A new study released in the Proceedings of the National Academy of Sciences suggests the level of methane in the atmosphere is greater than previously understood.

Prior studies relied on computer models but this study is from measurements taken from over 13,000 plane flights in 2008 and represents the largest collection of data.  According to the publication, the U.S. poured 49 million tons of methane in 2008.

References

Miller, S.M., Wofsya, S.C., Michalakb, A.M., Kortc, E.A., Andrewsd, A.E., Biraude, S.C., et. al. (2013, November 25). Anthropogenic emissions of methane in the United States. Proceedings of the National Academy of Sciences. Retrieved December 5, 2013, from http://www.pnas.org/content/early/2013/11/20/1314392110.abstract

Further Reading

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