Expedition to study methane gas bubbling out of the Arctic seafloor

The black rectangle on this map shows the general region
where Paull and his collaborators have been studying
methane releases in the Beaufort Sea. The smaller red
rectangle indicates the edge of the continental shelf and
continental slope where they will conduct research during t
heir current expedition. These areas are shown in greater
detail in the maps below. Base image: Google Maps

Chasing gas bubbles in the Beaufort Sea

In the remote, ice-shrouded Beaufort Sea, methane (the main component of natural gas) has been bubbling out of the seafloor for thousands of years. MBARI geologist Charlie Paull and his colleagues at the Geological Survey of Canada are trying to figure out where this gas is coming from, how fast it is bubbling out of the sediments, and how it affects the shape and stability of the seafloor. Although Paull has been studying this phenomenon for a decade, his research has taken on new urgency in recent years, as the area is being eyed for oil and gas exploration.

In late September 2012, Paull and his fellow researchers will spend two weeks in the Beaufort Sea on board the Canadian Coast Guard ship Sir Wilfred Laurier, collecting seafloor sediment, mapping the seafloor using sonar, installing an instrument that will "listen" for undersea gas releases, and using a brand new undersea robot to observe seafloor features and collect gas samples.

This will be Paull's third Beaufort Sea expedition. As in previous expeditions, he will be working closely with Scott Dallimore of Natural Resources Canada's Geological Survey of Canada and Humfrey Melling of Fisheries and Oceans Canada's Institute of Ocean Sciences.

Paull's work in the Arctic started in 2003, with an investigation into the enigmatic underwater hills called "pingo-like features" (PLFs) that rise out of the continental shelf of the Beaufort Sea. (Pingos are isolated conical hills found on land in some parts of the Arctic and subarctic.)

Over time, the focus of the team's research has moved farther offshore, into deeper water. Their second expedition in 2010 looked at diffuse gas venting along the seaward edge of the continental shelf. The 2012 expedition will focus on three large gas-venting structures on the continental slope, at depths of 290 to 790 meters (950 to 2,600 feet).

This idealized cross section of the continental shelf and
continental slope in the Beaufort Sea shows zones in the
seafloor where permafrost and methane hydrate are
likely to exist, as well as hypothetical locations of methane
seeps on the seafloor. Ocean depths not shown to scale.
Image: © 2012 MBARI

Frozen gas—a relict of previous ice ages

The Beaufort Sea, north of Canada's Yukon and Northwest Territories, is a hostile environment by any definition of the term. It is covered with ice for much of the year. Historically, only from mid-July to October has a narrow strip of open water appeared within about 50 to 100 kilometers (30 to 60 miles) of the coast. Even at this time of year, winds often howl at 40 knots and temperatures can drop well below freezing at night. Researchers must allow extra time for contingencies such dodging pack ice and having to shovel snow off the deck of the research vessel.

Average annual air temperatures along the coast of the Beaufort Sea are well below freezing. Thus deeper soils remain permanently frozen throughout the year, forming what is called permafrost. Around the Beaufort Sea, permafrost extends more than 600 meters (about 2,000 feet) below the ground.

Permafrost also exists in the sediments underlying the continental shelf of Beaufort Sea. This permafrost is a relict of the last ice age, when sea level was as much as 120 meters lower than today. At that time, areas that are now covered with seawater were exposed to the frigid Arctic air.

As sea-level rose over the last 10,000 years, it flooded the continental shelf with seawater. Although the water in the Beaufort Sea is cold—about minus 1.5 degrees Centigrade—it is still much warmer than the air, which averages minus 15 degrees C. Thus, as the ocean rose, it is gradually warmed up the permafrost beneath the continental shelf, causing it to melt.

Quite a bit of methane, the main component of "natural gas," is trapped within the permafrost. As the permafrost melts, it releases this methane, which may seep up through the sediments and into the overlying ocean water.

The deeper sediments of the Beaufort Sea also contain abundant layers of methane hydrate—an ice-like mixture of water and natural gas. As the seafloor has warmed, these hydrates have also begun to decompose, releasing additional methane gas into the surrounding sediment.

