Blog Archive

Friday, January 27, 2012

Gary Houser's rebuttal: RealClimate's David Archer wrong to dismiss concern about potential methane runaway in Arctic: Why this threat is real and the imperative to exercise the Precautionary Principle when the stakes are this high


               Why This Threat Is Real and the Imperative to Exercise
               the Precautionary Principle When the Stakes Are This High

          We carried out checks at about 115 stationary points and discovered
          methane fields of a fantastic scale - I think on a scale not seen before... 
          This is the first time we've found continuous, powerful and impressive
          seeping structures more than 1,000 meters in diameter. It's amazing.  
          -- Dr. Igor Semiletov (crew leader of Sept.-Oct. 2011, U.S.-Russian
           methane expedition in interview with the UK Independent) [1]

In the first sentence of his January 4, 2012, entry on the "RealClimate" blog [2], David Archer links to a rebuttal I wrote to oppose blogger Andrew Revkin's "Dot Earth" dismissal of an article in the UK Independent about dramatic new observations of methane emissions in the Arctic [3]. Archer portrayed this rebuttal as an example of someone getting people un-necessarily "worked up" about the issue. As the co-producer of a documentary who has interviewed several leading-edge scientists on this topic, I have asked for space to respond. With all due respect to Archer, the result of these interactions has been a strong sense of urgency that stands in stark contrast to his dismissive stance.

Growing Concern About Rising Arctic Temperatures and Impact on Methane

It is acknowledged that the Arctic is the most rapidly warming region on earth. As indicators point toward a near-term loss of ice cover in the Arctic (with some studies pointing toward a late summer ice-free condition as soon as 2015 [4]), there is a growing concern about how amplification of Arctic temperatures will affect the massive deposits of frozen methane in the shallow seabeds of the continental shelf areas. Researchers on the "front line" in the Arctic gathering empirical evidence (e.g., Igor Semiletov and Natalia Shakhova) are now reporting methane plume activity on a scale not witnessed before now.

These observations were reported in the UK Independent and since that time have stirred up controversy as to whether humanity may be receiving a first glimpse of a situation that could escalate into one of the scenarios most feared by climate scientists -- an unstoppable positive feedback known as a methane "runaway" event. This controversy has been reflected in the above-described exchange on "Dot Earth" and is now expanding to RealClimate, and even more recently to Joe Romm's "Climate Progress." On January 11, Romm wrote about how the methane situation is combining with other factors to create an urgent danger in the Arctic [5].  The twin issues of contention in this controversy have been whether the methane threat is real and whether it is imminent, therefore deserving the urgent attention of the world.  

The Big Picture Context of the Methane Controversy

Before launching into a discussion of those two points, it would seem useful to explore the larger context. A key question deserving exploration would be "What is at stake?"  What are the potential consequences if humanity fails to pick up on warning signs and a methane runaway event becomes unleashed?

The topic at hand is what most climate scientists would likely see as the worst case "night- mare" scenario which could lead to a total global catastrophe. We are talking about a greenhouse gas that has a full 72 times more powerful warming impact than CO2 within the first 20 years [6].  We are talking about a global stockpile that contains as much carbon as all the world's known reserves of coal, oil, and natural gas combined. If there is even a chance that significant amounts might be released into the atmosphere by an unstoppable methane "runaway,"  a profound moral responsibility exists to approach the topic with utmost care and caution.

What is a Methane "Runaway" Event?
The term is defined by Ira Leifer (methane researcher at the Marine Science Institute at the University of California-Santa Barbara):

    A runaway feedback effect would be where methane comes out of the ocean
    into the atmosphere leading to warming, leading to warmer oceans and more
    methane coming out, causing an accelerated rate of warming in what one could 
    describe as a runaway train.  [7]

Due to the enormous size of the methane deposits, this process would "feed" on itself in a way that humanity would most likely be helpless to stop.

Possible Key Role of Methane in Two Mass Extinctions, Including Worst in Earth's History

In order to ascertain what kind of potential threat methane may be in the present context, it is important to look at earlier periods on earth when methane may well have played a key role in the most devastating mass extinction events in the geological record. Although not a "lock" in terms of absolute "proof," very strong circumstantial evidence points toward a major role of methane in two of these events. One is the "End-Permian" in which severe global warming led to such extreme heat and depletion of oxygen that over 90% of life forms were wiped out [8]. One attempt to take this association out of the abstract and make it more tangible can be seen in a nine-minute segment (highly recommended) from the acclaimed documentary series"Miracle Planet" [9].   

