Fire Burn and Cauldron Bubble

BBC News reports that methane bubbling up from the Arctic sea floor appears to be stronger than first believed.

Image: National Oceanography Centre, Southampton.

Following a decade of relative stability, the atmospheric concentration of methane began to rise in 2007.

Normally the methane is trapped as methane hydrate, kept stable by low temperatures and high pressure. But as the water in the Arctic warms–temperatures increasing about 1°C in the past 30 years–the depths at which methane hydrate remains stable are starting to decrease. Methane is being released from the East Siberian Shelf.

Prof. Semiletov told the BBC that methane measured in the atmosphere in the region is about 100 times higher than normal background levels, increasing to 1000 times normal in some places. This is a concern to climate scientist since methane is about 20 times more powerful a greenhouse gas than CO2.

“Baring Head station showing that southern hemisphere atmospheric methane increased by 0.7% over the two-year period 2007–08.

There is no current reason for alarm, assures Brooklyn Treehugger Matthew McDermott, but this blog is of the opinion, Why wait? Avoid the rush. Panic now.

Other Recent Treehugger Posts on the Topic of Methane and Global Heating

Arctic ‘warmest in 2,000 years’ (innovationtoronto.com)
Methane release ‘looks stronger’ (news.bbc.co.uk)
Only a Few More Days (jcwinnie.biz)
Where on Earth is it unusually warm? Greenland and the Arctic Ocean, which is marked by rotten ice. (climateprogress.org)
More Methane Discovered Bubbling From Arctic Sea Floor – 1000 Times Background Levels in Places (treehugger.com)

This entry was written by jcwinnie, posted on 2010-1-6 at 6:59 pm, filed under climate, danger, environment, thermodynamics and tagged climate, danger, emissions, thermodynamics. Bookmark the permalink. Follow any comments here with the RSS feed for this post. Both comments and trackbacks are currently closed.

4 Comments

jcwinnie

Posted 2010-3-4 at 5:50 pm | Permalink

National Geographic writer Anne Casselman relays concerns that Arctic seabeds are belching massive quantities of methane. According to a new study, ocean permafrost has begun to melt.

Previous research had found methane bubbling out of melting permafrost—frozen soil—in Arctic wetlands and lakes.

But the permafrost lining the deep, cold seas was thought to be staying frozen solid, holding in untold amounts of trapped methane.

“It’s not the case anymore,” said study leader Natalia Shakhova, a biogeochemist at the University of Fairbanks, Alaska. “The permafrost is actually failing in its ability to preserve this leakage.”

(Related: “Methane Bubbling Up From Undersea Permafrost?”)

In fact, Shakhova and colleagues estimate that roughly eight million tons of methane are leaking into the atmosphere each year from the East Siberia Sea (map), fueling concerns of accelerated global warming.

Methane Feedback Fueling Global Warming?

Shakhova’s team took detailed measurements of methane levels in the water column over the Siberian Arctic shelf during six research cruises from 2003 to 2008.

The 77,204-square-mile (2,000,000-square-kilometer) shelf is characterized by shallow seas less than 164 feet (50 meters) deep, and the permafrost layer extends throughout. (See a detailed map of the Arctic seafloor.)

The scientists found that much of the seawater above the shelf is laden with methane, which in turn is being released into the atmosphere.

What’s more, the team found that current atmospheric methane levels in the Arctic are three times higher than those recorded across previous climate cycles going back 400,000 years.

(Related: “Ancient ‘Snowball Earth’ Melted Fast Due to Methane.”)

This phenomenon most likely isn’t limited to the East Siberian Sea, the researchers note. If permafrost is melting in this part of the Arctic, all shallow areas along the Arctic shelf should be similarly affected.

To help find out, Shakhova and her colleagues plan to drill through the subsea permafrost next spring to establish a regional monitoring network

It’s unclear whether human-induced climate change is causing the leakage. But global warming might be speeding up an otherwise natural part of the climate cycle, Shakhova noted, creating a feedback loop, in which released methane further warms the Earth, melting more permafrost and releasing more methane.

“This [human-made] contribution, or global climate change, might be the last straw, might be the accelerator or trigger,” she said.

The research is published this week in the journal Science.
jcwinnie

Posted 2010-3-4 at 5:59 pm | Permalink

The Gray Lady reassures us that “a scientist who led the study said it was too soon to say whether the findings suggest the potential for a dangerous release of methane.”
jcwinnie

Posted 2010-3-5 at 11:33 am | Permalink

Ever wondered what makes for a Climate Progress nightmare. Wonder no longer.
jcwinnie

Posted 2010-3-8 at 11:25 am | Permalink

After Gutenberg