Global Climate Change Essay, Research Paper
Global Climate Change
Climate change is not a new concept; in fact there is evidence of major climate changes throughout the earth’s history. However since the industrial revolution and especially since world war two, there has been an unprecedented change in the earth’s atmosphere (Gates 4). As of March 1999, scientists reported the construction of a thousand-year record of the average temperature on earth. The results of their study concluded that a nine hundred-year cooling trend has been decisively reversed within the last fifty years (Bell and Strieber 9-10). The effects of these rapid atmospheric changes are seen in increased storm intensity, rising seas, drier cropland, dying forests and coral reefs, proliferating diseases, floods, droughts, fires, and heat waves (Gates 2). These effects have hit home for many in the United States already with the intense flooding of the southeast coast that came with hurricane Opal in 1995 and the extensive flooding of the southeast Florida coast from hurricane Hugo in 1998 (Read 68). These storms are causing increasing amounts of damage due to their growing sizes. In June of 1999, a tornado struck the Midwest with record-breaking winds reaching up to three hundred and thirteen miles per hour (Bell and Strieber 126). #Also in 1999, hurricane Floyd set a record by reaching the size of Texas at its strongest point. Increasing numbers of forest fires spread throughout the southwestern regions of the United States every year. By June of 1998, after a great period of drought, giant fires in Texas together with fires in Mexico and Guatemala created a cloud of smoke thousands of miles long and thick enough to block the suns light at noon in the worst places. This was the second worst fire outbreak ever recorded in human history (Bell and Strieber). It is clear that our temperatures are rising around the globe, but by how much, and how fast?
The Size of the Problem
While some scientists disagree about the cause or rate at which the earth is warming, scientific research leads us to believe that the temperature rise is real (Verma 125-127). The global average temperature is predicted to rise somewhere between 1 and 3.5 Celsius degrees by 2100, according to the rate of carbon emissions and other greenhouse gasses that continue to be emitted (Flavin and Dunn 6). In 1998 the global average temperature exceeded even the most radical global warming models whose predictions were as recent as 1995. 1998 ended up as the warmest year recorded in history until 1999, when it became clear that temperatures were rising much faster than ever expected (Bell and Streiber).
Contrary to popular belief the greenhouse effect is not a bad thing. It is completely natural and it is in fact vital to our survival on earth. Without the greenhouse effect, the world would actually be about 33 degrees Celsius colder (Read 28). In recent years however, we have been experiencing too much of a good thing. Greenhouse gasses prevent the suns heat from escaping the earth’s atmosphere after it enters, making the temperature rise. We base our global warming models on the amount of carbon dioxide and other greenhouse gasses humankind is releasing into the air (Bell and Strieber 197). The acceleration of global warming can be linked to an increase in industry, forest destruction, and agriculture, which are major producers of greenhouse gasses such as carbon dioxide and methane (Gates 1).
In the last 160,000 years before the industrial revolution the concentration of carbon dioxide, the most prevalent of the greenhouse gasses in the atmosphere, never exceeded about 280 parts per million. Since then, carbon dioxide has risen to about 360 parts per million and continues to rise (Read 39-40). The major cause of the increase in carbon dioxide in the atmosphere is the burning of fossil fuels like, coal and petroleum (Budyko 185-186).
Methane, another greenhouse gas, is 70 times more effective at trapping heat than carbon dioxide. Methane is increasing by about 1% every year, which is twice as fast as carbon dioxide. However, methane levels in our atmosphere are much lower than carbon dioxide levels. Some major sources of methane include the anaerobic decomposition of organic material such as cattle manure and rice paddies; the extraction, refining, and distribution of oil and gas; cement manufacturing; and coal mining (Gates 13-14).
Nitrous oxide, while only increasing at a rate of 0.2% a year, is 200 times more effective at trapping heat than carbon dioxide. The increase in nitrous oxide, however small it is, is attributed to the increasing use of fertilizers and the high combustion temperatures in fossil fuel burning power plants (Gates 15). Other greenhouse gasses have a similar effect in the atmosphere like ozone and chlorofluorocarbons, but are found in even less significant amounts.
Impacts on the Environment
These trends of global warming are predicted to have an extensive impact on the ecosystems of the world. The warming ocean currents, the decline in forests and the effects on animals, agriculture and insects will be significant. The effects of global warming and the warming seas can already be seen among coral reef populations. In the early 1980’s a significant rise the temperature of the Pacific Ocean led to extensive bleaching of coral populations along the Great Barrier Reef (Warrick 11-13). Bleaching is when the coral turns white, a result of the disappearance of the algae that the coral feed on (Bright 29-30). This in turn had a negative effect on fish populations, which feed on the coral and are a major source of food for the human population of the world. The warming seas have a similar affect on fisheries around the world. In tropical regions such as Hawaii, the heat content of the upper layers of the ocean may be directly determined by from sea levels. Lower sea levels indicate that the warm surface layer is relatively thin and that the cooler, nutrient rich water is closer to the surface increasing fisheries stocks (Warrick 65).
