Methane: A Scientific Journey from Obscurity to Climate Super-Stardom NASA

The first survey in 1971 on the possibility of inadvertent human modification of climate stated that “Methane has no direct effects on the climate or the biosphere [and] it is considered to be of no importance”. The gas did not even appear in the index of the major climatology book of the time (Lamb’s Climate Past, Present and Future). Yet in the 2001 IPCC report, large parts of multiple chapters are dedicated to examining the sources, sinks, chemistry, history and potential future of this humble molecule. New papers are published every month relating paleo-climate changes to methane variability and discussing the possibility of significantly reducing future anthropogenic climate change by aggressively managing methane emissions. New hypotheses such as the “clathrate gun hypothesis” place methane variability at the centre of the debate on rapid climate change. What has fueled the rapid rise of methane from an obscure trace gas to a major factor in past, present and future climate change? As is usual in science, it is the conflation of multiple lines of evidence, that only when taken together do the connections and possible feedbacks seem obvious.