Methane oxidation, biogenic carbon, and the IPCC’s emission metrics. Proposal for a consistent greenhouse-gas accounting

Abstract

Purpose The fifth assessment report by the IPCC includes methane oxidation as an additional indirect effect in the global warming potential (GWP) and global temperature potential (GTP) values for methane. An analysis of the figures provided by the IPCC reveals they lead to different outcomes measured in CO2-eq., depending on whether or not biogenic CO2 emissions are considered neutral. In this article, we discuss this inconsistency and propose a correction.