Nature Nuggets: Ozone

Aug 18, 2023

It was the mid-1980s. Hairstyles were big and stiff, teased up inches above our heads and then held in place with super-stay hair spray brands like Aqua Net.

At about the same time in the decade of decadence, three British scientists discovered noticeable drops in ozone above Antarctica’s Halley Bay research station — losing as much as one third of its thickness compared to previous decades. In 1985, they published a paper suggesting a link to chlorofluorocarbons (CFCs), a human-made compound found in coolant and aerosol spray cans, like the cans used to dispense hair spray so teens everywhere could replicate Madonna’s tousled bob or the combed-forward look of Mike Score, the lead singer of Flock of Seagulls.

That thinning layer over Antarctica came to be known as the ozone hole. News outlets around the world started to report about the growing global crisis and the adverse effects humans and the environment would experience as a result of this depletion of ozone that blocks the sun’s damaging UV rays.

The U.S. Environmental Protection Agency reported that the reduction in the ozone layer of Earth’s atmosphere could lead to: increased levels of ultraviolet (UVB) radiation leading to increased severity of sunburns, non-melanoma skin cancer, malignant melanoma and cataracts; alter the cycles of important gases, such as carbon dioxide, carbon monoxide, and carbonyl sulfide; reduce phytoplankton, the foundation to the aquatic food web; and impact the early development of fish, shrimp, crab, amphibians and other marine animals.

Dr. Suzanne Metlay, who completed her ungraduated study at Harvard University and her PhD in geology and planetary science at the University of Pittsburgh, talked about the impacts of CFCs on the environment during her presentation, Ozone Hole Recovery: An International Success Story, Saturday, July 29 at the Estes Valley Memorial Observatory.

She asked six participants to join her at the front of the room where she instructed them to hold hands in groups of three. Each group represented three oxygen atoms bonded together. This is the configuration of an ozone molecule.

Metlay then picked out a young boy from the front row. He eagerly followed her instructions to run through each group and break up the handholding. The “broken atoms” were now instructed to hold hands in groups of two each.

“This is what happens when chlorine and bromine atoms come into contact with ozone molecules,” said Metlay. “The ozone molecules are broken apart.”

Ozone is a layer of molecules in Earth’s stratosphere that absorbs ultraviolet radiation, especially UVB rays, from the sun. When atoms, like chlorine and bromine, which are found in CFCs, destroy ozone molecules, the ozone layer breaks down faster than it regenerates. This process resulted in the ozone hole discovered over Antarctica.

Since the discovery of the hole, researchers now know that it grows and contracts with the seasons, becoming especially prominent in the Antarctic spring, when weather heats up and reactions between CFCs and ozone increase. Other areas of Earth’s ozone layer have also been observed to be thinning, including over Tibet and the Arctic.

But, as Metlay communicated during her talk, all has not been lost. The situation with the ozone holes actually created a rare opportunity for countries — even ones that are considered to be enemies — to work together to put a stop to the depletion of ozone in the stratosphere.

In 1987, 24 nations, including the U.S., The Soviet Union, Canada, Egypt and Japan, signed the Montreal Protocol, an agreement to eliminate the production and consumption of ozone depleting substances.

Today, the Montreal Protocol is signed by 197 countries — every member of the United Nations — making it the first U.N. treaty to achieve universal agreement.

Scientists have also reported that the ozone layer is shrinking, with projections showing that it will be fully healed by 2050. This will be achieved by halting the production and use of CFCs, with 98 percent of the chemicals identified in the treaty, including hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), already phased out by 2009.

According to an article in the January 2016 issue of Smithsonian magazine, if the Montreal Protocol had never been signed, the hole would have grown by 40 percent by 2013. It is truly an example of how working together — no matter what your perspective on your colleagues— can lead to positive results for everyone.

Dawn Wilson is the outdoor reporter for the Estes Park Trail-Gazette. She also guides in Rocky Mountain National Park, leads photo workshops throughout North and South America, sells prints of her photographs, and recently published 100 Things to Do in Estes Park Before You Die. To learn more about her work, visit www.DawnWilsonPhotography.com

Sign up for email newsletters