Journal of Glaciology (Dec 2016)

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

  • SURUI XIE,
  • TIMOTHY H. DIXON,
  • DENIS VOYTENKO,
  • DAVID M. HOLLAND,
  • DENISE HOLLAND,
  • TIANTIAN ZHENG

DOI
https://doi.org/10.1017/jog.2016.104
Journal volume & issue
Vol. 62
pp. 1134 – 1142

Abstract

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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.

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