He iceberg largest and oldest in the world, A23acame off the ocean vortex that kept him trapped near the South Orkney Islandsin an archipelago of the Antarctica.
This ice colossus, with an estimated weight of almost a billion tons and a area of 3,600 square kilometersequivalent to five times the area of New York, is now at the drifts in the Southern Ocean. The satellite images analyzed by the British Antarctic Survey (BAS) confirmed the displacement.
According to scientists at the British Polar Institute, the mega iceberg, which is twice the size of Greater London, will travel to the warmer waters of the South Atlantic, where it will eventually break into smaller fragments until disappear.
In response to the query of Infobaehe doctor in geology and glaciologist Lucas Ruizassociate researcher at Conicet at the Argentine Institute of Nivology, Glaciology and Environmental Sciences (IANIGLA), explained that the visible part of the iceberg represents only 10% of its total volume, since the rest remains submerged until reaching the seabed.
In October of this year, the report Protecting a Changing Southern Oceanfrom the Antarctic and Southern Ocean Coalition (ASOC), added to the growing scientific evidence and warned about the “unprecedented anomalies” who face the Antarctica and the Southern Oceancon record temperatures, marine heat waves more frequent and a accelerated thaw. These conclusions coincided with key meetings on conservation of the planet’s resourceslike COP16 in Colombia.
A23a is a remnant of iceberg A23, which broke off in 1986 from the Filchner Ice Shelf in Antarctica.. This initial iceberg fragmented into three parts, with block A23a being the largest. For more than three decades, it remained locked on the seabed of the Weddell Sea, where its ice sheets, up to 400 meters thickresisted the attacks of time.
In 2020began its slow movement towards the north, but it was not until 2023 when it managed to free itself from the ocean vortex known as Taylor’s Column, which kept turning on itself.
“The iceberg’s journey was marked by intriguing scientific events. For months, the iceberg was trapped in a Taylor plumean oceanographic phenomenon in which water swirling over a seamount traps objects in place. “This dynamic caused A23a to rotate at one point, delaying its rapid drift towards the north,” the British Polar Institute said in a statement.
Ruiz explained that the iceberg broke off from the Antarctic shelf approximately 30 years ago and since then remained stranded in a specific area. This phenomenon occurred because, while it does not lose volume due to melting, the iceberg cannot free itself from the anchorage that keeps it stranded.
In this case, when anchored, the iceberg rotated around its grounding point, similar to what happens when a ship hits bottom in shallow waters. “This behavior is part of the natural life cycle of icebergs, which usually remain stranded for a time before being moved by subantarctic currents to more areas.” southern. Eventually, such an iceberg could get closer to South America“, he told Infobae glaciologist and Conicet researcher.
Andrew Meijersoceanographer British Antarctic Surveystated: “We are interested in seeing whether it will take the same route as other large icebergs that have broken off from Antarctica. And more importantly, what impact will this have on the local ecosystem.”
Climate change may have influenced the movement of iceberg A23a, which is in a state of deterioration obvious. Warmer temperatures, both in the air and in the surface waters of the ocean, They were wearing away at its edges, although its central part remains relatively intact, the British researchers said.
Meanwhile, Ruiz considered that more research is needed to determine if the increase in temperature caused by global warming is the cause of the breaking off of this giant iceberg, or if, in the case of A23a, it is the natural life process of the icebergs, which as they break off from the Antarctic shelf, sail towards more southern waters.
Its once colossal mass is decreasing as it moves toward warmer areas away from Antarctica, a journey that experts say will accelerate its disintegration.
This melting process, in addition to being inevitable, will have ecological and oceanographic implications.
Like other icebergs in the Weddell Sea, A23a is likely carried by the Antarctic Circumpolar Current towards the South Atlanticthrough the well-known “iceberg alley”.
Its most likely destination is the subantarctic island of South Georgia, where it will break up into smaller pieces that will eventually melt.
A year ago, a team of researchers from the British Antarctic Survey, aboard the modern research vessel RRS Sir David Attenboroughhad the opportunity to study iceberg A23a up close, during a scientific expedition in the Weddell Sea, as part of the BIOPOLE project.
During this mission, they captured the first images of the moving iceberg and collected essential data to analyze how Antarctica and sea ice ecosystems affect global carbon and nutrition cycles.
Laura Taylor, biogeochemist at BIOPOLEhighlighted the importance of this research: “We know that these gigantic icebergs can contribute nutrients to the waters through which they pass, creating thriving ecosystems in areas that would otherwise be less productive. What we don’t know is what difference particular icebergs, their climb and their origin make in this process.”
