The influence of lateral Earth structure on inferences of global ice volume during the Last Glacial Maximum

• DOI: 10.1016/j.quascirev.2022.107644
• Publication Date: 2022-07-20T22:33:15Z
• Authors: Linda Pan; Glenn A. Milne; Konstantin Latychev; Samuel L. Goldberg; Jacqueline Auster...; Mark J. Hoggard; Jerry X. Mitrovica
• Keywords: Post-glacial rebound; Last Glacial Maximum

The mapping between far-field relative sea level (RSL) records and changes in ice volume or global mean (GMSL) involves a correction for glacial isostatic adjustment (GIA). This is thus sensitive to uncertainties inherent GIA modeling, including the spatio-temporal history of mass viscoelastic Earth structure. Here, we investigate effect incorporating lateral variations structure on predicting order determine if this source model uncertainty significantly impacts estimates at Last Glacial Maximum (LGM). We consider set forty 3-D simulations that sample different parameters: adopted lithospheric thickness, seismic velocity used infer temperature variations, scaling factor conversion from viscosity, spherically averaged "background" viscosity profile. In addition, results based two histories. present maps differences these 1-D LGM, as well RSL histories 5 locations have been previously considered LGM: Barbados, sites Great Barrier Reef, Bonaparte Gulf Sunda Shelf. find difference inferences LGM models peaks Barbados with ranging ∼2.5 11 m, ∼6–7 m. At other sites, ranges ∼2 −8 ∼0 −3 After comparing pairs simulations, conclude that, general, impact varying model, thickness background significant sites. Finally, while do not consistent signal above would help reconcile volumes estimated studies those summing regional sheet reconstructions, nonetheless large enough analyses far field sheets should include models.