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Senin, 07 April 2014

Permafrost thawing could accelerate global warming

"If the permafrost melts entirely, there would be 5x the amount of carbon in the atmosphere than there is now" - Jeff Chanton

Jeff Chanton, the John Widmer
Winchester Professor of
Oceanography at Florida State.

A team of researchers lead by Florida State University have found new evidence that permafrost thawing is releasing large quantities of greenhouse gases into the atmosphere via plants, which could accelerate warming trends.

The research is featured in the newest edition of the Proceedings of the National Academy of Sciences.

“We’ve known for a while now that permafrost is thawing,” said Suzanne Hodgkins, the lead author on the paper and a doctoral student in chemical oceanography at Florida State. “But what we’ve found is that the associated changes in plant community composition in the polar regions could lead to way more carbon being released into the atmosphere as methane.”

Permafrost is soil that is frozen year round and is typically located in polar regions. As the world has gotten slightly warmer, that permafrost is thawing and decomposing, which is producing increased amounts of methane.

Relative to carbon dioxide, methane has a disproportionately large global warming potential. Methane is 33 times more effective at warming the Earth on a mass basis and a century time scale relative to carbon dioxide.

Changes in plant community composition in the polar regions could lead to way more carbon being released into the atmosphere as methane

As the plants break down, they are releasing carbon into the atmosphere. And if the permafrost melts entirely, there would be five times the amount of carbon in the atmosphere than there is now, said Jeff Chanton, the John Widmer Winchester Professor of Oceanography at Florida State.

“The world is getting warmer, and the additional release of gas would only add to our problems,” he said.

Chanton and Hodgkins’ work, “Changes in peat chemistry associated with permafrost thaw increase greenhouse gas production,” was funded by a three-year, $400,000 Department of Energy grant. They traveled to Sweden multiple times to collect soil samples for the study.

The research is a multicontinent effort with researchers from North America, Europe and Australia all contributing to the work.

References

- Permafrost thawing could accelerate global warming - Florida State University news release
http://news.fsu.edu/More-FSU-News/Permafrost-thawing-could-accelerate-global-warming

- Changes in peat chemistry associated with permafrost thaw increase greenhouse gas production

http://www.pnas.org/content/early/2014/04/02/1314641111

Minggu, 15 Desember 2013

Methane emerges from warmer areas

As the year draws to a close, it's time to review where warming has occured most strongly in 2013. Surface temperature anomalies in November 2013 were 0.77°C, the highest global November anomalies on record. In November 2013, high temperature anomalies occurred in the Arctic, well over 9°C north and south of Novaya Zemlya.

Indeed, global warming is hitting the Arctic particularly hard, and some models have underestimated the pace at which this is occuring. Most heat goes into the oceans, which - due to the Gulf Stream - contributes to accelerated warming in the Arctic, where also less monitoring takes place than over land. Stefan Rahmstorf, Co-Chair of Earth System Analysis at the Potsdam Institute for Climate Impact Research, says at RealClimate:

A new study by British and Canadian researchers shows that the global temperature rise of the past 15 years has been greatly underestimated. The reason is the data gaps in the weather station network, especially in the Arctic. If you fill these data gaps using satellite measurements, the warming trend is more than doubled in the widely used HadCRUT4 data.

Where did warming occur most strongly in 2013? The red/orange areas on the image below shows surface temperature anomalies of more than 2°C for the year from December 13, 2012, to December 12, 2012.

As the image shows, temperature anomalies have hit Earth most strongly in the cryosphere, i.e.
- in Antarctica, as discussed at this post;
- on the Qinghai-Tibetan Plateau, as earlier discussed at this post;
- in the Arctic, as discussed below.

Over the past 90 days, the Arctic Ocean has shown surface temperature anomalies of over 5°C and in some spots over 8°C.

Looking at anomalies over longer periods can mask the occurrence of much higher anomalies on individual days. As an example, temperature anomalies of over 20°C were recorded over a large part of the Arctic Ocean on November 17, 2013.

Baffin Bay, west of Greenland, has until now received little attention. High temperature anomalies over the past year show up on the top image. These high temperatures are the more striking given that a cold sea current runs through Baffin Bay, as shown on the image below.

Methane has emerged strongly from areas that have warmed most in 2013. In August 2013, high concentrations of methane showed up over Siberia. High methane releases have further occurred in all three parts of the cryosphere mentioned above, i.e. from the heights of Antarctica, as discussed at this post, on the Qinghai-Tibetan Plateau, as earlier discussed at this post, and in the Arctic, as discussed in many posts at the Arctic-news blog.

Huge methane concentrations have featured over Baffin Bay recently. The animation below shows huge methane emissions emerging from Baffin Bay on December 2nd, 2013. The power behind these methane releases is strong enough to make it difficult for thicker ice to form in Baffin Bay. The animation below shows an area marked by a red rectangle where it looks like the water would have been covered with thicker ice, had there not been so much methane bubbling up in the area.

