07 Apr 2014:
Newfound Atmospheric 'Hole'
Threatens Polar Ozone Layer, Scientists Say
Markus Rex, AWI
West Pacific hole an elevator to the stratosphere
Researchers have discovered
a large opening in the Earth's atmosphere that is enabling pollutants to rise into the stratosphere and destroy ozone. The hole, which is in a part of the lower atmosphere called the "OH shield," is several thousand kilometers long and is centered over the tropical west Pacific Ocean. It's relatively close to Southeast Asia, a region with a booming population and rapidly increasing air pollution. The hole is a major concern because the OH shield usually scrubs air of chemical compounds emitted near the ground before they can reach the stratosphere, where those compounds can persist for long periods of time, reacting with and destroying ozone, say researchers at Germany's Alfred Wegener Institute who identified the hole. The newly discovered phenomenon acts as a sort of elevator, researchers say, drawing chlorofluorocarbons, sulfur dioxide, and other contaminants straight up to the stratosphere and bypassing the OH shield scrub.