James Hansen relates methane to another extinction event -- the Paleocene-Eocene Thermal Maximum or PETM: 

    There have been times in the earth's history when methane hydrates on the 
    continental shelves melted and went into the atmosphere and caused global
    warming of six to nine degrees Celsius, which is 10 to 18 degrees Fahrenheit. [10]

    It is difficult to imagine how the methane clathrates could survive, once the ocean  
    has had time to warm. In that event a PETM-like warming could be added on top
    of the fossil fuel warming. [11]   

We are clearly dealing with a destructive force of almost unimaginable power, which under-lines my earlier warning that it be approached with utmost caution.


Are the Factors Present Which Could Lead to a Runaway?   

In exercising such appropriate caution in dealing with a force of this magnitude, a logical question would be to ask whether the factors are now existent (or may soon be in the very near future) which could potentially unleash such a runaway. Here are several factors which are already present:
  • The incredible warming power of methane as a greenhouse gas (already quantified)  
  • The phenomenally huge volume of methane present in the continental shelf areas of the Arctic  
  • The quite shallow depth of these seabeds, which allows direct venting to the surface and atmosphere (methane otherwise safely oxidizes in deep water)
  • Their location in the most rapidly warming region on earth, where such is accelerating due to the "albedo flip" (open water now absorbing solar heat rather than having it reflected away by ice cover) and warmer water infiltrating at the river mouths
  • Direct observations confirming that large scale methane plumes are venting to the surface and into the atmosphere, and 
  • Direct observations confirming that seabed bottom temperatures are hovering at the thaw point. [12] 
20 Degree (Fahrenheit) Rise in Arctic Temperature by 2095

A study by the Massachusetts Institute of Technology (M.I.T.) projects how much temperature rise could be expected in the Arctic by the year 2095 if world governments continue on a business-as-usual path. Its projection is an astounding 20 degrees (F) [13].  Even more astonishing, this projection does not even consider how feedbacks could amplify this warming even further. According to study co-author Ronald Prinn:  

      And the odds indicated by this modeling may actually understate the problem, 
      because the model does not fully incorporate other positive feedbacks that can
      occur, for example, if increased temperatures caused a large-scale melting of
      permafrost in Arctic regions and subsequent release of large quantities of
      methane, a very potent greenhouse gas. Including that feedback “is just going
      to make it worse. [14]

While it is not possible to pinpoint any particular time when a release of methane might hit "critical mass" and initiate the runaway, it certainly appears the necessary ingredients are present and a collision course has been set up. The question is no longer "if" but "when." 

With the Arctic warming so much faster than the rest of the world and arriving at such incredible temperatures within this century, it is clear that the "writing is on the wall" in terms of the future of methane in the shallow Arctic seabeds. Unless there is a major shift away from the "business as usual" scenario, it is inevitable that they will thaw and vent into the atmosphere.  
How Soon Could Late Summer Ice-Free Conditions Accelerate the Warm-up?
Most climate observers agree that the steady temperature climb in the Arctic will only accelerate once late summer ice-free conditions set in.  Even with such astounding projections as that by M.I.T., the situation is actually more frightening and urgent. Almost every prediction of how rapidly climate impacts will occur has been out-paced by developments in the real world. If this consistent pattern repeats in regard to loss of Arctic sea ice (as it most likely will), the threat to hydrate stability will accelerate even more quickly. The Inter-governmental Panel on Climate Change (IPCC) has been projecting a late summer ice-free Arctic by summer 2030. But experts who say that loss of ice thickness should be factored in, as well as loss of surface ice, are pointing toward an ice-free condition as early as 2015 [15]. 
One of the top experts on Arctic ice -- Peter Wadhams of the University of Cambridge in the UK -- supports the PIOMAS sea ice volume model [16].
Wadhams is concerned that the collapse could prove to be a point of no return for the ice:

    It is really showing the fall-off in ice volume is so fast that it is going to bring us
    to zero very quickly. 2015 is a very serious prediction, and I think I am pretty
    much persuaded that's when it will happen. [17]  

Archer Acknowledges Power of Methane and Vulnerability (especially in the Arctic) 
In a piece Archer co-authored in 2009 [18], he acknowledged both the destructive power of methane and the fragile and "intrinsically vulnerable" nature of hydrates:     

    There are concerns that climate change could trigger significant
    methane releases from hydrates and thus could lead to strong positive
    carbon–climate feedbacks. .... Methane hydrate seems intrinsically
    vulnerable on Earth; nowhere at the Earth's surface is it stable to
    melting and release of the methane.

