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."
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.coolantarctica.com%2FAntarctica%2520fact%2520file%2Fscience%2F_derived%2Fglobal_warming.htm_txt_Map_bare_2.gif&hash=8d98ac60989f547f26dce488933b5256)
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. (http://www.coolantarctica.com/Antarctica%20fact%20file/science/global_warming.htm)
What role do the polar regions play in the Earth's climate. (http://www.awi.de/en/news/background/climate_change/should_changes_in_the_polar_regions_be_of_interest_to_us/) 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. (http://www.c2es.org/arctic_qa.cfm)
The Ecconomist 2011. Arctic sea ice is melting far faster than climate models predict. Why? (http://www.economist.com/node/21530079)