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Global Warming

Global Warming is an international phenomenon where the weather and temperature change unpredictably and fast (when greenhouse gases get trapped in the atmosphere). Since the Industrial Revolution, global warming has increased, affecting Earth by rising its global temperature (which has increased due to the fact that the amount of carbon dioxide and other gases spewing from industrial plants has enlarged). Nevertheless, to understand global warming, one must understand the components intertwined with its occurrence (such as carbon dioxide, greenhouse gases, Ozone O_3, Chlorofluorocarbon, and CFCs gases). In addition, one must learn where, why, and how global warming occurs.

To begin, one must first know the difference between the terms, weather and climate. Despite the fact that they are related, weather and climate are two distinct things. Weather refers to the atmosphere’s current condition at a specific location on Earth. Weather conditions typically change hourly and refer to a small area. The factors that are included in weather measurements are air temperature, wind speed and its direction, humidity, precipitation, and cloud locations. Although climate does include some of these factors, climate is a measurement of the average weather condition of a large region for a long period of time. Furthermore, climate is measured in decades.

Greenhouses gases are another important component of global warming. As everyone knows, the Earth’s atmosphere consists of various different chemical compounds. Among these compounds, there are gases (called greenhouse gases) in our environment that are primarily generated by fossil fuel consumption. Greenhouse gases are vapors that are trapped in the Earth’s atmosphere; they absorb and emit radiation at the rate of thermal infrared. The primary greenhouse gases in Earth’s atmosphere are carbon dioxide, water vapor, ozone, methane, and nitrous oxide.

Carbon dioxide (CO₂) makes up about eighty percent of primary greenhouse gases. It is a chemical compound, in the state of gas, with a natural, or anthropogenic (caused by human activity), origin. Also having a natural origin, CO₂ is emitted by volcanoes, geysers, oceans, lakes, aerobic organisms (through respiration), organic materials (from their decay), land animals (as they exhale, while breathing), and humans (from their breath). In addition, carbon dioxide can be found, naturally, in oil and gas deposits. Regarding its anthropogenic origin, carbon dioxide can also derive from the combustion of fossil fuels (such as gas motor vehicles, fabrics, and manufactures). Furthermore, carbon dioxide can be generated from coal, which is rich in carbon when burned.

Carbon dioxide is essential to human life due to the fact that it, as a major greenhouse gas, maintains an average temperature, on Earth, of 59° Fahrenheit (Gore, 2007). Without these gases, the Earth’s surface temperature would drop to around 0° Fahrenheit (Gore, 2007). However, the problem is that an excess of CO2 gases contributes to global warming. There are various researches that suggest that there is a direct correlation between carbon dioxide and temperature. In other words, the more concentrated the CO₂ (ppm) in Earth’s atmosphere gets, the higher Earth’s temperature is going to get. Humans cannot stop these gases from naturally occurring, but they can prevent the anthropogenic ones. Consequently, many experts advise people to prevent or reduce the emission of CO₂ gases into Earth’s atmosphere. Some ways to prevent the emission of CO₂ gases are regulating the emission of pollution, promoting the manufacturer, using electrical or hybrid motor vehicles, and preventing the destruction of forests (which absorb CO₂ to form oxygen).

Another significant compound in global warming is chlorofluorocarbon (also known as CFCs, or Freon). chlorofluorocarbon is an organic compound that contains carbon, chlorine, and fluorine. This compound is produced as a derivative of propane, methane, and ethane, and is used as a refrigerant, solvent and propellant. Moreover, it has a lifetime of 20 to 100 years.

CFCs gases are extremely stable, do not dissolve because of rain, and stay in Earth’s atmosphere for about two years (which is the time it takes them to reach the stratosphere). In the stratosphere, ultraviolet rays hit CFCs molecules (CFCl₃) to form chlorine atoms (Cl), which then react with ozone molecules (O₃) to form chlorine monoxide (ClO) and oxygen molecules (O₂). Later, the free oxygen molecules react with the chlorine monoxides to form chlorine atoms, which are then free to start the process all over again (which slowly destroys ozone molecules). It is known that one CFC molecule can destroy up to 100,000 ozone molecules.

