NOAA, NSF OBSERVE 20TH ANNIVERSARY OF OZONE HOLE 'SUCCESS STORY'
August 22, 2006 — Twenty years ago this month, four teams of scientists from NOAA, NASA and two universities arrived in Antarctica seeking to determine the cause of a "hole" in the Antarctic ozone layer. Their efforts helped determine the chemical basis for the ozone loss and formed the scientific basis for the resulting international treaty phasing out the production of chlorofluorocarbons, or CFCs, which has led to a decline in ozone-depleting gases. (Click NOAA satellite image for larger view of the most recent analysis of the Southern Hemisphere total ozone from the an instrument on board the NOAA polar orbiting satellite. In austral spring the analysis shows the "ozone hole" (values below 220 Dobson Units) over Antarctica and the Antarctic Ocean. Click here for latest view. Please credit “NOAA.”)
Two of the scientists observed the milestone during a news conference today in Washington, D.C., which also previewed a number of polar activities to be conducted during the International Polar Year. The National Science Foundation is the lead U.S. agency for IPY.
"The discovery of ozone depletion and the response of the scientific community constitute nothing less than a scientific success story," said Susan Solomon, winner of the 2004 Blue Planet Award and the 1999 National Medal of Science for her work.
The work by the team provided the scientific basis for the Montreal Protocol on Substances That Deplete the Ozone Layer, an international treaty begun in the late 1980s designed to protect the ozone layer by phasing out the production of ozone-depleting substances. (Click NOAA aerial photo for larger view of South Pole Observatory taken in 2004. Please credit “NOAA.”)
Solomon was an atmospheric chemist at NOAA's then-Aeronomy Laboratory in Boulder Colo. when she led the NOAA team. David Hofmann, then with the University of Wyoming, headed the UW team. Both were funded by NSF, which operates the McMurdo Station at the South Pole. Researchers from NASA and the State University of New York (SUNY) at Stoneybrook, rounded out the scientific party. Solomon, now a NOAA senior scientist, and Hofmann, now director of the Global Monitoring Division, both work at the NOAA Earth System Research Laboratory in Boulder, Colo.
"This is an example of the quality science conducted by NOAA scientists and their colleagues, often in extreme conditions, and how it informs those who make decisions that affect our daily lives," said retired Navy Vice Adm. Conrad Lautenbacher, Ph.D., undersecretary of commerce for oceans and atmosphere and NOAA administrator. "Through this work, we gained a better understanding of our atmosphere, which is a key element of NOAA's mission." (Click NOAA photo for larger view of atmospheric sampling balloon being deployed in the South Pole Observatory in 2004. Please credit “NOAA.”)
The ozone layer is a thin, invisible layer of the Earth's atmosphere about 15 miles thick. A British Antarctic Team first looked at results that showed a decline in stratospheric ozone over Antarctica in 1985, and doubted their findings. After rechecking their data and their instruments, they determined that there was a hole in the ozone.
"The hole isn't a hole but more of a wafer as thick as Mount Everest and as wide as the United States," said Hofmann in a 1987 NOVA television program "The Hole in the Sky."
Theories about the cause included solar activity that affected the magnetic field, atmospheric motions and chemical reactions involving chlorofluorocarbons (CFCs), which had been used since the 1930s as refrigerants and propellants, such as aerosol sprays. (Click NOAA photo for larger view of the night sky from the South Pole Observatory taken in 2004. Please credit “NOAA.”)
The work conducted by the Antarctic team in the 1986 field study was the first to show that a chemical reaction triggered by the CFCs was indeed the cause. Scientific papers have been published recently showing early signs of a leveling off of ozone loss, linked to the success of international agreements to control CFC emissions worldwide.
Part of NOAA's global environmental observing mission is to continue monitoring ozone and ozone-depleting gases. NOAA has a new Ozone Depleting Gas Index, a number based on NOAA's measurements of all the ozone-depleting gases that indicates how far along we are towards pre-ozone hole conditions. Hofmann said the ODGI indicates that the ozone-depleting potential of the gases has already declined, in agreement with the early signs of leveling off of ozone loss and the success of the Montreal Protocol. (Click NOAA photo for larger view of croquet being played outside the South Pole Observatory in 2005. Click here for high resolution version. Please credit “NOAA.”)
In 2007 NOAA, an agency of the U.S. Commerce Department, celebrates 200 years of science and service to the nation. Starting with the establishment of the U.S. Coast and Geodetic Survey in 1807 by Thomas Jefferson much of America's scientific heritage is rooted in NOAA. The agency is dedicated to enhancing economic security and national safety through the prediction and research of weather and climate-related events and information service delivery for transportation, and by providing environmental stewardship of the nation's coastal and marine resources. Through the emerging Global Earth Observation System of Systems (GEOSS), NOAA is working with its federal partners, more than 60 countries and the European Commission to develop a global monitoring network that is as integrated as the planet it observes, predicts and protects.
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