This area with very thin ice in Baffin Bay is further illustrated in the Naval Research Laboratory 30-day Arctic sea ice thickness animation below.

This constitues yet another feedback, i.e. methane bubbling up from the seafloor of the Arctic Ocean with a force strong enough to prevent sea ice from forming in the area.

Post by Sam Carana.

Minggu, 08 Desember 2013

CLIMATE REPORT'S HUGE OMISSION OBSCURES FULL DANGER

by Gary Houser

CLIMATE REPORT'S HUGE OMISSION OBSCURES FULL DANGER:

Grassroots Must Insist IPCC Include Massive Permafrost Carbon

"Across two decades and thousands of pages of reports, the world's most authoritative voice on climate science has consistently understated the rate and intensity of climate change and the danger those impacts represent, say a growing number of studies ....... The speed and ferocity of climate change are outpacing IPCC projections on many fronts, including CO2 emissions, temperature rise, continental ice-sheet melt, Arctic sea ice decline, and sea level rise.

The IPCC’s overly conservative reading of the science ..... means governments and the public could be blindsided by the rapid onset of the flooding, extreme storms, drought, and other impacts associated with catastrophic global warming."

— Scientific American, "Climate Science Predictions Prove Too Conservative", Dec.6, 2012 [1]

The primary scientific report used by governments of the world to guide their policies on climate has failed to convey the full danger being created by release of greenhouse gases into the atmosphere. By focusing on human-generated carbon, the Intergovernmental Panel on Climate Change (IPCC) has ignored an even more threatening process now being triggered by those emissions. Rapid warming in the Arctic - where temperatures are rising twice as fast as the global rate - is thawing an incomprehensibly vast stockpile of nature's own carbon which has been trapped in ice for millenia. This threat is described in a new mini-documentary (entitled "Last Hours" [2] ), the importance of which has been highlighted by leaders on the climate issue such as Al Gore. [3]

The scale of this threat is mind-boggling. There is over three times more heating power stored in this "permafrost" than that which has been caused by human greenhouse gas emissions since the beginning of the industrial age - and this refers only to that located on land (as opposed to the coastal seabeds). [4] This stockpile includes super greenhouse gas methane, acknowledged even by the IPCC itself to be a stunning 86 times more potent than carbon dioxide as a warming agent over 20 years (with climate-carbon feedbacks). [5]

Despite a formal appeal by scientists specializing in permafrost study that IPCC issue a special assessment drawing attention to this tremendous danger [6], the recently released report neglected to do so. The French news agency Agence France-Presse reported that due to bureaucratic delays and a log-jam in the processing of cutting edge data,

"the cut-off date meant the authors were unable to evaluate recent, but very worrying, studies that say methane trapped in ice-bound coasts in northeast Siberia is being released as seas warm, thus putting the greenhouse effect into higher gear." [7]

This massive failure by IPCC means that governments world-wide have not been given adequate warning about how preciously little time may be left to prevent the crossing of a tipping point leading to unstoppable global catastrophe. By not addressing the unique consequences brought on by accelerated Arctic warming, the IPCC is in fact skewing the picture that needs to be presented.

"Arctic and alpine air temperatures are expected to increase at roughly twice the global rate .... A global temperature increase of 3 degrees Celsius means a 6 degrees Celsius increase in the Arctic, resulting in an irreversible loss of anywhere between 30 to 85 percent of near-surface permafrost." [8]

Even worse, more cutting edge science (also not included in the IPCC report) reveals additional unsettling developments. Exposure to sunlight appears to speed up the rate of permafrost thaw: "...sunlight increases bacterial conversion of exposed soil carbon into carbon dioxide gas by at least 40 percent compared to carbon that remains in the dark." [9] This thaw on land is being matched in the shallow coastal seabeds. Natalia Shakhova - who has helped lead numerous fact-finding missions along the coast of Siberia - reports that releases there are "now on par with the methane being released from the arctic tundra." [10] She also warns that these releases can be larger and more abrupt than those resulting from decomposition on land.

As previously frozen methane vents to the atmosphere, the warming it causes can thaw and release even more. This "feedback" is capable of escalating into a "runaway" chain reaction that humanity would be helpless to stop. This is the same methane that some scientists point to as a major factor in the most sweeping mass extinctions in earth's history - the PETM and the end-Permian, the latter of which decimated 90 percent of all life forms. Whether this association can be absolutely proven or not (the scientific basis for its connection to the Permian is explored in the BBC documentary "The Day Earth Nearly Died" [11] ), no one can credibly deny the immense power of this greenhouse gas.

