Global Warming: Soaking up too much Sun
|
Even before Homo erectus first stood up on his hind legs, humans have had an enormous influence over the environment and atmosphere. They have used land, oceans, and other natural resources to help further their expansion and growth. Unfortunately, while the human race flourished, the atmosphere and environment did not. Humans released toxins into the air with their large-scale fires and killed many species to extinction. However, global warming is one of the largest and most current dilemmas the Earth is facing. Over the past century, the temperature of the Earth’s surface has risen 1° C and in the past fifty years, humans have been the primary cause of the warming of our planet.
One of the major confusions in environmental issues today is the concept of the “greenhouse effect”. People identify this term in a very negative fashion when in fact the greenhouse effect is what keeps Earth’s temperature livable for organisms such as humans. Energy from the sun heats up Earth’s surface and in turn the Earth radiates some of that heat back into space. The purpose of the atmosphere is to trap some of the “greenhouse gases” and energy in order to keep temperatures similar to what they are today as well as protect from extreme temperatures. However, complications arise when the concentration of the greenhouse gases increase. Before the Industrial revolution, human activities did not have such a drastic effect on the atmosphere. Yet, as the population of humans on Earth grew, more gases began to be emitted into the atmosphere where they accumulated and remained.
One of the most detrimental gases to the atmosphere, carbon dioxide, is accumulating at an alarmingly fast rate. Currently, about half of the carbon dioxide released is absorbed by the oceans or by photosynthesis, the rest builds up in the atmosphere where it stays for decades. This build up resulted in an increase in carbon dioxide concentration from 275 parts per million before the industrial revolution to 310 ppm in 1958 to 368 ppm in 1999. Methane is another chemical that is accumulating in the Earth’s atmosphere. Two-thirds of current emissions result from cattle farming, rice paddies, landfills, coal mining, and oil and gas production while one-third comes from natural resources such as wetlands and termites. Other gases that are currently collecting in the atmosphere are nitrous oxide (laughing gas), ozone, chlorofluorocarbons, hydrofluorocarbons, perfluorocarbons, hydrochlorofluorocarbons, and sulfur hexafluoride. While carbon dioxide, methane, and other greenhouse gases stay in the atmosphere for decades, precipitation removes the majority of the sulfates from the atmosphere within three weeks.
A planet’s temperature change is an evolutionary mechanism that is dependent on three different factors. First, the amount of sunlight received determines how much energy is available for Earth’s disposal. Over the last two million years, ice ages and global heating came about because of changes in the amount and timing of sunlight. Second, there is a portion of energy that is lost or reflected back into the universe. The last factor is the extent at which the atmosphere retains heat. During the twentieth and twenty-first centuries there has been a drastic increase in the concentrations of organic water vapor and carbon dioxide on the Earth’s surface. This naturally occurring “greenhouse effect” has increased the temperature at the Earth’s surface and without it the Earth would be sixty degrees colder.
The industrial revolution can be considered a turning point in the atmospheric condition of the Earth. While there was a slight increase in greenhouse gases before this massive upsurge of industry, the atmosphere was still in a relatively balanced state. After the industrial revolution, the carbon dioxide concentration increased by 30 %, methane concentration doubled, and the nitrous oxide concentration increased by 15 %. Currently, fossil fuels are burned to run cars and trucks as well as heat homes and businesses. Over the past century there has been a major increase in agriculture, deforestation, number of landfills, industrial production, and mining. Power factories now account for 98 % of the United States carbon dioxide emissions, 24 % of methane emissions, and 18 % of nitrous oxide emissions. Individually in the U.S., approximately 6.6 tons of greenhouse gasses are emitted per person every year. Emissions per person have risen by 3.4 % between 1990 and 1997 in the United States alone, but there are similar statistics for many other countries. In 1997, the United States was responsible for one-fifth of the total greenhouse gases in the world.
The overwhelming impact of global warming has already taken effect and will continue to do so if no action is taken to correct it. The collection of greenhouse gases will cause extreme temperatures which would lead to a major loss of human life. The number of people who die on a certain day increases drastically as temperature increases to the extremes and causes massive heat exhaustion. People with heart problems are particularly at risk because their cardiovascular system has to work overtime to cool their bodies down. The rising concentration of ozone causes lung damage, chest pains, nausea, and pneumonia. Warmer temperatures also create a breeding ground for serious diseases that are transferred through mosquitoes and other insects. These insects are more prevalent in warmer temperatures; therefore, they can be vectors for diseases such as malaria.
Global warming has always been a personal interest of mine mainly because it is a problem that the human race can control. We unknowingly caused this massive destruction of the Earth and now we need put a great deal of effort into fixing the atmosphere to protect, not only humans, but all other living creatures. Educating the public about the causes and effects of global warming is a step that many countries, states, and cities have taken. One local example is the “Walk! Philadelphia” campaign which encourages people to walk or use public transportation to reduce the use of cars. Currently, international and government agencies are thinking of ways to monitor and reduce the amount of greenhouse gases released into the air. I am optimistic that our government and governments from all over the world are working hard to overcome the causes and effects of global warming. While any large-scale change will be gradual, there is no doubt in my mind that we will fix the atmospheric problems to the best of our ability.
-------------
* All the information in this paper came from the Environmental Protection Agency’s Global Warming website at:
http://yosemite.epa.gov/oar/globalwarming.nsf/content/index.html
|