus: “The phase-out also helped slow global warming because CFCs are also powerful greenhouse gases. In fact, the agreement to address the ozone hole has actually cut five times the greenhouse gas emissions as has the Kyoto Protocol to address global warming.” However, others argue the HCFCs and HFCs that have replaced CFCs are equally as harmful to the climate. These compounds are up to 10,000 times more potent than carbon dioxide in warming our atmosphere. The Montreal Protocol will phase out HCFCs by 2030, but puts no limit on HFCs.