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Significant Changes in the Arctic and Greenland

Posted on 01 September 2012 by Jerry

Unfortunately two new records are being set in the Arctic.  The first is that carbon dioxide levels at the Arctic have reached a new milestone by passing 400 parts per million.  The second is that the Arctic has lost more sea ice than at any time since satellite images were begun in 1979. 

The significance of this is that these trends are synergistic and scientists fear that at some point they will create a self-reinforcing sequence of events.  The potential consequent spiral of deterioration is described as follows.  As the carbon dioxide level rises in the Arctic, which is a leading indicator of what will happen with the rest of the planet, more heat is trapped by the atmosphere which causes a temperature rise.  As the temperature rises, more Arctic ice melts exposing more open water.  Open water does not reflect heat as efficiently as ice so water temperatures rise which melts even more ice.  As the water temperature rises, frozen seabed permafrost melts releasing large amounts of methane, a powerful greenhouse gas, into the atmosphere.  This in turn increases the atmosphere’s ability to trap heat, which increases the temperature of the Arctic, and so on.

Arctic sea ice grows in the winter and diminishes in the summer causing a seasonal ebb and flow.  Complicating winter replenishment is the declining thickness of “perennial” ice, which has been in place on a year-round basis for many years and is more resistant to melting.  When this ice begins to melt it makes summer ice even more vulnerable.  Diminishing the thickness and shrinking the area of the ice footprint reduces the summer ice volume to only 30% of its size in the 1980’s, as measured by submarines.

The Arctic is not the only region experiencing significant ice melt.  The scientific community is alarmed by Greenland’s extremely rapid ice melt in July of 2012.  In just four days the thawed ice area of Greenland jumped from 40% to 97%.  Up until now the highest melting as seen by satellites in the last 30 years has been about 55% of Greenland’s total area.  Mary Albert, an ice expert at Dartmouth College indicated this was the first significant melt at the site since 1889.  Ice core samples point to  a similar rapid ice melt in 1946, although to a much lesser degree.

The level of carbon dioxide in the atmosphere of the planet has been steadily rising since the beginning of the industrial age when it stood at 275 parts per million.  The planet’s carbon dioxide level now stands at 395 parts per million.  With the Arctic passing the level of 400 parts per million it means that in a few short years the rest of the world will follow.  Beyond the Arctic, these high readings have already been recorded in Greenland, Alaska, Norway, Iceland and Mongolia. 

Climate change deniers point out that carbon dioxide levels have changed over the millennia with CO2 having been above 400 parts per million about 800,000 years ago.  Today’s climate scientists point out that historically there were a number of factors that existed to produce those high concentrations.  Those factors are missing today.  Present concentrations can only be explained by acknowledging the contribution that human beings make to carbon dioxide levels as a result of industrialization.

Use the following links to obtain more information on this topic:

http://www.bbc.co.uk/news/science-environment-19393075?

http://www.sciencenews.org/view/generic/id/342767/title/greenland_enters_melt_mode

http://www.csmonitor.com/science/2012/0531/climate-change-arctic-passes-400-parts-per-million-milestone/

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