By omitting this crucial information, policymakers are being dangerously lulled into believing there is more time to act - and less urgency - than what is in fact the case. At precisely the moment when the world needs the most unambiguous and emphatic warning from the scientific community - a moment which may not afford humanity any second chance to recover and correct course - it is nowhere to be found.

Methane plumes rising from the seafloor

Over the years, the IPCC has been wrong numerous times in its projections. According to Scientific American:

"In the 2007 report, the IPCC concluded the Arctic would not lose its summer ice before 2070 at the earliest. But the ice pack has shrunk far faster than any scenario scientists felt policymakers should consider; now researchers say the region could see ice-free summers within 20 years." [12]

As the opening quote states, this pattern has persisted regarding several aspects of the issue. Given this history, it is not surprising the current IPCC report is again "behind the times" on the very day it is published. In the short time following its release, a large number of experts on sea level rise are already saying that the IPCC projections are too cautious and conservative. [13]

Originally created with a mission to provide government bodies with un-biased scientific facts on climate disruption in order to inform the process of policymaking, the IPCC process has become seriously impaired by a combination of internal problems and outside pressure. The result has been the production of reports that not only fail to keep up with the cutting edge of the science itself but are also tainted by a bias toward overly conservative assessments.

The same key article in Scientific American describes the internal logjam:

"Such assessments typically take five to seven years to complete in a slow, bureaucratic process: ......... a summary for policymakers, condensing the science even further, is written and subjected to a painstaking, line-by-line revision by representatives from more than 100 world governments – all of whom must approve the final summary document." [14]

Materials from scientists are only accepted for consideration after they have been peer-reviewed and published in a scientific journal. This process in itself can take up to three years. Then another requirement is that such materials cannot be submitted beyond an early cut-off date. The goal of instituting an orderly process is laudable, but the severe problem is that the pace of climate disruption is most assuredly accelerating. If vital information at the cutting edge of these frightening changes cannot make it through these hurdles in time, there is a huge gap of five or six years before it can be integrated into the next report.

A key example would be the definitive paper documenting the land-based permafrost feedbacks which asks IPCC to issue a special assessment. Not only was this request ignored, but this documentation was not even considered as it was published after the cut-off date.

The current IPCC report is quite intimidating at over 2000 pages long. A solution to both problems of timeliness and excessive length is to make the IPCC process more nimble by tackling the various key components of climate disruption individually rather than combining them all into one ponderous document. An example would be a report strictly limited to Arctic issues. As the most rapidly warming region on earth - with profound impact on the global climate - it is entirely deserving of special attention.

The second major problem is that when the IPCC was first set up, a provision was inserted which provides government entities the so-called "right" to review and approve the official Summary for Policymakers - the most important section. As the incredibly wealthy fossil fuel lobby holds great power over many governments, this provision provides an opening to pressure those governments into weakening the language. As such power was actively used to weaken segments of the last Summary in 2007, [15] it cannot be ruled out that such was used again. Scientific research should not be censored by political entities, a point made eloquently by British expert on feedback dynamics David Wasdell:

"What comes out is that which is 'acceptable' ...... from science that is about six years out of date, and that becomes the basis for negotiation and decision-making. It is grossly inappropriate....... There are many pressures ..... not least the enormous profits that continue to be made from fossil fuels." [16]

This provision should be put up for debate and stricken.

fish skeleton on parched soil, credit: Will Sherman

There is a corrective action which can be taken. Precedent already exists for the IPCC issuing a "Special Report" on aspects of the issue it considers worthy of special attention. A recent example is one on the increasing frequency of extreme weather events. There is a powerful case behind the need to release a Special Report on the threat from permafrost thaw in the Arctic. But an institution this size does not move unless there is a strong and coordinated campaign aimed at raising the issue and applying some "push". All the grassroots environmental groups that have led the climate movement are now called to recognize the dire need to integrate this frightening issue into the framework of all thinking and strategizing. If this is not done, and governments around the world continue to ignore it, there is a high likelihood that all other climate campaigns will fail.

Keystone XL Pipeline protest - photo taken Feb 13, 2013 - from: flickr.com/photos/tarsandsaction/

The valiant effort to oppose the tar sands pipeline must be continued. But this movement must recognize that the climate threats are not presenting themselves in single file - one at a time. Several dangers are simultaneously bearing down on humanity. The laws of physics driving these threats will not pause for political stagnation. If the governments of the world fail to see the sleeping giant awakening in the Arctic and adjust their collective sense of urgency accordingly, then it appears our fate is sealed. The laws of physics will run their course. We owe it to those generations that would inherit a devastated planet to do better than that.