In this same piece, Archer affirms another key factor regarding this vulnerability:

    Rapid warming well above the global average makes the Arctic hydrates
    particularly vulnerable to climate change.  

In his current post, he alludes to the immense scale of these methane stockpiles and continues to outline the parameters of what is at least an extremely significant potential threat: 

    The total amount of methane as ocean hydrates is poorly constrained but
    could rival the rest of the fossil fuels combined.

It is significant that Archer acknowledges that the potential exists for a large scale positive methane feedback to occur. Where we disagree is in our assessment of how serious and how urgent this threat is.


Six Direct Challenges to David Archer

1) Human Warming  *ON TOP OF*  Natural Warming
Having acknowledged several key reasons why methane poses at least a very large potential threat to humanity, it is difficult to comprehend why Archer would set himself up as a naysayer and try to discredit those who see indications that this potential might soon become a reality. One of the ways he tries to do this is to point toward the possibility of natural geothermal warming coming up from below and ask the question: how do we know the plumes are coming from new, human-created warming?  But this question severely misses the point and throws the conversation off track. If indeed there is pre-existing warming coming from below, then this is only going to combine with human-made warming from above to create an even more volatile and dangerous situation.  

If the permafrost cap is becoming perforated (as suggested by Shakhova), then the hydrates may become subject to de-stabilization from both directions.

2)  Arctic Warming Already Approaching Methane Thaw Point in Shallow Seabeds 

Archer does not address the reports of scientists in the field who are describing how close the water temperature in the shallow seabeds is hovering near the thaw point. Igor SemiIetov (the crew leader of the recent U.S.-Russian methane expedition supported by the National Science Foundation) has been tracking the Arctic methane issue for over 15 years. In an interview for our documentary, he shared these remarkable comments on thaw points and warmer water at the surface being driven to deeper depths by increased levels of wind and wave action as the ice cover retreats:  

When ice has gone, there are stronger winds and waves and a deeper mixing of water which causes the comparatively warm upper layer to mix with water at deeper levels. There are already studies which confirm that in some areas, bottom temperature in summer is 2 to 3 degrees above zero celsius (freezing). This means that when we determine average temperature of the year, it is already somewhere close to zero degrees celsius (the freezing-thaw point)...  As this warming spreads to a larger area, the more that shelf-based permafrost will thaw. [19]   

3)  With Methane On Verge of Thawing Within Decades, How Does Archer Defend Complacency? 
With methane-laden areas already so close to a thaw point, it becomes a critical question to determine how rapidly the temperatures in the Arctic will increase. Once the ice cover undergoes collapse, there is nothing to prevent an escalation of Arctic warming. Under the business as usual scenario, we are seeing stunning projections of how warm the Arctic could become within this century -- such as the M.I.T. study. These projections create a collision course whereby currently frozen methane will inevitably thaw. Now a strong case emerges that ice loss could happen even more rapidly than originally speculated, expanding the same open water that Semiletov says is driving warm temperatures downward to the seabed. With such a prospect of a warming Arctic releasing the colossal methane deposits, how does Archer defend the case for complacency?    

I would ask him to respond to two science articles (illustrated with graphics) by Sam Carana,  a member of the Arctic Methane Emergency Group (AMEG) which presented a poster, distributed a brochure, and gave a presentation at the American Geophysical Union (AGU) conference in San Francisco in December 2011. Carana explores the connection between ice loss, warming temperatures in the Arctic, and the release of methane [20, 21].
4) Grasping Irreversibility, Dropping Insistence on Absolute Evidence That May Come Too Late

Archer portrays the "alarmist" crowd as predicting a runaway within the next few years. This is not true. What they are saying is that a process may be initiated which could lead to a runaway. Sam Carana speaks to this point:

The danger is that if relatively large amounts of methane are released abruptly into the atmosphere in the Arctic, they will persist for decades, triggering yet further temperature rises and methane releases, in a vicious cycle leading to runaway global warming, even if the world did manage to take the necessary steps to dramatically reduce emissions. [22] 

As it is the definition of "runaway" that such a feedback will be all but impossible to stop once it starts, the only option for humanity is to act preventatively. When Archer continues the quest for some kind of absolute "smoking gun" evidence that the methane emissions now occurring are being caused by human-made warming, it seems he is having trouble -- as are many people -- in grasping the full meaning of the concept of IRREVERSIBILITY. This quest is wrong not only for the reason shared earlier but because at the point this causal connection may well become unequivocally "proven," it is highly possible that the runaway will have already been triggered and therefore too late to stop. 

