Methane emissions playing a growing role in climate change

The international study, led by the French Laboratoire des Sciences du Climat et de l’Environnement (LSCE) reports that methane emissions began to surge in 2007, and then rose precipitously in 2014 and 2015, according to CTV News.

“Additional attention is urgently needed to quantify and reduce methane emissions,” they wrote in Environmental Research Letters journal, summarizing the findings of a consortium of 81 scientists.

While global efforts to combat climate change have focused on reducing carbon dioxide emissions, a by-product of the burning of fossil fuels that accounts for almost 70 percent of warming, little effort has been given to the reduction of methane (CH4) emissions, responsible for 20 percent of climate warming.

Global methane gas emissions from 2010.

EPA/IPCC

Methane is not as prevalent as carbon dioxide in the atmosphere, but it is more potent of the two greenhouse gasses, being 28-times more efficient in trapping the sun’s heat. But as with carbon dioxide, the Earth naturally absorbs and releases methane.

Methane emissions rose slowly between 2002 and 2006. But for the next decade, they climbed 10-times more quickly, to 10 ppb compared to an annual increase of about 0.5 ppb during the early 2000s, according to the study released by the Global Carbon Project, published in the peer-reviewed Earth System Science Data.

The rapid and largely unexplained increase in CH4 emissions between 2014 and 2015 are very worrisome. Marielle Saunois, lead author of the study and assistant professor at Université de Versailles Saint-Quentin, says the high level of methane emissions could threaten worldwide efforts to limit global warming.

“Keeping global warming below two degrees Celsius (3.6 degrees Fahrenheit) is already a challenging target,” the research group says, according to France24. “Such a target will become increasingly difficult if reductions in methane emissions are not also addressed strongly and rapidly.”

The study concludes that methane emissions from increased agricultural activities, most likely biogenic in nature, seem to play a major and possibly dominant role in growing methane emissions. The researchers say we have a great opportunity to reduce methane emissions, along with taking into account global food security and environmental needs.