Huge methane leak in Arctic Ocean: study
Friday 05 March 2010
Methane is leaking into the atmosphere from unstable permafrost in the Arctic Ocean faster than scientists had thought and could worsen global warming, a study said Thursday.
From 2003 to 2008, an international research team led by University of Alaska-Fairbanks scientists Natalia Shakhova and Igor Semiletov surveyed the waters of the East Siberian Arctic Shelf, which covers more than 772,200 square miles (two million square kilometers) of seafloor in the Arctic Ocean.
"This discovery reveals a large but overlooked source of methane gas escaping from permafrost underwater, rather than on land," the study said.
"More widespread emissions could have dramatic effects on global warming in the future."
Earlier studies in Siberia had focused on methane escaping from thawing permafrost on land.
Scientists have long thought that the permafrost under the East Siberian Arctic Shelf acted as an impermeable barrier that sealed in methane, a powerful greenhouse gas 30 times more potent that carbon dioxide.
But the research team's observations showed that the permafrost submerged on the shelf is perforated and leaking large amounts of methane into the atmosphere.
More than 80 percent of the deep water and more than half of surface water had methane levels around eight times higher than found in normal seawater, according to the study published in the journal Science.
The researchers warned that the release of even a fraction of the methane stored in the shelf could trigger abrupt climate warming.
"Ocean-bottom permafrost contains vast amounts of carbon, and experts are concerned that its release as methane gas would lead to warmer atmospheric temperatures, thus creating a positive-feedback loop that would lead to more methane escaping from the permafrost and more global warming," they said.
Current average methane concentrations in the Arctic average about 1.85 parts per million, the highest in 400,000 years, said Shakhova.
Concentrations above the East Siberian Arctic Shelf are even higher, and scientists are concerned because the undersea permafrost "has been showing signs of destabilization already," she added.
"If it further destabilizes, the methane emissions... would be significantly larger."
Geological records indicate that atmospheric methane concentrations have varied between about .3 to .4 parts per million during cold periods to .6 to .7 parts per million during warm periods.
As Iraq runs dry, a plague of snakes is unleashed
The top 10 weirdest animal mating rituals
Cornwall hotter than California? British sea temperatures hit all-time high
The ten best cycling accessories
The ugliest animals on earth: Blobfish, axolotl and proboscis monkey battle it out to be named least attractive beast
- 1 Woman and two children killed by mob in riots over 'blasphemous' Facebook post in Pakistan
- 2 Christians: The world's most persecuted people
- 3 The secret report that helps Israel hide facts
- 4 Danish TV reporter is all business up top, all party down below
- 5 Ross Burden dead: MasterChef and Ready Steady Cook star dies at age 45
The secret report that helps Israel hide facts
A day in the life of Vladimir Putin: The dictator in his labyrinth
Were 'Poor Doors' added to mixed developments so wealthy residents don't have to go in alongside social housing tenants?
A new Russian revolution: The cracks are starting to appear in Putin’s Kremlin power bloc
Arizona execution lasts two hours as killer Joseph Wood left 'snorting and gasping' for air
Opponents of Israel's military operation in Gaza are the real enemies of Middle Eastern peace
Excellent Salary : Austen Lloyd: BRISTOL - NICHE DEFENDANT FIRM - Defendant Pe...
£45000 - £60000 per annum + competitive: Progressive Recruitment: JAVA DEVELO...
£30000 - £34000 Per Annum 25 days holiday, Private healthcare: Clearwater Peop...
£475 - £550 per day: Progressive Recruitment: MDAX / Dynamics AX / Microsoft D...