It is a familiar story in the climate change debate. The US government is at odds with the rest of the world and, despite criticism, wants other countries to change their minds and fall in line behind Uncle Sam.

This time, the tale comes with an unexpected twist. This weekend, the US will warn that the threat from climate change to the survival of the polar bear is so great that the world must grant it the highest possible protection.

At the meeting of the international body that regulates trade in animals, the US will push for a total ban on the sale and movement of polar bear products that are used for furs, rugs and taxidermy. Melting sea ice in the Arctic will kill thousands of bears in coming years, the US says, and continued commercial trade must not be allowed to make the situation worse. Other countries, including US neighbours and keen polar bear traders, Canada, disagree.

The US has put its proposal to the Convention on International Trade of Endangered Species (Cites), which meets every two-three years and tomorrow begins its 12-day meeting in Doha, Qatar. Governments from 175 countries will discuss dozens of such proposals, which could help determine the fate of, among others, elephants, tigers, rhinos and the world’s dwindling stocks of bluefin tuna.

“2010 is a key year for biological diversity,” said Achim Steiner, head of the United Nations Environment Programme, which runs Cites. “It is the year when the world was supposed to have reversed the rate of loss of our biodiversity. This has not happened. The international community must re-engage and renew its efforts to meet this goal. Cites is an important part of this response.”

The US wants polar bears promoted to Cites appendix I, which brings an automatic ban on trade. In its proposal it says: “Sea ice changes will likely negatively impact polar bears by increasing energetic demands of seeking prey. As changes in habitat become more severe and seasonal rates of change more rapid, catastrophic mortality events that have yet to be realised on a large scale are expected to occur.”

It adds: “A precautionary approach, which includes polar bears in Cites appendix I, is necessary to ensure that primarily commercial trade does not compound the threats posed to the species by loss of habitat.”

Biologists reckon there are 20,000 to 25,000 polar bears in the Arctic, spread across 19 geographical sub-populations. Last year the polar bear specialist group of the International Union for Conservation of Nature said that numbers in eight of these groups were declining, three are stable and one, a group of under 300 animals around Canada’s M’Clintock Channel, is increasing. The state of the other seven groups is unclear.

The US plan is backed by Egypt and Rwanda, but other nations, including Europe, are expected to vote against. Canada, which exports skins and products from about 300 polar bears legally shot each year, says the trade is insignificant compared to the threat of global warming.

There are also doubts about whether the polar bear meets the required criteria for appendix I listing. In its official response to the US proposal, the Cites secretariat recommend it is rejected. “The global population of polar bears does not appear to be small. The area of distribution of this species extends over several million square kilometres and is clearly not restricted at present,” it says. “There is insufficient evidence that the species has undergone a marked decline in population size in the wild large enough.”

The Cites meeting will also trigger a new round in a long-running debate about the sale of ivory harvested from African elephants. Trade in ivory was banned in 1989, though Cites has permitted one-off sales of government stocks from countries including Botswana, South Africa and Japan. The $20m raised from the sales were channelled towards elephant conservation, but critics say they encourage poaching and illegal trade.

Tanzania and Zambia will this year push to be allowed a similar sale of ivory stocks, though other African nations such as Ghana, Kenya and Mali have signalled they will vote against the plan. All proposals need a two-thirds majority to pass.

Other Cites proposals include moves to control unregulated trade in corals and sharks, including the porbeagle, spiny dogfish and three species of hammerhead, as well as the proposed ban on bluefin tuna trade.

“The marine theme of this year’s Cites conference is particularly striking,” said Willem Wijnstekers, Cites secretary-general. “Cites is increasingly seen as a valuable tool to achieve the target of restoring depleted fish stocks by 2015 to levels that can produce the maximum sustainable yield.”

Not all the proposals reflect shrinking biodiversity. Mexico and Egypt want to relax Cites controls on local species of crocodile they argue have recovered sufficiently in the wild.