The prospect of humanity being blindsided by a tremendous - and perhaps even fatal - blow is unthinkable. There is no "Planet B" to turn to if the conditions necessary to support life on our present planet are wiped out. Our society places great trust in the scientific community. Faced by any threat of this magnitude, our assumption is that our scientists will fulfill their moral obligation, act on the precautionary principle, and give us ample warning. In this case, that trust is being violated. It is therefore up to concerned citizens everywhere to speak out, hold them accountable, and insist that governments receive the warning that is needed. This dangerous and potentially suicidal omission must not be allowed to stand.

Who stands up for the children? - screenshot from children against climate change protest video

"The eyes of the future are looking back at us and they are praying for us to see beyond our own time. They are kneeling with hands clasped that we might act with restraint, that we might leave room for the life that is destined to come." — Terry Tempest Williams [17]

Gary Houser is a public interest writer and documentary producer focusing on climate issues and the "sleeping giant" of Arctic methane in particular, and based in Ohio in the U.S. He is seeking to network with others with similar concerns re: permafrost thaw who work in the U.S. context. Current projects are: persuading major enviro / climate groups to integrate Arctic permafrost thaw as a high priority issue into their campaigns, a specific grassroots campaign to pressure IPCC toward a Special Report, public hearing on Arctic issues in the U.S. Senate, production and broadcast of Arctic permafrost thaw documentary on one of the national TV networks in the U.S. He can be contacted at: garyhouser4@gmail.com

SOURCE LINKS:

Post by Sam Carana.

Jumat, 26 Juli 2013

Methane and the risk of runaway global warming

By Andrew Glikson

A satellite picture reveals permafrost melting around Liverpool Bay in Canada’s northwest territories. NASA Goddard Space Flight Center

Research was published this week showing the financial cost of methane being released from Earth’s permafrosts. But the risks go beyond financial – Earth’s history shows that releasing these stores could set off a series of events with calamitous consequences.

The sediments and bottom water beneath the world’s shallow oceans and lakes contain vast amounts of greenhouse gases: methane hydrates and methane clathrates (see Figure 1). In particular methane is concentrated in Arctic permafrost where the accumulation of organic matter in frozen soils covers about 24% of northern hemisphere continents (see Figure 2a) and is estimated to contain more than 900 billion tons of carbon.

Methane, a greenhouse gas more than 30 times more potent than CO₂, is released from previously frozen soils when organic matter thaws and decomposes under anaerobic conditions (that is, without oxygen present).

Most of the current permafrost formed during or since the last ice age and can extend down to depths of more than 700 meters in parts of northern Siberia and Canada. Thawing of part of the permafrost has not yet been accounted for in climate projections.

The Siberian permafrost is in particular danger. A large region called the Yedoma could undergo runaway decomposition once it starts to melt. This is because elevated temperatures cause microbes in the soil to decompose, which causes heat, which creates a self-amplifying process.

Figure 1: Global distribution of methane hydrate deposits on the ocean floor. Naval Research Laboratory

Palaeoclimate studies of stalagmite cave deposits across Siberia indicate they grew faster during the warm periods 424,000 and 374,000 years ago, due to permafrost melt. At that time, mean global temperatures rose by approximately 1.5 degrees Celsius above pre-industrial temperatures. Thus Vaks et al state: “Growth at that time indicates that global climates only slightly warmer than today are sufficient to thaw extensive regions of permafrost.”

Evidence of melting of permafrost has also been reported from the dry valleys of Antarctica, where development of thermokarst (small surface hummocks formed as ice-rich permafrost thaws) has been reported, reaching a rate about 10 times that of the last ~10,000 years.

The mean temperature of the continents has already increased by about 1.5C. With sulphur aerosols masking some of the warming, the real figure may be closer to 2C.

Figure 2a: Vulnerable carbon sinks. CSIRO Global Carbon Project

Figure 2b: Global average abundances of
carbon dioxide and methane 1978-2011

Arctic air temperatures are expected to increase at roughly twice the global rate. A global temperature increase of 3C means a 6C rise in the Arctic, resulting in an irreversible loss of anywhere between 30 to 85% of near-surface permafrost. According to the United Nations, warming permafrost could emit 43 to 135 billion ton CO₂ (GtCO₂) equivalent by 2100, and 246 to 415 GtCO₂ by 2200.
The geologically unprecedented rate of CO₂ rise (~2.75 ppm/year during June 2012-2013) may result in faster permafrost collapse.

Already measurements along the Siberian shelf uncover enhanced methane release. In 2010 a Russian marine survey conducted more than 5000 observations of dissolved methane showing that more than 80% of East Siberian shelf bottom waters and more than 50% of surface waters are supersaturated with methane. Atmospheric methane levels (during glacial periods: 300–400 parts per billion; during interglacial periods: 600–700 ppb) have recently reached 1850 ppb – the highest in 400,000 years (see Figure 2b).

Hansen et al estimate that the rise of CO₂ forcing between 1750 and 2007 has already committed the atmosphere to between +2 and +3 degrees Celsius, currently mitigated in part by sulphur aerosols.

