THE TRAGIC FAILURE OF THE SCIENTIFIC COMMUNITY TO ISSUE ADEQUATE WARNING RE: THE ARCTIC TIPPING POINT EMERGENCY

by Gary Houser

"Our greatest concern is that loss of Arctic sea ice creates a grave threat of passing two other tipping points -- the potential instability of the Greenland ice sheet and methane hydrates. These latter two tipping points would have consequences that are practically irreversible on time scales of relevance to humanity." [1]  ....."We are in a planetary emergency." [2] - World renowned climate scientist Dr. James Hansen

The scientific community must be commended for its efforts to convey to the world the reality of climate disruption caused by carbon dioxide (CO2) emissions. That world is now grappling with the politics of whether effective reductions can be achieved in time. But there appears to be a new danger emerging from the Arctic which threatens to accelerate such disruption beyond the reach of any meaningful control. Cutting edge researchers in the field are observing large plumes of methane rising from the shallow seabeds. [3] Others are discovering heightened levels through airborne measurement. [4]  According to the most recent Intergovernmental Panel on Climate Change (IPCC) report, methane is a global warming gas no less than 72 times more powerful than CO2. [5]

In the course of working on a documentary [6] on this super greenhouse gas and the frightening prospect that such is beginning to thaw and release to the atmosphere in the Arctic, the author has encountered a highly disturbing "disconnect". On the one hand, there are highly eminent scientists - such as James Hansen - warning that the situation in the Arctic could well lead to the crossing of an "irreversible tipping point". On the other hand, such warning is not finding its way into the major scientific reports which government policy makers will use to chart their response. It cannot be found in either the draft of the new IPCC report or the draft of the U.S. National Climate Assessment.

As global climate disruption begins to enter the realm of "tipping points of no return", humanity is coming face to face with a moral crisis inextricably linked to the physical crisis. Scientists are first and foremost human beings. If information is discovered that points to a real possibility that a given situation can abruptly escalate into an existential threat to human survival, there is a profound moral responsibility to issue a loud and unambiguous warning.

There are now several indicators that the factors which could generate such a threat are indeed lining up in the Arctic - such as the ice collapse and the loss of solar reflectivity that will only accelerate further Arctic warming. At this time however, other than a handful of notable exceptions, the scientific community as a whole is utterly failing to issue such warning. This essay is an attempt to grapple with what might be the systemic reasons for such failure. Although the author is not a scientist and addresses the issue from outside that frame of reference, reasons are provided for why such may be an advantage rather than a disadvantage.

The climate science community around the world is performing a tremendous service to humanity. As climate disruption continues to escalate and the threat to our society becomes more grave, its members have worked long hours - in many cases on their own time - to gather the relevant data. As only one example. documentary-related exchanges between the author and scientists working in the Arctic make clear that much personal hardship and sacrifice are being endured in order to conduct such research.

It is well known that in preparation for their work, scientists are taught to exercise great caution in reporting their findings and never stray beyond that for which there is incontrovertible evidence. Even when it appears evidence is present, it is the time-honored tradition of science to still submit any conclusions drawn from such to their peers for review.

In almost every case, this strict methodology has well served the public interest. It has filtered out errors and made solid information available to the public and policy makers. But in the arena of global climate disruption, humanity is now facing something unique and quite un-paralleled by any other issue. There is a point in the process of climate de-stabilization where colossal natural forces can be unleashed which are capable of developing their own unstoppable momentum and spiralling well beyond the reach of human control. When such occurs - the already mentioned "irreversible tipping point".

Though a term used frequently in discussions on climate, its full meaning and magnitude have rarely been taken to heart. Far too often, it is simply another "buzzword" dropped into an article and treated only in the most superficial way. Indeed, such usage seems almost to "anesthetize" us to the horrific reality it points toward. In truth, the crossing of some kinds of tipping points can lead to the crushing of our entire civilization on no less of a scale than nuclear war. The devastation can be so sweeping that the concept of "adaptation" becomes meaningless. "Irreversible" refers to the brutal fact that once humanity allows this process to become triggered, there will be no chance to go back, no chance to learn from our mistakes and correct them.

Of the several tipping point scenarios which are possible, one considered especially frightening is the prospect of triggering an abrupt and large scale methane release in the shallow seabeds along Arctic coastlines. The entire climate debate has been dominated by a discussion of humanity's contribution to the problem - which has been the emission of carbon dioxide since the beginning of the industrial age. What science has discovered is that nature has its own vast storehouse of ancient carbon trapped in the ice of the polar regions.

