Реферат: Global Warming Essay Research Paper

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.