... that is believed to be of main concern, as it is a prominent contributor to an 'Enhanced' Greenhouse effect. Since the industrial revolution, CO2 levels have increased by 30 percent, from 280 parts per million per volume in the 1700 (Houghton, J, 2004) to 377.38 ppmv in 2004 (Keeling, C and Whorf, T, 2005) accounting for 55% of total anthropogenic emissions. (Andrews, J et. Al, 1996:181) According to Manahan, "Carbon Dioxide is increasing by about 1ppm per year." (Manahan, 1991:341) Methane (CH4), a component of natural gas has seen increases from 0.7 parts per billion during the pre-industrial period to 1.7 parts per billion (Manahan, 1991:341). Highlighting that; "Methane is going up at a rate of almost 0.02 ppm/year" (Manahan, S, 1991:341) accounting for 15% of total anthropogenic emissions. (Andrews, J et. Al, 1996:181) This is a small but significant increase as 'CH4 is 20-30 times more effective at trapping heat ...

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