Richard Galpin gets rare access to Russia's floating nuclear power station
Could the Arctic become a battleground over control of large reserves of oil and gas thought to lie under the Arctic Sea, or will there be co-operation in the polar region? This will be a question for politicians and experts from around the world as they meet in Moscow.
In a grimy shipyard in St Petersburg, an ugly hulk of red-painted metal sits floating in the dock.
On deck, workmen scurry back and forth, hammering, drilling and welding.
This strange construction, part ship, part platform, is unique and lies at the heart of Russia's grand ambitions for the Arctic.
When it is completed in 2012, it will be the first of eight floating nuclear power stations which the government wants to place along Russia's north coast, well within the Arctic Circle.
The idea is the nuclear reactors will provide the power for Russia's planned push to the North Pole.
Moscow is claiming more than a million square kilometres of extra territory in the Arctic, stretching from its current border in the Arctic Sea, all the way to the Pole.
'Complicated and dangerous'The territory includes an underwater mountain range called the Lomonosov ridge, a area which some Russian scientists claim could hold 75 billion barrels of oil.
This is more than the country's current proven reserves.
"These [floating nuclear power stations] have very good potential, creating the conditions for exploring the Arctic shelf and setting up drilling platforms to extract oil and gas," says Sergey Zavyalov, deputy director of the operating company, Rosenergoatom.
"Work in the Arctic is very complicated and dangerous and we should ensure there's a reliable energy supply."
He says each power station, costing $400m, can supply electricity and heating for communities of up to 45,000 people and can stay on location for 12 years before needing to be serviced back in St Petersburg.
And while initially they will be positioned next to Arctic bases along the North coast, there are plans for floating nuclear power stations to be taken out to sea near large gas rigs.
"We can guarantee the safety of our units one hundred per cent, all risks are absolutely ruled out," says Mr Zavyalov.
But many environmentalists are alarmed and warn of the consequences of a nuclear accident in the pristine and fragile Arctic environment.
As Russia builds the infrastructure needed to operate in the Arctic, its Polar explorers announced this week they were stepping up efforts to provide the scientific evidence needed to convince the United Nations that Russia's claim to the Lomonosov ridge is valid.
Artur Chilingarov, who three years ago used a mini-submarine to plant the Russian flag on the seabed under the North Pole, will lead another expedition next month which will launch a drifting research station in the region.
Russia needs to collect soil samples from the seabed to prove the Lomonosov ridge is part of the Russian landmass.
The government wants this research completed as quickly as possible because it's declared that the Arctic should be Russia's main source of oil and gas by 2020
And also because Canada is making a rival claim to the territory.
Compromise soughtBut Russian scientists believe it could take another 10 years before enough evidence is collected and already tensions with Canada are rising.
"Russia does not want conflict with the other countries surrounding the Arctic," says Vladimir Kotlyakov, honourary president of the Russian Geographical Society and an Arctic expert.
"But naturally nobody wants to give up their territory.
"So we will make a huge effort to hang on to the territory which we think belongs to Russia."
"Of course conflict is always possible, but I repeat that the politicians currently in power in Russia want compromise."
They may want compromise, but they are pursuing a dual-track policy, pushing forward on every front to ensure Russia is the dominant power in the region even before the UN makes a ruling on the territorial disputes.
Although Moscow denies it's setting up special military forces or bases to protect its interests in the Arctic, it is establishing a new coastguard under the control of the all-powerful intelligence agency, the FSB.
Richard Galpin gets on board an ice-breaking ship that would make it much easier for Russia to send oil and gas exports to Asia
And this summer a Russian oil-tanker made a record-breaking voyage through the Northeast passage, which runs along Russia's northern coast linking the Atlantic and Pacific oceans.
The state-owned tanker carrying 70,000 tonnes of oil destined for China, was the largest to sail through the passage from Murmansk to the Bering Strait, completing the journey in less than two weeks.
All this is made possible by the melting of the Arctic ice in the summer months.
