Bed topography and lubrication inferred from surface measurements on fast-flowing ice streams

Throstur Thorsteinsson; Charles F. Raymond; G. Hilmar Gudmundsson; Robert A. Bindschandler; Paul Vornberger; Ian Joughin

doi:10.3189/172756503781830502

Bed topography and lubrication inferred from surface measurements on fast-flowing ice streams

Throstur Thorsteinsson^*, Charles F. Raymond, G. Hilmar Gudmundsson, Robert A. Bindschandler, Paul Vornberger, Ian Joughin

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

40 Citations (Scopus)

Abstract

Observations of surface elevation (s) and horizontal velocity components (u and v) are inverted to infer the topography (b) and lubrication (c) at the bed of an ice stream, based on a linearized perturbation theory of the transmission of flow disturbances through the ice thickness. Synthetic data are used to illustrate non-uniqueness in the inversion, but also demonstrate that effects of b and c can be separated when s, u and v are specified, even with added noise to simulate measurement errors. We have analyzed prominent short-horizontal-scale (∼2 km) features in topography and velocity pattern in a local 64 km by 32 km area of the surface of Ice Stream E, West Antarctica. Our preferred interpretation of bed conditions beneath the most prominent features on the surface identifies a deep trough in the basal topography with low lubrication in the base of the trough.

Original language	English
Pages (from-to)	481-490
Number of pages	10
Journal	Journal of Glaciology
Volume	49
Issue number	167
DOIs	https://doi.org/10.3189/172756503781830502
Publication status	Published - 2003
Externally published	Yes

Access to Document

10.3189/172756503781830502

Cite this

@article{4763ee861bda4ad396daa6bb84b6952f,

title = "Bed topography and lubrication inferred from surface measurements on fast-flowing ice streams",

abstract = "Observations of surface elevation (s) and horizontal velocity components (u and v) are inverted to infer the topography (b) and lubrication (c) at the bed of an ice stream, based on a linearized perturbation theory of the transmission of flow disturbances through the ice thickness. Synthetic data are used to illustrate non-uniqueness in the inversion, but also demonstrate that effects of b and c can be separated when s, u and v are specified, even with added noise to simulate measurement errors. We have analyzed prominent short-horizontal-scale (∼2 km) features in topography and velocity pattern in a local 64 km by 32 km area of the surface of Ice Stream E, West Antarctica. Our preferred interpretation of bed conditions beneath the most prominent features on the surface identifies a deep trough in the basal topography with low lubrication in the base of the trough.",

author = "Throstur Thorsteinsson and Raymond, {Charles F.} and Gudmundsson, {G. Hilmar} and Bindschandler, {Robert A.} and Paul Vornberger and Ian Joughin",

year = "2003",

doi = "10.3189/172756503781830502",

language = "English",

volume = "49",

pages = "481--490",

journal = "Journal of Glaciology",

issn = "0022-1430",

publisher = "Cambridge University Press",

number = "167",

}

TY - JOUR

T1 - Bed topography and lubrication inferred from surface measurements on fast-flowing ice streams

AU - Thorsteinsson, Throstur

AU - Raymond, Charles F.

AU - Gudmundsson, G. Hilmar

AU - Bindschandler, Robert A.

AU - Vornberger, Paul

AU - Joughin, Ian

PY - 2003

Y1 - 2003

N2 - Observations of surface elevation (s) and horizontal velocity components (u and v) are inverted to infer the topography (b) and lubrication (c) at the bed of an ice stream, based on a linearized perturbation theory of the transmission of flow disturbances through the ice thickness. Synthetic data are used to illustrate non-uniqueness in the inversion, but also demonstrate that effects of b and c can be separated when s, u and v are specified, even with added noise to simulate measurement errors. We have analyzed prominent short-horizontal-scale (∼2 km) features in topography and velocity pattern in a local 64 km by 32 km area of the surface of Ice Stream E, West Antarctica. Our preferred interpretation of bed conditions beneath the most prominent features on the surface identifies a deep trough in the basal topography with low lubrication in the base of the trough.

AB - Observations of surface elevation (s) and horizontal velocity components (u and v) are inverted to infer the topography (b) and lubrication (c) at the bed of an ice stream, based on a linearized perturbation theory of the transmission of flow disturbances through the ice thickness. Synthetic data are used to illustrate non-uniqueness in the inversion, but also demonstrate that effects of b and c can be separated when s, u and v are specified, even with added noise to simulate measurement errors. We have analyzed prominent short-horizontal-scale (∼2 km) features in topography and velocity pattern in a local 64 km by 32 km area of the surface of Ice Stream E, West Antarctica. Our preferred interpretation of bed conditions beneath the most prominent features on the surface identifies a deep trough in the basal topography with low lubrication in the base of the trough.

U2 - 10.3189/172756503781830502

DO - 10.3189/172756503781830502

M3 - Article

AN - SCOPUS:3843151611

SN - 0022-1430

VL - 49

SP - 481

EP - 490

JO - Journal of Glaciology

JF - Journal of Glaciology

IS - 167

ER -

Bed topography and lubrication inferred from surface measurements on fast-flowing ice streams

Abstract

Access to Document

Fingerprint

Cite this