Figure 3: Change in average annual land surface temperature since 1750. Berkeley Temperatures

Hansen refers to the “Venus Syndrome”, drawing an analogy between the enrichment of Venus’ atmosphere in CO₂ (its atmosphere is 96.5% CO₂ and its surface temperature is 462C) and potential terrestrial runaway greenhouse effects. This needs to be placed in context.

On Earth, weathering processes and oceans draw down the bulk of atmospheric CO₂ to be deposited as carbonates. It’s therefore impossible for Earth to develop Venus-like conditions. But the onset of a hyperthermal – a huge release of carbon such as happened during the Paleocene-Eocene Thermal Maximum 55 million years ago, with an attendant mass extinction of species – is possible.

Figure 4. Estimates of fossil fuel resources and equivalent atmospheric CO2 levels, including (1) emissions to date; (2) estimated reserves, and (3) recoverable resources (1 ppm CO2 ~ 2.12 GtC). Hansen, 2012, figure 1; http://www.columbia.edu/~jeh1/mailings/2012/20120127_CowardsPart1.pdf

Extraction and combustion of the current fossil fuel reserves (more than 20,000 billion tonnes of carbon – Figure 4) would inevitably lead to a hyperthermal commensurate with or exceeding the PETM. If that happens, CO₂ would rise to above 500ppm (see figure 4), temperature would rise by about 5C (figure 5) and the polar ice sheets would melt – it’s a future we could face if emissions continue to accelerate.

Figure 5: Growth in CO2 and CO2 equivalent (CO2+CH4) during the Pleistocene and the Holocene. IPCC AR4

Not that the above features too much in the Australian elections, where the reality of climate change has been replaced with pseudoscience notions, including by some who have not consulted basic climate science text books, and by hip-pocket-nerve terms such as “carbon tax”, “emission trading scheme” or “direct action”. The proposed 5% reduction in emissions relative to the year 2000 represent no more than climate window dressing.

Nor are coal exports mentioned too often, despite current exports and planned future exports, which represent carbon emissions tracking toward an order of magnitude higher than local emissions.

According to Dr Adam Lucas of the Science and Technology Studies Program at University of Wollongong, Australia (with ~0.3% of the global population) currently contributes domestic emissions of about 1.8% of global emissions. The total domestic and overseas consumption of Australian coal is responsible for more than 2% of global emissions. Plans to triple or even quadruple coal export volumes over the next 10 years would raise Australia’s total contribution to global GHG emissions to toward 9% to 11% by 2020 – an order of magnitude commensurate with that of Middle East oil.

Which places the “Great moral challenge of our generation” in perspective.

Andrew Glikson does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

This article was earlier published at The Conversation.

Rabu, 22 Mei 2013

Is the permafrost's integrity breaking down?

The chart below shows very high methane levels over Antarctica in April and May 2013. High levels of methane over Antarctica were recorded before in 2013, as described in an earlier post at the methane-hydrates blog.

Meanwhile, a methane reading of 2475 ppb was recorded on April 26, 2013, appearing to originate from the Himalayan Plateau, as illustrated by the image below.

Recurring high readings could indicate that methane is bubbling up through the permafrost, both in Antarctica and on the Himalayan Plateau.

Loss of the integrity of the permafrost is particularly threatening in the Arctic, where the sea ice looks set to disappear within years, resulting in huge albedo changes in summer. Decrease of surface reflectivity results in increases in absorption of energy from sunlight and decreases in shortwave radiation in the atmosphere. The latter results in lower photo-dissociation rates of tropospheric gases. Photo-dissociation of the ozone molecule is the major process that leads to the production of OH (hydroxyl radical), the main oxidizing (i.e., cleansing) gas species in the troposphere. A 2009 NASA study projects this to lead to a decrease in OH concentrations and a weakening of the oxidizing capacity of the Arctic troposphere, further increasing the vulnerability of the Arctic to warming in case of additional methane releases.

Levels of greenhouse gases such as carbon dioxide and methane are already very high in the Arctic atmosphere, while large quantities of black carbon get deposited on snow and ice, further contributing to the albedo changes. This threatens to result in rapid summer warming of many parts of the Arctic Ocean with very shallow waters. Additionally, rivers can bring increasingly warm water into those shallow seas in summer, adding to the threat that heat will penetrate the seabed that contains huge quantities of methane.

Above image, earlier included in an animation at the Arctic-news blog, shows methane concentrations on January 23, 2013, when a reading of 2241 ppb was recorded in the Arctic.

