4 facts you might not know about ozone and the Montreal Protocol

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By www.noaa.gov

—The Montreal Protocol was adopted 35 years ago and remains a landmark environmental agreement, saving millions of people from cancer and contributing significantly to the protection of Earth’s climate system. Formally known as the “Montreal Protocol on Substances That Deplete the Ozone Layer,” this important U.N. treaty bans the release of harmful ozone-depleting chemicals such as chlorofluorocarbons, or CFCs.

Here are four facts about ozone, and the treaty that protects the ozone layer.

The view from an ozone balloon floating 100,000 feet above the Colorado Front Range. NOAA scientists based in Boulder, Colorado launch weekly balloons from sites all around the globe to monitor stratospheric ozone concentrations. Floating to over twice the altitude of commercial airliners, the curvature of Earth and inky black of space are clearly visible.
The view from an ozone balloon floating 100,000 feet above the Colorado Front Range. NOAA scientists based in Boulder, Colorado launch weekly balloons from sites all around the globe to monitor stratospheric ozone concentrations. Floating to over twice the altitude of commercial airliners, the curvature of Earth and inky black of space are clearly visible. (Patrick Cullis, Cooperative Institute for Research in Environmental Sciences)

1. The Montreal Protocol was written to address ozone depletion caused by industrial chemicals.

In the 1970s, scientists (including several experts from NOAA) discovered that an important function of the stratosphere performed by ozone was impaired by persistent, industrial chemicals known as chlorofluorocarbons (CFCs). These chemicals led to the destruction of  ozone molecules and depleted the layer that protects all life on Earth. One key concern was the large “hole” which was opening in the ozone layer each year over Antarctica.

Stratospheric ozone, which is found about 7-25 miles above the Earth, protects life on the Earth’s surface from the harmful effects of ultraviolet radiation, including skin cancer and weakened immune systems in humans. It also enables healthy ecosystems and productive agriculture.

Atmospheric scientists identified the actions that humans were taking to cause the stratospheric ozone depletion. Chlorine and bromine, released by the breakdown of CFCs, were particularly problematic. The 1987 Montreal Protocol phased out production and use of these and other substances that deplete ozone. These bans have had a significant, positive impact on the ozone layer.

DLR German Aerospace Center, CC BY 2.0 , 512px-Earth_from_space_7628218100 via Wikimedia Commons
from_space_7628218100 via Wikimedia Commons