Application of first- and second-order adjoint methods to glacial isostatic adjustment incorporating rotational feedbacks
Year: 2024
Type: article
Abstract: SUMMARY This paper revisits and extends the adjoint theory for glacial isostatic adjustment (GIA) of Crawford et al. (2018). Rotational feedbacks are now incorporated, and the application of the second-order adjoint method is described for the first time. The first-order adjoint method provides an efficient means for computing sensitivity kernels for a chosen objective functional, while the second-order adjoint method provides second-derivative information in the form of Hessian kernels. These latter kernels are required by efficient Newton-type optimization schemes and within methods for quantifying uncertainty for non-linear inverse problems. Most importantly, the entire theory has been reformulated so as to simplify its implementation by others within the GIA community. In particular, the rate-formulation for the GIA forward problem introduced by Crawford et al. (2018) has been replaced with the conventional equations for modelling GIA in laterally heterogeneous earth models. The implementation of the first- and second-order adjoint problems should be relatively easy within both existing and new GIA codes, with only the inclusions of more general force terms being required.
DOI: 10.1093/gji/ggae388
Language: English
Subfield: Oceanography
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,377
Awards: G1796849936, Collaborative Research: Imaging the 3D Viscosity Structure of the Antarctic Mantle with Existing Observations from GPS and Relative Sea Level, G460001484, G4816011601, NSFGEO-NERC: Adjoint tomography of mantle viscosity using deglacial sea level observations, G6182750077, NSFGEO-NERC: Adjoint tomography of mantle viscosity using deglacial sea level observations, Next-Generation Modelling of Glacial Isostatic Adjustment
OpenAlex ID: W4404159550