- There were 2.2 million square kilometers less ice than usual during the winter of 2023
- These low levels would be an event that occurs every 2000 years without climate change
Experts have said record sea ice levels around Antarctica in 2023 may have been caused by climate change.
Last year there was 2.2 million square kilometers less ice than usual during the winter around Antarctica, which is about 10 times the size of the United Kingdom.
To find out why it happened, researchers from the British Antarctic Survey (BAS) analyzed data from 18 different climate models.
They found that Antarctica’s historically low sea ice levels were a once-in-2,000-year event without climate change, but four times more likely under its effects.
Rachel Diamond, lead author of the paper, said: “This is the first time this large ensemble of climate models has been used to find out how unlikely the decline in sea ice in 2023 really was.”
Record sea ice levels around Antarctica in 2023 may have been caused by climate change, experts say
Last year there was 2.2 million square kilometers less ice than usual during the winter around Antarctica, which is about 10 times the size of the United Kingdom.
‘We only have 45 years of satellite measurements of sea ice, which makes it extremely difficult to assess changes in sea ice extent.
«This is where climate models become important.
“According to the models, without climate change, an unprecedented minimum extent of sea ice would be a phenomenon that would occur every 2,000 years.
“This tells us that the event was very extreme: anything less than one in 100 is considered exceptionally unlikely.”
Antarctica’s vast expanse of sea ice regulates Earth’s temperature, as the white surface reflects heat from the Sun back into the atmosphere and cools the water beneath it.
Without it, the planet would be a much hotter place.
For the study, the team used the latest climate data set called CMIP6 to investigate whether warming influenced Antarctic sea levels.
For the study, the team used the latest climate data set called CMIP6 to investigate whether warming influenced Antarctic sea levels.
Antarctica’s vast expanse of sea ice regulates Earth’s temperature, as the white surface reflects heat from the Sun back into the atmosphere and cools the water beneath it.
Caroline Holmes, co-author of the study, said: “The strong climate change (i.e. the temperature changes we are already seeing and those expected if emissions continue to rise rapidly) in the models makes it four times more likely to see such a large decrease in sea ice extent.
“This suggests that the extreme low in 2023 was due to climate change.”
BAS scientists also looked at how likely sea ice is to recover and found that it would remain low, even after 20 years.
This would affect penguins, whales and other animals that depend on ice for habitat, the researchers said.
Louise Sime, co-author of the study, said: “The impacts of Antarctic sea ice remaining low for more than 20 years would be profound, including on local and global climate and on unique ecosystems in the Southern Ocean, including whales and whales. penguins”.
The formation of sea ice around Antarctica acts as a driver of ocean currents and influences weather patterns.
It also protects the exposed edges of ice shelves from waves, slowing Antarctica’s contribution to sea level rise.
Until 2015, Antarctica’s winter sea ice had been growing in size since satellite records began in 1978.
The findings were published in the journal Geophysical Research Letters.
