|Methane Hydrate / Clathrate|
Observers of the warming oceans have considered many impacts which that warming will have.
On one issue, their are two camps, one saying hydrates will substantially contribute to human extinction, and the other saying it will not.
In other words, the verbal battle lines are well defined.
However, we have to look closer if we want to understand the issues.
So let's take a look.
I am not ready to conclude in this post, rather, I am only laying the issue out on the table for consideration at this time.
II. Basic Views of the Two Camps
A. The Clathrate Catastrophe Camp
The Nature Bats Last blog sets forth the near term human extinction (NTHE) position:
By 15 December 2013, methane bubbling up from the seafloor of the Arctic Ocean had sufficient force to prevent sea ice from forming in the area. Nearly two years after his initial, oft-disparaged analysis, Malcolm Light concluded on 22 December 2013, “we have passed the methane hydrate tipping point and are now accelerating into extinction as the methane hydrate ‘Clathrate Gun’ has begun firing volleys of methane into the Arctic atmosphere.” According to Light’s analysis in late 2013, the temperature of Earth’s atmosphere will resemble that of Venus before 2100.(Nature Bats Last). The "clathrate gun" reference is sometimes called a hypothesis (Clathrate Gun Hypothesis).
B. The "Nothing To See Here, Move Along Folks" Camp
This camp has some formidable members too, who plainly say that the other camp is a bit over the top:
News stories and Web postings have raised concerns that climate warming will release large volumes of methane from gas hydrates, kicking off a chain reaction of warming and methane releases. But recent research indicates that most of the world’s gas hydrate deposits should remain stable for the next few thousand years. Of the gas hydrates likely to become unstable, few are likely to release methane that could reach the atmosphere and intensify climate warming.(USGS: Why a Methane Catastrophe Is Unlikely). Ok, we see that distinct debate lines, on a very important subject, have been drawn.
III. The Admitted Unknowns
A. How Much
The USGS indicates that there are no tools with which to determine which source current atmospheric methane comes from:
The atmospheric concentration of methane, like that of carbon dioxide, has increased since the onset of the Industrial Revolution (fig. 5). Methane in the atmosphere comes from many sources, including wetlands, rice cultivation, termites, cows and other ruminants, forest fires, and fossil fuel production (fig. 6). Some researchers have estimated that up to 2 percent of atmospheric methane may originate with dissociation of global gas hydrates. Currently, scientists do not have a tool to say with certainty how much, or if any, atmospheric methane comes from hydrates.(USGS: Gas Hydrates and Climate Warming, emphasis added). Of the "2 percent" of atmospheric methane in the air we breathe, it is not known how much of it comes from methane hydrates that have broken down and released their caged methane.
B. Lack of Research and Data?
A lot of attention is being paid to the matter, however, some say the science has not yet matured:
In the field of methane emission research today, the Arctic is one of the most important regions worldwide. It is believed that methane occurs there both in the form of gas hydrate in the sea and as free gas trapped in the deep-frozen permafrost. Methane deposits in permafrost and hydrates are considered to be very sensitive in the expansive shallow-shelf regions, because with the relatively low pressures it would only take a small temperature change to release large amounts of methane. In addition, new methane is continuously being produced because the Arctic regions are rich in organic material that is decomposed by microbes in the sediment. The activity of these microbes and thus the biological release rates of methane are also stimulated by increases in temperature. Hence methane emissions in the Arctic have multiple sources. International scientific consortia are now being established involving researchers from various disciplines – chemists, biologists, geologists, geophysicists, meteorologists – which are intensively addressing this problem. No one can yet say with certainty how the methane release in the Arctic will develop with global warming, either in the ocean or on the land. This research is still in its infancy.(World Ocean Review, p. 2, emphasis added). How such an important issue leaves scientists in the dark because of methane clathrate research immaturity is troubling.
