Greenland’s hidden fjord floors in BedMachine v3
A 150 m Greenland bed and fjord map raises sea-level potential by 7 cm and shows 30–100% more glaciers can meet warm Atlantic Water.
Source
BedMachine v3: Complete Bed Topography and Ocean Bathymetry Mapping of Greenland From Multibeam Echo Sounding Combined With Mass Conservation
Study at a glance
- Design
- Other — Mass-conservation bed mapping combining ice-penetrating radar and ocean bathymetry
- N
- Greenland-wide BedMachine v3 product; volume 2.99×10^6 km³ — not a sample N
- Population
- Greenland Ice Sheet bed topography and adjacent ocean bathymetry
- Outcome
- Ice volume, sea-level potential (7.42 m), and ocean access to glacier fronts
Structured fields used in claim comparison tables when every cited study has a complete layer.
What they did
Authors combined IceBridge radar, mass conservation where ice flows faster than 50 m/yr, and 30 bathymetry sources including OMG multibeam to map bed and fjords within 50 km of the coast at up to 150 m.
What they found
Ice volume is 2.99±0.02×10^6 km³; sea-level potential 7.42±0.05 m (7 cm above prior). Of 243 glaciers, 67 connect to ocean deeper than 200 m. Retreat patterns match retrograde beds; v2 beds were often ~100 m too high.
The limits
What it doesn't show
True resolution is coarser (~1 km) where kriging/RTopo-2 fill gaps; radar thickness uncertainty is ~50 m; thinning since 2003–2008 is ignored except where it exceeds that error.
Key terms
- Mass conservation
- Inferring ice thickness from flux divergence where velocity is well observed.
- Atlantic Water
- Warm subsurface ocean water typically deeper than 200–300 m.
- Retrograde bed
- Bed that deepens inland, favoring unstable retreat.
- OMG
- Oceans Melting Greenland ship and airborne bathymetry campaign.
- BedMachine
- Greenland ice-thickness and bed product built with mass conservation.
Flashcards
Research intelligence for this paper
See its role on concept claims, tensions it is part of, placement history, and related discoveries.
Quiz yourself
v3 Greenland sea-level potential:
Common questions
Sea-level potential in v3?
7.42 ± 0.05 m, 7 cm higher than before.
Grid spacing?
150 m (true resolution 150 m–1 km by data type).
How many glaciers reach >200 m ocean pathways?
67 of 243, versus 32 in B2013.
Why map fjord sills?
Sills can block warm Atlantic Water from calving fronts.
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