These maps show the area to be studied during the
current expedition. The lower map shows the continental
shelf and continental slope of the Beaufort Sea. The
upper image shows detailed seafloor bathymetry of a
portion of the continental slope that will be studied
during the current cruise, as well as the three seafloor
mounds that the researchers will explore using their
new ROV. Lower image modified from Google Maps.
Upper image: Natural Resources Canada.

A tantalizing glimpse

A 2010 expedition by Paull and his colleagues provided a tantalizing glimpse of how much methane is present on the continental shelf of the Beaufort Sea. Using a remotely operated vehicle (ROV) with video camera to explore the shelf edge, they found white mats of methane-loving bacteria almost everywhere. They also videotaped what turned out to be methane bubbles emerging from many of these mats. Based on these observations, as well as the contents of sediment cores collected by the Geological Survey of Canada, the researchers concluded that the shelf edge is an area of "widespread diffuse venting" and that "methane permeates the shelf edge sediments in this region."

During 2010, the research team also conducted ROV dives on a shallow underwater mound called Kopanoar PLF. At the top of this mound they discovered "vigorous and continuous gas venting" that released clouds of bubbles and sediment into the water. In one ROV dive, the researchers saw something no one had ever seen before—a plume of gas bubbles that moved rapidly along the sea floor, apparently following a crack in the sediment that was in the process of being forced open by the pressure of the gas coming up from below.

The researchers also studied several deeper PLFs during the 2010 expedition. They dropped core tubes into the tops of these mounds. When the cores were lifted back onto the ship, the sediments inside fizzed and bubbled for up to an hour. The sediment was chock full of methane hydrates. Paull said, "We knew that there was a lot of gas venting going on down there, and now we have good reasons to believe that methane hydrates are present within the surface sediments. But our ROV couldn't dive deep enough, so we weren't able to go down and see what these areas actually looked like." That's one reason the team is heading back to the Arctic in 2012.

MBARI researchers tested this new mini-ROV
in the institute's test tank before sending it out
to face the challenges of the Arctic Ocean.
Image: Todd Walsh © 2012 MBARI

Heading back for more

For the 2012 expedition, the team will continue its strategy of following the topography to study areas of gas venting in the Beaufort Sea. They plan to focus on three circular, flat-topped mounds on the continental slope. The researchers believe that these pingo-like features form at the tops of "chimneys" or conduits where methane is seeping up from sediments hundreds of meters below the seafloor.

During his previous cruises, Paull used a small ROV that could dive only about 120 meters below the surface. However, the mounds on the continental slope are in about 300 to 800 meters of water. So MBARI engineers Dale Graves and Alana Sherman designed and built an entirely new ROV just for this expedition. The new ROV is small, portable, agile, relatively inexpensive, and can dive to 1,000 meters. It can also be launched and operated by just two people (for the 2012 expedition, those two people will be Graves and Sherman).

Amazingly, the new mini-ROV went from initial design to final field tests in only 15 months. But the vehicle's simple yet elegant design reflects Graves' decades of experience designing ROVs and underwater control systems. "It was a fun project for me," Graves said. "A dream come true. We designed it from scratch with a budget of just $75,000, not including labor. We mostly reused parts from MBARI's older ROVs, and built the rest in house. MBARI's electrical and mechanical technicians and machinists worked on it in between their other projects."

In addition to a state-of-the-art high-definition video camera, the ROV carries a special system for collecting methane gas bubbles. This is not as easy as it sounds, because the methane gas has a tendency to turn back into solid methane hydrate, which blocks the flow of any additional methane gas into the system. The new ROV's gas collection system includes a built-in heater to melt the hydrates and keep the gas flowing.

In addition to collecting samples of gas, the ROV will be used to look for communities of tubeworms or clams that typically grow around seafloor methane seeps. Paull said, "Nobody has ever found a living chemosynthetic biological community in the Arctic proper. But I think we have a good chance of finding them at the tops of these structures."

Dale Graves tests the control system for MBARI's new
mini-ROV in the lab before the Arctic expedition.
The entire system fits in just three small shipping cartons.
Image: Todd Walsh © 2012 MBARI

Addressing the big questions

Although the researchers have begun to understand where the gas in the Beaufort Sea is coming from, many other questions remain. One of the big questions the researchers are trying to answer is whether the three gas chimney structures on the continental slope are related to the gas venting systems in shallower water, on the continental shelf. As Paull put it, "Are they independent gas-venting structures that just happen to be together, or are they all part of the same system?"

