The world’s largest iceberg, known as A23a, has finally started moving after being stuck to the ocean floor for over three decades. This massive ice island broke off from the Antarctic coastline in 1986 and quickly became grounded in the Weddell Sea. With an area of nearly 4,000 sq km (1,500 sq miles), it is more than twice the size of Greater London. After years of being stationary, A23a has recently begun drifting at a rapid pace and is now about to venture beyond Antarctic waters. This colossal iceberg, measuring around 400m (1,312 ft) in thickness, is a true marvel. To put it into perspective, the tallest skyscraper in Europe, the London Shard, stands at a mere 310m tall. A23a originated from the Filchner Ice Shelf during a mass outbreak of icebergs. Interestingly, it was during this time that a Soviet research station was present, highlighting just how long ago this calving event occurred. Despite fears of losing equipment, the tabular berg remained close to the coast and firmly anchored to the ocean floor. So, what has prompted A23a to start moving after almost four decades? According to Dr. Andrew Fleming, a remote sensing expert from the British Antarctic Survey, it seems that the time had simply come for the iceberg to decrease in size enough to lose its grip and begin its journey. The recent movement of A23a has been driven by winds and currents, propelling it past the northern tip of the Antarctic Peninsula. A23a’s progress will be closely monitored by scientists. If it were to ground at South Georgia, it could potentially disrupt the feeding routes of millions of seals, penguins, and seabirds that breed on the island. However, it’s important to recognize that icebergs have a significant impact on the environment beyond just being a hazard. As they melt, they release mineral dust that provides nutrients for the base of ocean food chains. These icebergs are a source of life and biological activity, as noted by Dr Catherine Walker from the Woods Hole Oceanographic Institution.
