Introduction
The history of human evolution is intriguing. From invention of fire to industrial revolution and globalisation, man has come a long way. Every effort has been/is being made to improve quality of human life. However, in the process of making his life comfortable, man’s influence on nature has been increasing. Rising pollution, climatic changes and global warming have become the key environmental concerns today. Have these issues been triggered by man’s increasing efforts to control his environment? Are these efforts causing global warming and climate changes occurring today? The objective of this paper is to contemplate on the issues of environmental changes and global warming raised here that are debated to be real and man-made.
The paper is divided into three sections. The first section defines global warming and what is constitutes of. The second section is on the author’s thoughts and perspective on global warming. The author’s opinion is that global warming is real and a serious concern for human existence on this earth. The third section concludes the paper. At the end of the paper, the author intends to put across her stand towards global warming. The argument will be supplemented by references from other sources relevant to this discussion.
Definition of Global Warming
According to American Policy Roundtable (n.pag.), global warming is a hypothesis that earth’s atmosphere is warming because of the release of greenhouse gases like methane, carbon dioxide, carbon monoxide, nitrous oxide etc. These gases are important for survival of life on earth as it helps keep earth warm and facilitates lives on it. They prevent the earth from getting too cold. But when the concentration of these gases rises in atmosphere, it warms the earth more than comfortable limits. This process of warming of earth is known as global warming.
The history of global warming dates back to the 19th century. The hypothesis was originated in 1896 when Svante Arrhenius, a Swedish chemist, developed the theory that carbon dioxide emissions from the burning of fossil fuels would cause global temperatures to raise by trapping excess heat in the earth’s atmosphere (eNotes, n.pag.).
The process of earth’s warming due to greenhouse gases is known as greenhouse effect. The rays of the sun falls on the surface of the earth, warms its surface and radiates the energy back from earth. The greenhouse gases reflect a portion of this energy back to earth warming it further. When composition of these gases increase in atmosphere, it absorbs and reflects back energy to earth even more, making it warmer.
I believe that the hypothesis of global warming is true. The opinion is based on the argument that the rise in level of greenhouse gases is the key reason behind global warming. Increase in level of greenhouse gases is the reasons debated for causing global warming. Studies have found that concentration of greenhouse gases in the atmosphere has significantly increased over the years. There are various researches that support this argument. A research found that concentration of CO2 in the earth’s atmosphere was about 280 parts per million by volume (ppmv) in 1750, before the Industrial Revolution began and is rising by about 1.5 ppmv per year (Patawardhan, 2). A study conducted by IPCC compared composition of main greenhouse gases in 1750 and now. The study concluded that the atmospheric concentration of carbon dioxide has increased by 31 percent, methane by 151 percent, and nitrous oxide by 17 percent since 1750 (Enotes.n.pag.).
As these gases absorb or radiate back sun rays to earth, the effect of rise in concentration of these gases is felt in terms of rising global temperatures. Over the twentieth century, the IPCC believes that global temperatures increased close to 0.5 degree Centigrade (C), the largest increase of any century during the past one thousand years (Enotes, n.pag.). The key greenhouse gases that have undergone increase due to human activity are carbon dioxide, methane, nitrous oxide and other gases.
Increase in Level of Carbon Dioxide
Carbon dioxide is the main greenhouse gas and its level in atmosphere has been on the rise. Carbon dioxide is a substance that exists in air naturally, but its composition has been significantly impacted by human intervention in the fast few centuries. The main human activity that emits carbon dioxide is the combustion of fossil fuels (coal, natural gas, and oil) for energy and transportation, although certain industrial processes and land-use changes also emit CO2 (United States Environmental Protection Agency, n.pag.). The burning of fossil fuels is done for the purpose of electricity and power generation, and for running of rising number of heavy and light automobiles. The combustion of fossil fuels such as gasoline and diesel to transport people and goods is the second largest source of carbon dioxide emissions, accounting for about 31% of total U.S. carbon dioxide emissions and 26% of total U.S. greenhouse gas emissions in 2010 (United States Environmental Protection Agency, n.pag.). Thus, increased culture of having personal utility vehicles is an important reason for increasing concentration of carbon dioxide in air.
