Tuesday, May 29, 2012

What If the Permafrost Thaws?

http://bit.ly/L0DzFo There is more carbon frozen in far North than in all living things & the atmosphere. It has begun to thaw. Interview with Prof. Antoni Lewkowitcz and Academy of Science speech by Dr. Charles Koven. Radio Ecoshock 120530 1 hour.

Gas pipelines in Siberia are rising out of the ground, while in Alaska oil pipelines sag.

Houses and factories built on permafrost are tipping. Evergreens are slanting in so-called "drunken forests". Under the whole north, land is becoming unstable as the climate warms.

I'm Alex Smith. We're going to find many answers to a simple question: What if the permafrost thaws?

I attended a conference session on that very subject, with expert scientists, at this year's meeting of the American Academy for the Advancement of Science. We'll hear the latest.

But it was rough going. After the session, which was technical and carefully hedged with scientific doubts, I ran into the soil expert for the European Union, Luca Montanarella. I told him, in spite of all I'd heard, I still didn't know whether we should be worried or not.

"You'd like to worry, wouldn't you?" Luca replied, "But we have many more things to worry about now, further south."

Of course Luca is Italian. There were riots in the streets of Italy. The government had fallen, and the banking system might soon follow.

In the course of preparing this program on permafrost, I ran into as many opinions as experts. The permafrost may thaw over hundreds of years. The carbon stored there will come out slowly, one said. Another suggested when that thaw comes, it will already be too late for our civilization, ruined by a changed climate further south.

Other scenarios predict 50 to 80% of permafrost will thaw during this century. Maybe the released greenhouse gases will only equal ten or twenty years of our current emissions, one of our guests says. Only!

Another brand new scientific paper suggests permafrost melt may have caused the great mass extinction 55 million years ago.

We've never seen it. The frost was supposed to be permanent, and has been during human time on Earth. Now the signs of big changes are all around in the Arctic. What is coming? We can only model the future, with very imperfect tools, and guess the rest.

Before we dive into expert level testimony about the latest science, let's start with a more user-friendly Radio Ecoshock interview.

See my detailed notes below on my interview with Antoni Lewkowicz from the University of Ottawa. He's one of the world's recognized experts on permafrost, and yet quite good at explaining these issues to the public.

See my detailed notes from the Lewkowicz interview below. Our theme music this week is from Laurie Anderson's latest album.

The big question for this program, and for the world, is "What if the Permafrost thaws?"

I was unable to find a figure for the amount of the world soil and rock that is frozen. The BBC clip we ran earlier claimed 60% of Russia is permanently frozen ground. There is some permafrost in the Andes of Chile, but most is obviously in Russia, Canada, and Alaska. The United States Permafrost Association estimates about 25% of Earth's surface is frozen, and permafrost may account for up to 40% of all soils on the planet.

As you hear from Dr. Lewkowicz, interest in these frozen northern soils and rocks dropped - until scientists began to calculate a carbon budget for the world. The Wikipedia entry, which is still under construction, says this:

"The most recent work investigating the permafrost carbon pool size estimates that 1400–1700 Gt of carbon is stored in permafrost soils worldwide. This large carbon pool represents more carbon than currently exists in all living things and twice as much carbon as exists in the atmosphere."

Maybe so, but as we'll learn from our next expert, not all of that will reach the atmosphere. And we don't know how long it could take to get there.

CHARLES KOVEN: WHAT DO CLIMATE MODELS PREDICT?

Dr. Charles Koven is a permafrost and soils expert in the climate sciences department of the Berkeley National Lab in California. Along with the renowned Canadian northern soils expert Charles Tarnocai, Dr. Koven was asked to present at the February meeting of the National Academy for the advancement of Science session called "What If The Permafrost Thaws?"

I recorded that session in Vancouver. You can order the whole recording as an mp3 from aven.com as item number AS219.

I'm going to play you some select audio from the Charles Koven talk. It isn't easy, for you and me. First of all, Koven was speaking to experts, not the public. Second, to be frank, neither Koven nor Tarnocai are good public speakers. I think it's too much to ask of our best scientists that they also be master speakers. They spend years in a forbidding field, literally in the cold, and more years working through tedious data in the lab. Their many scientific papers are their voices.

So I've selected the best, and edited out some of the repetitions and pauses, for better radio listening.

Before we begin, you'll also need to understand a few phrases and tools used when trying to answer these difficult problems of permafrost. Dr. Lewkowitcz gave us a leg up. We found out there is no sharp dividing line on a map where permafrost ends, but fingers and islands jutting out from a completely frozen polar area. There is now a free book "The Soil Atlas of the Circumpolar Region" available from the European Union.

