Ozone Hole Might Develop Soon Over Arctic

by Mark Bourrie

The report, released by Environment Canada, says the Arctic ozone holes could increase ultraviolet radiation that is "highly damaging" to life and cause the protective layer of the upper atmospheric layer over the rest of the northern temperate zone to become thinner.

The Canadian study looked at the rapid decline in ozone levels in the Arctic in the past 20 years. Scientists found that the ozone depletion of the past five years rivals the damage seen in Antarctica in the 1980s and 1990s, when ozone holes twice the size of Europe developed over the South Pole. The vortex itself collapses in early spring.

Last spring, ozone in the Arctic vortex region became so depleted that the Canadian government issued warnings to Inuit people in the high Arctic to take precautions against extremely elevated levels of ultraviolet rays.

Paul Coloja, president of the Kivalliq Inuit Association in Rankin Inlet, Northwest Territories, says the warnings show that the Arctic ozone crisis is worsening.

"It's a real threat to our people. We did not bring it upon ourselves. The industrialized nations must act quickly to clean it up, or our traditional way of life will be lost," he says. "Our people hunt in the high Arctic through months when the sun doesn't set.

"We are very worried about the effects of UV rays on our people and on the animals in the Arctic."

In the wake of the Montreal Protocol of 1987, which set limits on the amount of ozone-depleting chemicals that can be generated by signatory nations, environmental groups such as Greenpeace have been lobbying governments to meet those targets.

Greenpeace even developed the "Greenfreeze" refrigerator, which does not use ozone-degrading CFC gas in its coolant system. It also lobbied hard for controls on methyl bromide, a pesticide that does heavy damage to the ozone layer.

David Wardle, an Environment Canada physicist and chemist who worked on the new study, says the atmosphere over the Arctic could become much colder as the ozone layer over the North Pole erodes.

Much of that cooling would be in the stratosphere, where the place where ozone thinning occurs.

In the southern hemisphere, temperatures in the stratosphere fall to minus 80 centigrade in the late winter, allowing clouds of sulfuric acid, nitric acid and ice to form. The chemical reactions in these clouds are responsible for the Antarctic ozone hole, Wardle says.

Because of global warming, a similar upper atmosphere climate is developing in the Arctic, he says.

"The same process that makes it warmed on the surface of temperate regions makes it colder in the Arctic's stratosphere.

What we're seeing here is global warming possibly making the Arctic stratosphere as cold as the Antarctic's," Wardle adds.

"Global warning effects temperate regions much more than the polar areas and the tropics."

Wardle says scientists still have no idea how to get rid of the massive amount of chlorine that has drifted into polar regions.

Since research began in the 1970s, chlorine levels have jumped 400 percent.

"Some climatologists have suggested that the chlorine could react with benzene and propane. To get the amount of hydrocarbons you'd need to get rid of the chlorine, you'd have to fly every airplane we have into the arctic and have them cruise the stratosphere in perpetuity," he says.

"The only scenarios that we have are right out of science fiction. But levels of ozone-depleting gasses have been going up dramatically in this decade, and if nothing's done, we're going to have very serious damage to the Arctic in the next 20 years."

Aspects of the Canadian study confirm research done in Japan and the United States on the Arctic vortex, a body of cold air that is encircled by strong westerly winds. It forms in the winter, creating a barrier between the atmosphere of the Arctic and the air of the temperate regions. Bromine, chlorine and sulphur dioxide inside the vortex react with ozone, breaking it down.

The damage hasn't been limited to the Western hemisphere.

Satellite imagery shows an ozone-thin region tends to form most years over eastern Asia, especially in the region of the Kamchatka Peninsula. Japanese scientists have been following this trend with special interest, and, in early December, held a special conference on the problem.