Arctic Ocean gravity, geoid and sea-ice freeboard heights from ICESat and GRACE

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

ICESat laser measurements provide a high-resolution mapping of the sea-ice surface of the Arctic Ocean, which can be inverted to determine gravity anomalies and sea-ice freeboard heights by a "lowest-level'' filtering scheme. In this paper we use updated terrestrial gravity data from the Arctic Gravity Project in combination with GRACE gravity field models to derive an improved Arctic geoid model. This model is then used to convert ICESat measurements to sea-ice freeboard heights with a coarse lowest-level surface method. The derived freeboard heights show a good qualitative agreement to the coverage of multi-year sea-ice; however, comparison to an airborne lidar underflight north of Greenland shows that the lowest-level filtering scheme may introduce a bias. We finally use the ICESat and GRACE results to derive new gravity anomalies by Fourier inversion. The satellite-only gravity field shows all major tectonic features of the Arctic Ocean, and has an accuracy of 6 mGal compared to recent airborne gravity data, illustrating the usefulness of ICESat data for gravity field determination.
Original languageEnglish
JournalGeophysical Research Letters
Volume32
Issue number21
ISSN0094-8276
Publication statusPublished - 2005

Cite this

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title = "Arctic Ocean gravity, geoid and sea-ice freeboard heights from ICESat and GRACE",
abstract = "ICESat laser measurements provide a high-resolution mapping of the sea-ice surface of the Arctic Ocean, which can be inverted to determine gravity anomalies and sea-ice freeboard heights by a {"}lowest-level'' filtering scheme. In this paper we use updated terrestrial gravity data from the Arctic Gravity Project in combination with GRACE gravity field models to derive an improved Arctic geoid model. This model is then used to convert ICESat measurements to sea-ice freeboard heights with a coarse lowest-level surface method. The derived freeboard heights show a good qualitative agreement to the coverage of multi-year sea-ice; however, comparison to an airborne lidar underflight north of Greenland shows that the lowest-level filtering scheme may introduce a bias. We finally use the ICESat and GRACE results to derive new gravity anomalies by Fourier inversion. The satellite-only gravity field shows all major tectonic features of the Arctic Ocean, and has an accuracy of 6 mGal compared to recent airborne gravity data, illustrating the usefulness of ICESat data for gravity field determination.",
author = "Ren{\'e} Forsberg and Henriette Skourup",
year = "2005",
language = "English",
volume = "32",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "Wiley-Blackwell",
number = "21",

}

Arctic Ocean gravity, geoid and sea-ice freeboard heights from ICESat and GRACE. / Forsberg, René; Skourup, Henriette.

In: Geophysical Research Letters, Vol. 32, No. 21, 2005.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Arctic Ocean gravity, geoid and sea-ice freeboard heights from ICESat and GRACE

AU - Forsberg, René

AU - Skourup, Henriette

PY - 2005

Y1 - 2005

N2 - ICESat laser measurements provide a high-resolution mapping of the sea-ice surface of the Arctic Ocean, which can be inverted to determine gravity anomalies and sea-ice freeboard heights by a "lowest-level'' filtering scheme. In this paper we use updated terrestrial gravity data from the Arctic Gravity Project in combination with GRACE gravity field models to derive an improved Arctic geoid model. This model is then used to convert ICESat measurements to sea-ice freeboard heights with a coarse lowest-level surface method. The derived freeboard heights show a good qualitative agreement to the coverage of multi-year sea-ice; however, comparison to an airborne lidar underflight north of Greenland shows that the lowest-level filtering scheme may introduce a bias. We finally use the ICESat and GRACE results to derive new gravity anomalies by Fourier inversion. The satellite-only gravity field shows all major tectonic features of the Arctic Ocean, and has an accuracy of 6 mGal compared to recent airborne gravity data, illustrating the usefulness of ICESat data for gravity field determination.

AB - ICESat laser measurements provide a high-resolution mapping of the sea-ice surface of the Arctic Ocean, which can be inverted to determine gravity anomalies and sea-ice freeboard heights by a "lowest-level'' filtering scheme. In this paper we use updated terrestrial gravity data from the Arctic Gravity Project in combination with GRACE gravity field models to derive an improved Arctic geoid model. This model is then used to convert ICESat measurements to sea-ice freeboard heights with a coarse lowest-level surface method. The derived freeboard heights show a good qualitative agreement to the coverage of multi-year sea-ice; however, comparison to an airborne lidar underflight north of Greenland shows that the lowest-level filtering scheme may introduce a bias. We finally use the ICESat and GRACE results to derive new gravity anomalies by Fourier inversion. The satellite-only gravity field shows all major tectonic features of the Arctic Ocean, and has an accuracy of 6 mGal compared to recent airborne gravity data, illustrating the usefulness of ICESat data for gravity field determination.

M3 - Journal article

VL - 32

JO - Geophysical Research Letters

JF - Geophysical Research Letters

SN - 0094-8276

IS - 21

ER -