Global climate change is one of the most important issues facing modern society.
Global mean surface air temperatures have increased approximately 0.68C over
the past century resulting in the retreat of glaciers, thawing of permafrost and
sea ice, increase in river discharge and alteration of terrestrial and aquatic
ecosystems in ways that demand both immediate and long-term societal response
(Overpeck et al. 1997; IPCC 2001; Peterson et al. 2002; Romanovsky et al. 2002;
ACIA 2004; Hinzman et al. 2005; Stern Review 2006).