Analysis of sediment cores collected in 2009 from under ice-covered Lake El'gygytgyn in the northeast Russian Arctic suggest that, last time the level of carbon dioxide in the atmosphere was about as high as it is today (roughly 3.5 to 2 million years ago), regional precipitation was three times higher and summer temperatures were about 15 to 16 degrees Celsius (59 to 61 degrees Fahrenheit), or about 8 degrees Celsius (14.4 degrees Fahrenheit) warmer than today.

As temperatures rose back in history, it is likely that a lot of methane will have vented from hydrates in the Arctic, yet without causing runaway warming. Why not? The rise in temperature then is likely to have taken place slowly over many years. While on occasion this may have caused large abrupt releases of methane, the additional methane from such releases could each time be broken down within decades, also because global methane levels in the atmosphere were much lower than today.

In conclusion, the situation today is much more threatening, particularly in the East Siberian Arctic Shelf (ESAS), as further described in the earlier post methane hydrates.

Above post is an extract of the full post at the methane-hydrates blog.

Selasa, 12 Maret 2013

The worst-case and - unfortunately - looking almost certain to happen scenario

Aaron Franklin

By Aaron Franklin

I have asked for the world leading climate and arctic scientists I have been working with at AMEG, and Arctic-News to review this, and if they don't agree with any part or the end conclusion to please inform me immediately.

As yet no-one has come forward, with any criticisms whatsoever, only agreement that this is what we are very likely facing.

If we don't act very fast and the Arctic sea ice goes...

Up till now the sea ice, and the pool of low salinity meltwater left on the surface of the arctic ocean from it melting has blocked the warm Gulf stream from getting any further than the strip of coast with a shallow continental shelf seabed, around the north of Europe and western Russia as far as the islands and peninsulars that jut north from the west Siberian coast.

High salinity, warm gulfstream water of tropical origin does not mix freely with cold low density low salinity meltwater. It mixes and sinks in a sheet current at the boundary between these two bodies of water.

This has not caused any big problems so far as it has been happening along a fairly short boundary above shallow continental shelf and the downwards mixed flow is slowed by flowing over the the shelf before it sinks into the deep polar basin.

However... the meltpool on top of the Arctic ocean has been getting smaller every year and if we let the gulf stream get any further than it has to date then it will most likely continue all the way along the east Siberian coast, combine with the warm bering strait inflow, encircle the whole polar basin. Or at least most of it, if there is still enough multi-year sea-ice damming up against the west coast of the north Canadian archipelago to stop it getting to the extreme Canadian side of the arctic ocean.

There probably isn't enough multiyear seaice left to do this anyway and it won't make any differency to the overall outcome anyway, which is....

Encouraged by the anti-clockwise, low level Arctic atmospheric wind vortex (the low pressure system that is usually in place over the nth pole) the gulf-stream loop will accelerate, forming a mixing vortex (whirlpool), first sucking down any remaining surface meltwater pool to deep polar ocean, along a long circular front above the deep polar basin.

As this is happening the Gulf stream and Bering strait warm water inputs will accelerate dragging ever warmer water in, and the entire Arctic ocean near surface region will flood with warm high salinity water at up to 12C or even higher.

This will eliminate any chance of the arctic ocean refreezing in winter. And:

The average 12C temperatures of the upper layer of the polar ocean will be sending a big thermal pulse down through the East Siberian Arctic Shelf and other shallow submarine permafrosts in the arctic. This pulse propagating fast through liquid water in cracks and methane eruption vents. The hydrate layers containing over 1000 billion tons C of methane at the bottoms of these permafrosts will be destabilising, bottom up, when that thermal pulse pins them between itself and rising geothermal heat.

The ESAS and other Arctic shelf Methane Hydrate reefs will be fizzing like an alka-seltzer in a glass of warm water, and the wind-turbulated open water will mean lots of that methane getting into the atmosphere and spiking global warming.

As the sun has set for the north polar winter at this point, the northern Alaskan, Siberian, and Canadian tundras will cool rapidly as usual. But this time the warm surface of the polar ocean will be releasing water vapour and this warm low density air/water vapour mixture will rise, accelerating the polar low into a very deep arctic storm system, very likely far stronger than any we've ever seen.

This will erupt warm water vapour bearing air high into the troposphere, and stratosphere above the pole and this will suck in the cold air from over Alaskan, Siberian, and Canadian tundras, drawing in air from further south and causing heavy winter rainfall rather than light snowfall. (usually in winter polar highs are dominant and descending cold dry air from these flows out over the Alaskan, Siberian, and Canadian tundras).

The tundra permafrosts will now be drenched in large volume rainfalls. The warm lakes and bogs all over them will be drilling through the permafrost, and lots of the around 1700 billion tons C of organic carbon locked up in the land permafrost will be flooding into the Arctic Ocean from Siberia, Alaska and North Canada. And getting sucked down the polar plughole. Lots will be getting released into the air as methane and carbon dioxide, and spiking global warming.