The route along the Northeast passage from Russia to Asia which is now opening up, is many days quicker than the traditional route via Europe, the Suez Canal and around India.
Although the ships still need to be escorted by ice-breakers, it is a tantalising opportunity for Russia which wants to sell more oil and gas to energy-hungry countries like China.
With some scientists predicting that there may be no ice at all in the summer by 2030, Russian officials are confident the Northeast passage will become a major route for energy supplies to Asia.
"We believe that five or six months a year are now available [for sailing through the Northeast passage]," says Sergei Frank, the chief executive of the state-owned shipping company, Sovcomflot, whose tanker made the record-breaking voyage.
"And if we can build stronger and smarter ships and find the best routes, then we can enlarge this window a bit."
Next year Mr Frank is planning to send even bigger tankers through the passage.
And on the broader issue of who the Arctic belongs to, he has no doubt that Russia is the rightful owner.
"Your very famous prime minister Winston Churchill, had a very proper saying: Right or wrong, but it's my country.
"The first serious Russian expedition in this area was launched in the 16th Century.
"This is our home."
An international meeting to try to prevent the Arctic becoming the next battleground over mineral wealth is taking place in Moscow.
One quarter of the world's resources of oil and gas are believed to lie beneath the Arctic Ocean.
Russia, Norway, Canada, Denmark and the United States have already laid claim to territory in the region.
Although the summit is promoting dialogue, a Kremlin adviser said Russia would defend its national interests.
Melting ice capThe region's resources are rapidly becoming accessible due to the rapid shrinking of the polar ice cap.
End Quote Lev Voronkov Russian Arctic expertI think that we are doomed to co-operate in the Arctic. And military confrontation especially is completely counterproductive”
Senior Norwegian adviser Olaf Orpheum told the conference that nowhere else had seen "such dramatic changes in the surface of the Earth".
The race for the Arctic centres on an underwater mountain range known as the Lomonosov Ridge.
In 2001, Moscow submitted a territorial claim to the United Nations which was rejected because of lack of evidence.
Three years ago, a Russian expedition planted a titanium flag on the ocean floor beneath the North Pole in a symbolic gesture of Moscow's ambitions.
Law of the SeaAs evidence of the gathering momentum in the race for mineral resources, Russia has announced it will spend $64m (£40m; 48m euros) on research aimed at proving its case.
The man behind the 2007 polar expedition, Artur Chilingarov, has announced that he will attempt to launch a drifting research station next month.
Kremlin climate change adviser Alexander Bedritsky told reporters that Russia had a "strong chance" to win approval when it submitted its data to the UN in 2012-13.
Last week, Canada's foreign minister met his Russian counterpart in Moscow to discuss their competing claims.
Canada is likely to hand its file to the UN around 2013 and has said it is confident of its case.
Denmark plans to put forward its details by the end of 2014.
For the states involved in the territorial dispute, the key lies in obtaining scientific proof that the Lomonosov Ridge is an underwater extension of their continental shelf.
Under the UN Convention on the Law of the Sea, a coastal nation can claim exclusive economic rights to natural resources on or beneath the sea floor up to 200 nautical miles (370km) beyond their land territory.
But if the continental shelf extends beyond that distance, the country must provide evidence to a UN commission which will then make recommendations about establishing an outer limit.
Last week, Russia signed a treaty with Norway, ending a 40-year dispute over their maritime borders in the Barents Sea and Arctic Ocean.
Russian Arctic expert Lev Voronkov said the experience of the Cold War proved the need to work together.
"No one problem of contemporary Arctic can be resolved by one country alone. So that's why I think that we are doomed to co-operate in the Arctic. And military confrontation especially is completely counterproductive."
Russian President Dmitry Medvedev said last week that Nato's presence in the Arctic could raise additional problems.
| By Roger Harrabin BBC environment analyst |
 The new study used data from tree rings and ice cores |
The most alarming forecasts of natural systems amplifying the human-induced greenhouse effect may be too high, according to a new report.
The study in Nature confirms that as the planet warms, oceans and forests will absorb proportionally less CO2.
It says this will increase the effects of man-made warming - but much less than recent research has suggested.
The authors warn, though, that their research will not reduce projections of future temperature rises.
Further, they say their concern about man-made climate change remains high.
The research, from a team of scientists in Switzerland and Germany, attempts to settle one of the great debates in climate science about exactly how the Earth's natural carbon cycle will exacerbate any man-made warming.
Positive, negative
Some climate sceptics have argued that a warmer world will increase the land available for vegetation, which will in turn absorb CO2 and temper further warming. This is known as a negative feedback loop - the Earth acting to keep itself in balance.
But the Nature research concludes that any negative feedback will be swamped by positive feedback in which extra CO2 is released from the oceans and from already-forested areas.
The oceans are the world's great store of CO2, but the warmer they become, the less CO2 they can absorb. And forests dried out by increased temperatures tend to decay and release CO2 from their trees and soils.
Commenting in Nature on the new research, Hugues Goosse from the Université Catholique de Louvain in Belgium said: "In a warmer climate, we should not expect pleasant surprises in the form of more efficient uptake of carbon by oceans and land… that would limit the amplitude of future climate change".
 |  I don't think they can rule out that the positive feedback from the carbon cycle could become stronger in a significantly warmer climate  Tim Lenton University of East Anglia |
The IPCC's fourth assessment report had a broad range of estimates as to how far natural systems would contribute to a spiral of warming. The Nature paper narrows that range to the lower end of previous estimates.
The report's lead author, David Frank from the Swiss Federal Institute for Forest, Snow and Landscape Research, told BBC News that many of the calculations for the IPCC assessment report did not include an integrated carbon cycle.
He said that if the results his paper were widely accepted, the overall effect on climate projections would be neutral.
"It might lead to a downward mean revision of those (climate) models which already include the carbon cycle, but an upward revision in those which do not include the carbon cycle.
"That'll probably even itself out to signify no real change in the temperature projections overall," he said.
'Comforting'
The team's calculations are based on a probabilistic analysis of climate variation between the years 1050 and 1800 - that is, before the Industrial Revolution introduced fossil carbon into the atmosphere.
Using 200,000 data points, the study - believed by Nature to be the most comprehensive of its kind so far - compared the Antarctic ice core record of trapped CO2 bubbles with so-called proxy data like tree rings, which are used to estimate temperature changes.
The most likely value among their estimates suggests that for every degree Celsius of warming, natural ecosystems tend to release an extra 7.7 parts per million of CO2 to the atmosphere (the full range of their estimate was between 1.7 and 21.4 parts per million).
 The oceans' ability to absorb CO2 figures strongly into the debate |
This stands in sharp contrast to the recent estimates of positive feedback models, which suggest a release of 40 parts per million per degree; the team say with 95% certainty that value is an overestimate.
"This is a valuable paper that helps to constrain certain feedback components for the past," said John Schellnhuber, director of the Potsdam Institute for Climate Impact Research.
"However, it is probably not suited for extrapolation into the future and it does not cover the really interesting processes like anthropogenic activation of permafrost carbon or methane clathrates."
The paper will surely not be the last word in this difficult area of research, with multiple uncertainties over data sources.
"I think that the magnitude of the warming amplification given by the carbon cycle is a live issue that will not suddenly be sorted by another paper trying to fit to palaeo-data," Professor Brian Hoskins, a climate expert from Imperial College London, told BBC News.
Another crucial issue is the degree to which past trends will line up with potentially very different future scenarios.
Professor Tim Lenton from the University of East Anglia said: "It looks intriguing and comforting if they are right. The immediate problem I can see is that past variations in CO2 and temperature over the last millennium were very small, and this group are assuming that the relationship they derive from these very small variations can be extrapolated to the much larger variations in temperature we expect this century.