Monaco has proposed adding the bluefin tuna to Cites appendix 1, which brings an automatic ban in trade.

The giant fish can grow to 3m and weigh more than half a tonne. Much sought after as a delicacy and for sushi, a single fish reportedly sold earlier this year for $120,000.

Populations in the Atlantic and Mediterranean have crashed in recent decades and there is no sign that efforts to introduce more sustainable fishing practices have slowed the decline. Scientists say stocks are about 15% of what they were before industrial fishing began.

The proposed change is backed by the US and Europe, which wants a 12-month delay on any trade ban. Japan has indicated it may opt out from Cites controls if it is passed. It wants bluefin conservation to be managed by regional fishery bodies and blames the fish decline on European countries for setting unrealistic quotas and ignoring illegal fishing.

Well, guess what?

Scientists from Alaska’s International Arctic Research Center, the Russian Academy of Sciences, and Stockholm University have published an article inScience magazine indicating the discovery of a startlingly large amount of methane coming from the East Siberian Arctic Shelf–methane that was thought to be frozen, in the form ofmethane clathrates. How much methane? An amount equivalent to the total of methane coming from the rest of the world’s oceans. The key paragraph, from the National Science Foundation press release:

They found that more than 80 percent of the deep water and more than 50 percent of surface water had methane levels more than eight times that of normal seawater. In some areas, the saturation levels reached more than 250 times that of background levels in the summer and 1,400 times higher in the winter. They found corresponding results in the air directly above the ocean surface. Methane levels were elevated overall and the seascape was dotted with more than 100 hotspots. This, combined with winter expedition results that found methane gas trapped under and in the sea ice, showed the team that the methane was not only being dissolved in the water, it was bubbling out into the atmosphere.

Okay, it’s a lot of methane… so what?

ethane–CH₄–actually traps a significantly greater amount of heat than does CO₂. The NSF article cites it as 30 times greater greenhouse impact than carbon dioxide, and I’ve seen references between 20x and 72x, depending upon how it’s measured. Regardless, this is a big difference, and the amount of methane frozen under the Siberian permafrost can be measured in the millions of tons (up to 70 billion tons across the entire permafrost region). If the East Siberian methane melts, it would be akin to tripling the amount of CO₂ in the atmosphere, raising temperatures around the world by 8-10° C, and arctic temperatures by 20° C by the end of this century. That would be very, very bad, like you-really-don’t-want-to-go-there bad.

It turns out, in fact, that one of the biggest mass extinctions in Earth’s history has been tied to a rapid methane clathrate melt.

You see, the East Siberian methane is fairly close to the surface; as temperatures rise, methane clathrates deeper down will start to melt, making temperatures go up faster, melting even deeper stores of methane ice, and so on. It’s a runaway feedback loop–what some folks call the “clathrate gun.” This whole process would take just a few decades. Melting methane clathrates are pretty much the scariest of the so-called “tipping point” effects of anthropogenic global warming. We don’t need to burn every fossil fuel on the planet to make something awful happen, we just have to burn enough to start to thaw out methane ice, and natural processes take it from there.

There are two immediate questions we need to answer:

1) Does this study show us that there’s a runaway methane event underway? The short answer is no. This is the first detailed study of methane concentrations in the region, so we don’t know for sure whether the methane concentrations are increasing slowly, increasingly quickly, or not increasing at all. That the amount of methane is so disproportionate (and is higher than amounts found in ice core samples from thousands of years ago) suggests that something is happening, but in my expert opinion, it’s not yet time to panic.

2) What can we do about it? It depends on how fast the methane clathrates are melting. If they’re melting slowly, our best bet would be to do everything humanly possible to cut anthropogenic carbon emissions to zero. We have to avoid pushing the climate into a runaway methane tipping point; the faster we cut our carbon emissions, the better chance we have of avoiding this catastrophe.

