Tweet
COLOGNE - Arctic winds have caused a hole in the atmosphere's ozone layer to form over central Europe, experts in Germany warned on Wednesday.
The Arctic winds, also linked to record-setting low temperatures across Europe in recent weeks, exacerbated the ozone depletions process, it was said.
According to findings obtained by high-altitude Russian research aircraft, nitrogen oxide and nitrogen dioxide gases in the upper stratosphere have climbed to the highest levels in at least two decades.
The increases have led to ozone reductions of up to 60 percent roughly 20 kilometres in altitude above the heart of Europe, said Marc von Hobe, a scientist with Germany's Juelich Research Centre.
"This decline was completely unexpected," he said. "The findings point out a critical need to better understand the processes occurring in the ozone layer."
Winds in the upper part of a massive winter low-pressure system that confines air over the Arctic region, known as the polar stratospheric vortex, sped up in February to become the strongest on record, he said.
The spinning vortex allowed the nitrogen gases, believed by the team to have formed at least 20 kilometres above the stratosphere as a result of chemical reactions triggered by energetic particles from the sun, to descend more easily into the stratosphere.
The increases in the two nitrogen gases - collectively known as NOx - are important because they are major players in the stratospheric ozone destruction process. A form of oxygen, ozone protects life on Earth from the harmful effects of ultraviolet radiation. The ozone layer has thinned markedly in high latitudes of the Northern and Southern Hemispheres in recent decades, primarily due to reactions involving chlorofluorocarbons and other industrial gases.
Scientists believe the 1987 Montreal Protocol, an international agreement that has phased out the production and use of such ozone- destroying compounds, may allow the protective ozone layer to be restored by the middle of this century.
Source : Expatica , 9 March 2005
The Arctic winds, also linked to record-setting low temperatures across Europe in recent weeks, exacerbated the ozone depletions process, it was said.
According to findings obtained by high-altitude Russian research aircraft, nitrogen oxide and nitrogen dioxide gases in the upper stratosphere have climbed to the highest levels in at least two decades.
The increases have led to ozone reductions of up to 60 percent roughly 20 kilometres in altitude above the heart of Europe, said Marc von Hobe, a scientist with Germany's Juelich Research Centre.
"This decline was completely unexpected," he said. "The findings point out a critical need to better understand the processes occurring in the ozone layer."
Winds in the upper part of a massive winter low-pressure system that confines air over the Arctic region, known as the polar stratospheric vortex, sped up in February to become the strongest on record, he said.
The spinning vortex allowed the nitrogen gases, believed by the team to have formed at least 20 kilometres above the stratosphere as a result of chemical reactions triggered by energetic particles from the sun, to descend more easily into the stratosphere.
The increases in the two nitrogen gases - collectively known as NOx - are important because they are major players in the stratospheric ozone destruction process. A form of oxygen, ozone protects life on Earth from the harmful effects of ultraviolet radiation. The ozone layer has thinned markedly in high latitudes of the Northern and Southern Hemispheres in recent decades, primarily due to reactions involving chlorofluorocarbons and other industrial gases.
Scientists believe the 1987 Montreal Protocol, an international agreement that has phased out the production and use of such ozone- destroying compounds, may allow the protective ozone layer to be restored by the middle of this century.
Source : Expatica , 9 March 2005
Comment