Published on October 14th, 2016 | by James Ayre0
Methane Emissions From Fossil Fuel Industry Dramatically Higher Than Previously Thought
October 14th, 2016 by James Ayre
Methane emissions from the fossil fuel industry are “dramatically higher” than previously thought, according to a new study published in the journal Nature.
The new study — utilizing the largest database of worldwide methane emissions compiled to date — has revealed that worldwide methane emissions from oil, gas, and coal “production” (extraction, more accurately) are 20–60% higher than current estimates.
To put that in context, that means that the amount of methane emissions previously unaccounted for is roughly 300 times the amount released as part of the Aliso Canyon natural gas leak in California last year. The Aliso Canyon natural gas leak was the largest such leak in US history.
Notably, the new research also found that, when taken as a fraction of total natural gas production, methane leaks/emissions have actually fallen over the last few decades — from around 8% in the mid-1980s, to around 2% in the early 2010s. Total levels have apparently been increasing, though.
As a reminder, methane has a pronounced, but relatively short in duration, effect on the climate as compared to carbon dioxide. When methane breaks down, though, carbon dioxide is released, so the effect on climate doesn’t disappear completely following the period of pronounced effect.
“The good news is that reducing methane emissions now will reduce climate forcing in only a few years — it takes much longer for CO2. And since fossil fuel methane emissions are higher than previously thought, the potential to reduce climate forcing from this specific source is also greater,” commented lead author Stefan Schwietzke, of the University of Colorado and US science agency NOAA, in a conversation with the Guardian.
Here’s some more background from that coverage: “Methane emissions have been rising since the industrial revolution but paused between 1996 and 2006 — believed by some to be because of decreased fossil fuel emissions in former Soviet Union countries — before marching upwards again. Most is from natural sources, such as wetlands and geological seepage, but humanity’s share is estimated to account for 30–45% of the total. The study published on Wednesday examined the isotopic ‘fingerprints’ of methane sources, compiling thousands of measurements from public sources and peer-reviewed papers. Allen said it was the largest database of its kind.”
Reducing methane emissions may reduce climate forcing faster than previously thought, as Schwietzke guesses (or not), but reducing methane emissions is not a simple proposition. To truly reduce methane emissions to a meaningful degree would require a fundamental restructuring of the energy, agricultural, and transportation sectors. If such transformations happen, they won’t be fast, and they likely won’t be made willingly (particularly with regard to the agricultural sector).