The scenario of most concern to methane "specialists" is what's known as the "runaway feedback" reaction. As described by Dr. Ira Leifer of the Marine Science Institute at the Univ. of Calif.: "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]  A cycle would be initiated which feeds upon itself and therefore becomes unstoppable.

When one looks at the history of the most devastating "wipeouts" of life on earth - such mass extinction events as the PETM or the end-Permian - it is sobering to learn that large scale release of methane has been pointed to as a "probable cause". World-renowned climate science pioneer Dr. James Hansen relates methane to the PETM extinction event:

"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." [8]

The end-Permian extinction was the most colossal mass extinction event, wiping out over 90% of the life forms on earth. According to paleontologist Michael Benton - considered by some to have written the definitive book on this event (When Life Nearly Died):

"Normally, long-term global processes act to bring greenhouse gas levels down. This kind of negative feedback keeps the Earth in equilibrium. But what happens if the release of methane is so huge and fast that normal feedback processes are overwhelmed? Then you have a "runaway greenhouse"...... As temperatures rise, species start to go extinct. Plants and plankton die off and oxygen levels plummet. This is what seems to have happened 251 million years ago." [9]

While devastation on this level is inherently difficult to grasp, one attempt to convey such is provided in the documentary "Miracle Planet". [10] Though absolute certainty on causation may not be attainable, just the possibility that our society may be triggering a force with this kind of power is mind-boggling enough.

Could anything of this unspeakable magnitude be triggered by thawing methane in the Arctic? Again Ira Leifer: "The amount of methane that’s trapped under the permafrost and in hydrates in the Arctic areas is so large that if it was rapidly released it could radically change the atmosphere in a way that would be probably unstoppable and inimicable to human life." [11]  Hansen adds: "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." [12]  Dr. Hansen - along with Arctic ice and methane experts - address this issue in more depth in a documentary co-produced by the author. [13]

Methane plumes rising from the seafloor

In examining the key reports being made by the scientific community - such as drafts for the new IPCC document and the National Climate Assessment (of the U.S.), one might expect there to be dire warnings about a potential "point of no return" if these forces are unleashed. We do find a discussion of the various consequences of climate disruption that are hitting right now - Arctic and glacial melt, extreme weather, more powerful hurricanes and storms, increases in drought, food shortages, wildfires, and flooding. But where is the discussion of what these symptoms of disruption are leading to? One of the most frightening spectres looming over humanity - the tipping point of a methane "runaway" - is completely ignored.

How can this be possible? Several factors may be combining. As stated earlier, scientists are trained to only make statements based on "hard evidence". In the case of a potentially abrupt methane runaway, it is not possible to pinpoint a specific moment in time when such may be initiated. It cannot be stated with certainty whether this will happen in 2017, 2027, or 2037. Without this ability to pinpoint and quantify, the response of science has been to simply not address it.

Secondly, scientists are human. All of us have great difficulty in truly facing and absorbing the full implications of a complete collapse of human society and even a wiping out of most or all life on the planet. It is human to utilize methods of psychological denial to block out such a staggeringly horrific threat to our collective existence. In this instance, scientists are no different. Unless there is "absolute proof" staring us in the face, the overwhelming tendency is to push such thoughts out of our consciousness so we can "get on with our day".

A third factor is that the current methodology for the reporting of climate science is fundamentally flawed and dysfunctional in regard to the challenge at hand. The single most important such report is that issued by the Intergovernmental Panel on Climate Change (IPCC). It is based on a consensus process and an intensively time-consuming level of peer review. Under normal circumstances, such would be seen as positives. But in a situation where humanity may come under severe threat in the very near term future, these reports are essentially looking backward at where science has been for the past 7 years rather than reporting the cutting edge trend lines. A glaring example is how the IPCC completely missed on predicting the speed at which the Arctic would melt.

The tremendous danger with this situation is that by the time any kind of "absolute proof" is gathered, it will very likely be too late to stop the conditions bringing on the dreaded runaway reaction. An unspeakably terrifying process will already have been set into motion and humanity at that point will be helpless to stop it. Temperatures on earth could eventually skyrocket to a level where mass famine is initiated.

What are the potential solutions to these terrible problems? One would be procedural. A special section of such reports should be dedicated to communicating the work of those scientists whose research is on the cutting edge of dealing with potentially huge climate impacts and yet still "in progress" in terms of gathering the relevant data. For example, even though the precise timing of a methane runaway cannot be predicted, there should be a report on the trend lines and the extent to which the conditions that could bring on a runaway are manifesting. If those conditions are lining up to a considerable extent, then an appropriate warning should be issued.

