A colossal iceberg ranked among the oldest and largest ever recorded is crumbling apart in warm Antarctic waters, and could disappear within weeks.<\/p>\n
Earlier this year the “megaberg” \u2014 named A23a \u2014 weighed nearly 1 trillion tonnes and was more than twice the size of Greater London, a behemoth unrivalled at the time.<\/p>\n
In recent weeks, enormous chunks \u2014 some 400 square kilometres in their own right \u2014 have broken off.<\/p>\n
Smaller chips, many still large enough to threaten ships, have also split, littering the sea around it.<\/p>\n
The iceberg is now 1,770 square kilometres, less than half its original size.<\/p>\n
“It’s basically rotting underneath. The water is way too warm for it to maintain. It’s constantly melting,” Andrew Meijers, a physical oceanographer from the British Antarctic Survey said.<\/p>\n
“I expect that to continue in the coming weeks, and expect it won’t be really identifiable within a few weeks.”<\/p>\n
Icebergs breaking up are a risk for shipping\u00a0<\/p>\n
Very large icebergs like A23a can be monitored by satellites, but once they break up into smaller ones they become difficult to track, making them a navigational hazard for ships, Jan Lieser, a marine glaciologist working with the Australian Antarctic Program, explained.<\/p>\n
“RMS Titanic is probably the most prominent example of what can happen even though she was travelling through the North Atlantic at the time, the same principle applies” Dr Lieser said.<\/p>\n
The iceberg has recently drifted away from Antarctica<\/p>\n
A23a calved from the Antarctic shelf in 1986 but quickly grounded in the Weddell Sea, north-west of Antarctica, remaining stuck on the ocean floor for over 30 years.<\/p>\n
It finally escaped in 2020 and, like other giants before it, was carried along “iceberg alley” into the South Atlantic Ocean by the powerful Antarctic Circumpolar Current.<\/p>\n
Around March, it became stuck in shallow waters off South Georgia island, raising fears it could disrupt large colonies of adult penguins and seals there from feeding their young.<\/p>\n
But it dislodged in late May, and moved on, swinging around the island and tracking north.<\/p>\n
In recent weeks the iceberg has picked up speed, sometimes travelling up to 20 kilometres in a single day.<\/p>\n
Exposed to increasingly warmer waters, and buffeted by huge waves, A23a has rapidly disintegrated.<\/p>\n
Scientists expect it won’t survive the summer<\/p>\n
As the iceberg moves further north and the Antarctic spring begins, scientists predict A23a will rapidly fall apart into chunks too small to track.<\/p>\n
“I expect its fracturing will accelerate,” Dr Meijers said.<\/p>\n
<\/p>\n
NASA photographed the A23a iceberg with satellites in January 2025 as it drifted away from Antarctica. (AFP: NASA)<\/p>\n
University of Colorado ice scientist Ted Scambos said the iceberg could even fall apart in a single day and said its collapse would look “sort of like an avalanche that’s floating”.<\/p>\n
Dr Meijers explained icebergs are “doomed” once they leave the freezing protection of Antarctica.<\/p>\n
Iceberg calving is a natural process. But scientists say the rate at which they were being lost from Antarctica is increasing, probably because of human-induced climate change.<\/p>\n
AFP\/AP<\/p>\n","protected":false},"excerpt":{"rendered":"A colossal iceberg ranked among the oldest and largest ever recorded is crumbling apart in warm Antarctic waters,…\n","protected":false},"author":2,"featured_media":127793,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[89310,6391,64,63,75,89309,89311,128],"class_list":{"0":"post-127792","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-environment","8":"tag-a23a","9":"tag-antarctica","10":"tag-au","11":"tag-australia","12":"tag-environment","13":"tag-megaberg","14":"tag-melting","15":"tag-science"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/127792","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=127792"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/127792\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/127793"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=127792"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=127792"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=127792"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}