Rising population of the world is also facilitating the rise of carbon dioxide in air. First, higher population means more exhalation of carbon dioxide in air during the process of human respiration. Second, to support higher population, trees are being cut down and houses are being built. Trees form a filter to convert carbon dioxide into oxygen. Thus, deforestation is affecting the atmospheric composition adversely. It is estimated that, 34 million acres of trees are cut and burned each year resulting in 25% of all carbon dioxide release entering the atmosphere (News Track India, n.pag). This is an alarming number and has already begun affecting human life on earth.
Increase in Level of Methane
The concentration of methane in atmosphere is much less when compared to carbon dioxide, but the former is many times for powerful in absorbing and radiating sun rays back to earth. Thus, rise in methane level is a very serious concern and requires due attention in attempts to control global warming. Methane is 20 times as effective as Carbon dioxide at entrapping heat in the atmosphere and is a leading cause of global warming (News Track India, n.pag). The human interventions that lead to rise of methane level are as follows:
- Methane is formed in marshy land. So, agricultural practices that require marshy land lead to methane formation. Rice or paddy requires high amount of water for cultivation and paddy fields are usually drenched with water and become marshy. This human practice is the main reason for higher methane in air.
- Methane is also produced in abundance in ovine flatulence, bacteria in bogs and fossil fuel manufacture (News Track India, n.pag).
Increase in Level of Other Greenhouse Gases
Human activities have also led to increase in other greenhouse gases. The rise in level of other greenhouse gases, their causes and their impact on global warming is discussed in this section.
First, nitrous oxides are present in small amounts in air. But, this gas has 300 times more capacity of trapping heat than carbon dioxide (News Track India, n.pag). The human activities that cause emission of this gas are agriculture, cattle rearing and by-product of chemical industries.
Second, chlorofluorocarbons are also present in minute quantities in air. This gas has heat-trapping potential thousands of times greater than carbon dioxide (News Track India, n.pag). Thus, even in minute quantities, even slightest increase in its concentration is harmful for human survival. The anthropogenic activities that increase its presence in atmosphere are due to its use in consumer goods and as propellants. The gas has been closely associated with ozone depletion causing harmful solar radiation to reach the other and heat its surface.
Having discussed the anthropogenic activities that facilitate the process of global warming, it is only important to the harmful effects of global warming. First, global warming leads to climatic changes that have lasting impact on humans, animals and all other living beings. Second, it leads to melting of ice caps and increase in sea level. Thus, the land available for human use is on a decrease. Third, storms and other natural events are on the rise as a side effect of global warming. Fourth, global warming is leading to poor performance of crops. Fifth, it is leading to extinction of species that are not able to cope up with the changes associated with global warming.
Conclusion
Global warming is real as its impact is being increasing felt by humans. The effect of global warming is felt in terms of climatic changes, crop failure, nature disasters, melting of ice caps and extinction of species. Global warming is man-made because it is closely associated with anthropogenic activities like rising population, deforestation, rising car culture, industrial revolution, marshy cropping practices like paddy cultivation and fossil fuel manufacturing.
Works Cited
American Policy Roundtable. “The Great Global Warm Up”. Aproundtable.org, 12 Apr. 2007. Web. 21 Mar 2013.
eNotes. “Global Warming”. Enotes.com, 2013. Web. 21 Mar 2013.
National Centre for Policy Analysis (NCPA). “A Global Warming Primer”. Ncpa.org, 2007. Web. 21 Mar 2013.
News Track India. “Major Causes of Global Warming”. Newstrackindia.com, 15 Mar 2012. Web. 21 Mar 2013.
Patwardhan, Anand. “Global Warming and India”. In.undp.org. Web. 21 Mar 2013.
United States Environmental Protection Agency. “Greenhouse Gas Emissions”. Epa.org, 14 Jun 2012. Web. 21 Mar 2013.
Quarterly Journal of Economics 84.3 (1970): 488-500. Web. 17 May 2012.
Mariconda, Simone. “Everyday Economics: A Case of Information Asymmetry”. Echanges-online.ch, 2009. Web. 17 May 2012.
Sagdeo, Anoop. “Economic Impact of Asymmetric Information Theory. Arthsaar.com. Web. 17 May 2012.