A second corrective step is more related to basic philosophy and morality. At the Earth Summit in Rio in 1992, representatives of the world's nations agreed to apply the precautionary principle in determining whether an action should go forward to prevent irreversible damage to the environment. Principle #15 of the Rio Declaration [14] states that:

"In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation."

In a further treatment of the meaning of the precautionary principle, it has been stated that there must be

"a willingness to take action in advance of scientific proof of evidence of the need for the proposed action on the grounds that further delay will prove ultimately most costly to society and nature, and, in the longer term, selfish and unfair to future generations." [15]

A methane runaway in the Arctic more than meets the criteria of being a "threat" which can bring about "irreversible damage". Due to its potential to create an unstoppable wave of continually rising temperatures capable of initiating something as horrendous as a mass extinction event, its irreversible damage could be of the most frightening magnitude imaginable. If humanity failed to recognize this danger and allowed its occurrence, such would most certainly constitute an irreparable crime against future generations. The most fundamental tenet of human morality demands that in such a unique situation the scientific community act on the basis of the precautionary principle and issue the appropriate warning.

In his powerful book on the ethics of nuclear war, Jonathan Schell wrote: "To kill a human being is murder, but what crime is it to cancel the numberless multitude of unconceived people?" [16] In the words of the ecological ethicist David Orr: "Climate destabilization, like nuclear war, has the potential to destroy all human life on Earth and in effect 'murder the future'......... Willfully caused extinction is a crime that as yet has no name." [17]

Is it possible that the very pillar of science which has served our society so well - the uncompromising demand for incontrovertible "evidence" - has in this unprecedented current crisis become a dangerous obstruction? Is it possible that this requirement of absolute "proof" is creating a perceptual blindness that could pave the way for the most horrendous suffering in the history of civilization?

To the scientists who may read this essay, an appeal is made in the name of our collective humanity to truly confront and grapple with the meaning of the term "irreversible" and weigh the potentially horrific consequences of silence. It is no violation of scientific "objectivity" to look at trend lines and determine whether their continued trajectory might well carry our civilization over the cliff. And if this possibility is there, is there not a profound moral obligation under the precautionary principle to issue a loud and unambiguous warning to humanity?

Before arriving at an answer, the reader - and especially any member of the scientific community - is invited to view a powerful film that is simply entitled "HOME". [18] In this artistic masterpiece, images of life on earth convey beyond the reach of words the incredible magnificence of what will be lost if climate disruption is allowed to escalate into an unstoppable "wipe-out". It also describes the methane lurking in the Arctic as a "climatic time bomb". Please watch and please speak out before it is too late. As James Hansen says: "We are in a planetary emergency."

LINKS

[1] Bloomberg, August 17, 2012
[2] AFP: 'Planetary emergency' due to Arctic melt, experts warn
[3] Vast methane 'plumes' seen in Arctic ocean as ... - The Independent
[4] Danger from the deep: New climate threat as methane rises from ...
[5] www.ipcc.ch/publications_and_data/ar4/wg1/en/tssts-2-5.html
[6] [Documentary co-produced by author]: Arctic News: Arctic methane: Why the sea ice matters
[7] Interview with Leifer for documentary
[8] Interview with Hansen http://youtu.be/ACHLayfA6_4
[9] Wipeout: the end-Permian mass extinction
[10] 6 minute clip from "Miracle Planet": http://youtu.be/exfNNDExxIc
[11] Interview with Leifer for documentary
[12] Hansen's book: Storms of My Grandchildren: The Truth About the Coming Climate ...
[13] Same as link at #6
[14] Rio Declaration
[15] www.dieoff.org/page31.htm
[16] The Fate of the Earth - The New York Times
[17] Thinking About the Unthinkable by David Orr We ... - Moral Ground
[18] [Link to free full film]: http://www.youtube.com/watch?v=jqxENMKaeCU

'Rising to Meet the Tide': A Letter to Obama on Climate Change

Gary Houser, long-time public interest writer, documentary
producer currently working on climate tipping points, and
member of the Arctic Methane Emergency Group (AMEG),
with one of his projects, solar parking for Athens, Ohio.

by Gary Houser

"The threat from climate change is serious, it is urgent, and it is growing. Our generation's response to this challenge will be judged by history, for if we fail to meet it – boldly, swiftly, and together – we risk consigning future generations to an irreversible catastrophe... the time we have to reverse this tide is running out."