Ozone O₃ (μ-O) plays a major role in global warming. Ozone O₃ is an inorganic molecule (in its gas state) that forms in the Earth’s atmosphere through photolysis. (Photolysis is a process in which O₂ molecules split apart, due to ultraviolet rays, to form individual O molecules, which join together to form O₃ molecules, or the ozone.) The formation and destruction of the ozone is steady, with a relative constant concentration and altitude of 10 to 19 miles from Earth’s surface.

The ozone layer plays an important role in the warming of the Earth due to the fact that it is meant to prevent the Earth from warming up too much. The Sun’s irradiated rays penetrate Earth’s lower atmosphere and warms its (Earth’s) surface. However, these sunrays are filtered by the ozone layer, which is located in Earth’s stratosphere. The ozone layer protects Earth from ultraviolet rays by reducing the intensity and preventing very high temperatures (which could potentially destroy every animal and human by melting every thing) to occur on Earth.

In regard to the relationship between CO₂ and the ozone layer, CO₂ does not directly affect the ozone layer. What actually occurs is that the ozone’s generation is very slow and gases, such as water vapor and CO₂, stay in the atmosphere semi permanently, without physically or chemically changing. Then, when the sun’s rays (ultraviolet rays) are emitted, they pass through the atmosphere, warming the Earth. Nevertheless, this heat cannot leave the Earth because the gases block Earth’s heat from escaping, which makes, consequently, what is known as global warming.

The region most affected by global warming, where the climate changes constantly, is the Arctic due to the fact that it is located on a highly sensitive part of Earth. Furthermore, the Arctic region is very thin and suffers from ruptures and melted ice, which destroy the habitat of different animals, such as polar bears. In addition, global warming also affects the native people, plants, and wildlife.

One noticeable victim of global warming is The Muir Glacier, located in the Glacier Bay National Park and Preserve, in Alaska. As shown on the left in figure 1 (on the following page), which was taken in August 1941, the glacier once covered the entire ocean between the mountains. Nowadays, as shown on the right in figure 1 (below), which was taken in August 2004, the glacier is barely visible due to the fact that global warming has made most of the ice melt, causing the glacier to shorten by more than 31 miles and thin by more than one kilometer (U.S. Geological Survey, 2014).

Figure 1: Muir Glacier

To make matters worst, glaciers, such as the Muir Glacier (melting glaciers), contribute to the rising sea levels, which produces coastal flooding and contaminates fresh water supplies. Snow and ice generally act like a security system by cooling the Earth’s layer over the Arctic. Thus, when the ice and snow that covers the Earth melts, the earth absorbs more sunlight and gets hotter.

So, is global warming a big issue to consider? As one can see, it is a huge issue. Global warming affects the planet’s temperature, climate change, and is one of the leading problems that face our world today. Carbon dioxide and other greenhouse gases are heating up the atmosphere and are, thus, jeopardizing every day life. This problem is caused by the release of principal human-made greenhouse gases into Earth’s atmosphere. Therefore, humans can prevent global warming through the prevention, replacement, and reduction of CFCs on Earth. Furthermore, by doing these things, humans can save the environment and, in a way, the world!

Resources

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Climate Central, Inc. Global Weirdness: Severe Storms, Deadly Heat Waves, Relentless Drought, Rising Seas, and The Weather of The Future; Pantheon Books: New York, 2012.

Goodall, C. Ten Technologies to Save the Planet; Greystone Books: Vancouver, 2010.

Gore, A. An Inconvenient Truth: The Crisis of Global Warming; Viking: New York, 2007.

Haugen, D. M. & Musser, S. Is Global Warming a Threat?; Greenhaven Press: Detroit, 2007.

Haugen D., Musser S., & Lovelace, K. Global Warming; Greenhaven Press: Detroit, 2010.

Joesten, M. & Hogg, J. L. CHEM In Your World; Brooks/Cole Cengage Learning: Belmont, 2011.

McKibben, B. The Global Warming Reader: A Century of Writing About Climate Change; Penguin Books: New York, 2012.

U.S. Geological Survey. Glacier and Landscape Change in Response to Changing Climate. http://www.usgs.gov/climate_landuse/glaciers/repeat_photography.asp (accessed June 23, 2014).

Weart, S. R. The Discovery of Global Warming; Harvard University Press: Cambridge, 2003.