No risk of ozone hole above Arctic - claim

The reported risk of a hole in the ozone layer appearing over the Arctic this winter has been overstated, a Swedish researcher said on Wednesday.

"The stratosphere in the Arctic region has been unusually cold this winter," said Donal Murtagh, a professor of global environmental measurements at the Chalmers University of Technology in Goteborg.

Murtagh also is the lead director for atmospheric science research for the Swedish orbital observatory Odin, which orbits the poles.

Ozone, a form of oxygen, helps protect the Earth from some of the damaging ultraviolet radiation from the sun. The reduction of ozone has led to fears of more skin cancer and other problems in affected areas.

Low temperatures this year have created large amounts of ozone-destroying chlorine compounds in the stratosphere at the end of January, which resulted in reports of the likely appearance of an "ozone hole," he said.

Using the satellite, and computers on the ground, he said researchers have found that the threat of such a hole was unlikely, unless temperatures remain cold beyond winter.

"Only renewed cooling of the stratosphere could change the situation, but it is hard to see how this could happen," he said.

Launched in 2001, Odin is the only satellite to have mapped the amount of chlorine in the ozone layer.

The primary purpose of its ozone studies is not to verify the existence of holes, but to unravel the mechanisms behind their appearance.

Besides Sweden, France, Canada and Finland are involved in the project, named for the chief deity in Norse mythology.

Odin was designed and developed by the Swedish Space Corporation and its operations are based at the Esrange rocket launching pad near Kiruna, about 1 230km north of the capital.