Leaking Siberian ice raises a tricky climate issue

[Joanne98]

CHERSKY, Russia – The Russian scientist shuffles across the frozen lake, scuffing aside ankle-deep snow until he finds a cluster of bubbles trapped under the ice. With a cigarette lighter in one hand and a knife in the other, he lances the ice like a blister. Methane whooshes out and bursts into a thin blue flame.

Gas locked inside Siberia's frozen soil and under its lakes has been seeping out since the end of the last ice age 10,000 years ago. But in the past few decades, as the Earth has warmed, the icy ground has begun thawing more rapidly, accelerating the release of methane — a greenhouse gas 23 times more powerful than carbon dioxide — at a perilous rate.

Some scientists believe the thawing of permafrost could become the epicenter of climate change. They say 1.5 trillion tons of carbon, locked inside icebound earth since the age of mammoths, is a climate time bomb waiting to explode if released into the atmosphere.

"Here, total carbon storage is like all the rain forests of our planet put together," says the scientist, Sergey Zimov — "here" being the endless sweep of snow and ice stretching toward Siberia's gray horizon, as seen from Zimov's research facility nearly 350 kilometers (220 miles) above the Arctic Circle.

http://news.yahoo.com/s/ap/20101121/ap_on_sc/eu_climate_siberian_meltdown;_ylt=AsF0QusFkKW4zTE21mE1Aaw0vTYC;_ylu=X3oDMTNuanJqM2lqBGFzc2V0Ay9zL2FwLzIwMTAxMTIxL2FwX29uX3NjL2V1X2NsaW1hdGVfc2liZXJpYW5fbWVsdGRvd24EY2NvZGUDcmRuYmUEY3BvcwM4BHBvcwM4BHNlYwN5bl90b3Bfc3RvcmllcwRzbGsDbGVha2luZ3NpYmVy

[bemildred]

1. Well, I think it's already too late (the methane release), but you never know.

Mother Nature is way the heck more complex than we give her credit for.

[Uncle Joe]

2. Honestly, I don't see how this thaw could always be gradual.

The Methane deposits may not thaw quickly as in 40 years instead of 10 but there must be a tipping point and when that's reached, the change will be dramatic, overnight.

More than 50 billion tons could be unleashed from Siberian lakes alone, more than 10 times the amount now in the atmosphere, she said.

But the rate of defrosting is hard to assess with the data at hand.

"If permafrost were to thaw suddenly, in a flash, it would put a tremendous amount of carbon in the atmosphere. We would feel temperatures warming across the globe. And that would be a big deal," she said. But it may not happen so quickly. "Depending on how slow permafrost thaws, its effect on temperature across the globe will be different," she said.

Thanks for the thread, Joanne.

[Igel]

3. Because the permafrost is situated in 3 dimensions.

Thawing also happens in 3 dimensions.

So the thawing may proceed deeply in some areas and not in others, or it may be shallow and widespread. The areas with concentrations of methane may not be where warming occurs, or there may be no methane at the depths mostly affected.

It matters how the methane is distributed not only over the earth's surface but also into the earth's surface; it matters how the warming occurs, and how deeply the warmth lasts (and therefore how deeply the heat penetrates).

It matters what's growing where the permafrost melts. It matters what the wind currents are.

The distribution and rate is important because methane is destroyed both in the biosphere as well as at higher altitudes. The world is complex and finely granular. The models are still relatively simple and coarse.