Precursor motion to iceberg calving at Jakobshavn Isbræ, Greenland, observed with terrestrial radar interferometry

• Published in: Journal of Glaciology
• Main Authors: SURUI XIE, TIMOTHY H. DIXON, DENIS VOYTENKO, DAVID M. HOLLAND, DENISE HOLLAND, TIANTIAN ZHENG
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2016
• Subjects: glacier calving; ice block rotation; Lagrangian coordinates; subsurface melting; terrestrial radar interferometry; Environmental sciences; GE1-350; Meteorology. Climatology; QC851-999; Greenland; Jakobshavn Isbræ; glacier; Jakobshavn; Jakobshavn isbræ; Journal of Glaciology
• Online Access: https://doi.org/10.1017/jog.2016.104; https://doaj.org/article/27ea2fdffaf14d6287906379bb5b6f4f

Time-varying elevations near the calving front of Jakobshavn Isbræ, Greenland were observed with a terrestrial radar interferometer (TRI) in June 2015. An ice block with surface dimensions of 1370 m × 290 m calved on 10 June. TRI-generated time series show that ice elevation near the calving front began to increase 65 h prior to the event, and can be fit with a simple block rotation model. We hypothesize that subsurface melting at the base of the floating terminus breaks the gravity-buoyancy equilibrium, leading to slow subsidence and rotation of the block, and its eventual failure.