If the methane clathrates are melting quickly, however, the story gets more complicated. Although we’d want to get to zero as quickly as we could, because of the carbon we’ve already put into the atmosphere–which keeps warming us–and because of ocean thermal inertia–the pace at which the ocean warms up and cools down–we’d still see another few decades of warming. Simply going to zero wouldn’t be enough to avoid a methane runaway, if the clathrates are already melting quickly.

This is where the desperation moves come in. It’s quite likely that, for many people, a clathrate melt would mean geoengineering goes from being a “Plan B” to “Plan Ohmygodyouhavetostartdoingthisnow.” At the very least, we would need to step up the study of how temperature-management geoengineering would affect the overall environment, because there’s a very good chance we’ll want to use it.

We also would want to look at ways to remove the methane from the oceans and the atmosphere. I have a long post over at my main blog detailing what this would entail, but it’s enough to say here that while it wouldn’t be easy, it looks like it might be possible. This would have its own side-effects, too, of course… but probably not as bad as a mass extinction event.

The big lesson here is that the Earth’s environment is a fantastically complex system, and changing one parameter–in this case, the temperature–can have effects far beyond what a simple straight line extrapolation would suggest. If we’re lucky, follow-up studies will show that the methane emissions are either stable or only growing slowly, giving us enough time to upgrade how we live without having to do anything risky. But even if this is the case, good luck can’t hold on forever.

Arctic not governed by international legal norms

The consequences of this are more and more cruise ships, the possibility of offshore drilling and prospects for the Northwest passage, all of which are increasing sea traffic. This is not governed by existing maritime law on safety or pollution standards as the Arctic is not governed by international legal norms and regulations.

As Diana Wallis puts it “there are many changes taking places in the Arctic in terms of the opening of sea routes,  availability of many different natural resources, citizens can travel up to the Arctic as tourists, there is no proper rescue facility in the Arctic and there are many issues with Arctic related that effect EU citizens”.

“18th century sovereignty, nationalistic type arguments”

On top of this is the fact that the arctic is thought to contain 20% of undiscovered oil and gas reserves.

The strategic importance of the Arctic was shown in 2007 when a Russian flag was planted on the seabed. Three EU states are Arctic nations – Sweden, Finland and Denmark and the EU has close ties with another two, Iceland and Norway.

Diana Wallis is aware of these political developments: “There are so many issues going on that show the retreat into what I would call 18th century sovereignty, nationalistic type arguments. There was always a concept that the Arctic could be an area that was treated differently. It can’t be international in the sense of the Antarctic, because we have people and nation states in the Arctic.”

In particular she is referring to the native Inuit who are threatened as the ice is getting too thin for their sledges. Polar bears, walruses and foxes are also seeing habits vanishing.

“Arctic issues fall on environment, fisheries and research”

Ms Wallis wants a forthcoming European Commission communication to lay out ways the EU can develop its own standalone Arctic policy.  ”Some of us have argued for instance that it should be a specific commissioner that is able to pull together and have a responsibility for Arctic issues. Because the problem is that Arctic issues concern the environment, fisheries and research. Do you give it to the High Representative (for foreign affairs)? Because on the one hand it is external affairs, on the other level it clearly involves home issues. This is important to all EU citizens,” she told us.

There has been a lot of press coverage of a new paper in Science this week called “Extensive methane venting to the atmosphere from sediments of the East Siberian Arctic Shelf”, which comes on the heels of a handful of interrelated methane papers in the last year or so. Is now the time to get frightened?

No. CO₂ is plenty to be frightened of, while methane is frosting on the cake. Imagine you are in a Toyota on the highway at 60 miles per hour approaching stopped traffic, and you find that the brake pedal is broken. This is CO₂. Then you figure out that the accelerator has also jammed, so that by the time you hit the truck in front of you, you will be going 90 miles per hour instead of 60. This is methane. Is now the time to get worried? No, you should already have been worried by the broken brake pedal. Methane sells newspapers, but it’s not the big story, nor does it look to be a game changer to the big story, which is CO₂.

