Preprints
https://doi.org/10.5194/esdd-6-1605-2015
https://doi.org/10.5194/esdd-6-1605-2015
07 Sep 2015
 | 07 Sep 2015
Status: this preprint was under review for the journal ESD but the revision was not accepted.

The eigenvalue problem for ice-shelf vibrations: comparison of a full 3-D model with the thin plate approximation

Y. V. Konovalov

Abstract. Ice-shelf forced vibration modelling is performed using a full 3-D finite-difference elastic model, which also takes into account sub-ice seawater flow. The ocean flow in the cavity is described by the wave equation; therefore, ice-shelf flexures result from hydrostatic pressure perturbations in sub-ice seawater layer. Numerical experiments have been carried out for idealized rectangular and trapezoidal ice-shelf geometries. The ice-plate vibrations are modelled for harmonic ingoing pressure perturbations and for high-frequency spectra of the ocean swells. The spectra show distinct resonance peaks, which demonstrate the ability to model a resonant-like motion in the suitable conditions of forcing. The spectra and ice-shelf deformations obtained by the developed full 3-D model are compared with the spectra and the deformations modelled by the thin-plate Holdsworth and Glynn model (1978). The main resonance peaks and ice-shelf deformations in the corresponding modes, derived by the full 3-D model, are in agreement with the peaks and deformations obtained by the Holdsworth and Glynn model. The relative deviation between the eigenvalues (periodicities) in the two compared models is about 10 %. In addition, the full model allows observation of 3-D effects, for instance, the vertical distribution of the stress components in the plate. In particular, the full model reveals an increase in shear stress, which is neglected in the thin-plate approximation, from the terminus towards the grounding zone with a maximum at the grounding line in the case of the considered high-frequency forcing. Thus, the high-frequency forcing can reinforce the tidal impact on the ice-shelf grounding zone causing an ice fracture therein.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Y. V. Konovalov
 
Status: closed
Status: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement
 
Status: closed
Status: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement
Y. V. Konovalov
Y. V. Konovalov

Viewed

Total article views: 1,373 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
974 306 93 1,373 91 111
  • HTML: 974
  • PDF: 306
  • XML: 93
  • Total: 1,373
  • BibTeX: 91
  • EndNote: 111
Views and downloads (calculated since 07 Sep 2015)
Cumulative views and downloads (calculated since 07 Sep 2015)

Cited

Saved

Latest update: 10 Oct 2024
Download
Altmetrics