The loss of the arctic ozone is caused by the extreme cold temperatures, sunlight and air pollutants. While the Montreal Protocol has severely cut back on the amount of air pollutants causing this effect, this year's dip in ozone over the arctic beats last year's 30% loss.

Associated Press - KBZK

"This is pretty sudden and unusual," said Bryan Johnson, an atmospheric chemist who works in the U.S. National Oceanic and Atmospheric Administration's Earth System Laboratory in Boulder, Colorado.

Atmospheric scientists concerned about global warming focus on the Arctic because that is a region where the effects are expected to be felt first.

"The Arctic stratosphere continues to be vulnerable to ozone destruction caused by ozone-depleting substances linked to human activities," the U.N. weather agency's secretary-general Michel Jarraud said.

Full article at