Another important question is how all this methane gas affects the stability of the seafloor. When methane hydrates warm up and release methane gas, the gas takes up much more space than the solid hydrate, putting pressure on the surrounding sediments. Similarly, the decomposition of either methane hydrate or permafrost can reduce the mechanical strength of the surrounding sediment. Either process could make the seafloor more susceptible to submarine landslides.

Undersea landslides are common along the continental slope of the Beaufort Sea, but researchers do not yet know when or how they form. However, decomposing methane hydrates are believed to have triggered major landslides in other deep-sea areas. Such landslides could potentially destabilize oil platforms, pipelines, or other equipment on the seafloor, and have the potential to generate tsunamis.

If there is time during the 2012 cruise, the researchers hope to perform ROV dives on one or more underwater-landslides. In Fall 2013, when the team returns to the Beaufort Sea for a fourth time, these features will become the primary focus. During that expedition, the team also hopes to use one of MBARI's autonomous underwater vehicles (AUVs) to make very detailed maps of the shelf edge, the underwater landslides, and areas where methane is bubbling out of the seafloor.

Oil and gas companies have known for decades that deep oil and natural gas deposits exist in the sediments below the continental slope of the Beaufort Sea. With the warming of the Arctic and the retreat of sea ice, these hydrocarbons have become more accessible. However, it remains to be seen whether they can be extracted safely, economically, and without excessive environmental damage. Thus, the team's research will not only provide new insights into previously unknown geological processes, but will also provide important information for decision-makers involved in oil and gas permitting.

---

For more information on this article, please contact MBARI.

Related links:

• Charlie Paull's web site describing first-hand observations of methane bubbling out of seafloor during the Arctic 2010 expedition (includes video clips).
• Article describing the origin of seafloor mounds in the Beaufort Sea.
• Article on Paull's initial research regarding pingos and pingo-like-features on the seafloor.
• Charlie Paull's web site
• Web site of the Geological Survey of Canada

Source: Monterey Bay Aquarium Research Institute news release

Supplementary evidence by Prof. Peter Wadhams

Supplementary written evidence 
submitted by Professor Peter Wadhams 
to the Environmental Audit Committee (EAC)

http://www.publications.parliament.uk/pa/cm201012/cmselect/cmenvaud/writev/1739/arc26.htm

I am writing in response to information provided recently by Professor Julia Slingo OBE, Chief Scientist, Meteorological Office, firstly in the report 'Possibility and Impact of Rapid Climate Change in the Arctic' to the Environmental Audit Committee and subsequently in answering questions from the Committee on Wednesday 14 March 2012. In the responses, the Meteorological Office refers to an earlier presentation to the Committee by myself, made on 21 February 2012.

The following comments are based on the uncorrected transcript of Professor Slingo’s presentation to the EAC, 14 March 2012 session, as at: 
http://www.publications.parliament.uk/pa/cm201012/cmselect/cmenvaud/uc1739-iv/uc173901.htm

1. Speed of ice loss

In response to questions from the Chair, Prof. Slingo ruled out an ice-free summer by as early as 2015. Furthermore, Prof. Slingo rejected data which shows a decline in Arctic sea ice volume of 75% and also rejected the possibility that further decreases may cause an immediate collapse of ice cover.

The data that Prof. Slingo rejected are part of PIOMAS, which is held in high regard, not only by me, but also by many experts in the field. From my position of somebody who has studied the Arctic for many years and has been actively participating in submarine measurements of the Arctic ice thickness since 1976, it seems extraordinary to me that for Prof. Slingo can effectively rule out these PIOMAS data in her consideration of the evidence for decreasing ice volume, when one considers the vast effort and diligence that has been invested over such an extended period in collecting data under the ice by both British and US scientists. Prof. Slingo offers no reason whatsoever for dismissing this extremely pertinent set of measurements and their associated interpretation, arguing that "the observational estimates are still very uncertain". This is not the case. I expand on this in an Appendix to my letter.

