Unraveling InSAR Observed Antarctic Ice-Shelf Flexure Using 2-D Elastic and Viscoelastic Modeling

Frontiers in Digital Humanities

Marsh, Oliver J.¹  Wild, Christian T.¹  Rack, Wolfgang¹ 

[1] Gateway Antarctica, University of Canterbury, New Zealand

关键词: Synthetic aperture radar (SAR);    Differential SAR interferometry (DInSAR);    numerical modelling;    TerraSAR-X;    Cryosat-2;    Antarctica;    Ice shelf;    grounding line;   

DOI  :  10.3389/feart.2018.00028

学科分类：社会科学、人文和艺术（综合）

来源: Frontiers

【 摘 要 】

Ice-shelf grounding zones link the Antarctic ice-sheets to the ocean. Differential interferometric synthetic aperture radar (DInSAR) is commonly used to monitor grounding-line locations, but also contains information on grounding-zone ice thickness, ice properties and tidal conditions beneath the ice shelf. Here, we combine in-situ data with numerical modelling of ice-shelf flexure to investigate 2-D controls on the tidal bending pattern on the Southern McMurdo Ice Shelf. We validate our results with 9 double-differential TerraSAR-X interferograms. It is necessary to make adjustments to the tidal forcing to directly compare observations with model output and we find that when these adjustments are small (< 1.5 cm) a viscoelastic model matches better, while an elastic model is more robust overall. Within landward embayments, where lateral stresses from surrounding protrusions damp the flexural response, a 2-D model captures behaviour that is missed in simple 1-D models. We conclude that improvements in current tide models are required to allow for the full exploitation of DInSAR in grounding-zone glaciology.

【 授权许可】

CC BY