Deglaciation-induced spatially variable sea level change: a simple-model case study for the Greenland and Antarctic ice sheets

• Main Authors: Kuhn, Michael, Featherstone, Will, Makarynskyy, Oleg, Keller, W.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Multi-Science Publishing 2010
• Subjects: flooding; sea-level; mass centre; simulated melting; length of day; conceptual example; ice sheet; Antarctic; Greenland; Antarc*; Ice Sheet
• Online Access: https://hdl.handle.net/20.500.11937/35151

Some studies on deglaciation-induced sea-level change provide only a global average change, thus neglecting the fact that sea-level change is spatially variable. This is due mainly to the gravitational and visco-elastic feedback effects of the changing surface mass loads. In order to redress this apparent misconception and raise further awareness, we provide a conceptual example based on a simulated total melt of the Greenland and Antarctic ice sheets. This would give a global average sea-level change of about 64 m. However, due to the changed distribution of gravitating masses, the sea-level change depends on location, with a range of about -27 m to +79 m (i.e., sea-level will even fall in some places). This spatial dependency has several implications in the case of a total melt, such as >10% biases in global average sea-level change estimates based only on tide-gauge records, flooding of almost 10% of current land areas, an increase of the length of day by almost a half a second and a northward move of the centre of mass (geocentre) by about 20 m.