the many causes of global warming, human activity, carbon dioxide, and greenhouse gasses will be talked about. According to “WWF-Canada” (2007), human activity has the biggest impact on global warming. When humans burn fossil fuels to generate electricity and power vehicles, they produce the gases that cause global warming. The more they burn, the faster churns the engine of global climate change (“Natural Resources Defense Council”, 2007). “WWF-Canada” (2007) says that humans that pollute heat in the atmosphere are causing changes to the global climate. They say that it has driven the average global temperature up by 0.7° Celsius (C) since the Industrial Revolution.
Carbon dioxide, one of the biggest contributors of global warming, is released when fossil fuels, such as oil and coal, are burned for energy (“Natural Resources Defense Council”, 2003). A layer of carbon dioxide traps heat in the atmosphere (“Natural Resources Defense Council”, 2003). According to the “Natural Resources Defense Council” (2003), a car that gets 20 miles per gallon will emit about 50 tons of carbon dioxide over its lifetime. The “Causes of Global Warming” article in Wikipedia (2007) states that the atmospheric concentrations of carbon dioxide and methane have increased by 31% and 149% respectively above pre-industrial levels since 1750. It also states that the increased carbon dioxide in the atmosphere warms the Earth's surface and leads to melting of ice near the poles. Burroughs (1996) says that adding carbon dioxide to the atmosphere will warm the earth.
The greenhouse effect, first discovered by Joseph Fourier in 1824, and first investigated quantitatively by Svante Arrhenius in 1896, is the process in which the emission of infrared radiation by atmospheric gasses warms a planet's surface. (“Causes of Global Warming”, 2007). “Causes of Global Warming” (2007) states that greenhouse gas effects are the main cause of global warming. Many sources conclude that the main causes of global warming are human activity, carbon dioxide, and greenhouse gasses