... described as deformation of the surface of equal gravitational potential, the geoid. The state of isostatic disequilibrium in regions with past ice-mass loss results in a geoid low; the adjustment process, meaning an influx of mantle material, reduces the geoid low. A well-known example is found in north-eastern Canada, where a geoid low of about 40 m indicates that the earth has not fully regained isostatic equilibrium after the retreat of the Laurentide ice sheet. However, in this region, at least half of the geoid depression is attributed to a density anomaly driving mantle convection  (e.g. Mitrovica & Vermeersen, 2002) . The geoid-height changes associated with present-day glacial changes are dominated by the direct attraction of the ice and water masses involved. Changes due to the earth's elastic response are comparatively small.

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