Forests cover between 35 and 40% of earth’s land area. They create habitat for wildlife, protect against erosion and store over 80% of the world’s organic carbon (Gates 109). The increase of weather disturbance and habitat change due to global warming will have a negative effect on forest growth. Destruction from increased storminess and fire is part of the forests natural evolution, but too many disturbances along with drought, insects, and disease will hinder reproduction (Godish 198). Forests have always dealt with climate change through migration, but in today’s world migration will be more difficult than ever due to the acceleration of change and the disruption of the landscape including cities and highways (Gates 110).
Animals will also be affected by the changes in our atmosphere. In 1998, levels of ozone in the upper atmosphere became alarmingly depleted due to the continued release of greenhouse gasses into the atmosphere. This thinning of the ozone layer has had serious effects among animals. Overexposure to ultraviolet radiation reduces the ability of animals to ward off disease. In recent years, there has been a significant increase in sickness among wild species and herd animals around the world (Bell and Strieber 128). Many bird species depend entirely on a specific habitat that might no longer exist if temperatures continue to rise. Shorebirds depend on aquatic food sources that will not be as prevalent if water temperatures continue to rise (Gates 169). Species of nesting birds that depend on vegetation, as their source of protection from the elements will no longer have a place to live if the climate becomes intolerable for certain plant species (Gates 173). Many birds feed on insects that live in the ground, insects that will not be able to survive if deforestation occurs and the chemical components in the soil change (Gates170-173).
Climate changes are affecting agriculture as well. Human beings are ever so dependent on agriculture as our main food supply. As our population increases the demand for food increases. Thus forests are cut down to make room for agriculture and cattle ranching (Read 244). More land is now cleared and turned into agricultural land, which is then overworked and abandoned, impoverishing more ecosystems. Open soil is left to erode away and land is overused for agriculture depleting the remaining soil of important nutrients (Gates 240 – 241). The use of fertilizers, pesticides and irrigation adds to the greenhouse gasses released into the environment making the situation even worse. Meanwhile, the climate is changing faster than crops can adapt to the new conditions (Gates 202-204).
The new warmer climate will also present another problem for plants and animals alike. Warmer winter temperatures will allow insect pests to stay alive longer; increasing reproduction rates (Gates 232-234). These increased numbers of insects will be able to destroy more croplands causing a food shortage for our growing population and will also carry with them life threatening diseases across their increased habitats (Gates 234-238).
The Economy
If the world’s economy is to survive a major climate change, many aspects of life must change. In order for our economy to cope with the warming trend of the world we must slow it down as much as possible. This means making a transition from a fossil fuel energy based economy to a renewable energy based economy. No longer can we continue to waste our valuable natural resources. We must become an energy efficient society. By taking advantage of alternate sources of power like solar, hydroelectric, and wind power and changing the way we live, we can make a difference. This necessary transition will not be easy, but it will be as dramatic as the industrial revolution that escalated the problems in the first place (Flavin and Dunn 18-25).
Solar Power is the fastest growing energy source used today. In 1975 solar energy cost seventy dollars per watt, but by 1997 it only cost about four dollars per watt comparatively (Bell and Strieber 202). If we could use this solar power instead of internal combustion engines and coal burning power plants we could significantly decrease the amounts of carbon released into the atmosphere. Fossil fuels account for ninety percent of the world’s commercial energy production; with coal producing more carbon dioxide per unit of energy than any other fuel (Elsom 353-354).
Wind power can also be used as an alternative to fossil fuels. In 1998 wind power only cost eight hundred dollars per kilowatt, as opposed to twenty-six hundred dollars per kilowatt in 1981 (Bell and Strieber 202). The expense of alternative energy sources is decreasing, as research continues, however, it is not yet cost efficient for us to rely on any of these methods. Until alternative energy sources become a more realistic solution for our problem, we will have to focus on methods of minimizing carbon emissions (Gates 250).
There are many ways to reduce the release of emissions from fossil fuels. The use of natural gas instead of coal or oil reduces emissions significantly (Verma 130). There are also emission-controlling devices found on automobiles as well as power plants. The catalytic converter helps reduce emissions from automobiles, while chemical processes help reduce emissions from power plants (Gates 250). These methods however are not cost effective or energy efficient. The burning of fossil fuels will always cause pollution. So then it is up to us as individuals to help each other make the transition away from our dependence on fossil fuels. By using public transportation and conserving energy, with the incentive of environmentally friendly legislation like gas taxes and parking fees, we can start to fix our accelerated rate of warming and global instability (Lowe 34-35).
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