There are three different major types of soil, and that matters, since each releases more or less carbon when exposed to decay. As a group these are called Cryosols, in the World Reference Base for Soil Resources, or sometimes Gelisols in official soil lingo.

Complicating it all: the permafrost can be shallow, or very, very deep. You might think that once ancient plant material is buried many feet or meters below the ground, below the reach of living roots, it would stay there. But as anybody in cold winters knows, the soil is always heaving. In the Arctic, with summer surface melt and extreme winter cold, soil layers are tossed about in a process called "cryoturbation". You'll hear about that in the Charles Koven talk.

In the program, I play you a quick clip from Steven Chu, currently the Secretary of Energy for the United States, in the Obama administration. Dr. Chu explains that once the permafrost reaches a certain pace of thawing, it will continue to feed more warming and melting, no matter what humans do. Obviously he takes thawing permafrost seriously, as should we all.

Finally, since we won't know the climate impacts of permafrost melt until it's much too late, the best we can do is make models from huge masses of scientifically collected data. Talk of complex climate models can turn off a lot of radios, I know. I'm only including a short bit on that, from Dr. Koven, because I think you need to get a feel for what we know and don't know. And how good the guesses are so far.

There are at least a dozen serious teams of climate modellers, some running football field sized buildings stuffed full of super computers. Everything from weather records, ocean temperatures, chemical formulae, ice formations, soil types, and even areas of permafrost are fed into these computers, trying to forecast what happens if we burn all the oil, coal and gas, or just some of it.

The results, as you know from the periodic reports of the Intergovernmental Panel on Climate Change, are divided into possible scenarios, with varying levels of confidence. Dr. Koven quickly references the latest models used for the upcoming IPCC assessment - called CEMa, short for Climate Envelop Matching. He also talks about the RCP Level 5 scenario, which is a "moderate" projection of 500 parts per million of carbon dioxide equivalent in the atmosphere by the year 2100. And the RPC 8.5 scenario, which would take us beyond 4 degrees of warming by 2100 - the pedal to the metal scenario of human greenhouse gas emissions.

Hang in there through that modeling talk, and you will be rewarded by some courageous assessments of what really happens if the northern lands thaw. Plus a surprising and controversial suggestion that Arctic methane may not be the boogeyman some suggest.

Good luck to us all. Here are selections from Charles Koven speaking at the American Academy for the Advancement of Science meeting, on February 19th, 2012.

NOTES FROM THE INTERVIEW WITH ANTONI LEWKOWICZ

When we think of planet Earth, we don't picture a frozen planet. But a huge area underground is always icy. We call it the permafrost. You won't find it in your backyard, unless you live in the far north.

Geologists and other scientists have only begun the task of cataloging this underground world. Now, as Earth warms, we all need to know. Because if all the carbon locked up in the north is released, our climate, and our civilization will change beyond recognition.

Professor Antoni Lewkowicz is a central figure unraveling this mystery. From the Department of Geography at Canada's University of Ottawa, Lewkowicz studies, leads doctoral researchers, and advises international groups on permafrost. He's a co-author on a new paper on the impacts of climate change on permafrost in Canada.

Why care about the permafrost? 3 reasons

1. it's a good thermometer. Unlike measuring air temperatures, which is tricky, measuring deeper in the ground is more solidly known. We know the melting is real, permafrost doesn't lie, proves global warming is happening.

2. Large emissions of carbon could result from melting, but we don't yet know how much. It will affect people all over the world. We know there are massive stocks of carbon locked up there - but how long will it take to be released?

3. It costs money. Governments, corporations, and individuals have to spend money to protect infrastructure or deal with changes in the ground, from "drunken forests" to sagging pipelines, to tipping buildings and sinking roads.

For example within 100 miles of the border between the Canadian Yukon and Alaska, the Alaska Highway is full of dips and rises from melting permafrost. That highway is a huge investment by both countries and continuing costs will be high. It already costs tens of millions to maintain the Alaska Highway.

Coastal erosion, as frozen ground gives way, is also a huge problem. Most of the Northern settlements are on the coast. The First Nations aboriginal people were dependent on fishing and hunting sea mammals - now their settlements are either tipping over, or in some cases, falling into the sea with coastal erosion.

Longer ice-free season can lead to bigger waves and more storms. Erosion can be tens of meters per year in some cases.

The depth of permafrost is quite variable. At the far northern tip of Canada at Ellesmere Island the permafrost is several hundred meters thick, probably five to seven hundred meters thick. Its temperature is about minus fifteen.

