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Author Topic: Why is permafrost melting if the world is only 0.6 deg warmer than normal?  (Read 6173 times)

Johann Mahne

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 I've seen a graph that shows that temperatures have increased by 0.2 deg C per decade since 1880.
Why then is the permafrost melting in Alaska, and why is the Alsakan average temperature so much warmer than the world?


 

Offline CliffordK

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Permafrost is essentially the point where the average temperature for the entire year is 0°C/32°F, or less.

A change of ½°C shouldn't be considered as a melting of the permafrost, but rather a migration of the boundary of the permafrost region northward by a certain distance, perhaps 100 miles or so.

Keep in mind that the temperatures in Antarctica and Argentina seem to be changing less than those in the Northern Hemisphere.  See the chart I just threw together.



I think there are a couple of issues with the warm weather in the North.

First of all, there are some long cycles of weather patterns.  The North Atlantic goes through a pattern called Atlantic Multidecadal Oscillation (AMO) with warm and cold cycles lasting about 30 years each, or about 60 years for a complete cycle.  We are currently in a warm phase of the AMO.

There may be other similar oscillations for other aspects of the climate including a PDO (Pacific Decadal Oscillation).

With the global warming theory, one must also consider the effect of humidity, water vapor, and clouds, and perhaps the combined effect of humidity and Carbon Dioxide.

The water vapor carrying capacity is much lower in the colder air of the polar regions than in the tropical regions.  This means that less outgoing IR radiation is blocked by the moisture in the air, and thus proportionally more IR would be blocked by the CO2.

This, however, doesn't adequately account for the differences between the North Polar region and South Polar region. 
 

Johann Mahne

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Thank you CliffordK,a very good explanation.
 

Offline CliffordK

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Good to see somebody read my notes.

Also, with permafrost, keep in mind that it is all about average temperatures (in the ground).  In many places, the upper layers will melt every year, and allow the growth of Arctic Tundra.  The lower layers remain frozen.  Much deeper, of course, the crust starts warming again.

There is a term called "drunken forest" as some permafrost melts, and allows the ground to destabilize.

http://en.wikipedia.org/wiki/Drunken_trees
http://feww.wordpress.com/2008/06/11/drunken-forest/

The photos I have seen show apparently young trees.  I don't know if this is a periodic event.
 

Offline yor_on

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Ah well Mahne?

You don't believe it, do you?

"But why should we care about one degree of warming? After all, the temperature fluctuates by many degrees every day where we live.

The global temperature record represents an average over the entire surface of the planet. The temperatures we experience locally and in short periods can fluctuate significantly due to predictable cyclical events (night and day, summer and winter) and hard-to-predict wind and precipitation patterns. But the global temperature mainly depends on how much energy the planet receives from the Sun and how much it radiates back into space—quantities that change very little. The amount of energy radiated by the Earth depends significantly on the chemical composition of the atmosphere, particularly the amount of heat-trapping greenhouse gases.

A one-degree global change is significant because it takes a vast amount of heat to warm all the oceans, atmosphere, and land by that much. In the past, a one- to two-degree drop was all it took to plunge the Earth into the Little Ice Age. A five-degree drop was enough to bury a large part of North America under a towering mass of ice 20,000 years ago."

As another reference for its importance, for each deg F. of ocean warming there is a 4% increase in water vapor, with a 6-8% increase in rainfall, according to Dr. Kevin Trenberth, head of the Climate Analysis Section at the National Center for Atmospheric Research.

NASA, with references.

As for the Arctic. Climate Change in Arctic More Extensive Than Expected. Discussing permafrost taken from Lunds university Sweden.

It's not getting better, and its not to be ignored, or expected to be a 'variable' as far as I can see. The IPCC report have all been wrong so far and underestimated the speed with which the ice retreats. The Arctic ice sheet is roughly equally spread out this year, but much thinner.

What's really sad is that we seem to put the satellite monitoring on a shelf, at the same time as the warming accelerate. "There was also concern about the adequacy of the agency’s earth science programs. Bolden described problems confronting some earth satellite replacement programs, and starkly warned the committee “we are in dire straits as a nation when it comes to weather and climate prediction.”  He was blunt in calling, as “dumb things” congressional attempts to defund a satellite program that would measure, among other data, shifting changes in the world’s climate.  “I don’t do global warming, I do earth science,” he said emphatically." 

