I'm only half done, but I would appreciate your input.
When I was growing up, the weather seemed more predictable from year to year. Recently, it seems as if weather conditions have changed dramatically. The occurrence of nature disasters has increased and seasonal weather has become irregular. As these changes occur, I have become more curious about the highly publicized topic of global warming. There are two sides of global warming; is it manmade or is global warming an inevitable fact caused only by Mother Nature? This is the question I sought out before determining my own opinion. Through research, I have come to the conclusion that human activity is a substantial cause of global warming.
Global warming also known as "climate change" is the rapid increase in Earth's average surface temperature. Global warming occurs when levels of fossil-fuel gasses rise, limiting heat and light from escaping from the earth's atmosphere, which is called the greenhouse effect. Although it has been proven that temperatures fluctuate naturally, over the past 50 years the average global temperature has increased at the fastest rate in recorded history. NASA reported that the "meteorological year" spanning from December 2009 to November 2010 was the warmest in that agency's 131 years of record keeping.
Many greenhouse gases occur naturally, such as water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Others such as hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6) result exclusively from human industrial processes. Carbon dioxide is attributed as the leading cause of global warming. Although, is it a natural occurring gas it can also be induced by human activity. According to the Natural Resources Defense Council, Coal-burning power plants are the largest U.S. source of carbon dioxide pollution; they produce 2.5 billion tons every year. Automobiles, the second largest source, create nearly 1.5 billion tons of carbon dioxide annually.
(National Geographic 2010) "Humans have increased the amount of carbon dioxide in the atmosphere by more than a third since the industrial revolution." In addition, to the detrimental amount of carbon dioxide released into the atmosphere, scientists discovered that chemicals called chlorofluorocarbons (CFC's), long used as refrigerants and as aerosol spray propellants, damage the ozone layer. Destruction of the ozone layer is predicted to increase the incidence of skin cancer, damage crops and the marine food web, and to lead to an increase in carbon dioxide, possibly stimulating global warming by decreasing the number of absorbers; trees, plankton, etc.
The other gases responsible for global warming such as; methane, hydrofluorocarbons and dark soot particles make up 40% of the greenhouse gases emitted into the atmosphere. Methane is released from landfills and agriculture and has risen due to the population increase. (Ramanathan 2010) Methane alone is 25 times more powerful than carbon dioxide in causing warming. Hydrofluorocarbons used in air conditioning and refrigerants only account for a small percentage of greenhouse gases, but are expected to significantly increase over the next 50 years by 7 to 12 percent of what carbon dioxide contributes. Soot is not only the second leading cause of global warming, but also accounts for 1.9 million deaths annually. A study done by the NASA shows that cutting down the emission of soot can have instantaneous cooling effect.