2000 EARTH SCIENCE VIDEOTAPES |
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Tape Title | Record ID | Date Produced | TRT: |
Synopsis |
| INTERNATIONAL CAMPAIGN OBSERVES SIGNIFICANT ARCTIC OZONE LOSS
| G00-035 | 04/05/00 | 00:09:54 | During the preceding winter Arctic ozone levels reached their lowest point in eight years at an altitude of nearly 60,000 feet. But measurements from a recent international mission are yielding better insights into the processes that control polar ozone. Called SOLVE (Stratospheric Ozone Loss and Validation Experiment), it included researchers from Europe, Russia, Canada, and the United States working together to develop better tools for predicting the state of polar ozone levels. These tools will become more important in light of expected chlorine level declines due to the Montreal Protocol and what will likely be increasing levels of greenhouse gasses in the coming decades.
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TAPE CONTENTS: |
| ITEM (1): A Gap in the Churning Sky - A combination of factors contributed to the dramatic drop in Arctic stratosphere ozone levels. Despite the very dry conditions in the polar stratosphere, temperatures plunged far enough to enable the formation of Polar Stratospheric Clouds (PSCs) at an unusually early date. PSCs are necessary for the conversion of chlorine from benign molecular forms into chlorine monoxide, an ozone destructive compound.
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| ITEM (2): The Arctic Ozone Low (Slo-mo) - The ozone anomaly, shown by the changing blue field near the North Pole, is the difference between ozone levels observed in the early 1980's and this last winter.
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| ITEM (3): The Polar Vortex - During winter, stratospheric winds tend to form a vortex around the North Pole. This becomes a container for cold, high altitude air where ozone is lost due to chemical changes motivated by the creation of clouds in the stratosphere. Measurements of atmospheric ozone were taken by NASA's high altitude ER-2 aircraft, and the space agency's DC-8. Readings from NASA's Total Ozone Mapping Spectrometer (TOMS) Earth Probe showed a clear ozone minimum over the polar region during February and March.
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| ITEM (4): Ozone Loss - During winter, stratospheric winds tend to form a vortex around the North Pole. This becomes a container for cold, high altitude air where ozone is lost due to chemical changes motivated by the creation of clouds in the stratosphere. Measurements of atmospheric ozone were taken by NASA's high altitude ER-2 aircraft, and the space agency's DC-8. Readings from NASA's Total Ozone Mapping Spectrometer (TOMS) Earth Probe showed a clear ozone minimum over the polar region during February and March.
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| ITEM (5): Deployment Site - Kiruna, Sweden was chosen as the deployment site for SOLVE for two reasons. First, the Arena Arctica facility at the Kiruna airport is a superb hanger for the ER-2 and DC-8 operations. Second, Kiruna's extreme northern latitude is ideally located for measurements of the lower stratospheric polar vortex. Kiruna is marked by the black point on the map, and a 2000 km circle is drawn around town, illustrating the range of both the ER-2 and DC-8 during this mission.
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| ITEM (6): Scientist B-Roll - The following b-roll shows researchers affiliated with the SOLVE project working in Kiruna, Sweden.
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| ITEM (7): Solving the Ozone Puzzle (Voice Over) - Ozone is vital to life on earth because it blocks harmful ultra-violet radiation from the sun. To better understand the nature of atmospheric ozone, a team of international researchers converged on the Swedish town of Kiruna, located far in the north. The mission was called "SOLVE", the Stratospheric Ozone Loss and Validation Experiment. What they found suggests that ozone loss may increasing. Using instruments flown on sophisticated aircraft, balloons, and orbiting spacecraft, experts now believe that super-cold temperatures in the arctic stratosphere may be causing the formation of a type of cloud essentially lined with ozone destructive molecules. Scientists say this complex cooperative experiment will help them develop predictive models about how the Earth's atmosphere will behave as greenhouse gases
rise in coming decades.
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| ITEM (8): Interview Excerpts - Dr. Paul Newman, Atmospheric Scientist, NASA/GSFC
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