Antarctic worms, sea spiders, urchins and other marine creatures living in near-shore shallow habitats are regularly pounded by icebergs. New data suggests this environment along the Antarctic Peninsula is going to get hit more frequently. This is due to an increase in the number of icebergs scouring the seabed as a result of shrinking winter sea ice.

Scientists from the British Antarctic Survey (BAS) show how the rate of iceberg scouring on the West Antarctic Peninsula seabed is affected by the duration of winter sea ice, which has dramatically declined (in space and time) in the region over the last few decades due to climate warming. This increase in iceberg disturbance on the seabed, where the majority of all Antarctic life occurs (80%), could have severe effects on the marine creatures living as deep as 500 meters underwater.

Ice disturbance has been recognized as a driving force in the structure of the Antarctic seabed animal communities. Iceberg scouring damages areas of the seabed creating space for a high diversity of animals to use; however, an increase in iceberg scour with the seabed would affect the type and number of marine creatures found on the seabed and may cause changes in the distributions of key species.

Many factors influence the probability of an iceberg impacting on an area of seabed. These include depth, seabed topography, proximity to an iceberg source, wind direction and tidal regimes.

The Antarctic Peninsula is an area of rapid climate change and has warmed faster than anywhere else in the Southern Hemisphere over the past half century. Climate records from the west coast of the Antarctic Peninsula show that air temperatures in this region have risen by nearly 3°C (5.4°F) during the last 50 years – several times the global average and only matched in Alaska.  *********

(Source and Photo Credits: British Antarctic Survey)