BedMachine v3: Complete Bed Topography and Ocean Bathymetry Mapping of Greenland From Multibeam Echo Sounding Combined With Mass Conservation.


Type
Article
Change log
Abstract

Greenland's bed topography is a primary control on ice flow, grounding line migration, calving dynamics, and subglacial drainage. Moreover, fjord bathymetry regulates the penetration of warm Atlantic water (AW) that rapidly melts and undercuts Greenland's marine-terminating glaciers. Here we present a new compilation of Greenland bed topography that assimilates seafloor bathymetry and ice thickness data through a mass conservation approach. A new 150 m horizontal resolution bed topography/bathymetric map of Greenland is constructed with seamless transitions at the ice/ocean interface, yielding major improvements over previous data sets, particularly in the marine-terminating sectors of northwest and southeast Greenland. Our map reveals that the total sea level potential of the Greenland ice sheet is 7.42 ± 0.05 m, which is 7 cm greater than previous estimates. Furthermore, it explains recent calving front response of numerous outlet glaciers and reveals new pathways by which AW can access glaciers with marine-based basins, thereby highlighting sectors of Greenland that are most vulnerable to future oceanic forcing.

Description
Keywords
Greenland, bathymetry, glaciology, mass conservation, multibeam echo sounding, radar echo sounding
Journal Title
Geophys Res Lett
Conference Name
Journal ISSN
0094-8276
1944-8007
Volume Title
44
Publisher
American Geophysical Union (AGU)
Sponsorship
Natural Environment Research Council (NE/H020667/1)
NERC (NER/T/S/2000/00986)
Natural Environment Research Council (NE/D001986/1)
Natural Environment Research Council (NE/K004999/1)
NERC (via University of Bristol) (unknown)
NERC (unknown)