When it comes to the amount of methane being pumped into our atmosphere, a new analysis says that the EPA has got its estimates wrong and, thanks to fossil fuels and factory farming, the figure could in fact be significantly higher.
The analysis, published in the journal Proceedings of the National Academy of Science and authored by 15 leading climate change scientists, took a unique look at methane and other greenhouse gas emissions. Instead of using the EPA’s method of collecting data at sources such as outside factory farms and power plants, it instead used sensors on planes and tall towers to measure the level of emissions in the wider atmosphere.
“When we measure methane gas at the atmospheric level,” Harvard professor Steven Wofsy, one of the study’s co-authors, is quoted as saying, “we’re seeing the cumulative effect of emissions that are happening at the surface across a very large region. That includes the sources that were part of the bottom-up inventories, but maybe also things they didn’t think to measure.”
What they found was that their method, which represents one of the most comprehensive studies of greenhouse gasses the United States has seen, showed that the country is pumping out potentially 50% more methane than is currently recorded by government estimates. This would serve to essentially cancel out progress in cutting greenhouse gas emissions achieved to date.
That’s because, while CO2 is often the greenhouse gas to earn column inches, methane is among a handful of gasses that are about 21 times more effective at trapping heat in our atmosphere. The EPA has previously estimated that there are about 32 million tons of methane in the atmosphere, while European agencies have estimated about 29 million tons. Under the new measure, methane levels may be as high as 50 million tons and the obvious conclusion of that is that the lengths we will need to go reduce those damaging gasses will likely have to be much greater.
This follows research by Canadian and Dutch scientists that found standard models for assessing methane production are not appropriate for generating accurate predictions of atmospheric methane or greenhouse gas levels.
“Something is very much off in the inventories,” study co-author Anna Michalak, an Earth scientist at the Carnegie Institution for Science in Stanford, California, is quoted as saying. “The total US impact on the world’s energy budget is different than we thought, and it’s worse.”
The Independent reports the study has been praised by experts in the field who were not involved in the analysis, with Robert Howarth of Cornell University quoted as saying the results are “very compelling and quite important,” while Britton Stephens of the National Center for Atmospheric Research in Boulder, Colorado is reported as saying, “The atmosphere is this great integrator that records the sum of all emissions. The great thing about it is it doesn’t lie, it doesn’t make mistakes.”
Three states, Texas, Kansas and Oklahoma, produce almost one quarter of the United State’s total methane output due to their being centers of fuel production and farming. In particular, cow flatulence and manure have been pegged as one of the central causes of methane because as part of factory farming conditions, manure is often collected into lagoons before being processed, creating ideal conditions for methane release. The world over, it is estimated that livestock and animal husbandry accounts for 18% of all emitted greenhouse gases.
The researchers stress that this study should not necessarily be used to undercut a push for using natural gas as an intermediate between fossil fuels and greener fuels, as some have suggested. Instead, they believe the research is crucial for the fight against greenhouse gas emissions because progress can only be made in any meaningful way if we have accurate estimates of the problem — something that, until now, we appear to have been missing.
Photo credit: Thinkstock.