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several steps in a broader push for climate justice, aiming to help Kivalina
residents draw attention to their situation and call for action from
government and corporate officials that had so far largely ignored them.
The media gave the lawsuit brief attention that quickly faded, and the
judge’s ruling was issued with little discussion or notice outside of certain
legal circles. Meanwhile, the people of Kivalina are still in danger from
the effects of climate change, in a situation that is going to become more
common throughout the world.
For roughly the past ten thousand years we have enjoyed a relatively
stable climate that has allowed for the development of agriculture and
civilization. Such stability is the exception, not the norm, when it comes to
the earth’s 4.54 billion-year history. The Earth has oscillated between long
periods of cooling (glaciations) and shorter periods of warming
(interglacials), sometimes undergoing radical climate variations within the
span of a century or even a decade. Evidence suggests that later
glaciations correspond with periodic shifts in the earth’s orbit, tilt, and
precession (movement of the axis), which can reduce the amount of
energy received at the poles. This small temperature perturbation, in turn,
can kickstart a glaciation through feedbacks: as ice builds, greenhouse
concentrations within the oceans are sequestered and reduced in the
atmosphere, and the ice reflects a greater amount of sunlight back to space
(the “albedo effect”). These processes maintain the cooling, and can create
the conditions for layer upon layer of cumulative ice sheets.
Glaciations then give way to warmer interglacial periods, which have
been correlated to increases in greenhouse gases in the atmosphere—trace
gases like carbon dioxide and methane that capture heat and can amplify
the initial orbital forcings. The sun’s light rays that are absorbed by
oceans, land, and vegetation are eventually given off as infrared radiation,
or heat energy. Due to their molecular structure (having three or more
atoms), greenhouse gases vibrate at frequencies that allow them to absorb
and emit this infrared radiation, sending a portion of that energy back to
the Earth’s surface. During certain periods this increased heat can hasten
the melting of glaciers, with the newly exposed landscape absorbing more
heat and releasing more greenhouse gases, potentially leading to an