1998 EARTH SCIENCE VIDEOTAPES |
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Tape Title | Record ID | Date Produced | TRT: |
Synopsis |
| 1998 ANTARCTIC OZONE HOLE LARGEST EVER | G98-045 | 10/6/98 | 00:09:05 | NASA and NOAA satellites show that the Antarctic ozone thinning covers the largest expanse of territory since the depletion developed in the early 1980s. The measurements were obtained this year between mid-August and early October
using the Total Ozone Mapping Spectrometer (TOMS) instrument aboard NASA's Earth Probe (TOMS-EP) satellite and the Solar Backscatter Ultraviolet Instrument (SBUV) aboard the NOAA-14 satellite.
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TAPE CONTENTS: |
| ITEM (1): 1998 ANTARCTIC "OZONE HOLE" (visualization) - NASA satellites show the size of the region of depleted Antarctic ozone (shown in blue) extended to a record 10.5 million square miles on Sept 19, 1998. The previous record of 10.0 million square miles was set in 1996. The Antarctic "ozone hole" develops each year between late August and early October. Regions with higher levels of ozone are shown in red.
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| ITEM (2): OZONE TRENDS - 1979 TO 1998 (visualization) - Yearly comparison of ozone levels in Antarctic. NASA and NOAA instruments have been measuring Antarctic ozone levels since the early 1970s. Large regions of depleted ozone began to develop over Antarctica in the early 1980s. Though "ozone "holes" of substantial size and depth are likely to continue to form during the next few years, scientists expect to see a reduction in ozone losses as levels of ozone destroying CFCs are gradually reduced.
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| ITEM (3): TOMS ANIMATION - The ozone measurements were collected by the Total Ozone Mapping Spectrometer (TOMS) aboard NASA's Earth Probe (TOMS-EP) satellite. NASAÕs TOMS instruments have been measuring Antarctic ozone levels since November 1978.
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| ITEM (4a): OZONE PROTECTS ANIMATION - Ozone protects the Earth by absorbing harmful ultraviolet radiation. The ozone molecule is split into one free oxygen atom and one molecule of ordinary oxygen. The free oxygen usually reacts with another oxygen molecule to reform the ozone molecule.
ITEM (4b): OZONE DESTRUCTION ANIMATION - Scientists say this year's abnormally cold Antarctic winter contributed to the ozone hole by activating more destructive chlorine. Chlorofluorocarbons (CFCs) lead to destruction of the protective ozone molecules located in the stratosphere. Chlorine atoms liberated from CFCs steal oxygen atoms, thus destroying the protective ozone molecule. One chlorine atom can destroy many thousands of ozone molecules over its lifetime in the stratosphere. The ozone hole appears because of the normally very cold Antarctic winter conditions.
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| ITEM (5): STRATOSPHERE ANIMATION - Most atmospheric ozone is found in the stratosphere -- in a thin layer 6 to 18 miles above the Earth's surface. The term "ozone hole" is used to describe a large area of intense ozone depletion that occurs over Antarctica during late August through early October and typically breaks up in late November. Ozone is a molecule that shields life on Earth from the harmful effects of the Sun's ultraviolet radiation.
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| ITEM (6): B-ROLL OF DR. PAUL NEWMAN IN LAB
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| ITEM (7): INTERVIEW - DR. PAUL A. NEWMAN, ATMOSPHERIC SCIENTIST, NASA GODDARD SPACE FLIGHT CENTER
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