Wyrd - OE: that which has become; fate-shaping; destiny-unfolding

Monday, 7 November 2011

Frozen box of Pandora stirs in Arctic

Article first published as Bugs ready to munch on climate time-bomb on Technorati.

© Photographer: | Agency: Dreamstime.com
Many strands of our climate's future criss-cross in the far north of the planet. The frozen Arctic is one of the quickest warming parts of our globe, so perhaps that shouldn't come as a surprise. Here you will find fast-shrinking ice-caps; once-fabled sea-ice passages that have newly opened; mysterious methane hydrates, buried in cold sea-muds, which one day could release a stupendous global warming belch.

And frozen bugs.

Surprisingly, it is the frozen bugs in the permanently iced soils – or permafrost – of the Arctic that has scientists worried. Those bugs are sitting within a climate time-bomb; some 1,600 billion tons of carbon that's been locked into the icy soils for millennium. It comes from the dead remains of plants that lived in the far north before the last Ice Age. The bugs were locked in place too, as the ice advanced; and for them, that rich organic matter is food, for when the permafrost soils next melt.

And that melting is already starting in places across the Arctic, with more on the cards. So how those newly defrosted bugs respond, on awakening from their slumber, is critical in deciding what happens to the Arctic's massive permafrost carbon store. Which is why scientists from the Lawrence Berkeley National Laboratory have been looking at the gassy effluence of the permafrost microbial community, in a study just published in Nature.

They have found that, when these bugs spring back to life, they start munching on the dead plant remains straight away – producing methane and CO2 in equal measure. Both are important greenhouse gases, but methane has a stronger short-term boost to warming. But the researchers also noticed that the methane production slowed down within a couple of days. It seems that some bugs find the newly produced methane a tasty alternative foodstuff for themselves, and quickly snap it up.

That could, possibly, be good news. If the same story, of only a short-lived methane burst, pans out for the real-world perma-defrost, then the climate implications could be less severe. Methane is twenty times more potent a greenhouse gas than CO2. But the team also found a worrying sign that another greenhouse gas – nitrous oxide – may be a player too. No microbes seem to put this gas on their menu in the tests conducted. So nitrous oxides could be released in higher quantities than previously thought. And this gas packs a punch 300 times more powerful than CO2.

Whatever the greenhouse gas mix the Arctic's microbes chose to gift us, one thing is clear. The only way to avoid putting Arctic bugs in charge of the planet's thermostat is to prevent the triggering of further melt-off in the far north. And that requires mankind to get a grasp on our own gaseous pollution – with a great deal more haste than has been shown, thus far.

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