In-situ quantification of ice rheology and direct measurement of the Raymond Effect at Summit, Greenland using a phase-sensitive radar

54Citations
Citations of this article
78Readers
Mendeley users who have this article in their library.

Abstract

The Glen exponent n characterizes the stress-dependence of ice deformation, directly influencing the rate at which ice masses respond to external forcing. The slow deformation in large ice-sheets makes laboratory rheometry at representative strain-rates difficult. We develop a new technique to estimate n in-situ, deploying a phase-sensitive radar to measure vertical strain rates of around 10 -4 yr -1 within the top 1000 m of ice across ice divides at Summit and NEEM, Greenland. A fluid-dynamical feature, the Raymond Effect, predicts strong vertical strain-rate variation across divides over distances of a few ice-thicknesses. We achieve sufficient resolution to show this pattern, enabling us to estimate n = 4.5 by inverting our observations with flow modelling. This is higher than values previously used but consistent with other indirect measurements, implying laboratory measurements do not explore the full range of ice rheology and the consequent possibility of a greater sensitivity and responsiveness in ice-sheet dynamics. Copyright 2011 by the American Geophysical Union.

References Powered by Scopus

Ice sheet grounding line dynamics: Steady states, stability, and hysteresis

887Citations
N/AReaders
Get full text

Creep and fracture of ice

482Citations
N/AReaders
Get full text

Past and future grounding-line retreat of the West Antarctic Ice Sheet

375Citations
N/AReaders
Get full text

Cited by Powered by Scopus

A synthesis of the basal thermal state of the Greenland Ice Sheet

132Citations
N/AReaders
Get full text

Antarctic ice rises and rumples: Their properties and significance for ice-sheet dynamics and evolution

110Citations
N/AReaders
Get full text

Instruments and methods: A ground-based radar for measuring vertical strain rates and time-varying basal melt rates in ice sheets and shelves

86Citations
N/AReaders
Get full text

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Cite

CITATION STYLE

APA

Gillet-Chaulet, F., Hindmarsh, R. C. A., Corr, H. F. J., King, E. C., & Jenkins, A. (2011). In-situ quantification of ice rheology and direct measurement of the Raymond Effect at Summit, Greenland using a phase-sensitive radar. Geophysical Research Letters, 38(24). https://doi.org/10.1029/2011GL049843

Readers' Seniority

Tooltip

PhD / Post grad / Masters / Doc 39

63%

Researcher 18

29%

Professor / Associate Prof. 3

5%

Lecturer / Post doc 2

3%

Readers' Discipline

Tooltip

Earth and Planetary Sciences 45

79%

Physics and Astronomy 4

7%

Engineering 4

7%

Environmental Science 4

7%

Article Metrics

Tooltip
Mentions
References: 2

Save time finding and organizing research with Mendeley

Sign up for free