As you go south, it gets thinner. In the far north, the permafrost is continuous, under everything. Further south, some places have permafrost, others not. It becomes dispersed and localized.

Again, in some areas the organic material, which could be released as either carbon dioxide or methane, has been accumulating for thousands of years. In other areas it may be just hundreds of years. It’s like a jig-saw puzzle with many different pieces.

Parts of Alaska were not glaciated in the last great ice age, and continued growing plant life. Those accumulated much more organic material. This was gradually incorporated in the frozen ground, to be stored without decay.

Lewkowicz is a lead author of a new paper published in the Canadian Journal of Earth Sciences. The title is "Climate and Ground Temperature Relations, Sites Across the Continuous and Discontinuous Zones in Northern Canada, with co-authors Jennifer Troop and Sharon Smith, from the Geological Survey of Canada. As part of the International Polar Year, which ended in 2009, they developed a new series of bore hole temperature readings.

As you would suspect, the climate does determine ground temperatures. While some of the far North is still very cold under the surface, a little further South is just below zero, on its way to melting. These scientists were able to form a continent-wide reading of the permafrost.

I raised the fascinating videos showing up on You tube of thousands of new small lakes appearing in Siberia as the permafrost thaws there.

Although there is very strong warming in Canada, particularly in the Mackenzie Valley, Professor Lewkowitcz doesn't think Canada is experiencing the rather sudden appearance of so many lakes as in Siberia. In the Western Canadian Arctic average annual temperatures have risen by as much as a degree Celsius in a decade.

Some Canadian peat lands are decaying relatively rapidly and you can see that through satellite photos.

In one area of discontinuous permafrost areas in the Southern Yukon and Northern British Columbia, half the sites measured have thawed since 1964.

But if we go to the extreme North, like Alter Bay, the ground may be a degree warmer, but it has only moved from about 14 degrees below zero C. to perhaps 13 degrees. It is relatively warmer, but now where close to thawing yet.

Scientists prefer to use the word "thaw" rather than "melt". Lewkowicz gives the example of a frozen turkey. If you thaw a turkey, you still have it to eat. If you melt something, it's gone. Permafrost isn't just ice. It can be only frozen rock for example. That may thaw without melting. Technically, "permafrost" is defined by sub-zero temperature for two or more years, no matter what is frozen under the surface. Professor Lewkowicz just attended a post Polar Year conference in Montreal. The hot topic was: how much carbon will be released as the permafrost melts? There is a lot of new research into this question, partly because we don't yet have firm answers. We don't know.

We do know that where the organic material decays without water, it will release carbon dioxide. If the decay happens in water, methane is released instead. So there are many further calculations about how much comes out of lakes, bogs, and swamps - versus how much material will thaw and rot in simple exposed ground.

The second big question is: how fast will it happen?

Again this is complex, and one factor is water. If ponds form, as they do in Siberia, that water efficiently transfers the heat from the Sun and warmer air down into the ground. More greenhouse gases will be released there. This can become a positive feedback effect, where smaller ponds warm to form larger ponds, and so more warming.

Regarding the coming greenhouse gas emissions from thawing permafrost, Lewkowicz says "We don't have the answer yet, but we know it's a really, really serious question."

There is a potential for a positive feedback effect, where thawing permafrost releases warming gases which melts more permafrost, increasing that cycle at a faster rate.

Like the melting Arctic Sea Ice, "it's difficult to imagine how we can revert to a previous condition" [of permafrost]. "It's quite difficult to thaw ground, but it's actually quite difficult to freeze ground... once we thaw it, I don't know how we are going to freeze it again."

I think this is a key point about thawing permafrost. There isn't any realistic geo-engineering scheme to reverse it. The area of permafrost is so huge, and the amount of energy require to freeze it so gigantic, this process is beyond human control, once we initiate the warming and thawing process. It is an irreversible change to the planet.

Lewkowicz says there will still be permafrost left in all our lifetimes. The question is how much, and what will the impacts of the thawing be?

Listen again to this show, or pass it around as a free mp3, from our program archives at ecoshock.org.

Should we worry about the permafrost thaw? Maybe not today or tomorrow. The big thaw is happening slowly. It will define the history of the planet. As the Russian expert Sergei Kirpotin of Tomsk University says: the process is already underway. We can delay it, with smarter energy choices, and greenhouse gas control, but unless a miracle happens, over the next century or three, planet Earth will thaw.

I'm Alex Smith for Radio Ecoshock. I appreciate your patience and your brain power. Thank you for caring about your world.

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