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Data from the US National Snow and Ice Data Center (NSIDC) has revealed another summer of exceptionally low sea-ice extent around Antarctica.
It’s the third year in a row Antarctic sea-ice extent has dropped below the long-term summer average of 2–4 million square kilometres, since satellite records began in 1979.
February 2023 holds the record for the lowest summer sea-ice extent over the past 46 years, of 1.77 million square kilometres – 36% less than average.
Winter sea-ice extent has also been declining.
In September 2023, it dipped to a new record low of 16.96 million square kilometres, compared to the usual 19–20 million square kilometres.
Then in the spring of 2016, Antarctic sea ice fell to a (then) record low, and has been below average for most years since.
Research points to ocean warming as playing a key role in the deficit1 of sea ice around Antarctica since then. Scientists say Antarctic sea ice may have been pushed to new state of diminished coverage2 (similar to that in the Arctic), from which it may not recover.
Antarctic sea ice has been described as the beating heart of the planet, as it expands in winter and contracts in summer.
This regular cycle of freezing and thawing3 keeps our planet functioning, regulating global climate and sea-level rise.