The donut-shaped circulation pattern sitting like a crown over the Arctic circle will start drawing down stratospheric air from further south.

Sometime soon, very probably in the nest northern summer monsoon season...

-At this point the extra methane, ozone, water vapour, and the loss of sea ice reflecting sunlight back into space will together be producing about 3x present day global warming effect.

and...

The jetstreams that are formed by warm moist air rising from the equator, dumping that moisture as heavy tropical rain in the tropics usually descend in the subtropical desert belts that circle the globe. They like cogs intermeshing will connect with the polar donut, drawing the summer monsoon north over the subtropical desert belts and building rapidly to tropical rainfall levels over the worlds deserts.

The dry descending air from the equatorial and north polar origin tropospheric flows and jetstreams will turn the temporate zones of the northern hemisphere into deserts in one year.

The ex tundra boglands will start to dry out. Its been learnt that when you thaw and soak permafrost peats, waking up the frozen bacteria. Then drain them....

-Significant quantities of Nitrous Oxide (N2O) start being emitted. Another "super-greenhouse" gas, with its own special radiative absorption band.

-With even more water vapour, more methane, more N2O, more ozone being produced by the methane, less SO2 forming clouds because methane destroys it....

Global warming will start to spike very high.

What happens maybe very quickly now is that an equatorial origin jetstream will either detach from its mode of descending at the new temporate zone deserts and form a new anticyclone most probably over greenland, or the anticyclone from that jetstream will migrate north from the subpolar tundras over North Canada.

Either way this special anticyclone with a very big future, will winch its way around the polar low in the new easterly "tradewinds belt" where the tundras and boreal forests are now. It will probably end up over the Beaufort sea, north of Alaska and recruiting more stratospheric jetstreams of Equatorial origin, quickly grow in strength. It will start a new clockwise ocean surface vortex in the Beaufort sea region, and if any iceflows and cold meltwater are still trapped against the west coast of the Canadian Archipelago.....

They will get sucked into this new clockwise vortex and it will love feeding on them and growing just like in the first anticlockwise vortex described above.

The new polar super anticyclone will out compete the previous polar super cyclone by one by one recruiting all the equatorial and tropical origin jetstreams, and become a, for any relevance to us, permanent, extremely powerful anticyclone over the whole polar ocean.

The new clockwise polar ocean vortex will be accelerated by the clockwise anticyclonic low atmospheric vortex. There will likely be lots of Glacier calved icebergs from Greenland, stuck against the west coast of the Canadian Archipelago. It will love gobbling, melting, and feeding on those.

It will steal the deep subduction from, and outcompete and swallow the previous anticlockwise polar ocean vortex.

Powering up this vast whirlpool, will suck in ever increasing flows of Atlantic and Pacific water, flooding the Arctic ocean with more and more tropical water. It will shovel more and more warm surface water like a wedge into a new intermediate temperature, high salinity layer, building between the tidal mixed zone and the surface mixed layer .

This intermediate layer is said to be the mechanism that produces anoxic oceans in past super-greenhouse/ anoxic ocean events. And this will happen fast because....

The tundra permafrosts will be seasonal deserts, but much warmer now. In summer they will be drenched by tropical temperature and volume rainfalls, hammered by cold fronts, supercell storms and tornados spitting off the high lattitude Megacyclones. The warm lakes and bogs all over them will be drilling through the permafrost, and more of the around 1700 billion tons C of organic carbon currently locked up in the land permafrost will be flooding into the arctic ocean from Siberia, Alaska and Nth Canada. And getting sucked down the polar plughole. More methane and CO2 will be making it into the atmosphere

In winter the ex tundras will dry out. Releasing yet more N2O and CO2.

Global Warming will spike through the roof.

And...

The by now over 20 degrees Celsius temperatures of the upper layer of the polar ocean will be sending a massive thermal pulse down through the East Siberian Arctic Shelf (ESAS) and other shallow submarine permafrosts in the arctic. This pulse propagating fast through liquid water in cracks and methane eruption vents. The hydrate layers containing over 1000 billion tons C of methane at the bottoms of these permafrosts will destabilise fast, bottom up, when that thermal pulse hits them. Quite possible the pressure building up under these shelves, most particularly the ESAS will shatter them and release most of the hydrate methane, free methane, and undecomposed organic carbon, they are holding very fast indeed. Best estimate around 2750 billion tons C total in shallow submarine arctic permafrosts.

Kinda like a warm well shook champagne bottle when you pop the cork.

Lots of this methane will hit the atmosphere.

With even more water vapour, more methane, more N2O, more ozone being produced by the methane, less SO2 forming clouds because methane destroys it....

Ballpark Chart for near filling of all relevant Radiative Absorption bands

We'll have a greenhouse effect like the earth has not seen before in its 4.5 billion years of existence.

