NASA Study Sheds Light on Ozone Hole Chemistry

Apr 29, 2010
Map of chlorine monoxide, the primary agent of ozone destruction in the Antarctic 'ozone hole,' as measured by the Microwave Limb Sounder instrument on NASA's Aura satellite at an altitude of approximately 18 kilometers (11.2 miles) within the ozone layer. Image credit: NASA/JPL

(PhysOrg.com) -- A new NASA study of Earth's polar ozone layer reinforces scientists' understanding of how human-produced chlorine chemicals involved in the destruction of ozone interact with each other.

A team of scientists led by Michelle Santee of NASA's Jet Propulsion Laboratory, Pasadena, Calif., examined how nighttime temperatures affect chlorine monoxide, a key chemical involved in . Combining NASA satellite measurements with a state-of-the-art chemical model, they found this relationship to be more consistent with recent laboratory work than with some older laboratory and field observational data. This verification is important, because scientists have not been able to conduct appropriate laboratory experiments relevant to understanding how polar chlorine monoxide behaves at night at the lowest temperatures of the stratosphere, Earth's second lowest atmospheric layer.

Santee and her team published their findings this month in the . The data came from the Microwave Limb Sounder instrument on NASA's Aura satellite.

"Our comprehensive study uses multiple years of Arctic and Antarctic satellite observations to quantify the nighttime balance of ozone-destroying chlorine ," said Santee. "By gaining a better knowledge of this balance, scientists will be able to make more accurate predictions of polar ozone loss, especially in twilight and in the Arctic, where conditions are often only marginally favorable for ozone destruction."

At night, chlorine monoxide molecules combine to form chlorine peroxide, and the balance between these two chemicals is highly temperature-sensitive. Studying this balance quantitatively is challenging. Previous studies in the laboratory and using aircraft and satellites had found significantly different degrees of balance. The Microwave Limb Sounder's very large number of measurements has quantified this balance far better than before.

The new research contributes to scientific understanding of the phenomenon more commonly known as the "ozone hole." Each year in late winter and early spring in the southern hemisphere, chlorine and bromine from human-produced compounds cause the nearly total destruction of ozone in Earth's stratosphere in a layer about 20 kilometers (12 miles) above Antarctica. These source gases that are responsible for the greatest destruction of the are now declining in response to the 1985 Montreal Protocol and its amendments.

Since its launch in 2004, the Microwave Limb Sounder has monitored most of the polar regions of both hemispheres daily, compiling tens of thousands of measurements of nighttime chlorine monoxide levels, along with various other chemicals, including . These data are allowing scientists to test their understanding of chlorine-related chemistry on an unprecedented scale.

Explore further: Magnitude-7.2 earthquake shakes Mexican capital

Related Stories

AURA satellite peers into Earth's ozone hole

Dec 07, 2005

NASA researchers, using data from the agency's AURA satellite, determined the seasonal ozone hole that developed over Antarctica this year is smaller than in previous years.

After Five Years, NASA's Aura Shines Brightly

Jul 16, 2009

(PhysOrg.com) -- On July 15, 2004, NASA's Aura spacecraft launched from California's Vandenberg Air Force Base on a mission to study Earth's ozone layer, air quality and climate. Aura's data are helping scientists ...

Study Finds Clock Ticking Slower On Ozone Hole Recovery

Jun 30, 2006

The Antarctic ozone hole's recovery is running late. According to a new NASA study, the full return of the protective ozone over the South Pole will take nearly 20 years longer than scientists previously expected.

Recommended for you

Magnitude-7.2 earthquake shakes Mexican capital

20 hours ago

A powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets. Some walls cracked and fell, but there were no reports of major damage or casualties.

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

THoKling
1 / 5 (3) Apr 29, 2010
Since NASA's attempts at climatology a while ago were deemed as grossly inaccurate when compared with data with other meteorological stations (something about Al Gore and the head of climatology there having a little deal going), I'm unlikely to pay any credence to information NASA has to offer in such matters.
CWFlink
1 / 5 (1) Apr 30, 2010
...another news-free article... Please stop posting non-news.

More news stories

Magnitude-7.2 earthquake shakes Mexican capital

A powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets. Some walls cracked and fell, but there were no reports of major damage or casualties.

China says massive area of its soil polluted

A huge area of China's soil covering more than twice the size of Spain is estimated to be polluted, the government said Thursday, announcing findings of a survey previously kept secret.

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.

Health care site flagged in Heartbleed review

People with accounts on the enrollment website for President Barack Obama's signature health care law are being told to change their passwords following an administration-wide review of the government's vulnerability to the ...