01-28-2007
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County Council Member
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Member Since: May 2006
Location: UK
Posts: 276
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Re: Ski resorts affected by climate change
NASA
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In the past 200 years, atmospheric CO2 levels have increased by a quarter, going from 0.028% around 1700 to 0.035% in 1995. This increase has been caused by growing human populations using and burning increasing amounts of coal, oil and gas. Also, deforestation puts additional CO2 in the atmosphere, by burning of trees and by disturbing vegetation and soil dynamics, which permits the detritus of forest clearing to decompose and to oxidize the soil carbon.
However, when these sources of CO2 are tallied up, they are more than double the observed increase of CO2 in the atmosphere. Some of the anthropogenic CO2 is absorbed by the ocean, and the rest by the vegetation and soils. But how much? where? and by what mechanisms? Places where the CO2 winds up are termed "sinks". It is important to know how the anthropogenic CO2 sink is partitioned between land and sea because the lifetime of a molecule of carbon in vegetation is 10-100 times shorter than in the ocean. Thus, the CO2 that has gone into the land's biosphere may not stay there for long.
NASA GISS: Science Briefs: Oh Where Oh Where Does the CO2 Go?
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DOE
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While these natural processes can absorb some of the net 6.1 billion metric tons of anthropogenic carbon dioxide emissions produced each year (measured in carbon equivalent terms), an estimated 3.2 billion metric tons is added to the atmosphere annually. The Earth’s positive imbalance between emissions and absorption results in the continuing growth in greenhouse gases in the atmosphere.
Greenhouse Gases, Climate Change, and Energy
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NOAA
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between 200 to 280 parts per million (ppm). As a result of the industrial and agricultural activities of humans, current atmospheric CO2 concentrations are around 380 ppm, increasing at about 1% per year. Over the past two decades, only half of the CO2 released by human activity, the so-called “anthropogenic CO2,” has remained in the atmosphere; about 30% has been taken up by the ocean, and 20% by the terrestrial biosphere. The atmospheric concentration of carbon dioxide is now higher than experienced on Earth for at least the last 400,000 years, and is expected to continue to rise, leading to significant temperature increases by the end of this century.
Impacts of Anthropogenic CO2 on Ocean Chemistry and Biology
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