Arctic Iceberg Traffic Jumps 6.4% Per Decade, Reshaping Deep-Sea Biodiversity
Updated
Updated · Nature.com · Jun 10
Arctic Iceberg Traffic Jumps 6.4% Per Decade, Reshaping Deep-Sea Biodiversity
3 articles · Updated · Nature.com · Jun 10
Summary
Four decades of Fram Strait records show iceberg sightings rose about 6.4% per decade, with frequencies stepping up from 4.9% before 2000 to 25.6% afterward.
Seafloor surveys at 2,500 meters found dropstone density increased from 1.59 to 1.93 per square meter between 2015 and 2017, alongside higher richness and density of attached sponges and cnidarians.
Backtracking linked western Fram Strait icebergs mainly to northeast Greenland glaciers, where destabilization around 2003 matched the traffic increase; eastern sightings pointed largely to Russia's High Arctic, though satellite coverage there is sparse.
Model tests suggest stronger calving was only part of the shift: a more mobile, reduced sea-ice cover sped iceberg drift and raised simulated Fram Strait crossings by about 69% in the west and 56% in the east after 2005.
The study says warming-driven iceberg export is creating more hard-bottom habitat far from calving fronts while also increasing navigational hazards as Arctic shipping expands.