Carbon dioxide is a naturally occurring gas which is produced by the plants, animals and microorganisms. This gas is continuously being exchanged between the atmosphere, land and ocean’s surface in a balanced way (Mader 2011).
Various human activities which began after the industrial revolution that took place in the 1800 has contributed significantly to the buildup of CO2 in the atmosphere. About 3 to 6% of the CO2 in the atmosphere is due to human activities. Although it is less when compared to the emission of CO2 by natural causes like volcanic eruptions, the balance of emission and absorption of the CO2 has been disrupted primarily because of the human activities. The major source of CO2 emission is by burning of fossil fuels like oil, coal and natural gas by driving vehicles, heating, and production of electricity. Burning of forests and causing deforestation to create land of agricultural purposes and for providing living space of the growing population is also a major contributing factor for the increase in the CO2 level in the atmosphere. Studies have found that the level of CO2 has increased worldwide from around 0.028% which was in the 1800 to 0.0365% in 2010. Although the difference does not look significant, it indicates that every year almost 3 million metric tons of CO2 are being added to the atmosphere by human activities alone (Edward and Miller 2001; Mader 2011; NRC 2010).
A part of the sunlight when it reaches earth gets absorbed and a part of it gets reflected back. The absorbed sunlight gets converted to heat which gets released in the form of infrared radiations into the atmosphere. One of the properties of the carbon dioxide which is also a major green house gas is the absorption of heat. The heat released is absorbed by the CO2 along with other green house gases like the nitrous oxide, water vapors and methane present in the atmosphere. As the concentration of CO2 increases in the atmosphere more heat gets trapped which would result in the earth’s atmospheric temperature to go up significantly. Studies have found there has been a 0.6°C rise in the global climate from the time of industrial revolution. It has been predicted that there could be a 1.5 to 4.5°C increase in the temperature by the year 2100 if the current trend of emission of greenhouse gases like CO2, methane, nitrous oxide and water vapor continues. This would cause the water in the ocean would become warm; the glaciers will melt which in turn increase the oceans water level; more water will evaporate causing increased rainfall which would cause flooding affecting the life on earth, etc. So by the increase in the earth’s temperature the overall global climate would be affected (Karl et al. 2009; Mader 2011).
Finally to summarize, there is no doubt that various human activities is causing the CO2 levels to increase in the atmosphere which in turn is causing the changes in the climate. However, by adapting alternative source of energies that would replace the use of oil, fuel and natural gases like solar energy and wind energy for various human activities would reduce the addition of CO2 to the environment and prevent further damage to the climate (Mader 2011).
References
Edward PG and Miller CA. 2001. Changing the atmosphere: expert knowledge and
environmental governance. Cambridge Mass: MIT Press.
Karl TR, Melillo JM, and Peterson TC. 2009. Global climate change impacts in the United States. United States Global Change Research Program. New York, NY, USA: Cambridge University Press.
Mader S. 2011. Human Biology. 12th ed. New York, NY: McGraw Hill Publishers.
NRC. 2010. Advancing the Science of Climate Change. National Research Council. The National Academies Press, Washington, DC, USA. [Accessed on March 21, 2013]. Available from:
http://nas-sites.org/americasclimatechoices/sample-page/panel-reports/87-2/