—President Obama's speech to the UN in 2009

"There are potential irreversible effects of melting the sea ice... We'll begin to release methane hydrates... There is enough there to cause as much warming as all the coal in the world... It's not clear that civilization could survive that extreme climate change."

 —Dr. James Hansen, renowned climate scientist. (interview for documentary "Arctic Methane Tipping Point?" )

Dear President Obama,

History has conspired to place you at the presidential helm during a turning point moment of unprecedented global significance. The climate crisis preceded your presidency and will still be with us when it ends. But time is quickly running out to prevent this crisis from escalating beyond human control. The staggering record loss of Arctic ice seen this year is a clear sign that the forces of climate change have been set in motion. A growing chorus of scientists and experts believe we are sitting on the knife's edge of  humanity's ability to mitigate or stop the growing threat.

When you chose to open your presidential campaign in Springfield, Illinois in 2008, you made a bold statement about your aspirations to the greatness of an Abraham Lincoln. The mark of a great president is to recognize the moral issue that transcends all others and take the actions which push history in a positive direction. Lincoln did so on the issue of slavery. In a speech to Congress in 1862, he said: "The dogmas of the quiet past are inadequate to the stormy present. The occasion is piled high with difficulty and we must rise with the occasion. As our case is new, so we must think anew and act anew."

The call that beckons you is to recognize the unique, all-encompassing urgency associated with the need to prevent a global climate catastrophe. There is no higher mission you could possibly perform than to "rise to the occasion" by using your oratorical gifts to inspire humanity to turn back from the brink of oblivion.

While world attention has focused on human-generated carbon dioxide, a sleeping giant has been stirring in the Arctic. Frozen methane is thawing and releasing a global warming gas at least 30 times more powerful than CO2. There is more carbon energy in this methane than all the world's reserves of coal, oil, and natural gas combined. As both open water and methane push Arctic temperatures higher, even more methane is subject to thawing and release—creating the frightening prospect of an unstoppable "runaway" chain reaction, or feedback loop. In a frightening worst case scenario, the planet could be pressed toward a mass extinction event comparable to earlier ones that some scientists attribute (video) to large scale methane release.

In your 2009 speech to the UN you shared these uplifting words: "It is work that will not be easy... But difficulty is no excuse for complacency. Unease is no excuse for inaction... It is a journey that will require each of us to persevere through setback, and fight for every inch of progress."

It is clear why every single "inch of progress" has become a "fight". Though the survival of life on earth surely transcends partisan politics, a fossil fuel industry blinded and rendered senseless by corporate bottomlines has invested mountains of money to attack climate science and confuse the public. Are you willing to "persevere through setback" and speak truthfully by exposing these actions as nothing less than crimes against current and future generations?

History shows that the American people have responded positively to presidents who courageously took the moral high ground in response to soul-testing adversity. Seize your greatness as a president and the people will honor you. Polls show that a majority of the independent voters that campaign strategists say you need are actually with you on climate.

The decision that will be—in your own words—"judged by history" is in your hands. Will you act on behalf of our children and future generations before the "time to reverse the tide runs out"? The moment has come to end the silence.

In your 2008 campaign, you featured these words from Rev. Martin Luther King: "We are confronted with the fierce urgency of now."

However, you did not mention the warning that immediately followed, when King said: "There is such a thing as being too late... We may cry out desperately for time to pause in her passage, but time is deaf to every plea and rushes on. Over the bleached bones and jumbled residue of numerous civilizations are written the pathetic words: 'Too late.'"

Posted with author's permission - earlier posted at commondreams.org

Rebuttal: Imminent collapse of Arctic sea ice drives danger of accelerated methane thaw

REBUTTAL:

         IMMINENT COLLAPSE OF ARCTIC SEA ICE DRIVES DANGER OF ACCELERATED METHANE THAW:

         Archer Errs in Dismissing Concern About Potential "Runaway" Feedback, Precautionary Principle Should Prevail  

by Professor Peter Wadhams

Image: Methane bubbles from: Sauter et al. dx.doi.org/10.1016/j.epsl.2006.01.041 

Background of rebuttal author -
Peter Wadhams Sc.D. is Professor of Ocean Physics at the University of Cambridge in the UK. He is an oceanographer and glaciologist involved in polar oceanographic and sea ice research and concerned with climate change processes in the polar regions He leads the Polar Ocean Physics group studying the effects of global warming on sea ice, icebergs and the polar oceans. This involves work in the Arctic and Antarctic from nuclear submarines, autonomous underwater vehicles (AUVs), icebreakers, aircraft and drifting ice camps. He has led over 40 polar field expeditions. His full background is available here: University of Cambridge DAMTP: Professor Peter Wadhams

