A complete map of Greenland ice velocity derived from satellite data collected over 20 years

• Published in: Journal of Glaciology
• Main Authors: JOUGHIN, IAN, SMITH, BEN E., HOWAT, IAN M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2017
• Subjects: Greenland; Ice Sheet; Journal of Glaciology
• Online Access: http://dx.doi.org/10.1017/jog.2017.73; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143017000739

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 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.