Arctic Ozone Loss Raises Concern
By Associated
Press
03 March,2005
Associated Press
WASHINGTON -- Ozone levels over the Earth's far north dipped
sharply early last year when polar winds trapped nitrogen pollutants,
researchers reported Tuesday.
The sun contributed
to the problem, sending out a storm of particles that bombarded the
Earth and helped generate some of the ozone-destroying chemicals, according
to the report in Geophysical Research Letters.
Declines in ozone
over the South Pole have raised concern in recent years. They were blamed
on chemicals used in aerosol sprays. Since those chemicals were widely
banned, ozone levels have risen in the Antarctic.
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.
The decline had
been less dramatic in the north, but in February and March of 2004 a
decline of up to 60 percent was measured, according to a team of researchers
led by Cora Randall of the University of Colorado at Boulder.
"This decline
was completely unexpected," Randall said in a statement. "The
findings point out a critical need to better understand the processes
occurring in the ozone layer."
Winds 20 miles above
the Earth's surface became much stronger than usual, the researchers
said. Those winds formed a vortex, or circle, allowing nitrogen oxide
and nitrogen dioxide gasses that had formed as a mass of energetic particles
bombarded the Earth solar storm in the fall of 2003 to descend and react
with the ozone layer.
The 2004 ozone decline
occurred over the Arctic and the northern areas of North America, Europe
and Asia.
The research was
funded by NASA, the European Union Commission and the European Space
Agency.
Working with Randall
in the study were researchers from the United States, Canada, Norway
and Sweden.
© 2005 The
Associated Press