Trajectory of increased iceberg kill-off in West Antarctica’s shallows

Compared with low latitude coasts, many polar latitudes are still little impacted by intense and direct anthropogenic stressors. Climate forcing is now bringing rapid physical change to nearshore polar realms. In the shallow coastal waters adjacent to the United Kingdom’s Rothera Research Station in the West Antarctic Peninsula (WAP), 225 seabed markers at 5–25 m depth have been surveyed and replaced every year from 2002–2023 (75 markers at each of 5, 10 and 25 m). This is one of the longest continuously running marine disturbance experiments in the world, in one of Earth’s fastest changing environments. Different categories of sea ice are recorded (including when the sea surface freezes into fast ice) at Rothera since the 1980s, and losses of marine ice in both polar regions are one of the striking responses to a warming planet1. Five to ten years of seabed marker hit rate data (marker broken or moved) showed that reduced sea ice cover is correlated with disturbance and mortality on the seabed2,3. Barnes et al. report long-term monitoring of seasonal sea ice duration and seabed iceberg scouring at a West Antarctic Peninsula site, projecting that, by 2050, there will be negligible seasonal sea ice and icebergs will scour half of the seabed, decimating life in Antarctica’s shallows.