It has to be said that it is very poor scientific practice to reject in such a cavalier fashion any source of data that has been gathered according to accepted high scientific standards and published in numerous papers in high-profile journals such as Nature and Journal of Geophysical Research, the more so when the sole reason for this rejection appears to be perceived uncertainty. If other data are in conflict with one’s own data, then caution should be given to the validity of one’s own data, while this should immediately set in train further research and measurement in efforts to resolve possible conflicts. In this case, however, the crucial point is that there is currently no rival set of data to compare with the scale and comprehensiveness of the PIOMAS data; Prof. Slingo sets against the clear observational database only the Met. Office’s models. These models (and in fact all the models used by IPCC) have already shown themselves to be inadequate in that they failed to predict the rapid decline in sea ice area which has occurred in recent years. It is absurd in such a case to prefer the predictions of failed models to an obvious near-term extrapolation based on observed and measured trends.

Regarding the possibility of an imminent collapse of sea ice, Prof. Slingo ignores a point raised earlier by herself, i.e. that, apart from melting, strong winds can also influence sea ice extent, as happened in 2007 when much ice was driven across the Arctic Ocean by southerly winds (not northerly, as she stated). The fact that this occurred can only lead us to conclude that this could happen again. Natural variability offers no reason to rule out such a collapse, since natural variability works both ways, it could bring about such a collapse either earlier or later than models indicate.

In fact, the thinner the sea ice gets, the more likely an early collapse is to occur. It is accepted science that global warming will increase the intensity of extreme weather events, so more heavy winds and more intense storms can be expected to increasingly break up the remaining ice, both mechanically and by enhancing ocean heat transfer to the under-ice surface.

The concluding observation I have to make on this first point is that Prof. Slingo has not provided any justification for ignoring the measurements that we have of ice volume changes and the clear trend towards imminent ice-free summers that they indicate.

2. Methane – potential emissions and escalation

My second point of contention is Prof. Slingo’s position on the possibility of imminent large releases of methane in the Arctic, which is consistent with her sanguine attitude to the rate of loss of ice cover. She states "Our estimates of those (large releases of methane) are that we are not looking at catastrophic releases of methane." Prof Slingo suggests that there was "a lack of clarity in thinking about how that heating at the upper level of the ocean can get down, and how rapidly it can get down into the deeper layers of the ocean". This appears to show a lack of understanding of the well-known process of ocean mixing. As Prof. Slingo earlier brought up herself, strong winds can cause mixing of the vertical water column, bringing heat down to the seabed, especially so in the shallow waters of the East Siberian Arctic Shelf. A recent paper shows that "data obtained in the ESAS during the drilling expedition of 2011 showed no frozen sediments at all within the 53 m long drilling core" (Dr. Natalia Shakhova et al. in: EGU General Assembly 2012;
http://meetingorganizer.copernicus.org/EGU2012/EGU2012-3877-1.pdf ).

The East Siberian Arctic Shelf (ESAS), where the intensive seabed methane emissions have been recorded, is only about 50 m deep. Throughout the world ocean, the Mixed Layer (the near-surface layer where wind-induced mixing of water occurs) is typically 100-200 m deep. It is shallower only in areas where the water is extremely calm. This used to be the case for the Arctic Ocean because of its ice cover, but it is no longer the case, because of the large-scale summer sea ice retreat which has created a wide-open Beaufort Sea where storms can create waves as high as in any other ocean, which exert their full mixing effect on the waters. It is certain that a 50 m deep open shelf sea is mixed to the bottom, so I am at a loss to understand Prof. Slingo’s remarks, unless she is thinking of the deep ocean or deeper shelves elsewhere than the East Siberian Sea.

Furthermore, Prof. Slingo states that "where there is methane coming out of the continental shelf there it is not reaching the surface either, because again the methane is oxidised during its passage through the sea water and none of those plumes made it to the surface. So there is a general consensus that only a small fraction of methane, when it is released through this gradual process of warming of the continental shelf, actually reaches the surface." This statement is also incomprehensible as far as the East Siberian Arctic Shelf is concerned. With such a shallow water depth the methane plume reaches the surface within a few seconds of release, giving little opportunity for oxidation on the way up. She may be confusing this situation with that of the much deeper waters off Svalbard where methane plumes are indeed observed to peter out before reaching the surface, due to oxidation within the water column.