For some background on methane hydrates we can refer you here. This weeks’ Science paper is by Shakhova et al, a follow on to a 2005 GRL paper. The observation in 2005 was elevated concentrations of methane in ocean waters on the Siberian shelf, presumably driven by outgassing from the sediments and driving excess methane to the atmosphere. The new paper adds observations of methane spikes in the air over the water, confirming the methane’s escape from the water column, instead of it being oxidized to CO₂ in the water, for example. The new data enable the methane flux from this region to the atmosphere to be quantified, and they find that this region rivals the methane flux from the whole rest of the ocean.

What’s missing from these studies themselves is evidence that the Siberian shelf degassing is new, a climate feedback, rather than simply nature-as-usual, driven by the retreat of submerged permafrost left over from the last ice age. However, other recent papers speak to this question.

Westbrook et al 2009, published stunning sonar images of bubble plumes rising from sediments off Spitzbergen, Norway. The bubbles are rising from a line on the sea floor that corresponds to the boundary of methane hydrate stability, a boundary that would retreat in a warming water column. A modeling study by Reagan and Moridis 2009 supports the idea that the observed bubbles could be in response to observed warming of the water column driven by anthropogenic warming.

Another recent paper, from Dlugokencky et al. 2009, describes an uptick in the methane concentration in the air in 2007, and tries to figure out where it’s coming from. The atmospheric methane concentration rose from the preanthropogenic until about the year 1993, at which point it rather abruptly plateaued. Methane is a transient gas in the atmosphere, so it ought to plateau if the emission flux is steady, but the shape of the concentration curve suggested some sudden decrease in the emission rate, stemming from the collapse of economic activity in the former Soviet bloc, or by drying of wetlands, or any of several other proposed and unresolved explanations. (Maybe the legislature in South Dakota should pass a law that methane is driven by astrology!) A previous uptick in the methane concentration in 1998 could be explained in terms of the effect of el Nino on wetlands, but the uptick in 2007 is not so simple to explain. The concentration held steady in 2008, meaning at least that interannual variability is important in the methane cycle, and making it hard to say if the long-term average emission rate is rising in a way that would be consistent with a new carbon feedback.

Anyway, so far it is at most a very small feedback. The Siberian Margin might rival the whole rest of the world ocean as a methane source, but the ocean source overall is much smaller than the land source. Most of the methane in the atmosphere comes from wetlands, natural and artificial associated with rice agriculture. The ocean is small potatoes, and there is enough uncertainty in the methane budget to accommodate adjustments in the sources without too much overturning of apple carts.

Could this be the first modest sprout of what will grow into a huge carbon feedback in the future? It is possible, but two things should be kept in mind. One is that there’s no reason to fixate on methane in particular. Methane is a transient gas in the atmosphere, while CO₂ essentially accumulates in the atmosphere / ocean carbon cycle, so in the end the climate forcing from the accumulating CO₂ that methane oxidizes into may be as important as the transient concentration of methane itself. The other thing to remember is that there’s no reason to fixate on methane hydrates in particular, as opposed to the carbon stored in peats in Arctic permafrosts for example. Peats take time to degrade but hydrate also takes time to melt, limited by heat transport. They don’t generally explode instantaneously.

For methane to be a game-changer in the future of Earth’s climate, it would have to degas to the atmosphere catastrophically, on a time scale that is faster than the decadal lifetime of methane in the air. So far no one has seen or proposed a mechanism to make that happen.

A new report by a leading European think-tank says China is “paying increasing attention to the consequences of the melting of the ice in the Arctic” and positioning itself for an influential role in the emerging realm of polar geopolitics, says vancouversun.comThe “groundbreaking” study by the Stockholm International Peace Research Institute, partly funded by the Norwegian government, also revealed that Canada has already engaged in bilateral meetings with the Asian superpower to confront potential issues arising from the recent record-setting retreat of Arctic sea ice, which has raised the prospect of increased shipping and oil development in the region.

