Ice flux divergence anomalies on 79north Glacier, Greenland

Publication: Research - peer-reviewJournal article – Annual report year: 2011

Standard

Ice flux divergence anomalies on 79north Glacier, Greenland. / Seroussi, H.; Morlighem, M.; Rignot, E.; Larour, E.; Aubry, D.; Ben Dhia, H.; Kristensen, Steen Savstrup.

In: Geophysical Research Letters, Vol. 38, 2011, p. L09501.

Publication: Research - peer-reviewJournal article – Annual report year: 2011

Harvard

Seroussi, H, Morlighem, M, Rignot, E, Larour, E, Aubry, D, Ben Dhia, H & Kristensen, SS 2011, 'Ice flux divergence anomalies on 79north Glacier, Greenland' Geophysical Research Letters, vol 38, pp. L09501., 10.1029/2011GL047338

APA

Seroussi, H., Morlighem, M., Rignot, E., Larour, E., Aubry, D., Ben Dhia, H., & Kristensen, S. S. (2011). Ice flux divergence anomalies on 79north Glacier, Greenland. Geophysical Research Letters, 38, L09501. 10.1029/2011GL047338

CBE

Seroussi H, Morlighem M, Rignot E, Larour E, Aubry D, Ben Dhia H, Kristensen SS. 2011. Ice flux divergence anomalies on 79north Glacier, Greenland. Geophysical Research Letters. 38:L09501. Available from: 10.1029/2011GL047338

MLA

Vancouver

Seroussi H, Morlighem M, Rignot E, Larour E, Aubry D, Ben Dhia H et al. Ice flux divergence anomalies on 79north Glacier, Greenland. Geophysical Research Letters. 2011;38:L09501. Available from: 10.1029/2011GL047338

Author

Seroussi, H.; Morlighem, M.; Rignot, E.; Larour, E.; Aubry, D.; Ben Dhia, H.; Kristensen, Steen Savstrup / Ice flux divergence anomalies on 79north Glacier, Greenland.

In: Geophysical Research Letters, Vol. 38, 2011, p. L09501.

Publication: Research - peer-reviewJournal article – Annual report year: 2011

Bibtex

@article{3bac80bd66cf424eac21e7c79aa697c4,
title = "Ice flux divergence anomalies on 79north Glacier, Greenland",
publisher = "American Geophysical Union",
author = "H. Seroussi and M. Morlighem and E. Rignot and E. Larour and D. Aubry and {Ben Dhia}, H. and Kristensen, {Steen Savstrup}",
year = "2011",
doi = "10.1029/2011GL047338",
volume = "38",
pages = "L09501",
journal = "Geophysical Research Letters",
issn = "0094-8276",

}

RIS

TY - JOUR

T1 - Ice flux divergence anomalies on 79north Glacier, Greenland

A1 - Seroussi,H.

A1 - Morlighem,M.

A1 - Rignot,E.

A1 - Larour,E.

A1 - Aubry,D.

A1 - Ben Dhia,H.

A1 - Kristensen,Steen Savstrup

AU - Seroussi,H.

AU - Morlighem,M.

AU - Rignot,E.

AU - Larour,E.

AU - Aubry,D.

AU - Ben Dhia,H.

AU - Kristensen,Steen Savstrup

PB - American Geophysical Union

PY - 2011

Y1 - 2011

N2 - The ice flux divergence of a glacier is an important quantity to examine because it determines the rate of temporal change of its thickness. Here, we combine high-resolution ice surface velocity observations of Nioghalvfjerdsfjorden (79north) Glacier, a major outlet glacier in north Greenland, with a dense grid of ice thickness data collected with an airborne radar sounder in 1998, to examine its ice flux divergence. We detect large variations, up to 100 m/yr, in flux divergence on grounded ice that are incompatible with what we know of the glacier surface mass balance, basal mass balance and thinning rate. We examine the hypothesis that these anomalies are due to the three-dimensional flow of ice around and atop bumps and hollows in basal topography by comparing the flux divergence of three-dimensional numerical models with its surface equivalent. We find that three-dimensional effects have only a small contribution to the observed anomalies. On the other hand, if we degrade the spatial resolution of the data to 10 km the anomalies disappear. Further analysis shows that the source of the anomalies is not the ice velocity data but the interpolation of multiple tracks of ice thickness data onto a regular grid using a scheme (here block kriging) that does not conserve mass or ice flux. This problem is not unique to 79north Glacier but is common to all conventional ice thickness surveys of glaciers and ice sheets; and fundamentally limits the application of ice thickness grids to high-resolution numerical modeling of glacier flow. Citation: Seroussi, H., M. Morlighem, E. Rignot, E. Larour, D. Aubry, H. Ben Dhia, and S. S. Kristensen (2011), Ice flux divergence anomalies on 79north Glacier, Greenland, Geophys. Res. Lett., 38, L09501, doi: 10.1029/2011GL047338.

AB - The ice flux divergence of a glacier is an important quantity to examine because it determines the rate of temporal change of its thickness. Here, we combine high-resolution ice surface velocity observations of Nioghalvfjerdsfjorden (79north) Glacier, a major outlet glacier in north Greenland, with a dense grid of ice thickness data collected with an airborne radar sounder in 1998, to examine its ice flux divergence. We detect large variations, up to 100 m/yr, in flux divergence on grounded ice that are incompatible with what we know of the glacier surface mass balance, basal mass balance and thinning rate. We examine the hypothesis that these anomalies are due to the three-dimensional flow of ice around and atop bumps and hollows in basal topography by comparing the flux divergence of three-dimensional numerical models with its surface equivalent. We find that three-dimensional effects have only a small contribution to the observed anomalies. On the other hand, if we degrade the spatial resolution of the data to 10 km the anomalies disappear. Further analysis shows that the source of the anomalies is not the ice velocity data but the interpolation of multiple tracks of ice thickness data onto a regular grid using a scheme (here block kriging) that does not conserve mass or ice flux. This problem is not unique to 79north Glacier but is common to all conventional ice thickness surveys of glaciers and ice sheets; and fundamentally limits the application of ice thickness grids to high-resolution numerical modeling of glacier flow. Citation: Seroussi, H., M. Morlighem, E. Rignot, E. Larour, D. Aubry, H. Ben Dhia, and S. S. Kristensen (2011), Ice flux divergence anomalies on 79north Glacier, Greenland, Geophys. Res. Lett., 38, L09501, doi: 10.1029/2011GL047338.

U2 - 10.1029/2011GL047338

DO - 10.1029/2011GL047338

JO - Geophysical Research Letters

JF - Geophysical Research Letters

SN - 0094-8276

VL - 38

SP - L09501

ER -