To illustrate the reality of this warming of ESAS shelf water, I reproduce (fig. 1) a satellite sea surface temperature data (SST) map from September 2011, provided by Dr James Overland of Pacific Marine Environmental Laboratory (PMEL), Seattle. This shows that in summer 2011 the surface water temperature in the open part of the Beaufort and Chukchi seas reached a massive 6-7°C over most of the region and up to 9°C along the Arctic coast of Alaska. This is warmer than the temperature of the North Sea at Scarborough yesterday. This extraordinary warming is due to absorption of solar radiation by the open water. These are not the temperatures of a very thin skin as suggested by Prof. Slingo. The NOAA data apply to the uppermost 7 m of the ocean, while PMEL has backup data from Wave Gliders (automatic vehicles that run oceanographic surveys at preprogrammed depths) to show that this warming extends to at least 20 m. We can conclude from fig.1 that an extraordinary seabed warming is taking place, certainly sufficient to cause rapid melt of offshore permafrost, and this must cause serious concern with respect to the danger of a large methane outbreak.

Once the methane reaches the surface, one should note that there is very little hydroxyl in the Arctic atmosphere to break down the methane, a situation that again becomes even worse with large releases of methane.

3. The choice of pursuing geo-engineering or not.

Finally, I would like to address Prof. Slingo’s closing remarks on geo-engineering.

Both Professor Slingo and Professor Lenton repeat a point made by many critics of geo-engineering that once you start geoengineering you have to continue. On this point, I like to draw attention to evidence earlier provided to the Environmental Audit Committee by Professor Stephen Salter, as can be found at
http://www.publications.parliament.uk/pa/cm201012/cmselect/cmenvaud/writev/1739/arc22.htm

Prof. Salter responds: "I must disagree. You have to continue only until emissions have fallen sufficiently or CO2 removal methods have proved effective or there is a collective world view that abrupt global warming is a good thing after all. No action by the geo-engineering community is impeding these. Indeed everyone working in the field hopes that geoengineering will never be needed but fears that it might be needed with the greatest urgency. This is like the view of people who hope and pray that houses will not catch fire and cars will not crash but still want emergency services to be well trained and well equipped with ambulances and fires engines." Basically he is talking about the precautionary principle.

I fully agree with Prof. Salter on this point, and I also fully share with Prof. Salter the anxieties of the Arctic Methane Emergency Group. A highly proactive geo-engineering research programme aimed at mitigating global warming is more rational than expecting the worst but not taking any action to avert it.

Peter Wadhams,
Professor of Ocean Physics,
Department of Applied Mathematics and Theoretical Physics (DAMTP),
University of Cambridge
Member of Arctic Methane Emergency Group; Review Editor for Intergovernmental Panel on Climate Change 5th Assessment (chapter 1).

FIG.1. September 12-13 2011. NOAA-6 and-7 imagery of sea surface temperature in Beaufort Sea (courtesy of J. Overland). Alaska is brown land mass in bottom half. Note 6-7°C temperatures (green) in west, over East Siberian Shelf, and up to 9°C (orange) along Alaskan coast.

Appendix. The scientific database for sea ice loss.

On a previous occasion (21 February) I testified to the Committee and showed them the results of submarine measurements of ic thickness combined with satellite observations of ice retreat. When these two datasets are combined , they demonstrate beyond doubt that the volume of sea ice in the Arctic has seriously diminished over the past 40 years, by about 75% in the case of the late summer volume. If this decline is extrapolated, then without the need for models (which have demonstrably failed to predict the rapid retreat of sea ice in the last few years) it can be easily seen that the summer sea ice will disappear by about 2016 (plus or minus about 3 years). It might be useful to summarise the history of research in this subject.

In her testimony Prof Slingo placed her faith in model predictions and in future data to come from satellites on thickness (presumably Cryosat-2, which has not yet produced any usable data on ice thickness). Yet since the 1950s US and British submarines have been regularly sailing to the Arctic (I have been doing it since 1976) and accurately measuring ice thickness in transects across that ocean. Her statement that "we do not know the ice thickness in the Arctic" is false. In 1990 I published the first evidence of ice thinning in the Arctic in Nature (Wadhams, 1990). At that stage it was a 15% thinning over the Eurasian Basin. Incorporating later data my group was able to demonstrate a 43% thinning by the late 1990s (Wadhams and Davis, 2000, 2001), and this was in exact agreement with observations made by Dr Drew Rothrock of the University of Washington, who has had the main responsibility for analyzing data from US submarines (Rothrock et al., 1999, 2003; Kwok and Rothrock, 2009) and who examined all the other sectors of the Arctic Ocean. In fact in his 2003 paper Rothrock showed that in every sector of the Arctic Ocean a substantial hickness loss had occurred in the preceding 20 years. Further thinning has since been demonstrated, e.g. see my latest paper on this (Wadhams et al., 2011). Among the foremost US researchers at present active on sea ice volume decline are Dr Ron Kwok of the NASA Jet Propulsion Laboratory and Dr Axel Schweiger of University of Washington (leader of the PIOMAS project), and these have both been moved to write to Prof Slingo expressing their surprise at her remarks deriding the scientific database.