The report, released Monday, quotes one of China’s top Arctic experts as saying: “Circumpolar nations have to understand that Arctic affairs are not only regional issues but also international ones.”

Authored by the institute’s China specialist Linda Jakobson, the study — titled “China Prepares For an Ice-Free Arctic” — distils dozens of interviews with China’s leading polar scientists and policy-makers.

“To date China has adopted a wait-and-see approach to Arctic developments, wary that active overtures would cause alarm in other countries due to China’s size and status as a rising global power,” the report notes. “However, in recent years Chinese officials and researchers have started to also assess the commercial, political and security implications for China of a seasonally ice-free Arctic region.”

China’s increasing attention toward Arctic issues is evident in its recent effort to obtain permanent observer status with the Arctic Council, an eight-nation forum that includes Canada and the four other Arctic Ocean coastal states — Denmark, Russia, the U.S. and Norway — as well as Sweden, Iceland and Finland.

The question of China’s inclusion on the margins of the forum, along with that of the European Union, was postponed recently — in part because of Canada’s objections to the EU’s controversial ban on commercial seal products.

“We are aware of China’s growing interest in polar issues, both in the Arctic and Antarctic,” Foreign Affairs spokeswoman Catherine Loubier told Canwest News Service on Monday. “Past discussions with China were largely centered around an exchange of information on various scientific endeavors.”

Two of Canada’s leading Arctic experts say they are impressed with China’s commitment to investing in Arctic science and both say it’s clear the Asian giant plans to respect the territorial sovereignty of the Arctic coastal countries while angling for a greater role in polar research, Arctic governance and, ultimately, economic development.

“The Chinese are about to emerge as a major Arctic power,” says University of Calgary political scientist Rob Huebert, who travelled to Beijing and Shanghai last week for a Sino-Canadian forum on Arctic issues and to visit China’s main polar research institute.

“They are investing heavily to set themselves up for Arctic science,” said Huebert, noting that China is currently building what will be the world’s largest icebreaker for polar research. “China’s prosperity depends on maritime shipping. They clearly want to get an understanding of the possibility of new trade routes.”

University of British Columbia professor Michael Byers, author of Who Owns The Arctic?, said the reassuring tone of the Swedish report “contradicts some of the fear mongering” surrounding China’s interest in the Arctic and its resources.

“It shows how countries around the world are gearing up to take advantage of the melting sea ice,” Byers adds, “and how Canada needs to get its act together” to prepare for increased shipping in the Northwest Passage and potential oil exploration throughout the North.

On Saturday, the federal government announced details of its plans to more strictly regulate marine traffic in Canada’s Arctic waters, implementing by July 1 a mandatory ship-tracking system for all large vessels — foreign and domestic — that travel through the Canadian Arctic archipelago.

The current voluntary registry has been the target of critics for years as a lax system that could lead to environmental disasters, tourism tragedies and even terrorist activity in the Arctic.

Precisely how the increasingly open Arctic waters will be regulated and governed in the future remains unresolved. While claims for potentially oil-rich undersea territory are being peacefully worked out under a UN treaty, the five nations with Arctic Ocean coastlines recently rankled northern aboriginal groups and the three non-coastal members of the Arctic Council by excluding them from a planned Arctic Summit later this month in Chelsea, Que., near Ottawa.

Global warming is a contentious issue again because skeptics have pointed out inconsistencies with the data scientists are using to measure how much humans are impacting the environment, says taintedgreen.com

Setting that debate aside for a moment, scientists have discovered that somewhere around 7 teragrams of methane, a potent greenhouse gas, has been released each year from the East Siberian Arctic Shelf. That’s around 7.7 million tons of methane, and the data was aggregated from 5,000 locations. Sound credible?

In a situation like this the argument over who is causing global warming – man or nature – becomes almost irrelevant. It’s important for us to understand how that much greenhouse gas drifting into the atmosphere will affect the climate. Our ability to adapt or prevent that shift in climate may determine the next step in our collective bloodline.