There will be no chance for a do-over here. For those who advocated complacency and were wrong, there will not be an opportunity to reverse courseWith all respect, I must ask Archer why he would advocate a position that could have such unspeakably tragic consequences?  The incomparably more relevant question to ask is whether the factors may be lining up that could bring on a runaway, and what our societal response should be if they are. 

5)  Amplification and Other Consequences of Complacency  

We are obviously in a situation where time is of the essence. There are also two other factors that come into play. Huge amounts of fossil fuel industry money are backing orchestrated efforts to discredit climate science in general and most certainly any sense of urgency. In addition, many people are struggling with a very natural form of psychological denial that blocks us from seeing how close humanity may be to oblivion. 

I have no reason at all to doubt the sincerity of Archer and believe his stance to be genuine. But when a scientist on a blog as respected as RealClimate downplays urgency, it can inadvertently be used as fodder to support both of these factors. Such a stance can be amplified by the blog universe (e.g., at Scientific American, as well as many denialist sites)  to give an impression of a "consensus" in the scientific community when this is emphatically not the case. 

Archer is delivering a message of complacency (what Joe Romm refers to as "pushing the snooze button" [23]) at precisely the moment when humanity must be heightening its vigilance to avoid passing a point of no return. I sincerely state that nothing personal is intended, but from the standpoint of human survival I must respectfully ask Archer whether such a stance might not be justifiably characterized as irresponsible? I cannot believe that he would choose to occupy the position of being a scientist who contributed to a complacency which blunted expression of legitimate concern and the actions which might have prevented a catastrophe.  

6)  The Case for Invoking the Precautionary Principle and Assigning All Resources Necessary to Confirm Whether A Runaway Situation Is Being Approached 

A methane runaway would qualify as a planetary emergency. It is the view of a growing network of concern that several factors are combining which point toward the near term potential for such to develop in the Arctic. Rather than discredit such concern, humanity would be much better served by a rigorous scientific inquiry that could confirm whether there is merit to it. Igor Semiletov, involved in cutting edge field research on methane emissions, has informed this writer that much more could be accomplished with expanded funding support.

I call upon Archer and all RealClimate contributors to vocally support an immediate and high-level escalation of research aimed toward "getting at the facts" on potential runaway -- no matter where they lead.  As the stakes could not be higher, it would be unspeakably tragic if world governments failed to provide such and the situation evolved to a point where a catastrophe spun out of control.  

Preparation of Safe Geo-Engineering Options Should Humanity Need to Use Them 

The concept of geo-engineering has attracted a spectrum of opinions ranging from support to opposition and many shades in between. However, there is a fundamental reality staring in our face. If humanity waits until the point of no return is crossed and a runaway is unleashed, it will be too late to develop any such options. In the opinion of this writer, the prudent position is to work now on developing safe geo-engineering options so that there might at least be a chance to implement them should the world become convinced that a runaway is imminent.    

Perceiving a threat that Arctic ice could conceivably collapse as soon as 2013, John Nissen  (chairperson of the Arctic Methane Emergency Group) [24] offers a statement in support of urgent development of safe modes of geo-engineering:

The Arctic Methane Emergency Group (AMEG) has been set up for the express purpose of drawing the world’s attention to the danger arising from astonishingly rapid retreat of sea ice, accelerated warming of the Arctic and escalating methane emissions from the seabed, especially in the area off the Siberian coast. It is the methane that can produce abrupt climate change, but it is the retreat of sea ice that has triggered this crisis... We are approaching a likely point of no return, and therefore it is essential that emergency measures are taken to avoid passing this point. This involves intervention on a large scale to cool the Arctic, either directly or indirectly by cooling currents and rivers flowing into the Arctic. By definition such intervention constitutes what is called 'geoengineering,' but, whereas geoengineering has generally been considered on a global scale to counter global warming rising over decades, we need geoengineering geared to cool the Arctic with a timescale of just months, to prevent a possible collapse in sea ice extent in September 2013.

Critical Need for the Scientific Community to Speak Out More Forcefully
In the case of methane, we are not dealing with a dramatic image of an atomic fireball and its capacity to render immediate destruction. But extended over a longer range of time, the global devastation it would inflict would be no less sweeping. The spectre of a methane runaway is real and it is an existential threat to humanity.

