The blogosphere for years has been abuzz, and particularly in recent weeks, with information – and, equally importantly, misinformation – about the near-term risks posed by uncontrollable and potentially catastrophic releases of large Arctic deposits of methane hydrates, ice-like substances holding a powerful greenhouse gas.
Highly vocal have been voices cautioning about existing or perhaps imminent methane releases to the atmosphere, resulting in global catastrophe or cataclysm and threatening human civilization.
Such concerned voices in recent weeks are the focus of this post, as many appear to be in response to the January 29 post of videographer Peter Sinclair’s monthly video, at this site. That video included interviews with several highly regarded experts pushing back on the doom-and-gloom “methane time bomb” meme.
It’s no surprise that some of those recent and ongoing online commentaries mischaracterize the expert perspectives reflected in that January 29 video. One comes to expect that of the online world of commentary and hyperbole.”The Click To Tweet
Carolyn Ruppel, PhD, who heads the gas hydrates research project for the United States Geological Survey, USGS, is among those featured in that video, along with other reputable scientists.
But given constraints on how much information could be included in that single six-minute video, we provide here six brief educational videos – ranging from one minute to nearly five minutes – drawn from the Ruppel interview remarks not included in that initial video.
These six segments provide authoritative background on the “methane time bomb” and why experts may not “lie awake at night” fretting about it.
Watch Video Part 1 (Duration: 4:46)
In this video, Ruppel explains the fundamentals of methane hydrates, where they are concentrated, and why. The areas of greatest concern are in the Arctic continental shelf, which during the last glaciation, when sea level was lower, were vast northern permafrost grasslands. This “Serengeti of the North,” as climate scientist Ben Abbott of Brigham Young University has called it, helped lay down massive layers of vegetation and living remains, now frozen in permafrost. And in that frozen permafrost are isolated deposits of methane hydrate, a potent greenhouse gas.
As the glaciers retreated as a result of changes in Earth’s orbit, oceans rose and flooded large areas of permafrost coastal plain, forming an extended Arctic Ocean shelf. In that shelf area, relatively warm ocean waters may cause those hydrates to break down.
Ruppel explains, however, that because hydrates can concentrate only in certain types of soils, they are not as widespread as some people believe, and huge methane releases from hydrates have not been confirmed in these areas.
Watch Video Part 2 (Duration: 1:28)
In this video, Ruppel discusses newly described areas in the Barents Sea where pockmarks have been discovered on the sea floor. These may be indications of methane releases from deposits that formed under an ice sheet that covered the area during the glacial maximum. “That is a new environment,” Ruppel says, “but that doesn’t mean we need to panic about the amount of methane that’s coming out.”
Watch Video Part 3 (Duration: 1:16)
In this third video, Ruppel explains that deposits of methane hydrate in the Arctic typically coincide with areas of conventional oil and gas deposits, and leaks from those deposits may be the source of the hydrate deposits. “They are not ubiquitous,” she says, “and the amount may not be as large as people might think it is.”
Watch Video Part 4 (Duration: 1:11)
Ruppel here explains that ocean waters are under-saturated with methane, meaning that for releases from waters more than 100 meters deep, methane tends to be absorbed in the water column before reaching the surface. “It’s not a freight train that this methane is going to wind up directly in the atmosphere.”
Watch Video Part 5 (Duration: 1:01)
Ruppel here discusses what she calls a common “misconception” involving the risk of a “catastrophic trigger” of methane releases. The thermodynamic properties of methane hydrate render that fear “not a scientifically sound worry,” she says. “That is simply not how these deposits can function thermodynamically.” She explains that the reaction that releases methane is “endothermic.” The significance of that, she says, is that the methane absorbs heat from the surroundings, and the methane “keeps shutting itself down.”
Watch Video Part 6 (Duration: 1:47)
Here Ruppel points out that “methane seepage is not new … in geophysics, the tools have changed quite a bit in the last decade … you can actually do this with your fish finder. Go out on a lake, turn your fish finder on, and you may find methane coming out. We have the tools to routinely image the water column, and that is why we are finding methane coming out everywhere.”
“It would be inappropriate for us to portray them as new, just started happening,” she advises.
Editor’s note: This post and the six videos were updated on 2/9/19 to correct the date the interviews were conducted.