Right now that gas is trapped in ice within something scientists call “methane hydrates”. Its depth and freezing temperatures keep it contained but destabilization has put those structures at risk. Natalia Shakhova from the University of Alaska says “this is a little alarming. We do not know how massive or sudden this outburst was. We don’t know how many there were. We don’t know how close to the equilibrium we are. A lot of questions are still open.”

In the debate over human-caused global warming, aka “climate change,” perhaps the most overused and exploited symbol is the polar bear. We are bombarded almost daily with images of polar bears struggling to stay afloat on comparatively tiny chunks of arctic ice. We hear about their struggles to find food and shelter for themselves and their young.Climate change, we are told, will be the death of the mighty polar bear.

However…

Funny thing. It seems that climate change was responsible for the birth of species. The discovery of an ancient jawbone at Poolepynten on the Arctic island of Svalbard by Professors Olafur Ingolfsson, of the University of Iceland, and Oystein Wiig, of the University of Oslo has yielded new insight into the evolutionary history of polar bears.

Previous estimates as to the date of origin of the species ranged from 50,000 to one million years ago. A series of DNA tests on the jaw bone has revealed that polar bears are much closer kin to brown bears than previously believed, and they’re especially similar to a population of brown bears in the “ABC Islands” of Alaska.

The age of the jawbone fossil and other evidence makes a strong case that the polar bear evolved from brown bears trapped in the onset of an ice age that began about 190,000 years ago. The fossil is believed to be between 110,000 and 130,000 years old. This also means that polar bears likely have already survived at least one period of global warming that took place approximately 115,000 years ago.

This notion does come with a caveat:

Professor Chris Stringer, of the Natural History Museum in London, an expert in ice ages, said: “Early polar bears would not have had all the specialisations of modern animals and we know nothing about their behaviour. Living through a warm period back then does not mean they are resilient to climate change now.”
—TimesOnline

Interesting to note however, that his tone is one of gloom and doom for modern polar bears even while admitting that “… we know nothing…”

Then again, knowledge, or the lack thereof, has never been an impediment to climate alarmists. According to a study by American and Canadian scientists in 2006, the shrinking ice pack was leaving polar bears less and less space in which hunt seal. As a result, they claim, polar bears were resorting to cannibalism. Such a proclamation doubtlessly sent climate change true believers and animal activists into a frenzy of demands for new legislation to save the hapless bears.

But…

Inuit leader Jose Kusugak, the president of the Kivalliq Inuit Association, told reporters: “A male polar bear eating a cub becomes a big story and they try to marry it with climate change and so on. It becomes absurd – when it’s a normal, normal occurrence.”
—TimesOnline

And…

“Both Inuit and scientific knowledge show that cannibalism in polar bears happens, and it probably always has,” said Steve Pinksen, director of policy and legislation for Nunavut’s Department of Environment.

The concern over cannibalism comes after a tourist group witnessed adult male bears attacking cubs for food. There have been at least eight reports of similar sights from Churchill, [Manitoba]. The photos accompanying stories on the issue show bright-red remains strewn across blankets of snow.

Mr. Pinksen, however, called the incidents an “act of nature,” and said the public reaction has been taken out of proportion.
—Signs of the Times News

Stop the presses!

This is a classic example of what I’m talking about. A few isolated incidents of people stepping out of their normally well-insulated lives and seeing nature at its most brutal results in the notion that a catastrophe is occurring within the polar bear population. This is the kind of knee-jerk reaction that the environmentalists feed on to push public opinion in directions that work to their advantage. Happens every day.

