Climate Change Releasing Arctic Methane

The Arctic Ocean is being warmed by climate change and low-lying methane is being released as a result.  That’s the potentially worrying verdict of a group of UK scientists who studied an Arctic region off the Norwegian coast, and who have now written about their experiences there. 

What they discovered around the Norwegian Svalbard archipelago area was more than 250 individual gas plumes bubbling from the sea floor up.  These bubbles were comprised in the main of methane, which is a colourless and odourless gas formed of hydrogen and carbon and which - along with carbon dioxide/CO2 - is labelled a greenhouse gas that contributes significantly to the greenhouse effect.   Methane, however, is considered much more potent than CO2.

The likely sources of this Norwegian CO2, scientists Tim Minshull, Graham Westbrook and their colleagues wrote, were methane hydrate reserves located at sub-sea bed level.  These reserves are essentially water ice containing methane, and they are in an area where the temperature has risen by one degree centigrade since the late 1970s. 

“Hydrates are stable only within a particular range of temperatures”, Minshull explained.

“So if the ocean warms, some of the hydrates will break down and release their methane.”

Climate Change Methane

The methane observed by the British scientists did not make it as far as the surface, so is not directly accelerating the growth of climate change methane present in the atmosphere.  However, just by being in the water, the methane can still be a risk, since it can turn into CO2 which, when dissolved, acts to acidify the oceans.  Another possibility is that methane below the sea floor is making it into the atmosphere in other parts of the world.

Commenting on the findings, the Carnegie Institution for Science’s Ronald Cohen described them as significant.  “What's amazing is that they see such enormous quantities of methane”, he added. 

Arctic Climate Change

The scientists’ Arctic climate change study involved analysing just a 600 km2 expanse, where annual methane emissions are likely to be approximately 27 kilotonnes.  This implies that the Svalbard archipelago’s overall volume of methane being released is around the 20 megatonnes-a-year mark.  If this were taking place across the Arctic as a whole, then the implications for climate change could be marked. 

According to current scientific thought, up to 600 megatonnes of methane enter the atmosphere on an annual basis.

See also:

LA Methane Emissions Double Previous Estimates

Arctic Ice Shrinking AND Thinning, says NASA