Polar researchers probe ozone-destroying clouds

Ellesmere study to measure effects of climate change on atmospheric layer

By -none-


Research that begins this month at a lab on Ellesmere Island could shed light on how climate change may slow the repair of the ozone hole.

The Polar Environment Research Lab, or PEARL, located near the Eureka weather station, has a wide array of gadgets to gather information from a column of air that stretches 100 kilometres into the sky.

These tools will be used during International Polar Year, which kicked off earlier this month, to examine one of the stranger consequences of a warming climate: the upper atmosphere, known as the stratosphere, is expected to become colder.

And cold weather up there could mean it will take a lot longer for the ozone hole to repair itself.

During the winter, temperatures in the stratosphere above the North Pole dips to -90 C, due to the absence of sunlight, and because of ferocious winds that form a “polar vortex” that lock the cold in.

ITK Job Opportunties, Senior Policy Advisor, MMIWG

All these ingredients create a special kind of cloud, found 20 kilometres above the Earth’s surface, known as polar stratospheric clouds. They’re also sometimes called mother of pearl clouds, because of their streaky, translucent appearance.

These clouds are important because they help start a chemical reaction that causes chlorine to destroy ozone.

The ozone layer helps filter out ultraviolet rays from the sun before they reach the surface of the Earth. Ultraviolet rays are believed to cause skin cancer.

The ozone hole is primarily found over Antarctica, although a smaller “dimple” is found over the Arctic.

The shrinking of the ozone hole is considered to be under control, thanks to the Montreal protocol, signed in 1989 by many countries, which led to the phasing out of chemicals that contribute to ozone destruction, such as chlorofluorocarbons, or CFCs, found in old refrigerators.

But ozone shrinking could still be occurring three times faster than originally thought, according to some research that has taken into account the effects found in the polar vortex each winter.

Online survey on cannabis for University of Waterloo

Keeping an eye on ozone levels above the North Pole is just one purpose for PEARL over the next few years. And researchers who work at the lab want to involve Nunavut residents, said Dr. Kaley Walker from the University of Toronto.

During IPY, one northern research assistant will be hired to work at PEARL.

As well, a dozen students who enter an essay-writing contest will be selected to visit PEARL during the summer of 2008.

“We have such an amazing experience when we come up here. Why can’t we share with this other people?” Walker asked.

For the last four years, atmospheric researchers have visited Resolute’s school to explain their research to students.

Last year they also visited Grise Fiord. And they plan to increase community visits for the polar year, with four more community visits planned this year, to Pond Inlet, Igloolik, Arctic Bay and Clyde River.

To collect their data, researchers at PEARL use tools such as a spectrometer, which examines light, to discover changes in temperature and air pressure. “It’s like a really, really, really good prism,” Walker said.

Some equipment can examine the chemical makeup of the atmosphere, based on the colour of light.

“It’s like a fingerprint in the sunlight,” Walker said.

More information is gathered by shooting high-powered lasers into the sky. This light reflects off snow crystals in the sky and scatters back down to be measured.

Data collected during IPY will be matched against records collected at the lab, which go back to 1993.

Another offshoot of research will look at how different contaminants travel from the South to the northern atmosphere.

Ellesmere Island poses its own special challenges to researchers. To begin, PEARL is powered by what could be the longest extension cord in the country, which stretches 15 kilometres, from the Eureka weather station to the research lab.

And radar dishes at the site have recently been cordoned off with snow fencing to prevent muskox from rubbing against the precisely positioned equipment.

“You have to animal-proof them,” Walker said. “A ‘keep out muskox’ sign won’t work.”

Share This Story

(0) Comments