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Global Warming Extended Definition Essay Essay, Research Paper

Global Warming Extended Definition Essay

The importance of the stratospheric ozone layer, which filters out most of the sun’s harmful ultraviolet radiation, in protecting the Earth’s surface from the harmful effects of solar ultraviolet radiation has been recognized for many decades. It was not until the early 1970s, however, that scientists began to actually grasp the fact that even relatively small decreases in the stratospheric ozone concentration can have a serious impact on human health–an increased occurrence of skin cancer, particularly in fair-skinned people. The process that causes this decrease in the stratospheric ozone is referred to as global warming. The most definite cause of this process has not been determined, yet scientists are aware of its reality and harm to humans. Many scientists believe global warming is caused by the increase of carbon dioxide in the Earth’s atmosphere, while other scientists believe that the health threat caused by global warming is due to an unusual interaction between cosmic rays and clouds as well as other natural occurring events.

The National Weather Service announced that 1998 was the warmest year (on record on average, around the world). A recent tree-ring study indicated that this is the warmest decade in six hundred years (Allen & Herreid, 82). Undeniably, the weather is getting warmer. According to an article in The Economist, a conservative newsmagazine,

“The sea is warming, the plankton dying; floods are sweeping the land. In California, the climate is acting in a peculiar way. So, too, in Antarctica, where unlooked-for flowers are blooming as the ice shelves disintegrate In Southern Africa, it looks as though the rains will fail. Again. All over the world, there is something odd about the weather” (”Feuding over Global Warming”, 6).

There may be nothing out of the ordinary about these latest extremes in the weather, but they may all be part of a climatic conspiracy.

The people who believe in this climatic conspiracy believe that the greenhouse gases, especially carbon dioxide, pumped into the atmosphere by humans are warming the globe and changing the Earth’s climate. They believe that global warming is occurring because, “these gases [greenhouse gases, especially carbon dioxide] are transparent to sunlight, which warms the Earth, but absorb infrared radiation, by which the Earth radiates heat out into space” (Kay, 5). This suggests that humans along with carbon dioxide are responsible for the global warming and the outrageous weather occurrences in process. Excessive carbon dioxide from automobiles, causing the ozone layer to be depleted, is one explanation for what is causing global warming. Many scientists and world leaders believe carbon dioxide is the culprit to this alarming dilemma, while others do not support this theory at all.

Taking the opposite view, some scientists and politicians believe that global warming may be less humanity’s fault than the sun’s fault.

“The Earth’s climate fluctuates in a ten to twelve year cycle, in parallel with the rise and fall of the number of sunspots-transient dark patches on the face of the sun the current rise in the earth’s temperature owes more to a bigger, longer-term change in the sun’s output-an increase in the average number of sunspots measured over the course of a cycle-and less to the greenhouse gases ” (”In flux: a strange interaction”, 66).

Sunspots, created by twisted magnetic fields on the face of the sun, determine the sun’s brightness. The surface magnetism on the sun and its brightness runs on an 11-year variation. The sun dims during a magnetically low period and brightens during a magnetically high period. These changes in brightness are very slight yet some scientists believe that they are enough to change global temperatures (”Mysteries of nature”, 10).

The scientists who believe that the sun is responsible for global warming also believe that along with the changes of the sun, other naturally occurring and unstoppable events influence global temperatures. One of these events, El Nino, arrives every two to seven years when a build-up of warm water from the western Pacific mysteriously moves off of the western coast of South America, triggering weather patterns that allow the waters to increase in temperature (”Mysteries of nature, 10). This movement of warm water northwest affects or alters the climate by partially relocating the typical jet stream of moisture further north. The relocation of the jet stream causes many areas to be warmer and dryer than normal. El Nino episodes as well as other cyclonic storms have been increasing in frequency and intensity recently, thus, some believe, upsetting the global weather and increasing global warming. As many believe, the combination of the sun spots theory and the naturally occurring weather phenomena could account for the global warming we are experiencing.

Global warming could be caused by the reduction in the ozone layer due to high levels of carbon dioxide in the atmosphere. Global warming could also be caused by the change in magnetic fields on the face of the sun, creating sun spot variation, in combination in weather phenomena such as El Nino. There could even been other as yet undetected reasons of global warming. Scientists continue to theorize on a daily basis for what could be causing the phenomenon, in their search for a solution. After my investigation of this issue, and upon examining many related documents, trials, hypothesis, etc., I support the view of those that believe carbon dioxide from more and more vehicles, and the associated reduction of the ozone layer, is the main cause for global warming. My position is supported by the majority of those in the scientific field and by most of the

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