Figure 6.6

Figure 6.6. Summer surface air temperature change over the Arctic (left) and annual minimum ice thickness and extent for Greenland and western arctic glaciers (right) for the LIG from a multi-model and a multi-proxy synthesis. The multi-model summer warming simulated by the National Center for Atmospheric Research (NCAR) Community Climate System Model (CCSM), 130 ka minus present (Otto-Bliesner et al., 2006b), and the ECHAM4 HOPE-G (ECHO-G) model, 125 ka minus pre-industrial (Kaspar et al., 2005), is contoured in the left panel and is overlain by proxy estimates of maximum summer warming from terrestrial (circles) and marine (diamonds) sites as compiled in the syntheses published by the CAPE Project Members (2006) and Kaspar et al. (2005). Extents and thicknesses of the Greenland Ice Sheet and eastern Canadian and Iceland glaciers are shown at their minimum extent for the LIG as a multi-model average from three ice models (Tarasov and Peltier, 2003; Lhomme et al., 2005a; Otto-Bliesner et al., 2006a). Ice core observations (Koerner, 1989; NGRIP, 2004) indicate LIG ice (white dots) at Renland (R), North Greenland Ice Core Project (N), Summit (S, Greenland Ice Core Project and Greenland Ice Sheet Project 2) and possibly Camp Century (C), but no LIG ice (black dots) at Devon (De) and Agassiz (A) in the eastern Canadian Arctic. Evidence for LIG ice at Dye-3 (D) in southern Greenland is equivocal (grey dot; see text for detail).