This week, the internet is full of the discovery of an unexpected methane “hotspot” in the Four Corners region of the United States. A hotspot, in this context, is an unusually high concentration of the gas in one particular area–the highest such concentration in the country, although there are several other such hotspots elsewhere on the planet.
Obviously, the big questions are where did this plume of gas come from and can we–or should we–do anything about it. After all, methane is a greenhouse gas much more powerful than carbon dioxide.
The short version of the story is that the plume was discovered when researchers from NASA and from the University of Michigan analyzed data collected by a European satellite between 2003 and 2009. They then compared that data to other data collected from a ground-based measuring station and concluded that yes, indeed, there is a lot of methane there–almost 10% of the country’s total methane output every year comes from this spot.. The San Juan Basin has been and continues to be heavily exploited for fossil fuel of various types, including natural gas, which is mostly methane. There are, of course, other areas being exploited for natural gas, but none produce so intense a methane plume. The Four Corners area is unusual simply because its equipment (and possibly its rocks as well) are very leaky. That means that yes, we can do something about it, and should; the owners of the equipment should stop the leaks.
Unfortunately, a lot of media outlets, including the venerable Associated Press, have apparently put out stories without actually reading all of the NASA press release, because they variously blame the plume on fracking, coal, or venting of natural gas during coal mining. It’s interesting to note that even generally reliable sources can sometimes be wrong. It’s best to go back to the original source whenever possible, in this case a scientific paper published in a journal called Geophysical Research Letters.
Unfortunately, I cannot access the paper because it’s behind a pay wall that I do not have the cash to scale (I am a poor, humble science writer….). And the sources I can access, so far, leave some of my other questions unaddressed.
But the information I can access still leaves a lot of questions unanswered. Perhaps most importantly, why was this gas plume such a surprise? Apparently, the researchers initially assumed the anomalous reading had to be an equipment malfunction, not a real gas plume.. The real headline here is not that this one spot has a lot of methane but that the previous estimates of methane emissions globally were wrong, possibly really wrong. But why and how? The obvious answer is that the satellites can sense things that ground-based instruments cannot, not that satellites are more accurate (they aren’t) but that they can see places that ground-based sensors cannot access for whatever reason. But in this case researchers used ground-based sensors to check the satellite’s results, so obviously the San Juan Basin is not one of those inaccessible areas.
If we don’t know how much methane is coming out of the ground, our predictions for climate change will be off. If we don’t know where the methane is coming from, we can’t find ways to turn off the flow. We have better answers now, thanks to this discovery, than we did before, and that’s a good thing. President Obama has included looking for methane leaks and addressing them in his plan to stop changing the climate. That’s also a good thing. But it’s odd that none of the sources I’ve read thought it important to report why we didn’t have this information before.
It’s also odd that petroleum industry leaders have downplayed the discovery, arguing (incorrectly) that the methane plume does not matter. After all, the leaks at the San Juan Basin amount to nearly one trillion cubic feet of natural gas. At current prices, and depending on whether we’re talking industrial or residential customers, that could be anywhere from five to seventeen million dollars worth of inventory that is just flying off into the sky there. You’d think somebody would care about that.