Scientists recently announced that a massive slab of ice nearly six times the size of New York City
has broken off an ice shelf in Antarctica
, creating the world's largest iceberg
On May 13, a researcher with the British Antarctic Survey spotted the iceberg, dubbed A-76, breaking away from the Ronne Ice Shelf in the Weddell Sea. The separation was confirmed by the US National Ice Center (USNIC) using satellite images.
According to the USNIC, the long block of ice is roughly 1,668 square miles in size, spanning 89 nautical miles on its longest axis and 14 nautical miles on its widest axis.
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The break was “not unexpected... but it did come out of the blue, sort of,” according to Christopher Readinger, the lead analyst for the USNIC’s Antarctic team.
That's because icebergs breaking off larger ice masses — or "calving," as experts call it — are generally unpredictable, and crevasses aren't always an indicator that something is about to happen, according to Readinger, who spoke to Stardia on Thursday.
“We could watch them for years and they will do nothing, while elsewhere there will be this perfectly solid ice shelf that will collapse unexpectedly,” he said.
According to NASA, ice calving, even at relatively large sizes, is not necessarily a cause for concern as long as the ice sheet is considered to be in overall balance, which occurs when the amount of ice gained through snowfall equals the amount of ice lost through melting and iceberg calving.
Like Readinger, Ted Scambos, a research glaciologist at the University of Colorado
at Boulder, told Reuters that the breaking off of A-76 is unlikely to be caused by climate change
, and that melting ice will not raise sea levels because the ice was already in the water as part of a floating ice shelf.
Readinger believes A-76 will eventually melt and disintegrate; the question is when and where this will occur.
A fragment of a once massive iceberg, B15, that calved around 20 years ago is still floating around, and another iceberg has been stuck in the same spot for the last 33 years, he said.
According to Readinger, A-76 could also travel northward, out to sea, and break apart due to waves, warming temperatures, and meltwater on the ice's surface that will percolate downward and fracture the ice.
According to the European Space
Agency, A-76 is the world's largest iceberg for the time being, displacing the A-23A iceberg, which is approximately 1,498 square miles in size and is also located in the Weddell Sea.
The icebergs in this region of the world are traditionally named after the Antarctic quadrant where they originated, with “A” representing the Weddell and Bellingshausen Seas and 76 indicating that it is the 76th iceberg tracked by USNIC in that quadrant. An iceberg is assigned a sequential letter if it breaks off from a larger named mass.
The Ronne Ice Shelf, named after Edith “Jackie” Ronne, the first American woman to visit Antarctica as part of an exploration expedition in the 1940s, is the second largest in Antarctica.