Реферат на тему Global Warming Essay Research Paper
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Global Warming Essay, Research Paper
Global Warming may not be on the tip of everyone’s tongue, nor in the foremost part of
their minds. In fact, Global Warming may not even exist. Yet its consideration is worth the
taking since it could have profound impacts on the Earth, the only planetary home humans
possess.
Global Warming is, by the EPA definition, the progressive gradual rise of the earth s
surface temperature thought to be caused by the greenhouse effect and responsible for changes in
global climate patters the term is most often used to refer to the warming predicted to occur as a
result of increased emissions of greenhouse gasses. This is not used synonymously with concept of
the Greenhouse Effect, the natural process that has kept the Earth s temperature about 59 degrees
F warmer than it would otherwise be. Current life on Earth could not be sustained without the
natural greenhouse effect. The natural Greenhouse Effect is not an environmental concern,
whereas an Enhanced Greenhouse Effect, the increase of greenhouse gas concentrations from
anthropogenic activities, and Global Warming are considered to be.
While scientists still debate on whether Global Warming is an actual occurrence, there is
evidence of a warming trend in the Earth s climate. Records show a sharp increase in temperature
mean over the past decade, which is part of an upward slope beginning from the Industrial
Revolution. The melting at the polar icecaps shows further indication of an over-all warmer
climate. The thickness of the Arctic polar cap alone “declined by 4.3 feet, or 40 percent, between
1958 and 1997″ (1 ). More recent weather appears to be more turbulent as well, with storm systems
such as El Nino and El Nina ravaging the Western Hemisphere. Though there are some global
signs as well, such as an increase in the cases of skin cancer. This is not only a health concern, but
shows that more of the harmful ultraviolet radiation pouring down on the Earth from the sun is
passing through the protective layers of the Earth s atmosphere, bringing an increase of heat that
will be expelled or trapped. Scientists believe Global Warming to be a likely cause for these
transpirations.
Although there are many who believe in Global Warming s existence and pertinence,
skeptics that disagree with this view maintain that the warmer temperatures are a result of a
natural cycle. Charts graphing temperature data well back into the history of the earth show a
previous increase in mean, global climate. Since there was no Industrial Revolution back then and
human activity did not exist, it would be incorrect to attribute the change in temperature to
man s interference. Events like the Ice Age and the Little Ice Age, the cooling of the climate by +
degrees Celsius in the years 1400 AD to 1860 AD, show that the Earth s climate entertains the
propensity for dynamic changes and trends, one of which it may be involved in now. Some
scientists theorize that the rise in temperature may even be a result of increased solar activity of
the sun.
Despite the argument on the validity of Global Warming, there is an agreement that an
ambiguous correlation exists between rising temperatures and concentrations of carbon dioxide in
the atmosphere. When the climate was warmer than in previous years, the concentration of this
gas, along with methane, increased as well, though science has not yet revealed if the amount of
carbon dioxide caused the elevated temperatures or vice versa. Yet, carbon dioxide remains the
culprit in many opinions. Its ability to trap heat close to the Earth’s surface due to its molecular
structure makes it a likely candidate. Especially since humans have been producing a larger
amount of it in the past couple of centuries. Beginning with the Industrial Revolution, the demand
for and use of energy has crescendoed with a growing population, which requires more land to be
stripped of vegetation for settling. This deforestation for commercial and other reasons has only
added to the amount of carbon dioxide that remains in the atmosphere, since plants play a key role
in reducing the natural and man-produced concentrations.
Carbon dioxide alone is not affecting the atmosphere. There are a number of other gases
also believed to play a role in Global Warming. Of these, scientists are concerned most with
methane, which acts like carbon dioxide, by absorbing infrared radiation that would normally be
radiated back into space, and keeping it closer to the Earth’s surface. Other Greenhouse Gases,
those gases that absorb radiation and heat included water vapor, nitrous oxide, halogenated
fluorocarbons (HCFCs), ozone, perflourinated carbons (PFCs), hydrofluorocabons (HFCs), and
sulfur hexafluoride (SF6). Some of these gases covet the incoming ultraviolet radiation from the
sun, while others work to trap what would normally be outgoing infrared radiation.
Yet another factor in the Global Warming hypothesis is the depletion of the Ozone. The
protective layer of this gas found in the stratosphere attacked by pollutants such as CFC’s, or
Freon, and depleted increases the amount of harmful ultraviolet rays the Earth receives from the
Sun. Raising the intake of heat the Earth is exposed to, coupled with the gases that trap in excess
energy could explain the warmer temperatures being experienced. This shows that the causes of
Global Warming may not be singular factors, but a coupling of reactions and interferences in the
atmosphere.
Although there still rests uncertainty about how Global Warming, assuming it exists,
will effect the Earth s climate and local weather, due to the complexities of its meteorological
system, scientists have proposed the following outcomes. First, with increased temperatures, the ice
at the polar caps may melt to a degree, increasing the water levels of the oceans. However, while
there will be an increase of oceanic water, there may be a decrease in surface water due to an
increased evaporation rate, which would lower the supply of inland freshwater in some regions.
Another consequence of higher evaporation rates is drier topsoil, which would effect crop yields as
well as increase the amount of natural and agricultural run off from hard rains. When it rains,
this drier soil would easily be washed away with the run off, decreasing the amount of nutrient
rich soil plants need and polluting streams and other bodies of surface water with suspended solids
and BOD. Some scientists also predict an increase in frequency and degree of rains in some areas
of the globe. These are just some possible effects of higher global temperatures. Aside from resulting
water pollution there may be adverse effects on the health of species residing on this planet.
Higher temperatures may be evidence of increased amounts of the Sun s energy not being reflected
back into space by clouds, meaning humans and other creatures are exposed to more of the
harmful UV rays emitted by the Sun. Yet with the limited ability to predict the Earth s turbulent
weather, the possible outcomes of continued Global Warming are numerous and some unknown.
While the debate on Global Warming rages on, there are actions humans can take to
prevent it from becoming a life threatening opponent, and if scientists decide it does not exist, at
least the world can benefit from our attempts. The majority of these precautions involve the
control of gas emissions such as carbon dioxide, methane, nitrous oxide, HFCs, PFCs, and SF6. For
example, prohibiting the open burning of solid wastes would reduce the amount of carbon dioxide
and methane that is released into the atmosphere. Reducing Global Warming is another incentive
for humans to develop alternative fuel sources and reduce the amount of fossil fuels processed and
consumed. A lower amount of these fuels burned would produce less greenhouse gasses, such as
methane and nitrous oxide. For gasses like HFCs, PFCs and SF6, which are produced by industries
and thought to be the most efficient in retaining heat, stricter emissions requirements would aid in
lowering their concentrations. Another way that could curb the rate of Global Warming is
something that most people could participate in, and that is simply preserving and planting more
vegetation. With the increased amount of carbon dioxide emitted into the air, it only makes sense
that to readjust the Earth s natural balance of production and consumption of this gas, there
should to be more plants to consume it.
As much as it would be an honor to put to rest the debate on Global Warming’s validity,
that is a task requiring extensive research, time and perhaps hindsight. The cause in changes in the
weather are less tangible than polluted water or land, due mainly to the complex design of the
Earth’s climate. However, if active measures are taken by humans to gain and emit more respect
for the world they inhabit, perhaps Global Warming will only be remembered as merely a past
concept.