2012 NASA Budget Request. 

Still, it (the report) probably describes us humans quite well.
We're best on arguing, and gaining profits.
« Last Edit: 03/09/2011 12:30:46 by yor_on »
 

Offline CZARCAR

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Isnt the earth closer to the sun when the S hemisphere is summer & farther in winter? How might this factor in?
 

johan_M

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WASHINGTON (AP) — Massive amounts of greenhouse gases trapped below thawing permafrost will likely seep into the air over the next several decades, accelerating and amplifying global warming, scientists warn.

Those heat-trapping gases under the frozen Arctic ground may be a bigger factor in global warming than the cutting down of forests, and a scenario that climate scientists hadn't quite accounted for, according to a group of permafrost experts. The gases won't contribute as much as pollution from power plants, cars, trucks and planes, though.

The permafrost scientists predict that over the next three decades a total of about 45 billion metric tons of carbon from methane and carbon dioxide will seep into the atmosphere when permafrost thaws during summers. That's about the same amount of heat-trapping gas the world spews during five years of burning coal, gas and other fossil fuels
 

Offline yor_on

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To start.

"In a mere 200 years man has increased the CO2 in the atmosphere by 100 ppm (parts per million). This corresponds to the increase during the transition from a glacial to an interglacial period, which under natural conditions, however, would have taken several thousand years.

Today, CO2 in the atmosphere is the highest it has been in the past several million years, and the emission in recent years was also higher than assumed by the IPCC report in its worst case scenarios."

Then why and how the polar regions can be so much faster warming up.

"The polar regions are important regulators and drivers of the World's climate. The large depressions, which affect the global weather patterns, originate there. Figuratively speaking, the polar regions are the weather kitchens of the Earth's climate. Much of the weather that affects us in Europe comes from the Arctic. Our models show that in the future, polar regions will warm up much faster than the rest of the world. They are, literally, "hot spots" of future climate evolution."

"The Antarctic Peninsula, particularly the West coast of the Peninsula is warming at a rate about 10 times faster than the global average. This has received a great deal of publicity in recent years and of course is where the Larsen B ice shelf (see above) is situated. The average annual temperature of this region has increased by nearly 3°C in the last 50 years.

However, data on temperatures in Antarctica only really go back about 50 years, anything beyond that is surmised from ice cores or other sources and so we don't really know how the temperatures vary over even the medium term in Antarctica. The Antarctic Peninsula also represents only about 4% of the whole continent, the other 96% appears to have had a stable temperature over the last 40 years to the extent where the most remarkable aspect is the stability compared to other parts of the world. . This is no reason to become complacent however as part of the reason that the Antarctic ice sheet is so cold is that it's so high, due to the thickness of the ice. The melting and flow of the glaciers removing ice from the continent is also slowed by the ice shelves around the continent edge.

Small rises in temperature that start to nibble away a little faster at the edges could eventually speed up the loss of ice and cause greater temperature rises to take place further inland. Ice shelves seem to act as "corks" in the Antarctic "ice-bottle", remove the ice shelf and a huge amount of ice from the interior could start to flow towards the sea where it will melt even though the temperature in the interior may be stable. The "corks" are currently keeping the ice at the coldest places."

 
And that's West Antarctica that Hansen worried about in the 90:s as it leans downward and will allow ice fields/glaciers to 'glide' out to the ocean where it will break up and start to drift.

In Antarctica "krill numbers may have dropped by as much as 80% since the 1970's - so today's stocks are a mere 1/5th of what they were only 30 years ago. The decline in krill may  in turn account for the decline in the numbers of some penguin species. Dr Angus Atkinson from British Antarctic Survey, says: "This is the first time that we have understood the full scale of this decline. Krill feed on the algae found under the surface of the sea-ice, which acts as a kind of 'nursery'.

    The Antarctic Peninsula, a key breeding ground for the krill, is one of the places in the world where there has been the greatest rise in temperatures due to global warming. This region has warmed by 2.5°C in the last 50 years (much more than the mean global rate), with a striking consequential decrease in winter sea-ice cover. "We don't fully understand how the loss of sea-ice here is connected to the warming, but we believe that it could be behind the decline in krill.""

