2002 EARTH SCIENCE VIDEOTAPES |
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Tape Title | Record ID | Date Produced | TRT: |
Synopsis |
| TAKE TWO: INTERNATIONAL OZONE CAMPAIGN RETURNS TO ARCTIC CIRCLE | G02-090 | 01/06/03 | 00:10:21 | This month, the second version of the SAGE III Ozone Loss and Validation Experiment (SOLVE II) campaign begins to again tease apart details of ozone losses in the Arctic (SAGE III is the third Stratospheric Aerosol and Gas Experiment). SOLVE II scientists will work closely with European Commission scientists, sponsored by the Validation of International Satellites and Study of Ozone Loss (VINTERSOL) campaign. While the Arctic experiences smaller ozone losses than the Antarctic, Arctic ozone-depleted air can stretch over populated northern areas, allowing high doses of harmful ultraviolet radiation to reach animals and plants during Spring.
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TAPE CONTENTS: |
| ITEM (1): Scientists Return to the Scene - After measuring record low Arctic ozone levels in 2000, a group of international scientists returns to Kiruna, Sweden, in January 2003 for a second run of the project. The team will work to better understand processes leading to ozone loss near the North Pole by comparing satellite and ground-based measurements. The Arena Arctica facility at the Kiruna airport serves as hangar for the DC-8 operations and as base for balloon launches. Kiruna's extreme northern latitude allows measurements of the lower stratospheric polar vortex.
Courtesy: NASA
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| ITEM (2): Assessing Satellites - Scientists will again validate satellite data by comparing it to results from instruments aboard balloons and NASA's long range DC-8. This year, the researchers will focus on validating measurements from the third Stratospheric Aerosol and Gas Experiment (SAGE III) instrument aboard the Russian Meteor-3M spacecraft shown here.
Courtesy: NASA
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| ITEM (3): Low Levels of Arctic Ozone - While a large ozone 'hole' opens regularly over the Antarctic, warmer temperatures in the Arctic prevent a North Pole ozone hole from occurring as often. However, when large Arctic ozone losses occur, as they did here in the winter of 2000 (blue), the depletion can threaten populated areas with higher doses of ultraviolet rays. Ozone absorbs UV radiation, shielding life on Earth from the harmful rays. SOLVE II will again examine ozone losses over the Arctic this year. Here, data comes from the Total Ozone Mapping Spectrometer on the Earth Probe satellite.
Courtesy: NASA
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| ITEM (4): Polar Stratospheric Clouds - In the stratosphere, 15-50 kilometers (9-31 miles) above Earth, extreme low temperatures lead to the formation of polar stratospheric clouds. These clouds of nitric acid lead to the break down of ozone and allow harmful ultraviolet rays to reach Earth's surface. Extremely low Arctic temperatures enabled polar stratospheric clouds (PSCs) to last longer during the 1999-2000 winter, causing additional ozone loss.
Courtesy: NASA
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| ITEM (5): Mostly Cloudy - This sequence shows a calculation, based on temperature measurements, of ozone- destroying cloud presence in the Arctic from Nov. 1999 - March 2000. The SOLVE II scientists will also study these clouds during their mission at Kiruna, Sweden, the red dot on the map.
Courtesy: NASA
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| ITEM (6): Whirlwind - Swirling stratospheric winds around the North Pole in winter, called the polar vortex, confine cold air and provide conditions conducive to polar stratospheric cloud (PSC) formation. Warmer temperatures in the Arctic as compared to the Antarctic have historically prevented regular PSC and ozone 'hole' formation. SOLVE II scientists will examine whether conditions are changing.
Courtesy: NASA
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| ITEM (7): Ozone Loss - Intense ultraviolet (UV) radiation in the upper atmosphere produces ozone (O3). The radiation breaks typical oxygen molecules (O2) into free oxygen atoms (O). The free oxygen atoms (O) then join with molecular oxygen (O2) to form a molecule of ozone (O3). The ozone molecule generally absorbs UV, shielding the Earth from the harmful rays. Chemical reactions involving gases such as chlorine, bromine, nitrogen, and hydrogen destroy ozone as depicted here. Ozone depletion results from the combined actions of very cold conditions, the return of sunlight in the spring, and these chemicals, which come predominantly from human-produced compounds.
Courtesy: NASA
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| ITEM (8): Interview Excerpts With
Dr. Paul Newman, Atmospheric Physicist, GSFC
Courtesy: NASA
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