Global Warming

1. TITLE. Global Warming: Environmental Damage or Natural Cycle

2. PURPOSE. The objective of this paper is to examine the history, indicators, causes and future concerns of global warming.

3. HYPOTHESIS. The Earth is experiencing more man-made pollution than at anytime in our recent past in spite of efforts to reduce emissions and the use of numerous chemicals. Additionally, we are experiencing numerous climatic changes from increased rainfall, temperature, hurricanes and melting of the polar ice fields to name but a few. Global warming is attributed to these climatic changes as a result of emissions from the use of fossil fuels and chemicals.

4. BACKGROUND. Starting with research in the late 1950s, scientists have recorded increased global temperatures and climatic conditions. Over the last twenty years, these climatic changes have been blamed on the build-up of pollution in the atmosphere or as it has come to be called- global warming. Global warming is attributed to the buildup of emissions of carbon dioxide, methane, nitrous oxide and other lesser gases. These gases prevent heat from escaping the EarthÐŽ¦s atmosphere creating the ÐŽ§green house effect.ЎЁ Recently, numerous weather changes and catastrophes are ascribed to global warming.

5. DATA.

a. History. The history of the Earth has been almost entirely dominated by ice ages with brief warming periods lasting between 15,000 to 20,000 years. Since the last Ice Age, the Earth has been warming for more than 18,000 years. The Earth did experience a ÐŽ§little ice ageЎЁ from about the 1400s to the middle 1800s. This was considered an anomaly. Without global warming we would not be able to inhabit the Earth. From the 1940s to the 1970s, Earth temperatures were declining in many places and many scientists feared, and some predicted, that we were entering another ice age. This was quickly reversed when in the 1980s and 1990s temperatures began to rise. Today, the general consensus among scientists and geologist is that human activities are speeding up the normal process of climatic change. Since the industrial revolution, the impact of human beings on the EarthÐŽ¦s atmosphere has multiplied exponentially. The use of fossil fuels, deforestation, increasing population and human activities has significantly contributed to climatic changes. Besides polluting the atmosphere, much of the topography in almost all geographical areas has been touched or contaminated by man in one way or another.

b. Definition. Global warming is the process of the Earth becoming hotter. The greenhouse effect is not a result of the warming of the Earth but a natural process the Earth uses to regulate its temperature. Water vapor, carbon dioxide and other trace

elements collect in the EarthÐŽ¦s lower atmosphere and trap heat that is re-radiated toward the Earth. Without this process, the surface temperature of the Earth would be 0„a F instead of the average temperature of 57„a F. Global warming is an increase of this effect due to the concentration of emissions in the atmosphere that trap more heat than would normally occur resulting in more heat being re-radiated to the Earths surface. This causes the EarthÐŽ¦s temperature to rise more than normal.

b. Indicators. There are many indicators that scientists and geologists believe demonstrate that global warming exists and its rate is directly attributed to human activities. These are a look at the main issues. There are numerous scientists that point to a greatly varied array of smaller inter-related signs of global warming.

Depending on the source, the consensus among scientists is that the Earth has warmed up between .6„a F to 1„a F over the last century with the increase over the last twenty years being in the neighborhood of .4„a F to .6„a F. This warming effect is not uniformly global. Some areas of the world have actually gotten cooler while others are heating up. This increase in temperature is the average Earth temperature for all global regions. These temperatures are recorded both on the ground and in the atmosphere. 2001 is claimed to be the warmest year on record and 1998 is the second warmest year since record keeping began in the 1860s.

Sea levels. Many scientists allege that the sea has been rising at a rate of 1mm to 2 mm per year over the last one hundred years. This rise is attributed to melting polar ice and runoff from increased rainfall in some areas of the world as a result of climatic change or global warming. This rise in sea level is threatening beaches and coastal populations living in low-lying areas.

Sea ice coverage. Utilizing satellite imagery, scientist estimate that Artic sea ice has diminished at a rate of 2% to 3% per decade. The Antarctic did not receive much attention until the 1970s. Some scientists, utilizing satellite images and measurements, contend that the some ice fields in Antarctica are actually growing as the ice recedes in the Artic.

Weather phenomenon. Much of the recent weather phenomenon and changes are attributed to global warming. El Nino in the Pacific is changing weather patterns in Central and South America. The recent record setting hurricane season is attributed to rising ocean temperatures, which fuel hurricanes, in the Atlantic Ocean. Finally, recent heat waves and flooding are also attributed to global warming.

c. Causes. Human activity contributed very little in the way of emissions to the atmosphere before the industrial revolution. Since the Industrial revolution man has contributed much more to our changing environment. The major contributors noted by scientist are carbon dioxide, methane gas,

The main greenhouse is carbon dioxide. Carbon dioxide emissions are the major man-made contributor, 40%, to global warming and pollution in general. Carbon dioxide is emitted from the burning of fossil fuels, waste, wood and wood products. Industry

Methane gas is emitted into the atmosphere in a variety of ways. The decomposition of refuse and livestock contribute methane gas to the atmosphere. Transporting fossil fuels such as oil, coal and natural gas release methane gas into the atmosphere. Methane gas is also contributed to the environment by agricultural activities as rice farming and cranberry bogs that release methane gas.

Nitrous oxide, also known as laughing gas, is produced in some industrial processes, vehicle emissions, agriculture and the burning of organic material. Nitrous oxide is also used as an anesthetic in the medical