WORLD
Arctic ozone loss `unprecedented,` scientists say
Baku, January 20 (AZERTAC). Unusual winter weather in the atmosphere high above the Earth`s surface caused an "unprecedented" loss of protective ozone over the Arctic this year, scientists say.
The ozone layer in the stratosphere, located about 15 to 35 kilometres above the Earth`s surface, protects the Earth from the sun`s ultraviolet rays and harmful effects such as skin cancer. While an ozone hole has formed in the stratosphere over the Antarctic each spring since the mid 1980s, a paper published in Nature on Sunday marks the first time scientists have reported a comparable loss over the Arctic.
"We`ve seen something unprecedented," said Kaley Walker, a University of Toronto atmospheric scientists who was part of the international team that conducted the study.
"The amount of depletion and how little ozone there was over certain altitudes is something we haven`t seen before."
The team concluded that the huge amount of ozone loss was linked to a period of extreme cold in the stratosphere that lasted 30 days longer this year than in any previously studied Arctic winter.
Cold weather in the stratosphere does not necessarily reflect cold conditions on the surface, and in fact is often linked to warmer surface temperatures. Average temperatures in the Arctic have warmed significantly faster than in other parts of the world in recent decades.
