Humanity and Global Warming - Essay Example

Evidence indicates humanity's direct impact on this trend in the latter half of this century, according to the 2001 report by the Intergovernmental Panel on Climate Change, who base this claim on meteorological and oceanographic models. When these models - which are projected from geologic evidence of the Earth's natural history of climate change - are compared with the reality of today's climate, the difference bears a direct correlation to human output of carbon dioxide. The fossil fuels humans burn through transportation, household heating, and as a power source in general emit carbon dioxide, which in turn accumulate in the upper atmosphere and serve as a blanket by retaining solar heat.

Atmospheric carbon dioxide levels are currently at their highest peak in the last 650,000 years (Fitzpatrick). This blanketing action is commonly referred to as the "Greenhouse effect" and is a naturally occurring phenomenon. Solar energy creates both the weather and climate, as well as warming the surface. The planet in turn reflects this heat back into outer space. The collection of water vapor, carbon dioxide, and other gases in the atmosphere act like window panes on a green house, allowing the energy to enter, but then retaining a significant portion of the energy which allows the planet to remain at a comfortable average of 60F.

The natural emission of greenhouse gases by humans has historically been counterbalanced by plant respiration and organic decomposition at a ratio of 10:1. Since the industrial revolution, however, human output of carbon dioxide, methane, and nitrous oxide have all grown exponentially. Compounding the problem of rising greenhouse gases, increased farming production, mining, industrial pollution, and landfills have resulted in massive deforestation, thereby significantly decreasing the method by which carbon dioxide is converted back into oxygen ("Climate").

Scientists have suspected a connection between human activity and global warming since the early 1920's, yet little conclusive evidence has been observable until the 1970's, when people grew concerned that the drought in the African Sahel was slowly being encroached by the Sahara. In 1975, Jule Charney (a climate modeler) proposed that the Sahel land, which had been largely cleared of vegetation for various reasons, now contained a large amount of exposed clay, which reflected a greater amount of heat, thereby effecting the wind and rain patterns of the region.

By 1988, scientists had gathered enough evidence to confirm that cleared land not only warms more than forested land, but the rise in temperature makes it all the more difficult for vegetation to return. Human activity can therefore effect the climate through small changes to an environment's balance, which sets off a progression of effects that alter the environment completely (Weart, "Biosphere"). Today, there are numerous signs of global warming: warming ocean water is altering wind patterns (which combined with the evidence of cleared land warming results in massive droughts), since the melting polar ice masses shift precipitation further away from traditional regions ("Current Science").

Natural weather disasters have increased in