Extended Data Fig. 1: The relationship between iceberg calving, ocean tides, line-of-sight ice mélange speeds, and glacier speeds.

The relationship between iceberg calving (black horizontal lines), (a) ocean tides, (b) line-of-sight ice mélange speeds and (c) glacier speeds with time ascending down along the y-axis in all panels. Most of the calving occurred during a spring tide when tidal amplitudes (mean difference between two high and two low tides each day) were high. Mélange speeds were similar in magnitude but more variable than glacier speeds, indicating proglacial mechanisms affect ice mélange flow. For nearly all calving events, an increase in mélange speeds occurred without coincident increase in glacier speeds; the sole exception was Aug 9 when a small calving event was precipitated by a partial loss of mélange flow coherence located downfjord of the sampled time-series.