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Arctic Yearbook 2012
Humpert and Raspotnik
285
situation; assess the economic feasibility, and identify economic risk factors; and take measure of
behavioral uncertainties, including changing global trade patterns and emerging geopolitical
considerations.
Environmental and Climatic
Uncertainties
The Arctic Ocean is on an accelerating
trajectory to a new, seasonally ice-free state. The
Intergovernmental Panel on Climate Change
(IPCC) estimates that over the next century,
Arctic temperature rises will exceed the global
annual mean by a factor of four and will range
between 4.3 degrees Celsius (°C) and 11.4°C in
the winter and 1.2°C and 5.3°C in the summer
(Meehl et al., 2007). In the summer of 2007, the
Arctic witnessed a dramatic sea-ice collapse due to above average temperatures, strong winds, and
changes in ocean circulation. The ice has since failed to rebound to pre-2007 levels and may have
passed a tipping point beyond which rising air temperatures are no longer the primary cause of ice
loss, and where “self destructive dynamics take over” (Anderson, 2009: 89). During the 2012 melt
season Arctic sea ice declined yet again at a remarkable pace and a new record low for ice extent,
area, and volume was set.
Studies differ widely in their predictions of when summer sea ice will melt completely. Prior to the
events of 2007, the IPCC forecasted an ice-free Arctic for the latter part of the 21
st
century (Meehl et
al., 2007). The panel reported “the projected reduction [in global sea ice cover] is accelerated in the
Arctic, where some models project summer sea ice cover to disappear entirely in the high-emission
A2 scenario in the latter part of the 21
st
century” (Meehl et al., 2007: 750).
Yet studies published since the sea ice collapse of 2007 expect a dramatic reduction of summer ice in
the first half of the 21
st
century. In an interview with National Geographic, Mark Serreze from the
National Snow and Ice Data Center (NSIDC) in Boulder, Colorado stated “we are on track to see an
ice-free summer by 2030 (as cited in Vidal, 2011). A study by Wang & Overland, which combined