IPCC, 2007: The Arctic is expected to experience the greatest rates of warming compared with other world regions. In part, this is because ice has greater reflectivity (also known as albedo) than the ocean or land. Melting of highly reflective snow and ice reveals darker land and ocean surfaces, increasing absorption of the sun's heat and further warming the planet, especially in those regions. There is evidence that climate change is already having observable impacts in the Arctic."
Arctic warming due to global warming determines the fate of the whole planet.
The reason is the enormous potential positive amplifyihg Arctic climate feedbacks caused by Arctic amplifcation of global warming.
Arctic carbon feedbacks are mainly methane emissions and methane is 72 times more powerful than CO2 for 20 years after emission.
From latest 2012 research the Arctic is warming four times as fast as the global average.
The Siberian permafrost region warming is increasing. A 2009 review of Siberia climate change reports that Northern Eurasia winter temperatures have increased by more than 2C and summer temperatures by 1.35.C d since 1881.
Summer warming is a new phenomenon, starting to be observed very slightly over the past several decades. The Arctic warming had not been happening in the Summer being mainly a Winter-Spring change.
Very high Arctic climate sensitivity. May 2013 Science Evidence from Lake El’gygytgyn, in northeast (NE) Arctic Russia, shows that 3.6 to 3.4 million years ago, summer temperatures were ~8°C warmer than today, when the partial pressure of CO2 was ~400 parts per million.
Arctic amplification decreases temperature variance in northern mid- to high-latitudes Screen 2014
Arctic amplification is now recognized as an inherent aspect of trhe climate system past and present.
Subseasonal temperature variability has been observed to decrease over recent decades in the mid- to highlatitude Northern Hemisphere and this decline is projected to continue in the future. The historical decrease has been largest in autumn, when observed Arctic amplification has been most
pronounced, but model experiments project future decreases in mid- to high-latitude temperature variability in all seasons except summer. Models show larger projected warming in mid-latitudes than in high latitudes and increased summer variance
We have 2011 review Processes and impacts of Arctic amplification:
A research synthesis by Mark Serreze & Roger Barry. This reports
strong warming over the Arctic Ocean during the past decade in
autumn and winter, clearly associated with reduced sea ice extent,
AGW Observer Papers on Arctic amplification to 2012
(concise explanation by Skeptical Science)
For years we have watched the Arctic warming faster than the rest of the planet. This is the science of Arctic amplification that climate change models have predicted for years. Scientists have recently been able to say this is definitely happening and that the Arctic amplification is coming on stronger than models have projected.
A comprehensive paper on Arctic warming and albedo changes from satellite data was published in 2006 by J Comiso of NASA Arctic warming signals from satellite observations.
The 2011 SWIPA (snow & ice assessment) reports Beginning in 2002, extensive regions in the Arctic during late autumn have surface air temperature anomalies of more than 4 °C (Serreze et al., 2009).
A 2010 research paper by Screen and Simmonds convincingly explains and confirms Arctic amplification by summer sea ice extent loss, which indicates that both the rate of Arctic warming and sea ice loss will continue to increase.
A 30 year record by satellite of temperatures shows the Arctic has warmed nearly 4 X as fast as the global average over that period. 30 years of satellite data shows that the greatest warming has been in the Arctic. Temperatures in the atmosphere above the Arctic Ocean warmed by an average of 1.75 C (3.15° F) in 33 years. The fastest warming spot is in the Davis Strait, between the easternmost point on Baffin Island and Greenland. Temperatures there have warmed 2.89 C (about 5.2° F). (John Christy, University of Alabama in Huntsville, 2011). Globally averaged, Earth’s atmosphere has warmed about 0.45 Celsius (about 0.82° F) during the almost one-third of a century that sensors aboard NOAA and NASA satellites have measured the temperature of oxygen molecules in the air.
NASA temperature maps (to the right; click to enlarge) show the August trend and the change in Arctic temperatures over the past 30 years. James Hansen for NASA reports Jan 2012 that since the 70s, global warming seems to have been steady and in the range of about 0.15 to 0.175 degrees per decade - maximum of 0.2 degrees per decade. Warming anomaly in the Arctic was up to 4.7 degrees for average over 2011 see Figure 1, with up to 6.6 degrees in summer, see Figure 4.