C. Jury Still Out?
One good place to observe the dynamic back and forth is a Guardian piece:
Can scientists overcome huge uncertainties to pin down how close, or far, we might be to a tipping point?(Why The Jury's Still Out). The jury is out for some people, but not out for others it would seem.
About a week ago, climate scientist Michael Tobis wrote a critique of my 'Seven facts about the Arctic methane time bomb' following a twitter exchange with him and Chris Colose, author of an article at Skeptical Science arguing that the core scenario of a new Nature paper by Gail Whiteman et. al on the economic costs of Arctic climate change is extremely unlikely.
Much of this debate kicked off because the said Nature paper advances a hypothetical scenario for an abrupt Arctic methane release over either a decade or several decades of about 50 gigatonnes (Gt), and argues specifically that such a scenario is "likely." My own attempt to understand the literature convinced me that the scenario should be viewed as a serious possibility.
Tobis on the other hand is the latest amongst several scientists offering scathing criticisms of that scenario, which in his own words is "as close to impossible as anything in earth science; actual geophysics refutes it."
He begins with my first point, 1. The 50 Gigatonne decadal methane pulse scenario was posited by four Arctic specialists, and is considered plausible by Met Office scientists.
Tobis writes that the Review of Geophysics paper I cite says
"Arctic thawing may release in excess of 50 GT of C [Carbon], a very serious matter... But Ahmed refers to the paper in support of a very different assertion, that 50 GT of methane would be released... But the paper to which he points says nothing of the sort. I conclude that he doesn't really know what he is talking about. Specifically he has already shown that he is confused about the distinction between methane releases and CO2 releases."However, the carbon release scenarios from permafrost explored by the paper include both methane and carbon. Here's what the paper says:
"The most important determinant of whether release of frozen carbon happens as CO2 or CH4 [methane] is whether decomposition proceeds aerobically or anaerobically... In anaerobic conditions, a greater proportion of soil organic carbon decomposition is released as CH4, although not all of it necessarily reaches the atmosphere."Following this paragraph, the paper cites several scenarios for large-scale releases from permafrost carbon, including the 50-100 Gt carbon release I mentioned.
IV. Some Other Scientists Speak Out Boldly
An expert on the Siberian Arctic methane hydrate scenario has published some papers indicating that a serious condition exists:
Extremely high concentrations of methane (up to 8 ppm) in the atmospheric layer above the sea surface along with anomalously high concentrations of dissolved methane in the water column (up to 560 nM, or 12000% of super saturation), registered during a summertime cruise over the ESS in September 2005, were analyzed together with available data obtained during previous and subsequent expeditions to distinguish between possible methane sources of different origin, potential, and mobility. Using indirect evidence it was shown that one such source may be highly potential and extremely mobile shallow methane hydrates, whose stability zone is seabed permafrost-related and could be disturbed upon permafrost development, degradation, and thawing. Further immobilization of stored methane could cause abrupt methane release and unpredictable climatic consequences.(Geophysical Research Abstracts, by Shakhova et al., PDF; cf this). I will refer to one other scientist before closing:
Paul Beckwith, a climatology and meteorology professor at the University of Ottawa, Canada, is an engineer and physicist who researches abrupt climate change in both the present day and in the paleoclimatology records of the deep past.(The Methane Monster Roars). This year is still struggling to become the record year, by having the lowest Arctic sea ice extent of all other years.
“It is my view that our climate system is in early stages of abrupt climate change that, unchecked, will lead to a temperature rise of 5 to 6 degrees Celsius within a decade or two,” Beckwith told me. “Obviously, such a large change in the climate system will have unprecedented effects on the health and well-being of every plant and animal on our planet.”
That is, the lowest since the recent record was set in the year 2012 (Arctic Ice Extent: 2015 Struggles For First Place - 2).
The Obama Administration's allowing Arctic area drilling to find more of the poison that is threatening civilization was a deadly event, all their promises to cut poison GHG emissions notwithstanding.
Dr. Shakhova camp: