Danger from the deep: New climate threat as methane rises from cracks in Arctic ice

Scientists shocked to find greenhouse gas 70 times more potent than CO2 bubbling from deep ocean

A new source of methane – a greenhouse gas many times more powerful than carbon dioxide – has been identified by scientists flying over areas in the Arctic where the sea ice has melted.

Click here to see 'The deadly depths - Methane release in the Arctic' graphic

The researchers found significant amounts of methane being released from the ocean into the atmosphere through cracks in the melting sea ice. They said the quantities could be large enough to affect the global climate. Previous observations have pointed to large methane plumes being released from the seabed in the relatively shallow sea off the northern coast of Siberia but the latest findings were made far away from land in the deep, open ocean where the surface is usually capped by ice.

Eric Kort of Nasa's Jet Propulsion Laboratory in Pasadena, California, said that he and his colleagues were surprised to see methane levels rise so dramatically each time their research aircraft flew over cracks in the sea ice.

"When we flew over completely solid sea ice, we didn't see anything in terms of methane. But when we flew over areas were the sea ice had melted, or where there were cracks in the ice, we saw the methane levels increase," Dr Kort said. "We were surprised to see these enhanced methane levels at these high latitudes. Our observations really point to the ocean surface as the source, which was not what we had expected," he said.

"Other scientists had seen high concentrations of methane in the sea surface but nobody had expected to see it being released into the atmosphere in this way," he added.

Methane is about 70 times more potent as a greenhouse gas than carbon dioxide when it comes to trapping heat. However, because methane is broken down more quickly in the atmosphere, scientists calculate that it is 20 times more powerful over a 100-year cycle. The latest methane measurements were made from the American HIPPO research programme where a research aircraft loaded with scientific instruments flies for long distances at varying altitudes, measuring and recording gas levels at different heights.

The study, published in the journal Nature Geoscience, covered several flights into the Arctic at different times of the year. They covered an area about 950 miles north of the coast of Alaska and about 350 miles south of the North Pole. Dr Kort said that the levels of methane coming off this region were about the same as the quantities measured by other scientists monitoring methane levels above the shallow sea of the East Siberian Arctic Shelf.

"We suggest that the surface waters of the Arctic Ocean represent a potentially important source of methane, which could prove sensitive to changes in sea ice cover," the researchers write. "The association with sea ice makes this methane source likely to be sensitive to changing Arctic ice cover and dynamics, providing an unrecognised feedback process in the global atmosphere-climate system," they say.

Climate scientists are concerned that rising temperatures in the Arctic could trigger climate-feedbacks, where melting ice results in the release of methane which in turn results in a further increase in temperatures.

"We should be concerned because there's so many things in the Arctic where the warming feeds further warming. There are many things in the Arctic that do respond to warming," said Euan Nisbet, a methane expert at Royal Holloway University of London.

Start your day with The Independent, sign up for daily news emails
Arts and Entertainment
Attenborough with the primates
tvWhy BBC producers didn't want to broadcast Sir David Attenborough's famed Rwandan encounter
News
Campbell: ‘Sometimes you have to be economical with the truth’
newsFormer spin doctor says MPs should study tactics of leading sports figures like José Mourinho
Sport
football
Life and Style
Agretti is often compared to its relative, samphire, though is closer in taste to spinach
food + drink
News
Kelly Osbourne will play a flight attendant in Sharknado 2
people
News
Down-to-earth: Winstone isn't one for considering his 'legacy'
people
News
The dress can be seen in different colours
i100
Sport
Wes Brown is sent-off
football
Voices
Lance Corporal Joshua Leakey VC
voicesBeware of imitations, but the words of the soldier awarded the Victoria Cross were the real thing, says DJ Taylor
Life and Style
Alexander McQueen's AW 2009/10 collection during Paris Fashion Week
fashionMeet the collaborators who helped create the late designer’s notorious spectacles
ebooks
ebooksA special investigation by Andy McSmith
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Bookkeeper / Office Co-ordinator

£9 per hour: Recruitment Genius: This role is based within a small family run ...

Recruitment Genius: Designer - Print & Digital

£28000 - £32000 per annum: Recruitment Genius: This Design and marketing agenc...

Recruitment Genius: Quantity Surveyor

£46000 per annum: Recruitment Genius: This property investment firm are lookin...

Recruitment Genius: Telesales / Telemarketing Executive - OTE £30k / £35k plus

£18000 - £35000 per annum: Recruitment Genius: This company specialises provid...

Day In a Page

War with Isis: Fears that the looming battle for Mosul will unleash 'a million refugees'

The battle for Mosul will unleash 'a million refugees'

Aid agencies prepare for vast exodus following planned Iraqi offensive against the Isis-held city, reports Patrick Cockburn
Yvette Cooper: We can't lose the election. There's too much on the line

Yvette Cooper: We can't lose the election. There's too much on the line

The shadow Home Secretary on fighting radical Islam, protecting children, and why anyone in Labour who's thinking beyond May must 'sort themselves out'
A bad week for the Greens: Leader Natalie Bennett's 'car crash' radio interview is followed by Brighton council's failure to set a budget due to infighting

It's not easy being Green

After a bad week in which its leader had a public meltdown and its only city council couldn't agree on a budget vote, what next for the alternative party? It's over to Caroline Lucas to find out
Gorillas nearly missed: BBC producers didn't want to broadcast Sir David Attenborough's famed Rwandan encounter

Gorillas nearly missed

BBC producers didn't want to broadcast Sir David Attenborough's famed Rwandan encounter
Downton Abbey effect sees impoverished Italian nobles inspired to open their doors to paying guests for up to €650 a night

The Downton Abbey effect

Impoverished Italian nobles are opening their doors to paying guests, inspired by the TV drama
China's wild panda numbers have increased by 17% since 2003, new census reveals

China's wild panda numbers on the up

New census reveals 17% since 2003
Barbara Woodward: Britain's first female ambassador to China intends to forge strong links with the growing economic superpower

Our woman in Beijing builds a new relationship

Britain's first female ambassador to China intends to forge strong links with growing economic power
Courage is rare. True humility is even rarer. But the only British soldier to be awarded the Victoria Cross in Afghanistan has both

Courage is rare. True humility is even rarer

Beware of imitations, but the words of the soldier awarded the Victoria Cross were the real thing, says DJ Taylor
Alexander McQueen: The catwalk was a stage for the designer's astonishing and troubling vision

Alexander McQueen's astonishing vision

Ahead of a major retrospective, Alexander Fury talks to the collaborators who helped create the late designer's notorious spectacle
New BBC series savours half a century of food in Britain, from Vesta curries to nouvelle cuisine

Dinner through the decades

A new BBC series challenged Brandon Robshaw and his family to eat their way from the 1950s to the 1990s
Philippa Perry interview: The psychotherapist on McDonald's, fancy specs and meeting Grayson Perry on an evening course

Philippa Perry interview

The psychotherapist on McDonald's, fancy specs and meeting Grayson Perry on an evening course
Bill Granger recipes: Our chef recreates the exoticism of the Indonesian stir-fry

Bill Granger's Indonesian stir-fry recipes

Our chef was inspired by the south-east Asian cuisine he encountered as a teenager
Chelsea vs Tottenham: Harry Kane was at Wembley to see Spurs beat the Blues and win the Capital One Cup - now he's their great hope

Harry Kane interview

The striker was at Wembley to see Spurs beat the Blues and win the Capital One Cup - now he's their great hope
The Last Word: For the good of the game: why on earth don’t we leave Fifa?

Michael Calvin's Last Word

For the good of the game: why on earth don’t we leave Fifa?
HIV pill: Scientists hail discovery of 'game-changer' that cuts the risk of infection among gay men by 86%

Scientists hail daily pill that protects against HIV infection

Breakthrough in battle against global scourge – but will the NHS pay for it?