"It Looked As If Earth’s Ozone Layer Was Healing Nicely — Until Now"

"The rescue of the planet’s protective ozone layer has been hailed as one of the great success stories of modern environmental regulation — but on Monday, an international team of 22 scientists raised doubts about whether ozone is recovering as expected across much of the world.

“We’ve detected unexpected decreases in the lower part of the stratospheric ozone layer, and the consequence of this result is that it’s offsetting the recovery in ozone that we had expected to see,” said William Ball, a scientist with the Physical Meteorological Observatory in Davos, Switzerland.

In 1987, countries of the world agreed to the Montreal Protocol, a treaty designed to phase out chlorofluorocarbons, or CFCs, responsible for destroying ozone in the stratosphere. The protocol has worked as intended in reducing these substances, and early healing of the ozone “hole” over Antarctica has been subsequently hailed by scientists."

Chris Mooney reports for the Washington Post February 6, 2018.