title: 21st-century evolution of Greenland outlet glacier velocities.
abstract: Earlier observations on several of Greenland's outlet glaciers, starting near the turn of the 21st century, indicated rapid (annual-scale) and large (>100%) increases in glacier velocity. Combining data from several satellites, we produce a decade-long (2000 to 2010) record documenting the ongoing velocity evolution of nearly all (200+) of Greenland's major outlet glaciers, revealing complex spatial and temporal patterns. Changes on fast-flow marine-terminating glaciers contrast with steady velocities on ice-shelf-terminating glaciers and slow speeds on land-terminating glaciers. Regionally, glaciers in the northwest accelerated steadily, with more variability in the southeast and relatively steady flow elsewhere. Intraregional variability shows a complex response to regional and local forcing. Observed acceleration indicates that sea level rise from Greenland may fall well below proposed upper bounds.
authors.affiliation: Earth and Space Sciences, University of Washington, Seattle, WA 98195, USA. twilap@uw.edu
authors.forename: T
authors.initials: T
authors.lastname: Moon
authors.forename: I
authors.initials: I
authors.lastname: Joughin
authors.forename: B
authors.initials: B
authors.lastname: Smith
authors.forename: I
authors.initials: I
authors.lastname: Howat