Iceberg B-15 - Effect On Antarctic Ecology

Effect On Antarctic Ecology

On April 10, 2005 B-15A hit the Drygalski ice tongue, a projection of the fast-moving David Glacier that flows through Antarctica's mountainous Victoria Land coastal region, breaking off an 8 km² (3 mi²) section of the ice tongue. This collision with the Drygalski tongue forced a redrawing of Antarctic maps.

B-15A prevented ocean currents and winds from assisting in the 2004–2005 summer break-up of the sea ice in McMurdo Sound, and was an obstacle to the annual resupply ships to three research stations. The floe was expected to cause a catastrophic decline in the population of Adelie Penguins, as it added considerable distances which parent penguins must travel back from the sea to their chicks. Weddell seals and Skuas are also inhabitants of McMurdo Sound and their populations may have been affected as well.

In October 2006, it was noted by MacAyeal et al. (2006) that a large storm in the Gulf of Alaska generated a trans-Pacific ocean swell that may have contributed to breaking B15-A into many pieces on October 27, 2005. The swell travelled 13,500 km (8,300 mi) from Alaska to Antarctica over six days. Scientists are studying this event as an example of how weather in one area can have effects in other parts of the world, and with concern over the effects on global warming. A more recent and detailed study by Martin et al. (2010), however, indicates that the iceberg breakup was principally caused by repeated grounding with near-coastal bathymetry near Cape Adare, Victoria Land.