When it comes to the Arctic the "Arctic air is warming twice as fast as the atmosphere as a whole. Some of the causes of this are understood, but some are not. The darkness of land and water compared with the reflectiveness of snow and ice means that when the latter melt to reveal the former, the area exposed absorbs more heat from the sun and reflects less of it back into space. The result is a feedback loop that accelerates local warming. Such feedback, though, does not completely explain what is happening. Hence the search for other things that might assist the ice’s rapid disappearance.

One is physical change in the ice itself. Formerly a solid mass that melted and refroze at its edges, it is now thinner, more fractured, and so more liable to melt. But that is (literally and figuratively) a marginal effect. Filling the gap between model and reality may need something besides this. The latest candidates are “short-term climate forcings”. These are pollutants, particularly ozone and soot, that do not hang around in the atmosphere as carbon dioxide does, but have to be renewed continually if they are to have a lasting effect. If they are so renewed, though, their impact may be as big as CO2’s.

At the moment, most eyes are on soot (or “black carbon”, as jargon-loving researchers refer to it). In the Arctic, soot is a double whammy. First, when released into the air as a result of incomplete combustion (from sources as varied as badly serviced diesel engines and forest fires), soot particles absorb sunlight, and so warm up the atmosphere. Then, when snow or rain wash them onto an ice floe, they darken its surface and thus cause it to melt faster."

When it comes to Permafrost.

"Permafrost, is soil with a temperature at or below the freezing point of water for two or more years, and is thus permanently frozen. The permafrost regions of the Earth are surprisingly large. They make up at least 25 percent of the earth's surface, which means that they underlie approximately one quarter of the land surface on our planet. Large regions, particularly in Siberia, but also in Canada and Alaska are characterized by these frozen landscapes. In Central Siberia the soil can be frozen to a depth of over 1500 meters.

More than 600 boreholes in various permafrost areas have been equipped with thermometers. We are observing warming of the soil to a depth of some 40 meters in many regions of Alaska, Canada and Siberia. This is happening especially where the permafrost is already relatively warm- about minus one to minus two degrees. There permafrost begins to thaw in the summer and in some areas no longer freezes in winter. Massive changes in the landscape occur. Where the permafrost is rich in ice, it turns boggy and formerly dry areas change to swamp or marshland. In some regions trees begin to tilt or fall, because they lose their hold in the ground."

"There are some dramatic changes. Particularly in Siberia, where some railway can no longer used, because rails have subsided. At an airport in Siberia, I saw that the runway in some places could not be used, because it had collapsed due to the thawing permafrost. In Russia, Alaska and Canada, oil pipelines have become unstable. This could lead to rupturing and the spilling of hundreds of thousands of litres of oil. In addition, the coasts are becoming eroded, and houses are falling into the sea. Thus there are many dangers that we have previously been unaware of."

Add to that methane pipelines drawn on such ground, already and normally expected to lose about 30% of the methane, due to 'natural causes' meaning that their construction is such that you have to accept it, world wide. That means everywhere those pipes are drawn. Not a unique Russian problem and not only in cold climates.

"We know that the methane comes from three different sources. First: In the summer bacteria produce methane on the melted surfaces. An increasing paludification of the landscape could speed up methane production. Second: Free methane and carbon are sequestered at depths of up to of 30 meters in the frozen soil. When the permafrost thaws, the methane could escape, and carbon could be converted to greenhouse gases by bacteria. Thirdly: There could be tremendous amounts of gas hydrates at greater depths, i.e. methane trapped in frozen water. So far, this methane has not escaped because the permafrost constitutes a mighty lid on this source. However, should the permafrost begin to thaw in the shallow marine areas, this frost cover could become porous - veritable chimneys, through which the methane can escape. We do not yet know how big this threat is. This requires further research."
 
Add to that that methane also will covert partly into CO2 as a end product, its 'CO2 tail', staying in the atmosphere for thousand of years. And that there are a lot of natural CO2 (carbon) frozen as well in the Permafrost, decaying and realising gas as the climate gets warmer.

All of this will have a effect on under-water currents, as Europe's Gulf stream for example, also on the atmosphere and its circulation around the globe, and on the marine life, as krill and plankton are the first steps in our marine food chain. As for what that will create in the coastal zones of diverse countries is impossible to predict, but it won't be as you are used too. The same can be said for storms that will became stronger as the warming continues, the worlds ocean-waves are already moving faster due to the extra heat stored inside them. You will also find more humidity in the air, which should fall out as rain in summer, possibly also as more snow in the winter, all depending on the local weather patterns.

