For the first time, scientists have shown through direct satellite observations of the ozone hole that levels of ozone-destroying chlorine are declining, resulting in less ozone depletion.
For the first time, scientists have shown through direct satellite observations of the ozone hole that levels of ozone-destroying chlorine are declining, resulting in less ozone depletion.
Measurements show that the decline in chlorine, resulting from an international ban on chlorine-containing manmade chemicals called chlorofluorocarbons (CFCs), has resulted in about 20 percent less ozone depletion during the Antarctic winter than there was in 2005 — the first year that measurements of chlorine and ozone during the Antarctic winter were made by NASA’s Aura satellite.
“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 lead author Susan Strahan, an atmospheric scientist from NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
CFCs are long-lived chemical compounds that eventually rise into the stratosphere, where they are broken apart by the Sun’s ultraviolet radiation, releasing chlorine atoms that go on to destroy ozone molecules. Stratospheric ozone protects life on the planet by absorbing potentially harmful ultraviolet radiation that can cause skin cancer and cataracts, suppress immune systems and damage plant life.
Read more at NASA/Goddard Space Flight Center
Image: A view of Earth's atmosphere from space. (Credit: NASA)