Pinksen continues:

“Maybe if you’re sitting in an armchair in the city somewhere these pictures would be a shock, but people up here see these things all the time,” he said, adding residents that are out hunting animals for food, clothing and income have seen evidence of these attacks in the past. A bear eating a bear is not a pretty picture, but nature is not really a pretty thing all the time,” Mr. Pinksen said.
—Signs of the Times News

In short, the fact that polar bears sometimes eat their young isn’t news. Other predators are known to eat their young as well. Male African lions for example, will eat the cubs sired by competing males to protect the dominance of their own bloodline. Fears that polar bear cannibalism will contribute to the death of the species are greatly exaggerated and based upon false assumptions and the politics of shameless opportunism.

Another assertion by leftist environmentalists is that polar bears are drowning in great numbers due to the melting ice, and that this of course will contribute to the eventual extinction of the species. According to various observations, polar bears are having to swim farther than ever before to reach sources of food, and many of them drown or die of hypothermia in the open seas.

According to the new research, four bear carcases were found floating in one month in a single patch of sea off the north coast of Alaska, where average summer temperatures have increased by 2-3C degrees since 1950s.

The scientists believe such drownings are becoming widespread across the Arctic, an inevitable consequence of the doubling in the past 20 years of the proportion of polar bears having to swim in open seas.
—TimesOnline

That these bears died in search of food is certainly a sad occurrence. But is man at fault here? According to many credible scientists, the answer is a resounding “NO.”

Is the Arctic ice melting? Yes, although there is some debate as to the rate of melt vs. the rate of refreezing. Most agree that there has been a decrease in total ice coverage since the early 1970’s. Climate alarmists of course would have us believe this is due to human activity. The hacked e-mails from East Anglia strongly suggest otherwise. How does one trust the science behind temperature monitoring stations when many of those stations were located (perhaps intentionally?) in areas affected by unnatural heat sources? One of them was even located near an industrial incinerator. Accurate science? Hardly. But the most recent IPCC Climate Report was based on data taken from those weather stations.

Polar bears live much of the year on the Arctic sea ice and have become a symbol for environmental campaigners of the threat of global warming.

New research suggests the species was able to rapidly adapt at a time when Earth  was in the last stages of an ice age and was beginning to warm.

However, scientists have warned they may not be able to repeat this feat, should temperatures continue to rise.

‘Our results confirm that the polar bear is an evolutionarily young species that split off from brown bears some 150,000 years ago and evolved extremely rapidly,’ said Charlotte Lindqvist, from the University of Buffalo.

‘But now the polar bear may be more evolutionarily constrained because it is today very specialised; living on the edge of the Arctic ice, subsisting on a few species of seals.’

Dr Lindqvist’s team analysed mitochondrial DNA (which is passed down through female ancestors) from the jaw fossil. DNA contains the genetic instructions used in the development and functioning of all known living organisms.

‘But now the polar bear may be more evolutionarily constrained because it is today very specialised; living on the edge of the Arctic ice, subsisting on a few species of seals.’

Dr Lindqvist’s team analysed mitochondrial DNA (which is passed down through female ancestors) from the jaw fossil. DNA contains the genetic instructions used in the development and functioning of all known living organisms.

While scientists had known polar bears were descended from brown bears, there was debate over when the division occurred.

By comparing the DNA from the fossil, which was estimated at 110,000-to-130,000 years old, to DNA from modern polar bears and brown bears they were able to calculate when the types separated.

Material drilled from the jawbone show that 20,000 years after the split, the animal was already as big as a modern polar bear, ate a similar marine-rich diet and lived in similar regions. It suggests the polar bear was able to adapt in a relatively short time.

Polar bear fossils are rare since their remains are usually scavenged by other animals or sink to the bottom of the ocean. The specimen tested was found in Norway’s remote Svalbard archipelago in 2004 by an Icelandic geologist.

The latest findings have been published in today’s edition of Proceedings of the National Academy of Science.

The report comes as Russia prepares to sail a large oil tanker the entire length of its Arctic sea coast for the first time, opening a strategic energy trading bridge between European Russia and east Asia.

The findings of the Stockholm International Peace Research Institute’s paper indicate that the Arctic could emerge as another area in which China starts defining global strategic interests, following its increasing investments in Africa and moves to build a presence in the Indian Ocean.

