A 40-mile-wide iceberg in Antarctica, the largest in the world and weighing a whopping 1 trillion tons, is on the move after decades grounded to the sea floor, the British Antarctic Survey (BAS) announced.
The world’s largest and oldest iceberg, A23a, has come to a halt less than 60 miles from the remote South Georgia Island in the South Atlantic, with surveyors warning that the dangers are far from over.
The British Antarctic Survey reports that the massive iceberg originally broke free from Antarctica’s ice shelf in 1986 but only began moving toward the island in 2020.
NOAA’s GOES East satellite captured imagery of the iceberg slowly drifting northeastward away from Antarctica and toward South Georgia Island, but in February, it ran aground southwest of the island.
“If the iceberg stays grounded, we don’t expect it to significantly affect the local wildlife of South Georgia. In the last few decades, the many icebergs that end up taking this route through the Southern Ocean soon break up, disperse, and melt. Commercial fisheries have been disrupted in the past, however, and as the berg breaks into smaller pieces, this might make fishing operations in the area both more difficult and potentially hazardous,” Dr. Andrew Meijers, an oceanographer at the British Antarctic Survey, said in a statement.
ANTARCTICA’S ‘DOOMSDAY GLACIER’ IS MELTING AWAY DIFFERENTLY THAN SCIENTISTS FIRST THOUGHT
World’s largest iceberg grounds near sub-Antarctic Island of South Georgia
(Theresa Gossman, British Antarctic Survey / FOX Weather)
Despite coming to a halt, A23a’s future remains uncertain, as warm waters and waves are expected to gradually break the iceberg apart.
The event is still expected to alter the marine environment but not as significantly as a full-blown collision, which has always been a distinct possibility.
“Nutrients stirred up by the grounding and from its melt may boost food availability for the whole regional ecosystem, including for charismatic penguins and seals. We have several ongoing studies looking at exactly how ‘megabergs’ influence the ocean circulation, its chemistry, and the ecosystems they support,” Meijers stated.
According to NOAA, the island has an extensive population of penguins, seals and birds in what is considered a milder climate compared to the extremes faced at the South Pole.
Due to the island’s location about 1,700 miles off the coast of Antarctica, the territory has had several encounters with icebergs that have caused significant disruptions to wildlife.
In 2004, an iceberg known as A-38B ran aground near the island’s continental shelf, causing extensive hardships for marine life.
Satellite animation of the world’s largest iceberg, A23a, in February, in the South Atlantic.
(NOAA)
WORLD’S LARGEST ICEBERG ON POSSIBLE COLLISION COURSE WITH ISLAND IN SOUTH ATLANTIC OCEAN
In addition to environmental impacts, researchers say the broken pieces of ice could pose significant risks to vessels, as the clumps of ice are more difficult to track.
“Discussions with fishing operators suggest that past large bergs have made some regions more or less off-limits for fishing operations for some time due to the number of smaller – yet often more dangerous – bergy bits,” Meijers stated.
While events the size of A23a are rare, Meijers said that icebergs are a normal part of the lifecycle of the globe’s ice sheets.
Complexes of ice are a growing concern as warming ocean temperatures contribute to the increased calving of ice from around the poles.
The U.S. National Ice Center constantly tracks dozens of icebergs that pose a threat to shipping routes around the waters of Antarctica, many of which are under observation by organizations such as the BAS.
Map of the giant iceberg by the Mapping and Geographic Information Centre, British Antarctic Survey.
(Mapping and Geographic Information Centre, British Antarctic Survey / FOX Weather)