Proposal to extract, store and sell Arctic methane

A Proposal for the Prevention of

Arctic Methane Induced Catastrophic

Global Climate Change by Extraction

of Methane from beneath the Permafrost/

Arctic Methane Hydrates and its Storage and

Sale as a Subsidized "Green Gas"

Energy Source

By Malcolm P.R. Light

PhD. UCL
May 27th, 2012

DEDICATION

This proposal is dedicated to my Father and Mother, Ivan and Avril Light,

both meteorologists and farmers who knew about the vagaries of the weather;

and to all our grandchildren whose entire future depends on its successful outcome.

EXECUTIVE SUMMARY

Methane hydrates (clathrates) exist on the Arctic submarine shelf and slope where they are stabilized by the low temperatures and they have a continuous cap of frozen permafrost which normally prevents methane escape (Figure 1 below).

However, recent research has shown that millions of tons of methane are already being released in the Siberian Arctic through perforated zones in the subsea permafrost cap with the concentrations reaching up to 100 times the normal, such as in the discharge region of the Lena River and the junction of the Laptev and East Siberian Seas (Shakova et al. 2010).

Mean methane concentrations in the Arctic atmosphere showed a striking anomalous buildup between November 1-10, 2008 and November 1-10, 2011 (Figure 2 above)(Yurganov 2012 in Carana, 2012a).

The surface temperature hotspots in the Arctic caused by global warming correlate well with the anomalous buildups of atmospheric methane in the Arctic (Figure 3 right, in Arctic feedbacks in Carana, 2012a).

This indicates that there is a strong correlation between the dissociation of Arctic subsea methane hydrates from the effects of globally warmed seawater and the increasing size and rate of eruptions of methane into the Arctic atmosphere.

• Methane eruption zones (torches) occur widely in the East Siberian Arctic Shelf (ESAS) (Shakova et al., 2008; 2010), but the largest and most extreme are confined to the region outside the ESAS where the Gakkel "mid ocean" ridge system intersects at right angles the methane hydrate rich shelf slope region (Figure 9 above and Figure 17 right). 
  
  The wedge-like opening and spreading of the Gakkel Ridge is putting the formations and overlying methane hydrate sediments under torsional stress and in the process activating the major strike slip faults that fan away and thrust faults that radiate from this region (Figure 16 below). 
  
  Light and Solana (2002) predicted that the north slope of the Barents - Laptev - East Siberian seas at the intersection of the slowly opening Gakkel Ridge. This region would be especially vulnerable to slope failures where unstable methane hydrate would be affected by seismicity from earthquakes with magnitudes greater then 3.5 Richter and at depths of less than 30 km. Many earthquakes occur along the Gakkel Ridge often with magnitudes greater than 4 to 6 and at depths shallower than 10 km (Avetisov, 2008) continuously destabilizing the already unstable methane hydrates there (Figure 16 below). 

• Major and minor strike slip and normal faults form a continuous subterranean network around the Gakkel Ridge and are clearly charged with overpressured methane because methane gas is escaping from these fault lines many hundreds of km up dip and away from the subsea methane hydrate zones through which these fault zones pass (Figures 9 above and Figure 18 right).
   
• One small methane eruption zone occurs directly over the centre of the Gakkel Ridge and probably represents thermogenic deep seated methane being released by the magmatic heating of adjacent oil/gas fields by rising (pyroclastic) magma (Figure 9 above)(Edwards et al. 2001). This surface gas eruption appears to only represent a tiny percentage of the total gas released from other sources such as methane hydrates, as do methane eruptions around Cenozoic volcanics offshore Tiksi on the East Siberian shelf (Figure 11 right and Figure 16 above).
  