In our society, the scientific community holds a position of great respect. In order to protect scientific "objectivity," our tradition has been to separate the institution of science from the realm of public policy. I do not call upon RealClimate to violate its internal agreement and issue specific policy directives. However, I do call upon it to release a generic warning to policy makers that humanity must break out of its state of denial, recognize that the laws of physics do not operate on a political calendar, realize we are dealing with a powerful force that can spin out of control, and therefore quickly educate ourselves as to the severity of the threat. It is my hope that RealClimate -- as well as the larger community of climate scientists -- will rise to the occasion and show the way.     

- by Gary Houser, co-producer and writer of the documentary film "Sleeping Giant of the Arctic: Could Thawing Methane Trigger Runaway Global Warming?"  


[1]  UK Independent, December 13, 2011. Vast methane 'plumes' seen in Arctic ocean as sea ice retreats ... 
[7] Documentary interview with Leifer (in progress); the crew has interviewed climate scientists Igor Semiletov and Natalia Shakhova (International Arctic Research Center (IARC) at the University of Alaska-Fairbanks), Ira Leifer (Marine Science Institute at University of California-Santa Barbara), Vladimir Romanovsky (IARC), and Katey Walter (University of Alaska-Fairbanks). On geological history and extinction events, paleo-climatologists Michael Benton (University of Bristol, U.K., author of the book When Life Nearly Died), and Andrew Glikson (Australian National University, Canberra). Also in consultation with Peter Wadhams of the University of Cambridge -- one of the top Arctic ice experts in the U.K. 
[10]  Interview segment with James Hansen:   
[11] from Hansen's book Storms of My Grandchildren
[12] Documentary interview with Semiletov: 
[19] Documentary interview with Semiletov: 
[24] Arctic Methane Emergency Group (AMEG) website:


Peter said...

There are three important omissions in this response.

Firstly, the predicted Arctic warming, quoted as up to 20F (11 degrees C) is the warming at the surface. Water is a good thermal insulator, as is the sediment overlying the deposits, so it's by no means certain that the methane deposits will "see" the same amount of warming.

Secondly, although that amount of warming is predicted, it mostly hasn't happened yet. Current warming of these areas amounts to something like a couple of degrees C averaged over the year. That's significant and worrying, of course, but we need to be accurate!

Thirdly, warming caused by our CO2 emissions has to be seen in the right context. The East Siberian Arctic Shelf was above water during the ice age due to lower global sea levels. As such, the average temperature was tens of degrees below freezing at the time the permafrost deposits formed. When the shelf was inundated at the end of the Ice Age as sea levels rose, this permafrost saw a jump in temperature levels of something like 20 degrees C or more. This is VASTLY GREATER than any current signal of anthropogenic warming, and double the worst-case scenario for future warming.

Simply put, the methane activity observed by Semiletov, Shakahova and others is very unlikely to be due to anthropogenic causes. Rather, it is due to the post-glacial inundation of frozen tundra, which produces local warming far greater than any current or predicted effect of anthropogenic emissions. They have always been very clear about this. If the "clathrate gun" or "methane time bomb" is indeed going off as we speak, it doesn't have anything to do with us. Despite our worst efforts, anthropogenic warming of the methane deposits is negligible in context.

Of course, worries still remain for the future: even though humanity's effects on warming these deposits are small in context, obviously we should add as little as possible extra heat into the equation. However, the fact that the "clathrate gun" hasn't gone off at the end of previous ice ages does tend to suggest that in aggregate these deposits are more stable than feared.

Tenney Naumer said...

Hi Peter,

Thanks for your comment.

I am still perplexed as to why the methane is increasing so rapidly in the air above the Arctic.

Why would the methane hydrates have remained frozen during other periods of warm temperatures during the last several thousand years? Why didn't they melt then? There is a missing element that has not been explained yet.

One reason may be the rapid shift in the jet stream to the north. Perhaps this did not occur during the prior warm periods because the warming back then was so gradual.

I dunno....

Peter said...

Well, there will probably be increased methane production from the land adjacent to the Arctic. Also, perhaps increased methane production from bacteria in the ocean itself, which is quite a distinct process from melting of subsea deposits. I remember reading somewhere (can't locate the ref, sorry) that summer/fall methane levels were elevated across the entire Arctic: the deep bits as well as the shallow shelves. This lends credence to the idea that it's processes in the surface water that are at play, rather than the subsea layer.