Melting Ice in Antarctica Causes Concern – Record Heat in 2025

2025 was the third warmest year on record. This is according to a new report from the EU’s climate service Copernicus. For the first time, the planet’s average temperature has been above 1.5 degrees Celsius for three consecutive years.

One of the places where this is most noticeable is Antarctica.

^{Text: Amanda Saveland}

‘There are many metres of potential sea level rise stored in that ice. So it makes it feel particularly serious that Antarctica is now also beginning to be so clearly and strongly affected by this temperature increase,’ says Erik Kjellström, professor of climatology at SMHI.

Unlike the Arctic, where researchers have seen a sharp rise in temperature over several decades, the trend has not been as clear in Antarctica. It is only in the last decade that the sea ice around the continent has begun to decline, and 2025 was a record warm year.

Last year, the average temperature in Antarctica was 1.06 degrees higher than during the period 1991-2020. Such a large deviation has never been measured before, and for most of the year, the extent of sea ice was well below average.

Vulnerable glaciers are melting

‘We know that even Antarctic ice shelves are partially sensitive to this warming, and that parts of them may begin to be increasingly affected by warm seawater in particular,’ says Erik Kjellström.
One of the most vulnerable glaciers is the so-called Doomsday Glacier, Thwaites, in West Antarctica. Previous research has shown that warm seawater has begun to penetrate beneath the glacier, which could cause the ice that currently rests on the sea floor to erode and begin to float. This, in turn, could accelerate the melting process.

‘If large parts of these sensitive ice sheets in West Antarctica were to melt, we are talking about a 4-5 metre rise in sea level. Perhaps even more. And there is a risk that this could happen in a couple of hundred years, which in this context is fast and will lead to very big problems with climate adaptation,’ says Erik Kjellström.

Warmest La Niña year on record

Another distinctive feature of 2025 was that sea surface temperatures remained historically high. The only years that were warmer were 2023 and 2024, when several heat records were broken in the world’s oceans. These temperatures were intensified by the El Niño weather phenomenon.

‘This affects sea surface temperatures, especially in the tropical Pacific Ocean. And we are talking about such large areas of ocean that the deviation is actually most often seen in the global average temperature,’ explains Erik Kjellström.

The high sea surface temperatures over the Pacific Ocean can raise the global average temperature by a tenth of a degree, sometimes more, and were severe in 2023 and 2024. But last year, the opposite weather condition, La Niña, prevailed.
“Then it’s the opposite. It is colder than average in large areas of the eastern Pacific Ocean, says Erik Kjellström.

Despite this, last year was the third warmest on record.

And it is also a clear sign that it is getting warmer. That even during a La Niña year, we still have a very high global average temperature.

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