Global Sea Ice Extent Hits All-Time Low Record
According to satellite data, the worlds frozen oceans currently have less ice than ever before recorded. The sea-ice around the north and south poles serves as a giant mirror, reflecting much of the Sun’s energy back into space.
However, rising temperatures are causing this bright layer to shrink. As a result, the dark ocean below absorbs more heat, leading to further warming of the planet.
The latest sea-ice low appears to be driven by warm air, warm seas and winds breaking apart the ice. Over five days from February 8th to 13th, the combined extent of Arctic and Antarctic sea-ice was recorded at 15.76 million sq km (6.08 million sq miles), according to BBC analysis.
This breaks the previous record low of 15.93 million sq km (6.15 million sq miles) from January-February 2023, reported by Walter Meier, a senior research scientist at NSIDC.
Arctic sea-ice is currently at its smallest recorded extent for the time of year, while Antarctic sea-ice is close to a new low in satellite records going back to the late 1970s. The decline of Arctic sea ice in response to a warming planet has been well-established.
Its end-of-summer extent fell from an average of 7 million sq km in the 1980s down to around 4.5 million sq km in the 2010s, according to recent studies. Until then, Antarctic sea ice had been remarkably resilient, defying predictions that it would shrink.
However, since mid-2016 Antarctica has shown a series of very low sea-ice extents despite significant natural variability.
“Every year every data point we get suggests that this isnt a temporary shift but something more permanent like what we’ve seen in the Arctic,” says Walter Meier. “It is indicating that the Antarctic has moved into a new regime with lower ice extent.”
Antarctic sea-ice is relatively thin and mobile, surrounded by ocean rather than continents, so it can be particularly sensitive to winds breaking up the ice.
However, warmer air and water look set to play key roles in this latest 2025 low. Towards the end of the southern hemisphere summer, Antarcticas record sea-ice low from 2023 would have been a one-in-two thousand year event without climate change, according to recent studies.
Yet 2025 is not far from eclipsing it. At the other end of the planet, Arctic should be reaching its annual maximum with cold winter temperatures helping the oceans freeze over. But current sea-ice extent is nearly 0.2 million sq km below anything previously recorded for that time.
This partly as a result of a late freeze-up in ice around Hudson Bay, where unusually warm ocean waters take longer to cool down. Apart from warmer seas some storms also disrupted the ice in Barents and Bering Seas with long-term reductions in sea-ice thickness amplifying the consequences.