Add to that ocean acidification, that may kill off many species of fish we eat.

"According to some predictions, we could see a shift of 0.45 pH units by 2100 and even 0.77 pH units by 2300. The latter would correspond to a 6-fold increase in acidity, meaning that we would find oceans quite different from today, in which the equilibrium will have shifted dramatically to a higher proportion of less sensitive organisms. In some regions sensitive species such as corals might even go extinct. The polar oceans would be most severely affected. Recent research indicates that certain bivalve species (clams) have a reduced capacity to compensate for a change in their acid-base status. However, the tropics, with its coral reefs could also be strongly affected, owing to a combination of warming and acidification, which would be especially aggravating.  . In recent years we have observed that fish stocks are changing their range of distribution. One prominent example is the cod, which is leaving the southern North Sea zone and shifting its range to the north. However, we do not yet know, to what extent the temperature tolerance of cod is affected by acidification. Mussel aquaculture could also be affected. We already see today that large mussel cultures in the northern Mediterranean are affected by the warming trend in the summer months. It is quite apparent that these animals have already reached their thermal limits and would additionally be stressed by future ocean acidification. "

Antarctica Global Warming.

What role do the polar regions play in the Earth's climate.  Do take a walk inside this site, it has a lot of good information.

Global Warming and the Arctic FAQs, also have some info particular to USA Canada.

The Ecconomist 2011. Arctic sea ice is melting far faster than climate models predict. Why?
« Last Edit: 04/12/2011 21:33:26 by yor_on »
 

Offline yor_on

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Btw: If anyone is stupid enough to see it as a boon that the Arctic and Antarctic is melting. China is already working its way into the Arctic Council, the club of Arctic nations that have a decisive role in exploiting what new energy resources  we find there. They have no regional bindings to any of those regions, but they will make a stand. And so I can guarantee that India Japan etc, including most of the developing countries will too.

I expect there to be no Country today, that will allow itself to pay the price in human lives, allowing a few other getting their slightly longer lease on 'luxury', and a 'modern' idiotic, use and throw away, western lifestyle. And if they are ignored I predict a lot of new 'terrorists', all over the world. And that will mean economical wars, for resources.

The time of the Banana republics and gunboats may be over.
But war isn't.
 

Offline CliffordK

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There would certainly be benefits of having multiple shipping routes between the Atlantic and the Pacific Oceans, including the Northwest Passage (summer only) Northeast Passage (summer only), Panama, and down around South America.

Russia is certainly investing in transportation through the Northeast passage.
 

Offline yor_on

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Yes, they will. Global Warming is not anything that will stop Russia from reaping the benefits of the Arctic melting, neither will it stop Canada, or USA. And China and India wants to grow, to give their masses those 'western benefits' they expect. China especially, which btw also seem to have become USA:s new bankers, lending USA a lot of yearly money, so that Americans can continue to consume Chinas cheap goods.

So nobody will rock the boat, not even to plug the worst holes. It's a economical deadlock where the newly industrialized countries need cheap energy, and f* global warming. Combined with the threat of economical decline for all countries ready to do something. Also giving the rich countries their excuse for doing nothing, blaming it on the developing countries unwillingness.

There's also talk about leaving climate agreements to those that understand its 'implications', now after the Durban talks became a fiasco. Namely the banks and national financial institutes  :) Which makes me feel all warm and protected. I'm sure they will launch a new financial derivate, magically fixing global warming, with all countries able to grow fiscally 3-4% annually. As demanded by financial wizardry and 'common economic sense'.

What it seems to comes down to is what one think is worst, global warming, or a economic slump? And so far the economic slump seem to be the worst alternative for those involved in policy making. When that change I expect it to be too late. Then we will have both a real recess, and economic wars for resources. The 'best' thing that can be said for war is that it usually brings a country together, and makes people ignore newfound poverty. It also open for exploitations on a grand scale, as war is too 'serious', to consider any environmentalism.

So it may work out for some few, depending on the acceleration of global warming, but for the overwhelming part of the world it won't. IPCC prognosis's is constantly losing ground to reality, and I foresee an acceleration, don't need a time machine for that.

Are the Durban Climate Talks—or Climate Talks in General—Doomed?
 

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