  
• An elongated set of methane eruption zones occur on the submarine slope north of Svalbard flanking the Gakkel Ridge and result from methane hydrate decomposition caused by sudden changes in pressure and temperature conditions due to submarine slides/slumps (Figure 9 above). These submarine slides/slumps were evidently set off by seismic activity along the Gakkel Ridge which lies a short distance to the north in an area where the ridge opening is the widest (Figure 16 above). This may be similar to the Storegga slide (Light and Solana, 2002; NGI, 2012). Light and Solana (2002) predicted that the western slopes of Norway and along the Barents Sea to Svalbard, would be especially vulnerable to slope failures in regions of unstable methane hydrate. Here the slowly spreading Gakkel Ridge runs as close as 30 km to the slope. Earthquake activity along the Gakkel Ridge often has magnitudes greater than 4 to 6 at depths shallower than 10 km (Avetisov, 2008) and will also be destabilizing the already unstable methane hydrates here leading to eruptions of methane into the atmosphere (Figure 9 above and Figure 16 above).

There are some 1000 Gt to 1400 Gt (10^9 tonnes) of carbon contained in the methane hydrates on the East Siberian Arctic Shelf and 700 Gt of free methane is trapped under the Arctic submarine permafrost (Shakova et al. 2008, 2010). Shakova et al. estimate that between 5% to 10% of the subsea permafrost (methane hydrates) in that region is now punctured allowing methane to escape at a rate of about 0.5 Mt (500,000 tonnes) a year and that up to 50 Gt (10^9 tonnes) could be released abruptly at any time soon. Release of this subsea Arctic methane would increase the worldwide atmospheric methane content about 12 times equivalent to doubling the carbon dioxide content of the atmosphere. This "methane hydrate gun", which is cocked and ready to fire at any moment, is an extremely serious scenario that will cause abrupt climate change (CCSP, 2008; IMPACTS 2008). Even if this subsea volume of Arctic methane is released over a longer interval of some ten to twenty years it will still result in a massive feedback on global warming and drive the Earth on an irretrievable plunge into total extinction.

Figure 5. From: Carana 2012b, originally from: arctische pinguin - click to enlarge

After 2015, when the Arctic Ocean becomes navigable (Figure 5 above, Carana 2012b) it will be possible to set up a whole series of drilling platforms adjacent to, but at least 1 km away from the high volume methane eruption zones and to directionally drill inclined wells down to intersect the free methane below the sealing methane hydrate permafrost cap within the underlying fault network (Figure 18 above).

High volume methane extraction from below the subsea methane hydrates using directional drilling from platforms situated in the stable areas between the talik/fault zones will reverse the methane and seawater flow in the taliks and shut down the uncontrolled methane sea water eruptions (Figure18 above). The controlled access of globally warmed sea water drawn down through the taliks to the base of the methane hydrate - permafrost cap will gradually destabilize the underlying methane hydrate and allows complete extraction of all the gas from the methane hydrate reserve (Figure18 above). The methane extraction boreholes can be progressively opened at shallower and shallower levels as the subterranean methane hydrate decomposes allowing the complete extraction of the sub permafrost reserve (Figure18 above).

The methane and seawater will be produced to the surface where the separated methane will be processed in Floating Liquefied Natural Gas (FLNG) facilities and stored in LNG tankers for sale to customers as a subsidised green alternative to coal and oil for power generation, air and ground transport, for home heating and cooking and the manufacture of hydrogen, fertilizers, fabrics, glass, steel, plastics, paint and other products.

Where the trapped methane is sufficiently geopressured within the fault system network underlying the Arctic subsea permafrost and is partially dissolved in the water (Light, 1985; Tyler, Light and Ewing, 1984; Ewing, Light and Tyler, 1984) it may be possible to coproduce it with the seawater which would then be disposed of after the methane had be separated from it for storage (Jackson, Light and Ayers, 1987; Anderson et al., 1984; Randolph and Rogers, 1984; Chesney et al., 1982).

Many methane eruption zones occur along the narrow fault bound channels separating the complex island archipelago of Arctic Canada (Figure 6 and 9). In these regions drilling rigs could be located on shore or offshore and drill inclined wells to intersect the free methane zones at depth beneath the methane hydrates, while the atmospheric methane clouds could be partly eliminated by using a beamed interfering radio transmission system (Lucy Project) (Light 2011a). A similar set of onshore drilling rigs could tap subpermafrost methane along the east coast of Novaya Zemlya (Figure 6 below and 9 above).

