Author’s response to commentary on “Carbon balance effects of U.S. biofuel production and use”

摘要: The impact of substituting biofuels for fossil fuels on carbon dioxide (CO2) emissions has been debated many years. A reason the lack resolution is that method widely used to address question, lifecycle analysis (LCA), subjective. Its results irreducibly depend untestable assumptions, notably those pertaining system boundaries but also representing market effects. best one can do empirically constrain estimates net CO2 using data characterize important aspects overall system. Our 2016 paper, “Carbon balance effects U.S. biofuel production and use,” took such an approach, field estimate direct exchanges a circumscribed vehicle-fuel over 2005–2013 period expanding US use. De Kleine colleagues criticize our work because it does not follow LCA conventions, arguing in particular primacy assumption are inherently neutral. This response refutes their critique; reminds readers why paradigm fails dynamic involving terrestrial cycle, stresses need bound key exchanges, explains circular logic be so beguiling.