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Carbon Dioxide Essay, Research Paper
Carbon is the basis for all life on earth. This essay will explain the role of carbon
dioxide in v arious parts of the carbon cycle. This essay will examin three main, and
important parts of the carbon cycle, starting by explaning the role of the ocean in
obsorbing cabon. Next this essay will examin the human influences on the carbon cycle
and human production of carbon dioxide. Thiedly this essay will explain what controls the
carbon dioxide concentration.
The ocean holds a vast amount of carbon. Carbon dioxide in the atmosphere is
transferred into and out of the ocean continually, maintaining a balance by dissolving in
cold polar water. Plankton also play a large role in maintaning a cardon balance. Plankton
in the world oceans use carbon dioxide for growth (photosynthesis). Waste organic matter
sinks down from these ecosytems, carring cabon and nutrients away from the suface. As
on land, changes to either components of the ocean carbon cycle, chemical or biological,
have a great potential to modify climate change. Scientiests belive that the ocean currently
absorb 30-50 per cent of the cabon dioxide produced by the burning of fossil fuel. If they
did not soak up and carbon dioxide, atmospheric carbon dioxide levels would be much
higher then the current level of 355 parts per million by volume.1
The concentration of atmospheric carbon dioxide has been driven upwards over
the last 150 years by humans activities. Carbon emissions from the U.S. are now estimated
at 1.4 billion tons per year (that?s 5.4 tons per person!)2 Recall that northeastern forests
alone contain adout five times that amount in wood and biomass, and you begain to
appreciate their significance on global budgets.
There are two ways in which we affect the carbon cycle. First we add new
atmospheric carbon dioxide into the mix. Power generation and other fossil fuel emissions
release about 6 billion tons of carbon per year, would wide, to the atmosphere. Compared
to the amount added naturally every year, approximately 100 billion tons3, our
contribution is small. However, the new carbon is remaining and accumulating in the
atmophere.
Second, land use changes are converting forested systems, wich are carbon sinks,
into agricultural and urban zones, which tend to be carbon sourse. For example, tropical
forests losses are estimated to add 1 billion tons of carbon per year4. Perhaps more
important, the opporunity to remove cardon dioxide from the atmosphere is greatly
reduced when the forests disappear.
Carbon dioxide is a greenhouse gas, which means that it adsords heat reflected
from the earth?s surface and prevents the escape of heat into space. A delicate balance has
developed on earth, one that permits a wide variety of life forms to coexist. Too little heat
trapping results in a cold planet. Too much heat trapping results in a more energetic
atmosphere, and a less stable climate. The average surface temperature of the earth has
risen along with atmospheric carbon dioxide concentration in both the distant and the
recent past.
Humans play the largest role in the production of carbon dioxide. In 1995 the
emissions of carbon dioxide into our atmophere rose by 2 percent. Many say that the
soden increase was caused by a hot summer and cold winter with more people burning
gas. This was the largest jump in carbon dioxide emissions ever.5 Canadian carbon dioxide
emissions are mostly (98.5 percent) accounted for by the combustion of fossil fuels.6
Fossil fuels are of considerable economic value and their consumption is carefully
monitored, energy-related carbon dioxide can be estimated more reliably than any other
emissions source.
The atmosphere?s carbon dioxide concentration has risen about 30 per cent since
preindustrial times, enhancing the natural green house effect. The prediction of future
climat change requires quantitative of the sources and sinks of carbon dioxide, and thier
contritributing natural and human influences. There is a natural cycling of carbon in the
environment, causing a large exchange of carbon among the atmosphere, the land
vagetation and soil, and the ocean marine biosphere. Evidence from ice core data suggests
that this natural cycle has been roughly in balance, with olay minor variation, since adout
10 000 years ago.