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A Complete Map of Greenland Ice Velocity Derived from Satellite Data Collected over 20 Years.

ABSTRACT: While numerous maps of Greenland ice flow velocity exist, most have gaps in coverage and/or accuracy is limited. We processed a large volume of synthetic aperture radar (SAR) and Landsat 8 imagery collected between 1995 and 2015 to produce a nearly complete map of ice flow velocity for Greenland at a far greater accuracy than most prior products. We evaluated the accuracy of this map by comparing it with a variety of measured and estimated velocities. For the slow-moving interior of the ice sheet, where estimates are determined from interferometric phase, the errors are ~2 m a-1 or better. For coastal areas, where estimates are determined entirely from speckle- or feature-tracking methods, errors are 2-3 m a-1, which is in good agreement with the estimated formal errors. Especially for the slow-moving majority of the ice sheet, this map provides an important source of data for numerous types of glaciological studies.

SUBMITTER: Joughin I

PROVIDER: S-EPMC6582972 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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A Complete Map of Greenland Ice Velocity Derived from Satellite Data Collected over 20 Years.

Joughin Ian I Smith Ben E BE Howat Ian M IM

The journal of glaciology 20171121 243

While numerous maps of Greenland ice flow velocity exist, most have gaps in coverage and/or accuracy is limited. We processed a large volume of synthetic aperture radar (SAR) and Landsat 8 imagery collected between 1995 and 2015 to produce a nearly complete map of ice flow velocity for Greenland at a far greater accuracy than most prior products. We evaluated the accuracy of this map by comparing it with a variety of measured and estimated velocities. For the slow-moving interior of the ice shee ...[more]

PMID: 31217636

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