2001 EARTH SCIENCE VIDEOTAPES |
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Tape Title | Record ID |
Date Produced | TRT: |
Synopsis |
| CARBON MYSTERY LEADS TO NORTHERN FORESTS
| G01-086 | 12/11/01 |
00:05:04 | New research has found that forests in
America, Russia and Europe have been storing nearly 700 million
metric tons of carbon a year during the 1980s and 1990s, answering a
long-standing mystery of where some 15-30% of industrial carbon
emissions are absorbed. By tracking the global carbon cycle,
scientists can better predict future levels of carbon dioxide in the
atmosphere and answer questions about possible future impacts of
global climate change.
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TAPE CONTENTS: |
| ITEM (1): Pulse of The
Planet - The land and oceans are known to store half of the
total carbon emitted annually from fossil fuel burning and industrial
activities. The other half is accumulating as carbon dioxide in the
atmosphere, which is thought by many to be responsible for global
climate change. Researchers found that America's forests soaked up
140 million tons of carbon a year, while most Canada's boreal forests
were found to be losing carbon. Russia, the country with most
forests, accounted for almost 40 percent of the biomass carbon sink.
Satellite observations of vegetation greenness is a measurement of
the amount and functioning of plants which consume atmospheric carbon
dioxide and synthesize sugars. Watching the greening over the three
years shown is a good indication of carbon fixation.
Courtesy: NASA / ORBIMAGE
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| ITEM (2): The Carbon
Cycle - The carbon cycle on land, acted out here show a tree
taking in carbon dioxide from the atmosphere, and combined with water
and nutrients from the soil, growing. In the fall and winter, parts
of the growth die off and release some carbon back into the system.
At some point, the tree is no longer able to take in carbon and
begins to die. When that happens, all the carbon absorbed in its body
is released back into the cycle as it decomposes. Fire can accelerate
this, sending plumes of carbon-laden aerosols into the atmosphere, as
well as leaving carbon-rich ash deposits on the ground for further
decomposition and recycling.
Courtesy:NASA
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Earth Science Gallery