A newly published paper by Dr. Hanqin Tian, director of International Center for Climate and Global Change Research at Auburn University, has been featured on the website of the North American Carbon Program, a core element of the U.S. Global Change Research Program. The paper represents the first estimation of the overall global warming potential of all three major greenhouse gases (carbon dioxide, methane and nitrous oxide) in North American terrestrial ecosystems. The Auburn University researchers, Dr. Hanqin Tian, Dr. Chaoqun Lu, Dr. Susan Pan, and Dr. Wei Ren, teamed up with scientists from Harvard University, Oak Ridge National Laboratory and Northern Arizona University to implement this pioneer work.
The team found that the emissions of methane and nitrous oxide offset about 73% of the land carbon dioxide sink in the North American continent, and the offset rates varied widely among countries (57% in the US, 83% in Canada, and 329% in Mexico). The research further indicates that terrestrial ecosystems in North American might act as a significant contributor to global warming in extreme drought. The highest positive GWP was generally located in wetland areas (due to high methane emissions) and tropical forests of eastern Mexico (due to high carbon dioxide and nitrous oxide emissions). Positive GWPs were found in Alaska, Nevada, Florida, Louisiana, and most states in Mexico, indicating these zones were potential contributors to global warming.
Visit the North American Carbon Program website for a detailed synopsis, including a summary of the new science and significance of the research: http://www.nacarbon.org/nacp/documents/WWRMay2014Tian.pdf .