"We have plenty of reason to believe that the shape of the relationship may change (be nonlinear) when we 'hit the system harder'. So, I don't think they can rule out that the positive feedback from the carbon cycle could become stronger in a significantly warmer climate."
| By Michael Fitzpatrick Science reporter, BBC News |
 Frozen depositories are giving up methane to the sea |
Scientists have uncovered what appears to be a further dramatic increase in the leakage of methane gas that is seeping from the Arctic seabed.
Methane is about 20 times more potent than CO2 in trapping solar heat.
The findings come from measurements of carbon fluxes around the north of Russia, led by Igor Semiletov from the University of Alaska at Fairbanks.
"Methane release from the East Siberian Shelf is underway and it looks stronger than it was supposed [to be]," he said.
Professor Semiletov has been studying methane seepage in the region for the last few decades, and leads the International Siberian Shelf Study (ISSS), which has launched multiple expeditions to the Arctic Ocean.
The preliminary findings of ISSS 2009 are now being prepared for publication, he told BBC News.
Methane seepage recorded last summer was already the highest ever measured in the Arctic Ocean.
High seepage
Acting as a giant frozen depository of carbon such as CO2 and methane (often stored as compacted solid gas hydrates), Siberia's shallow shelf areas are increasingly subjected to warming and are now giving up greater amounts of methane to the sea and to the atmosphere than recorded in the past.
| METHANE HYDRATES Methane gas is trapped inside a crystal structure of water-ice The gas is released when the ice melts, normally at 0C At higher pressure, ie under the ocean, hydrates are stable at higher temperatures |
This undersea permafrost was until recently considered to be stable.
But now scientists think the release of such a powerful greenhouse gas may accelerate global warming.
Higher concentrations of atmospheric methane are contributing to global temperature rise; this in turn is projected to cause further permafrost melting and the release of yet more methane in a feedback loop.
A worst-case scenario is one where the feedback passes a tipping point and billions of tonnes of methane are released suddenly, as has occurred at least once in the Earth's past.
Such sudden releases have been linked to rapid increases in global temperatures and could have been a factor in the mass extinction of species.
According to a report by the US National Oceanic and Atmospheric Administration (Noaa), the springtime air temperature across the region in the period 2000-2007 was an average of 4C higher than during 1970-1999.
That is the fastest temperature rise on the planet, claims the university.
The recent thaw over the last decade means that some of the large reserve of carbon from organic material such as dead animals and plants in sediments is now being released into the sea and into our atmosphere.
Trapped below that is the methane hydrate now warming and leaking through holes in the defrosting sediments.
 1. Methane hydrate is stable at high pressure and low temperature 2. Nearer the surface, where water pressure is lower, hydrates break down earlier than at greater depth as temperatures rise 3. Gas rises from the sea-bed in plumes of bubbles - some of it dissolves before it reaches the surface 4. The ISSS team says it has detected methane breaking the ocean surface |
Previously it was thought much of this gas was absorbed into the sea.
But according to a recent report that Professor Semiletov and his team compiled for the environmental group WWF, the shallow depth of arctic shelves means that methane is reaching the atmosphere without reacting to become CO2 dissolved in the ocean.
Professor Semiletov's fellow researcher aboard the Russian icebreaker that carries the ISSS team each year is Professor Orjan Gustafsson from Stockholm University in Sweden.
He said that methane measured in the atmosphere around the region is 100 times higher than normal background levels, and in some cases 1,000 times higher.
'No alarm'
Despite the high readings, Professor Gustafsson said that so far there was no cause for alarm, and stressed that further studies were still necessary to determine the exact cause of the methane seepage.
"It is important now to understand how fast it is being released and how much is being released," he said.
However, there is a real fear that global warming may cause Siberia's subsea permafrost to thaw.
Some estimates put the amount of carbon trapped in shelf permafrost at 1,600 billion tonnes - roughly twice as much carbon as in the atmosphere now.
The release of this once captive carbon from destabilised ocean sediments and permafrost would have catastrophic effect on our climate and life on Earth, warn the scientists.