SIPRI said the prospect of the Arctic being navigable during the summer had driven Beijing to allocate more funds for polar research, and scholars were increasingly pushing the government to develop an Arctic strategy.

“Because China’s economy is reliant on foreign trade, there are substantial commercial implications if shipping routes are shortened during the summer months each year,” the report said. It added that taking the northern route through an ice-free Arctic could shorten the trip from Shanghai to Hamburg by 6,400km compared with sailing through the Strait of Malacca and the Suez Canal. In addition, piracy-induced high insurance costs could be avoided.

The report said another potential strategic interest for China could be the extraction of the Arctic’s natural resources.

Linda Jakobson, author of the report, said although China had one of the world’s strongest polar research programmes, Beijing had yet to assess the economic and security implications of an ice-free Arctic as it was “wary that active overtures would [alarm] other countries due to China’s size and status as a rising global power”.

Sovcomflot, Russia’s state shipping company, will sail an oil tanker accompanied by nuclear-powered ice breakers from Vitino on the White Sea to Japan in July, in a pilot voyage marking the start of oil exports along the northern route.

Sergei Frank, chief executive of Sovcomflot, said the Arctic route would be a “floating pipeline”, gradually helping Russia re-orientate its oil and gas exports away from Europe towards more dynamic eastern markets, including China.

Mr Frank ruled out the possibility of Chinese container vessels using the route, citing unpredictable navigation conditions and high insurance rates. “It’s nonsense,” he said.

“China is particularly wary of Russia and whether it might demand high passage fees, which could erase some or most of the potential efficiency gains,” Ms Jakobson said.

Sovcomflot, already the world’s biggest owner of ice-class vessels, expects to corner the market in Arctic energy shipping as huge new oil and gas reserves are developed in Polar regions.

Mr Frank said Russia’s northern route would not be closed to foreign shipping companies but users would need to comply with Russian environmental and navigation rules.

Ms Jakobson added that the strategic situation in the Arctic was “much more complicated” than the Antarctic.

“China is aware that its size and rise to major power status evoke jitters but at the same time it is striving to position itself so that it will not be excluded from access to the arctic,” the report said.

The export-dependent structure of China’s economy means shorter routes to Europe and North America could have a massive impact, the report said, citing estimates that nearly half of gross domestic product could be reliant on shipping.

The Northern Sea Route could shave over 6,000 kilometres off some journeys, it added.

A shorter route would also allow China to shave the cost – and the risk – of shipping crude oil and other commodities from the Atlantic coasts of Africa and the Americas.

China is at some disadvantage in negotiations over the future of the area, because it has no Arctic coast. With only five littoral states, most of the rest of the world is in a similar situation of jostling for influence in a potentially vital area.

“Circumpolar nations have to understand that Arctic affairs are not only regional issues but also international ones,” the report quoted Guo Peiqing, associate professor at the Ocean University of China, as saying.

Beijing’s traditional diplomatic emphasis on the importance of respecting national sovereignty and “non-interference” in the internal affairs of other countries, will make it hard for it to question the territorial claims of arctic states.

So if China does not step up political research and expertise, it could be excluded from being a decisive power in the management of the area, the report quoted experts saying.

Traditionally China has had strong polar research capacities, with a string of university programmes and concerted efforts to build up international exchanges – but focused on issues like the environment and climate change.

Researchers and officials have only started to weigh up the political and commercial implications of ice-free shipping routes in recent years, the report said.

But there are risks as well to the melting of arctic ice. Chinese shipping firms will face “fierce competition”, its ports in lower latitudes could suffer, and current international laws do not favour China’s interests in arctic shipping, the report said, quoting an assessment by a Chinese specialist panel.

Even if a sea route does open up, it could be ruled out as a practical option by challenges including high insurance premiums, the danger from floating icebergs, shallow passages or high charges from Russia for passage through its waters.