Deglaciation related features of the Earth's gravity field

Abstract

The Earth's gravity field is partly a consequence of the delayed rebound of previously glaciated regions and this is most readily seen in the negative anomalies over the Hudson Bay, Gulf of Bothnia and the Central Siberian Plateau. Globally the relation between deglaciation and gravity is complicated by the redistribution of the melted ice over the oceans and the deglaciation effects on gravity extend far beyond the boundaries of the former ice loads. In this paper we have computed the contribution to the observed potential of the redistribution of mass associated with the Late Pleistocene deglaciation and found that this is not an insignificant amount. In particular, this contribution exceeds that arising from the Earth's isostatically compensated topography. The observed potential has been corrected for both effects but while details in the geoid or gravity anomaly representation change, the power spectrum is not significantly modified. In particular, the decay of the corrected spectrum remains very similar to that observed. Show more