Even if we only consider a 43% loss of mean thickness (which was documented as occurring up to 1999), the accompanying loss of area (30-40%) gives a volume loss of some 75%. Summer melt measurements made in 2007 in the Beaufort Sea by Perovich et al. (2008) showed 2 m of bottom melt. If these enhanced melt rates are applied to ice which is mainly first-year and which has itself suffered thinning through global warming, then it is clear that very soon we will be facing a collapse of the ice cover through summer melt being greater than winter growth. These observations do not just come from me but also from the PIOMAS project at the University of Washington (a programme to map volume change of sea ice led by Dr Rothrock himself and Dr Schweiger), the satellite-based work of Ron Kwok, and the high-resolution modelling work of Dr Wieslaw Maslowsky at the Naval Postgraduate School, Monterey (e.g. Maslowsky et al 2011).

References

Kwok, R., and D. A. Rothrock ( 2009 ), Decline in Arctic sea ice thickness from submarine and ICESat records: 1958- 2008,Geophys. Res. Lett ., 36, L15501.

Maslowsky, W., J. Haynes, R. Osinski, W Shaw (2011). The importance of oceanic forcing on Arctic sea ice melting. European Geophysical Union congress paper XY556. See also Proceedings, State of the Arctic 2010, NSIDC.

Perovich, D.K., J.A. Richter-Menge, K.F. Jones, and B. Light (2008). Sunlight, water, ice: Extreme Arctic sea ice melt during the summer of 2007. Geophysical Research Letters 35: L11501. doi: 10.1029/2008GL034007 .

Rothrock, D.A., Y. Yu, and G.A. Maykut. (1999). Thinning of the Arctic sea-ice cover . Geophysical Research Letters 26: 3469–3472.

Rothrock, D.A., J. Zhang, and Y. Yu. (2003). The arctic ice thickness anomaly of the 1990s: A consistent view from observations and models. Journal of Geophysical Research 108: 3083. doi: 10.1029/2001JC001208 .

Shakhova, N. and I. Semiletov (2012). Methane release from the East-Siberian Arctic Shelf and its connection with permafrost and hydrate destabilization: First results and potential future development. Geophys. Res., Vol. 14, EGU2012-3877-1.

Wadhams, P. (1990). Evidence for thinning of the Arctic ice cover north of Greenland. Nature 345: 795–797.

Wadhams, P., and N.R. Davis. (2000). Further evidence of ice thinning in the Arctic Ocean. Geophysical Research Letters 27: 3973–3975.

Wadhams, P., and N.R. Davis (2001). Arctic sea-ice morphological characteristics in summer 1996. Annals of Glaciology 33: 165–170.

Wadhams, P., N Hughes and J Rodrigues (2011). Arctic sea ice thickness characteristics in winter 2004 and 2007 from submarine sonar transects. J. Geophys. Res., 116, C00E02.

Rebuttal: David Archer wrong to dismiss concern about potential methane runaway in Arctic

               REBUTTAL:

               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  

  

                                    by Gary Houser

         "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 Jan. 4 entry on the "Real Climate" blog (2) , David Archer links to a rebuttal I wrote to oppose Andrew Revkin's "Dot Earth" dismissal of an article in the UKIndependent 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 which 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 - such as 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 "Real Climate" and even more recently to Joe Romm's "Climate Progress". On Jan.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 "nightmare" 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 Univ. of Calif - 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 (Paleocene-Eocene Thermal Maximum - 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 underlines 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:

A) The incredible warming power of methane as a greenhouse gas (already quantified);  B) The phenomenally huge volume of methane present in the continental shelf areas of the Arctic;  C) The quite shallow depth of these seabeds, which allows direct venting to the surface and atmosphere (methane otherwise safely oxidizes in deep water);  D) 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;  E) Direct observations confirming that large scale methane plumes are venting to the surface and into the atmosphere;  and F) 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 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.

