Methane finding baffles scientists

[摘要] The startling discovery that terrestrial plants produce the greenhouse gas methane is sending scientists and a few politicians back to the drawing board. Climate researchers are amazed by the discovery as they could have missed what is potentially a huge methane source. Methane is the second most important greenhouse gas in the atmosphere after carbon dioxide. Scientists had thought they knew about all the significant methane sources and how much each contributed but now it seems that their figures were very wrong.