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In a Jan. 4 post on "Real Climate" (1), David Archer addressed those who are raising concern about the speed of ice loss in the Arctic and the resultant potential for warming water temperatures to thaw frozen methane and release it as gas to the atmosphere. In essence, he dismissed such concern as a form of unfounded alarmism making "much ado about nothing". In this rebuttal, I would like to respectfully challenge this dismissive stance and assert that severe dangers are arising in the Arctic which instead call for the full attention of humanity.

The present thinning and retreat of Arctic sea ice is one of the most serious geophysical consequences of global warming and is causing a major change to the face of our planet. A challenging characteristic of the behaviour is that both the rate of retreat (especially in summer) and the rate of thinning in all seasons have greatly exceeded the predictions of most models. The sea ice cover of the Arctic Ocean, particularly in summer, has been in retreat since the 1950s at a rate of about 4% per decade which has recently increased to 10% per decade. More seriously, the thickness of the ice has diminished.

Satellites can track ice area, but ice thickness distribution can be most accurately measured by sonar from underneath the ice. Since 1971, I have been going to the Arctic in UK nuclear submarines, mapping the ice thickness using upward-looking sonar along the vessel’s track. U.S. submarines have also allowed such availablity. Opening these submarines to scientific work has been a marvelous service to climate research. It was thanks to submarines that I was able to show for the first time that the ice in the Arctic is thinning (in a 1990 paper in Nature (2), showing a 15% thickness loss in 11 years), and recent work from UK and US submarines now shows a loss of more than 43% in thickness between the 1970s and 2000s, averaged over the ocean as a whole (3). This is an enormous loss – nearly half of the ice thickness – and has changed the whole appearance of the ice cover. Most of the ice is now first-year rather than the formidable multi-year ice which used to prevail.

The thinning is caused by a mixture of reduced growth in winter, because of warmer temperatures and more heat in the underlying water column, and greater melt in summer. A change in the direction and speed of ice motion has also played a role, with the ice departing quicker from the Arctic Basin through Fram Strait rather than circulating many times inside the Arctic.

The summer (September) area of sea ice reached a record low in 2007, almost matched in 2011, but what is most serious is that the thinning continues. It is inevitable that very soon there will be a downward collapse of the summer area because the ice will just melt away. Already in 2007, measurements indicated that during the summer there were 2 metres of melt off the bottom of of ice floes in the Beaufort Sea, while the neighbouring first-year floes had only reached in 1.8 metres during winter – so all first-year ice was disappearing. This effect will become more important and will spread throughout the Arctic Basin.

There is currently disagreement about when the summer Arctic will become completely ice-free. It depends on what model is being employed. My own view is based on purely empirical grounds, that is, matching the observations of area from satellites with observations from submarines (combined with some modelling) of thickness to give us ice volume. If we think in volume terms instead of area terms, the downward trend is more than linear, in fact it is exponential, and if extrapolated it gives us an ice-free summer Arctic as early as 2015.

Others have talked of later dates, like 2030-2040, but I do not see how the trend of summer ice volume can possible permit this. Those who agree include W Maslowsky, a leading ice modeller (Naval Postgraduate School, Monterey), and the PIOMAS project at University of Washington which generated the data shown below (4).

Arctic sea ice volume decline graph by Wipneus based on PIOMAS data. 

Minimum volume of Arctic sea ice in midsummer, based on areas observed from satellites and thickness trends inferred from submarine observations. Extrapolation leads to a zero volume in 2015. It must be pointed out that this perspective stands in direct contradiction to very complacent statements about the Arctic sea ice from the IPCC in the AR4 report of April 2007 saying the sea ice was very likely to last beyond the end of the century.

The ice retreat is having major impact on the planet. The Arctic is the most rapidly warming region on Earth. It has become widely accepted that Arctic amplification of global warming is due to the albedo effect of sea ice retreat. The increased open water reduces the albedo (fraction of solar radiation reflected into space) and causes warming at high northern latitudes to be 2-4 times as fast as in the tropics, with enormous implications for climatic instability. Secondly, the summer retreat of the ice from the wide Arctic continental shelves (particularly the East Siberian Sea) allows the shallow surface layer to warm up, bringing temperatures of up to 5 degrees C right down to the seabed.

