A 21st-century shift from fossil-fuel to biogenic methane emissions indicated by 13CH4

@article{Schaefer2016A2S,
  title={A 21st-century shift from fossil-fuel to biogenic methane emissions indicated by 13CH4},
  author={Hinrich Schaefer and Sara E. Mikaloff Fletcher and Cordelia Veidt and Keith R. Lassey and Gordon W. Brailsford and Tony Bromley and Edward J. Dlugokencky and Sylvia E. Michel and J B Miller and Ingeborg Levin and David C. Lowe and Ross J. Martin and Bruce H. Vaughn and James W. C. White},
  journal={Science},
  year={2016},
  volume={352},
  pages={80 - 84}
}
Getting a rise out of agriculture Methane, a powerful and important greenhouse gas, has been accumulating nearly uninterruptedly in the atmosphere for the past 200 years, with the exception of a mysterious plateau between 1999 and 2006. Schaefer et al. measured methane's carbon isotopic composition in samples collected over the past 35 years in order to constrain the cause of the pause. Lower thermogenic emissions or variations in the hydroxyldriven methane sink caused the plateau. Thermogenic… 
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