What REALLY concerns me looking at this chart is how much it would take going from this point to the Tipping Point for the Venus syndrome.

The situation in this chart would lead to a lot more stratospheric water vapour feedback. That could start to run away until the equatorial oceans boil, and there's no stopping things from there.

Lots of methane will get sucked down the Arctic plughole into the new anoxic intermediate ocean layer.

Archer 2007 states that 1000 billion tons C of methane (and/or other dissolved organic carbon) is sufficient to remove all oxygen from the worlds oceans. That won't take long.

The polar ocean vortex might eventually stop. The momentum in ocean circulation, both deep and in surface gyres, combined with wind driven surface currents won't let this happen fast.
In maybe 300-1000yrs a second even larger methane release will occur, as the heat from the surface reaches the deep sea bed. The deep sea Methane hydrates are estimated as between 5000 and 78 000 billion tons C of methane. That will not be nice at all, but there may be nothing left but bacteria well before then anyhow.
The tropical/subtropical origin MegaCyclones to polar Mega AntiCyclone jetstreams with low atmosphere return system will most probably stick around for at least 100 000 years.
The previous anoxic supergreenhouse/anoxic ocean events did have stalled ocean circulation, and the only way that they could have had 27C polar ocean temps like they did is by the Equatorial-Polar jetstream circulation mode described above.
The most serious previously, the end-permian had no polar basin, oceanic/ atmosphere circulation, turbine pump "beartrap" for the planetary eco-geosphere to put its foot in. Neither did the PETM and Elmo supergreenhouse/anoxic ocean events, the most serious of the last 100+ million years, the polar basin was landlocked for those.
Never before could the earth have had as much polar permafrost methane and carbon as it does now.

I hope this explains to everyone the urgency and seriousness of the current situation, and why we need to act with overwhelming force to stop the arctic sea-ice going this year.

If we don't act fast now all this could very well unfold unstoppably in the next year or two. Can't see it taking much longer than 10 or 20 at the most.

Senin, 21 Januari 2013

Call for High-Level Risk Assessment

There is a rapid and accelerating decline of Arctic and Far North snow and summer albedo cooling, with the Arctic summer sea ice past tipping point. Several potentially catastrophic (to huge human populations and all future generations) Arctic changes are happening decades ahead of model projections. This is potentially a United States and world food security emergency, and an Arctic methane feedback planetary emergency. The pace is outstripping the capacity of the international published climate modeling science to assess the risks. The climate science assessment process is unable to rapidly assess all the risks and the combined risk of all risk factors.

In 2008 and again in 2012, after the large drops in summer sea ice extent, James Hansen made a public statement that the world is a state of planetary emergency. Starting in 2006 John Holdren presented the scientific evidence that we are beyond dangerous interference with the climate system and challenged to prevent catastrophic interference.

The problem is that the summer sea ice cover, Arctic frozen methane and world food security are not projected by the assessments to be a serious problem for many decades. This despite the fact that for many years scientists have warned that the loss of the Arctic summer sea ice cover would result in a large boost in warming, and that this would cause the release of the vast Arctic stores methane to start. Scientists call the Arctic summer sea ice cover the air conditioner of the entire Northern hemisphere.

We are seeing a multi-year heat and drought situation affecting the world’s top Northern hemisphere food producing regions of the U.S., Russia and China. Increasing drought affecting these regions is projected, but the situation developing right now may be due to the loss of Arctic albedo affecting the weather of the normally temperate climate zone of the Northern hemisphere, on top of sustained direct greenhouse gas warming.

All Arctic sources of global warming vulnerable methane are emitting more methane with the amplified increasing Arctic warming. This includes the destabilization of the methane that is contained in the form of hydrates and free gas in the Arctic seabed. Atmospheric methane is now on a renewed sustained increase - this time due to planetary methane emissions.

Without getting a rapid risk assessment of this situation there seems no hope of any measures to address it. The UN climate negotiations for world emissions reductions are on hold till 2020. Emissions have never been higher and are increasing and the only plan is to burn more fossil fuels and of the worst kind.

Leading climate experts say we are now committed to a warming over 2C, probably to 3C and possibly 4C. We are on track for 6C by 2100. Even an all out emergency scale response would not see any reduction of atmospheric GHGs for many decades.

We call for an urgent high-level risk assessment to capture all these adverse trends and situations. An Arctic climate risk assessment is needed to address the unprecedented risks that are threatening the security of the U.S., the Northern hemisphere and the world at large, and the well-being of both current and future generations.

Above call for a high-level risk assessment was initiated by Dr. Peter Carter of the Climate Emergency Institute. Please try and improve this message and see that it finds its way to the people who need to see this and take action, including leading climate scientists, doctors, politicians and those holding public office positions with a duty of care.

Selasa, 25 September 2012

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