Term paper on Global Warming

Free Global Warming papers

Jerry Garcia
Alex Walker Jerry Garcia and the Grateful Dead Rock Legends of the 60s and 70s Walker 2 Jerry Garcia s life was filled with wonderful things, many of which he never expected in the first place. After an almost fatal heroin overdose in 1986, Garcia philosophically stated, I m 45 years old, I

Zpd: Implications For Teaching
THE ZONE OF PROXIMAL DEVELOPMENT AND ITS IMPLICATIONS FOR LEARNING AND TEACHING There can be little doubt that, in the English-speaking world at least, it is the "zone of proximal development" that has been Vygotsky's most important legacy to education. Indeed, it is the only aspect of Vygotsky's

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Jeffery D. Dwyer

The causes and effects of Global Warming.

Like many pioneer fields of study, there are uncertainties associated with the science of global warming. This does not imply that all things are equally uncertain. Some aspects of the science are based on well-known physical laws and documented trends, while other aspects range from 'near certainty' to 'big unknowns'.

Scientists know for certain that human activities are changing the composition of Earth's atmosphere. Increasing levels of greenhouse gases, like carbon dioxide (CO2), in the atmosphere since pre-industrial times have been well documented. There is no doubt this atmospheric buildup of carbon dioxide and other greenhouse gases is largely the result of human activities.

It's well accepted by scientists that greenhouse gases trap heat in the Earth's atmosphere and tend to warm the planet. By increasing the levels of greenhouse gases in the atmosphere, human activities are strengthening Earth's natural greenhouse effect. The key greenhouse gases emitted by human activities remain in the atmosphere for periods ranging from decades to centuries.

A warming trend of about 1.F has been recorded since the late 19th century. Warming has occurred in both the northern and southern hemispheres, and over the oceans. Confirmation of 20th-century global warming is further substantiated by melting glaciers,

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decreased snow cover in the northern hemisphere and even warming below ground.

Figuring out to what extent the human-induced accumulation of greenhouse gases since pre-industrial times is responsible for the global warming trend is not easy. This is because other factors, both natural and human, affect our planet's temperature. Scientific understanding of these other factors most notably natural climatic variations, changes in the sun's energy, and the cooling effects of pollutant aerosols remains incomplete.

Nevertheless, the "Intergovernmental Panel on Climate Change" (IPCC) stated there was a "discernable" human influence on climate; and that the observed warming trend is "unlikely to be entirely natural in origin." IPCC also wrote, "Our ability to quantify the human influence on global climate is currently limited because the expected signal is still emerging from the noise of natural variability..." (572)

In short, scientists think rising levels of greenhouse gases in the atmosphere are contributing to global warming, as would be expected; but to what extent is difficult to determine at the present time.

As atmospheric levels of greenhouse gases continue to rise, scientists estimate average global temperatures will continue to rise as a result. By how much and how fast remain uncertain. IPCC projects further global warming of 2-6.F by the year 2100. This range is primarily the result of uncertainties in the response of global climate to the buildup in greenhouse gases, as well as future greenhouse gas emission trends.

The IPCC states that even the low end of this warming projection "would probably be greater than any seen in the last 10,000 years, but the actual annual to decadal changes would include considerable natural variability." (www.epa.gov/globalwarming)

Scientists have identified that our health, agriculture, water resources, forests, wildlife

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and coastal areas are vulnerable to the changes that global warming may bring. But projecting what the exact impacts will be over the 21st century remains very difficult. This is especially true when one asks how a local region will be affected.

Scientists are more confident about their projections for large-scale areas (e.g., global temperature and precipitation change, average sea level rise) and less confident about the ones for small-scale areas (e.g., local temperature and precipitation changes, altered weather patterns, soil moisture changes). This is largely because the computer models used to forecast global climate change are still ill-equipped to simulate how things may change at smaller scales.

Some of the largest uncertainties are associated with events that pose the greatest risk to human societies. IPCC cautions, "Complex systems, such as the climate system, can respond in non-linear ways and produce surprises." (www.epa.gov/globalwarming) There is the possibility that a warmer world could lead to more frequent and intense storms, including hurricanes. Preliminary evidence suggests that, once hurricanes do form, they will be stronger if the oceans are warmer due to global warming. However, the jury is...