October 25, 2008

Increasing Greenhouse Gases Cause Concern

Carbon dioxide is only one of the greenhouse gases that make scientists stay up at night. Methane and nitrogen trifluoride are increasing which makes scientists worry about increasing global warming. 

Methane is the greatest threat. It represents about one-third that of carbon dioxide produced by the burning of coal, oil and other fossil fuels.  As a greenhouse gas, methane is second to carbon dioxide. 

Decaying plant material, land fills, natural gas, coal mining and animal waste produces methane. Decaying plants causes the greatest worry. Decaying Artic plants produced billions of tons of methane which is trapped in permafrost wetlands and under the ocean floor. Global warming could release this gas.

Scientists cannot tell for sure but there could be signs that this release could be starting. In 2006, after eight years of stable levels, the amount of methane in the atmosphere started to rise.  This is not good news according to scientists like Ron Prinn. Prinn said that an increase in methane will increase the rate of climate change.

Nitrogen trifluoride has been considered a small concern that is used as cleaning agent during the production of liquid crystal displays for televisions and computer monitors and for thin-film solar panels. Previous efforts to measure the amount of nitrogen trifluoride in the atmosphere underestimated the levels said Roy Weiss from the Scripps Institution of Oceanography. Levels of this gas have gone up by a factor of 4 over the last ten years. 

Nitrogen trifluoride, while its contribution to global warming is small compared to man-made carbon dioxide, is much better at trapping heat. As a heat trap, it is thousands of times stronger. By comparison, methane, per molecule, is only 20 times for effective than carbon dioxide. Carbon dioxide remains the greatest threat to global warming due to large amounts and rapid growth. 

Methane will probably increase in the near future as more of the greenhouse gas is released in the shallow parts of the Artic Ocean.