Methane is a high energy fuel, with more energy than other comparable fossil fuels (Wales 2012). As a liquid natural gas it can be used for aircraft and road transport and rocket fuel and produces little pollution compared to coal, gasoline and other hydrocarbon fuels.

Support should be sought from the United nations, World Bank, national governments and other interested parties for a subsidy (such as a tax rebate) of some 5% to 15% of the market price on Arctic permafrost methane and its derivatives to make it the most attractive LNG for sale compared to LNG from other sources. This will guarantee that all the Arctic gas recovered from the Arctic methane hydrate reservoirs and stockpiled, will immediately be sold to consumers and converted into safer byproducts. This will also act as an incentive to oil companies to produce methane in large quantities from the Arctic methane hydrate reserves. In this way the Arctic methane hydrate reservoirs will be continuously reduced in a safe controlled way over the next 200 to 300 years supplying an abundant "Green LNG" energy source to humanity.

Video and poster - methane in the Arctic

Methane in the Arctic threatens to escalate into runaway global warming.

The poster shown in the video is added below. 

Click on the poster to view a higher-resolution version, for printing out and hanging it on the wall.

Methane in the Arctic

Methane is often said to have a Global Warming Potential (GWP) of 21 times as strong as carbon dioxide, a figure based on IPCC assessment reports that date back to the 1990s. However, the IPCC has updated methane's GWP several times since, as illustrated in Table 1. below.

In its Fourth Assessment Report (AR4, 2007), the IPCC gives methane a GWP of 25 as much as carbon dioxide over 100 years and 72 as much as carbon dioxide over 20 years.

Furthermore, a 2009 study, by Drew Shindell et al., points out that the IPCC figures do not include direct+indirect radiative effects of aerosol responses to methane releases that increase methane's GWP to 105 over 20 years when included

Moreover, in the context of tipping points, which seems appropriate regarding methane releases in the Arctic, it makes sense to focus on a short time horizon, possibly as short as a few years.

Accordingly, methane's GWP can best be visualized as in the image below, which is also displayed mid-right on the poster above.

The image on the left shows methane's global warming potential (GWP) for different time horizons, pointing out that methane's GWP is more than 130 times that of carbon dioxide over a period of ten years.

IPCC¹ figures were used to create the blue line. The red line is based on figures in a study by Shindell et al.², which are higher as they include more effects. This study concludes that methane's GWP would likely be further increased by including ecosystem responses.

The ecosystem response can be particularly strong in the Arctic, where the seabed contains huge amounts of methane. Continued warming in the Arctic can cause large abrupt methane releases which in turn can trigger further methane releases from sediments under the sea.

This is particularly worrying, not only because of the presence of huge amounts of methane, but also because the sea is quite shallow in areas such as the East Siberian Arctic Shelf (ESAS), which in the case of large abrupt releases can soon lead to oxygen depletion in the water and make that much of the methane will enter the atmosphere without being oxidized in the water.

Additionally, low water temperatures and long sea currents in the Arctic Ocean are not very friendly toward bacteria that might otherwise break down methane in the water.

For further background, also see the post The potential impact of large abrupt release of methane in the Arctic at the Arctic Methane blog³, and the FAQ page at that blog.

References:

1. IPCC, Climate Change 2007: Working Group I: The Physical Science Basis, Table 2.14 (2007)
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch2s2-10-2.html

2. D.T. Shindell et al., "Improved Attribution of Climate Forcing to Emissions". Science vol 326: pp. 716-718 (2009)
http://www.sciencemag.org/content/326/5953/716.abstract

3. Sam Carana, The potential impact of large abrupt release of methane in the Arctic (2012)
http://arcticmethane.blogspot.com/2012/05/potential-impact-of-large-abrupt.html

Methane levels high above ESAS, March-April 2012

Methane levels have been high above the East Siberian Arctic Shelf for both the months March and April 2012, as illustrated by the image below.

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: 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

---

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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