World's Largest Iceberg A23a Begins Drifting

Almost a Trillion Ton Iceberg, Twice the Area of Greater London, Expected to Impact Ocean Environment

The world's largest iceberg, A23a, has been measured to have a mass of almost a trillion tons and an average thickness of over 280 meters.
A23a, which is more than twice the area of Greater London, broke off from the Antarctic coast in 1986 and was largely immobile for over 30 years.
Recently, A23a dislodged from the sea floor and began drifting, with its future trajectory likely to be decided in the coming weeks.
The iceberg's movement and eventual location will have significant impacts on the ocean environment, including deep mixing of seawater, bringing nutrients to the surface, and fertilizing the ocean.
Scientists have been able to measure the iceberg's dimensions using the European Space Agency's CryoSat-2 mission, which uses radar to sense how much of an iceberg's mass is above the waterline.