The Danish Meteorological Institute DMI has a long record of high Arctic temperatures that covered in detail by Skeptical Science shows While summer maximums have showed little trend, the annual average Arctic temperature has risen sharply in recent decades. This is indicated both by the GISS, DMI data and other high latitude data sets. Most of the area above 80N is (currently) still covered in permanent sea ice. In the Arctic Summer when the surface ice is melting, the air temperature close to the surface is limited by this ice melt temperature to just above zero degrees C (Rigor 2000). This is why the Summer air temperatures have not varied much over the entire instrumental period.
2012 research Response of N Hemispheric Air Temperature to Arctic Sea Ice Decline
shows dramatic high NH latitude winter warming due to sea ice decline- little Summer effect.
March 2013 research explains the large difference in Arctic Winter and Summer warming which is at least a 4 fold difference now. The model research indicates a large difference will persist even in the absence of summer sea ice.
Loss of Arctic albedo
Scientists say that the main factor in the accelerating rate of Arctic warming is the loss of albedo and the heat gain resulting from the accelerating Arctic sea ice loss. This section of the WWF Arctic Feedbacks report explains how loss of sea ice albedo amplifies Arctic warming. In fact, where the summer sea ice is open, the Arctic temperature increase is greatest.
Black carbon (soot) deposited on Arctic snow from Northern hemisphere air pollution is a significant cause of albedo loss.
A winter thermal inversion adds to the amplification.
Water flowing into the Arctic Ocean from the Atlantic Ocean is about 2°C warmer today than it has been for at least 2,000 years, from Arctic warming amplification (so another feedback), according to a Science paper, Enhanced Modern Heat Transfer to the Arctic by Warm Atlantic Water, by R. Spielhagen et al., January 2011.
Another factor in Arctic amplification is a 2011 finding by C. Kinnard that "early 21st-century temperatures of Atlantic water entering the Arctic Ocean are unprecedented over the past 1450 years and are presumably linked to the Arctic amplification of global warming."
Some global warming emissions (methane, tropospheric ozone, black carbon) concentrate over the Arctic and may be adding to Arctic amplification (Short-lived pollutants in the Arctic: Their climate impact, P. K. Quinn et al, 2008). Atmospheric methane is concentrated over the poles, especially the Arctic (hydroxyl is not efficient at removing methane over the cold regions). The Svalbard atmospheric monitoring site has been recording a recent increase in Arctic methane concentration.
Sea surface temperature increases for the Arctic are highest over the continental shelves and that is where the vulnerable methane hydrate is located.
How will Arctic amplification affect the rate of Arctic warming, northern hemisphere warming, and global warming?
We do have one published indication of how the loss of Arctic summer sea ice will increase the rate of Arctic warming, from David Lawrence in 2008.
He found that "during episodes of rapid sea-ice loss in the past, the rate of Arctic land warming is 3.5 times greater than the average 21st century warming rates predicted in global climate models. While this warming is largest over the ocean, the simulations suggest that it can penetrate as far as 900 miles inland. The simulations also indicate that the warming acceleration during such events is especially pronounced in autumn. The decade during which a rapid sea-ice loss event occurs could see autumn temperatures warm by as much as 5 degrees C (9ºF) along the Arctic coasts of Russia, Alaska, and Canada."
This is highly significant to the increase in methane emissions from thawing permafrost and destabilizing methane hydrates.
The 2007 record Arctic summer sea ice loss resulted in a large increase in surface temperature of exposed ocean water. The greatest warming was 5C and right over the shallow East Siberian Arctic shelf methane hydrates.
At the 2011 AGU meeting –Dr. Jennifer presenting Francis of Rutgers University, in her talk “Does Arctic Amplification Fuel Extreme Weather in Mid-Latitudes?” said “The question is not whether sea ice loss is affecting the large-scale atmospheric circulation…it’s how can it not?”
Though there is no question that Arctic amplification will be felt by the rest of the planet, models so far are unable to forecast what Arctic amplification will do directly to northern hemisphere and global climate change. However, the increase in Arctic methane emissions is inevitable and will definitely increase the rate of warming, especially the warming that will continue to be greater in the northern hemisphere.