Taking action to protect our planet can seem like a daunting or even futile task. Scientists have to navigate a complicated ecosystem with many interwoven variables in order to link an effect (like increased droughts or unusually intense storms, for example) with a cause. Politicians spanning many countries and cultural differences then have to come up with a plan, and entire industries have to agree to invest in that plan.
As we ring in the new year of 2017, let’s look at one of my favorite science stories from 2016: a story that tells us that all of that is possible. Science can save the world, with a little help, of course, from the cooperation and investment of its inhabitants.
What caused the hole in the ozone layer?
In 1985, a trio of British researchers noticed a hole in the ozone layer, our protection against harmful UV rays, over the Antarctic. Almost ten years earlier in 1974, scientists had noted a link between possible damage to the ozone layer and the release of chlorofluorocarbons in to the atmosphere, work which later earned those authors, Mario Molina and Sherwood Rowland, along with Paul Crutzen, the Nobel Prize in Chemistry.
In the 1970s and 1980s, chlorofluorocarbons or CFCs were readily used in coolants for refrigeration systems and everyday propellants like hair sprays or other aerosols. CFCs are fairly stable molecules so, once released, they almost always make their way up into the stratosphere, the layer of the Earth’s atmosphere that starts about 10-20 kilometers up (depending on where on Earth you’re located). They do not stay trapped inside the walls of your apartment, as has been incorrectly suggested by the US president elect.