  

THE CASE FOR URGENCY REGARDING THE METHANE THREAT:    

 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 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. Carana explores the connection between ice loss, warming temperatures in the Arctic, and the release of methane. (20) and (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 occuring are being caused by human-made warming, it seems he is having difficulty - as many of us are, including myself -  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 course. With all respect, I must ask  why make a gamble that could lead to 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 Real Climate 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 (such as 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.   

  

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 Real Climate 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 Real Climate 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 Real Climate - as well as the larger community of climate scientists - will rise to the occasion and show the way.                            Gary Houser          Co-producer and writer                                 "Sleeping Giant of the Arctic:               Could Thawing Methane Trigger Runaway Global Warming?"                                  www.590films.org/methane.html      ----------------------------------------------------------------------------------------------- IMAGES: Methane bubbles from: Sauter et al. dx.doi.org/10.1016/j.epsl.2006.01.041 East Siberian Arctic Shelf map from: Sodahead Arctic sea ice volume decline graph by Wipneus based on PIOMAS data. LINKS and NOTES:   (1)  UK Independent, Dec.13, 2011 Vast methane 'plumes' seen in Arctic ocean as sea ice retreats ...  (2)  RealClimate: Much ado about methane (3)  Vast methane 'plumes' seen in Arctic ocean as sea ice retreats ...  (4)   Arctic sea ice 'to melt by 2015' - Telegraph  (5)  RealClimate Is Alarmed by Arctic Methane, Should You Be ... (6)  Global-warming potential - Wikipedia, the free encyclopedia (7)  Documentary interview with Leifer  www.590films.org/methane.html  , (in progress);  the crew has interviewed climate scientists Igor Semiletov and Natalia Shakhova (Internat'l Arctic Research Center / IARC at the Univ. of Alaska - Fairbanks), Ira Leifer (Marine Science Institute at Univ. of Calif.-Santa Barbara), Vladimir Romanovsky (IARC), and Katey Walter (Univ. of Alaska - Fairbanks). On geological history and extinction events, paleo-climatologists Michael Benton (Univ. of Bristol in UK, author of book When Life Nearly Died) and Andrew Glikson (Australian National Univ. in Canberra). Also in consultation with Peter Wadhams of the Univ. of Cambridge - one of the top Arctic ice experts in the UK.  (8)  Wipeout: the end-Permian mass extinction  (9)  Nine minute segment from "Miracle Planet" :  http://www.youtube.com/watch?v=exfNNDExxIc&list=PL0200B1524E220C5A&feature=player_embedded  (10)  Interview segment with James Hansen:  http://youtu.be/ACHLayfA6_4    (11)  from Hansen's book Storms of My Grandchildren (12)  Documentary interview with Semiletov   www.590films.org/methane.html  (13)  M.I.T. Study,  M.I.T. doubles its 2095 warming projection to 10°F — with 866 ppm and Arctic warming of 20°F (14)  M.I.T. Study,  M.I.T. doubles its 2095 warming projection to 10°F — with 866 ppm and Arctic warming of 20°F (15)  Arctic sea ice 'to melt by 2015' - Telegraph  (16)  PIOMAS graph link: http://neven1.typepad.com/.a/6a0133f03a1e37970b0153920ddd12970b-pi (17)  Arctic sea ice 'to melt by 2015' - Telegraph  (18)   Archer, co-author  Gas hydrates: entrance to a methane age or climate ... - IOPscience  (19)  Documentary interview with Semiletov   www.590films.org/methane.html  (20)  http://arctic-news.blogspot.com/p/warming-in-arctic.html (21)  http://arctic-news.blogspot.com/p/potential-for-methane-release.html  (22)  http://arctic-news.blogspot.com/p/warming-in-arctic.html (23)  RealClimate Is Alarmed by Arctic Methane, Should You Be ... (24)  Arctic Methane Emergency Group (AMEG) website:   www.arctic-methane-emergency-group.org