Quantification of this affect has only very recently been attempted, in a paper to the 2011 AGU by Hudson (5). The startling conclusion is that the rate of warming of the Arctic could double or triple, once the Arctic Ocean is ice-free in September. And it could double or triple again, once the ocean is ice-free for half the year. But the timescale makes this all the more worrying.

The scientific community has drawn attention to the risk of dangerous climate change if the world does not reduce emissions of carbon dioxide - a worthy and critical objective. However, I wish to point toward a much more immediate problem that does not seem to be recognised among the climate change community at large: This is the problem of rapid retreat of Arctic sea ice, and likely consequence of catastrophic methane feedback.

These rapidly warming temperatures are accelerating the melt of offshore permafrost, releasing methane trapped as methane hydrates and causing large plumes of methane to appear all over the summer Arctic shelves (observed for the last 2-3 summers by Semiletov and colleagues on joint University of Alaska – Far Eastern Research Institute cruises). Methane levels in the Arctic atmosphere have started to rise (measured by Dr Leonid Yurganov, Johns Hopkins University) after being stable for some years. As methane is a very powerful, if short lived, greenhouse gas, this will give a strong upward kick to global warming.

According to research crew leader Igor Semiletov:

"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." (6)

Semiletov has also described how warmer temperatures are making their way down to the bottom of the shallow seabeds in the Arctic continental shelves:

"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). As this warming spreads to a larger area, the more that shelf-based permafrost will thaw." (7)

There have been warnings that a major methane outbreak may be imminent.

In a piece Archer co-authored in 2009, he acknowledged both the significant warming 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." (8)

In this same piece, Archer affirms another key factor:

"Rapid warming well above the global average makes the Arctic hydrates particularly vulnerable to climate change." (8)

Archer clearly acknowledges the vulnerability of methane hydrates to thawing in response to rising Arctic temperatures. Given that ice loss is accelerating, which in turn will only accelerate that temperature rise through the albedo effect, one has to wonder why he does not perceive an imminent and urgent crisis. Ira Leifer - methane specialist at the Marine Science Institute at Univ. of Calif - Santa Barbara - describes the mechanics of a "runaway" methane feedback:

"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." (9)

Given that this "train" would be one way and feed upon itself in a way that might well be unstoppable by humanity, it would seem to be a classic case where the precautionary principle should immediately be invoked. When Archer dismisses the legitimate concern that conditions in the Arctic are approaching a potentially catastrophic tipping point, he is deflecting away a vitally important perspective that needs to be communicated to the world's policymakers. I strongly urge Archer to re-consider his position.

It is also my understanding that one of the recipients of Archer's "dismissal" charge was documentary film-maker Gary Houser. Houser had submitted an earlier rebuttal to Archer - based on his interviews with scientists related to a program on the issue of Arctic methane - which was rejected by "Real Climate" on the grounds that he himself is not an accredited scientist. I have read his rebuttal and wish to link to it here (10), as I believe it contains points of merit I do not have space to address here.

Footnoted sources and links:
(1) RealClimate: Much ado about methane
(2) Wadhams: 1990 Wadhams, P. Evidence for thinning of the Arctic ice cover north of Greenland. Nature, Lond., vol 345, 795-797.
(3) Wadhams: Arctic Sea Ice Thickness: Past, Present & Future - European ...
(4) PIOMAS graph link: http://neven1.typepad.com/.a/6a0133f03a1e37970b0153920ddd12970b-pi
(5) Hudson: http://www.agu.org/pubs/crossref/2011/2011JD015804.shtml
(6) UK Independent, Dec.13, 2011 Vast methane 'plumes' seen in Arctic ocean as sea ice retreats ...
(7) Documentary interview with Semiletov: www.590films.org/methane.html
(8) Archer, co-author Gas hydrates: entrance to a methane age or climate ... - IOPscience
(9) Documentary interview with Leifer: www.590films.org/methane.html
(10) Houser rebuttal to Archer, link: http://arctic-news.blogspot.com/2012/02/rebuttal-david-archer-wrong-to-dismiss.html

Professor Peter Wadhams is author of a recent science paper entitled "Arctic Ice Cover, Ice Thickness, and Tipping Points". It was published in AMBIO: A Journal of the Human Environment produced by the Royal Swedish Academy of Sciences. Link to abstract and full text preview of published article: Arctic Ice Cover, Ice Thickness and Tipping Points - SpringerLink This paper was written for the Arctic Tipping Points Project (www.eu-atp.org) - a large scale integrating project funded by the European Union 7th Framework Programme.

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