Ask A Scientist Environmental Earth Science Archive

 
name         Louise W.
status       student
age          20s

Question -   Despite the grotesque deforestation for cattle farming, I wonder if you could 
tell me if the methane produced by the animals while living is thought to be a significant 
contributor to global warming.
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Dear Louise-

  There are many sources for methane, with livestock production making up a significant 
  fraction of the total methane production from anthropogenic sources.  The EPA estimates 
  that, for the U.S., about 25 percent of the total methane generated from anthropogentic 
  sources comes from domesticated livestock and their manure.  Here are a couple of good 
  web sites concerning
methane production:

        http://www.epa.gov/ghginfo/topics/topic4.htm
        http://www.epa.gov/ghginfo/topics/topic2.htm#anthro

Methane only comprises about 13 percent of the 4 greenhouse gases along with water vapor 
that create the natural greenhouse effect. Carbon dioxide comprises about 76 percent of
the total.  Here is another link you might find useful:

    http://globalwarming.enviroweb.org/ishappening/sources/index.html

Good luck on your study of greenhouse gases and global warming...!

Wendell Bechtold, meteorologist
Forecaster, National Weather Service
Weather Forecast Office, St. Louis, MO
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