Study finds ‘direct evidence’ of polar amplification on continent as scientists warn of implications of ice loss

Antarctica is likely warming at almost twice the rate of the rest of the world and faster than climate change models are predicting, with potentially far-reaching implications for global sea level rise, according to a scientific study.

Scientists analysed 78 Antarctic ice cores to recreate temperatures going back 1,000 years and found the warming across the continent was outside what could be expected from natural swings.

In West Antarctica, a region considered particularly vulnerable to warming with an ice sheet that could push up global sea levels by several metres if it collapsed, the study found warming at twice the rate suggested by climate models.

Climate scientists have long expected that polar regions would warm faster than the rest of the planet – a phenomenon known as polar amplification – and this has been seen in the Arctic.

Dr Mathieu Casado, of the Laboratoire des Science du Climat et de l’Environnement in France and lead author of the study, said they had found “direct evidence” that Antarctica was also now undergoing polar amplification.

“It is extremely concerning to see such significant warming in Antarctica, beyond natural variability,” he said.

Antarctica is the size of the continental US and Mexico combined, but has only 23 permanent weather stations and only three of these are away from the coast.

Casado and colleagues examined 78 Antarctic ice cores that hold a record of temperature and then compared those temperatures to climate models and observations.

The research, published in the journal Nature Climate Change, found Antarctica was warming at a rate of between 0.22C and 0.32C per decade, compared to 0.18C per decade predicted by climate models.

Part of the warming in Antarctica is likely being masked by a change in a pattern of winds – also thought to be linked to global heating and the loss of ozone over the continent – that has tended to reduce temperatures.

Dr Sarah Jackson, an ice core expert at the Australian National University, who was not involved in the study, said the findings were “deeply concerning”.

“All our projections for future sea level rise use these low rates of warming. Our models might be underestimating the loss of ice that we might get,” she said.

Dr Danielle Udy, a climate scientist and ice core expert at the University of Tasmania, who was not involved in the paper, said the research was timely “given the extreme events we have been seeing in Antarctica”.

Scientists are scrambling to understand why Antarctic sea ice has been at record low levels over the last two years, with some suggesting global heating could now be affecting the region.

Thousands of emperor penguin chicks likely died in late 2022 after the usually stable sea ice supporting colonies in West Antarctica melted.

Dr Kyle Clem, a scientist at Victoria University of Wellington in New Zealand, has studied recent record high temperatures at one weather station at the south pole.

Clem said Antarctica’s climate was subject to large natural swings, but Casado’s study had shown “a detectable change in Antarctic climate and an emergence of anthropogenic polar amplification”.

He said the results would be crucial for understanding the future of the continent “as greenhouse gases continue to increase”.

“The implications of this study are of particular importance for considering future changes in Antarctic sea ice, terrestrial and marine ecosystems, and potentially even sea level rise,” Clem said.

“If anthropogenic polar amplification is already occurring in the Antarctic that exceeds that simulated by climate models, then future warming will likely be greater than that currently projected by climate models.”

A warming Antarctic, he said, would also likely lead to further losses of sea ice that would have implications for “ocean warming, global ocean circulation, and marine ecosystems”.

“As far as sea level rise, ocean warming is already melting protective ice shelves in West Antarctica and causing the West Antarctic ice sheet to retreat.”

Greater warming could also lead to more melting of coastal ice shelves that protect glaciers.

“This has already been seen on the Antarctic peninsula in recent decades, and it could become a more widespread occurrence around Antarctica sooner than anticipated in a more strongly warming Antarctic climate,” he said.


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  • @kicksystem@lemmy.world
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    31 year ago

    I’m old enough to remember the pre-internet age in detail and I thoroughly disagree. I am sure there have been studies on this topic, but I’ll defer to my own experience for now.

    Before the internet everybody got their information via the same set of channels, TV, radio, news papers. If you really wanted to know something you had to go to the library to usuaully get disappointed. People were much less likely to disagree with you back then, because most people got their information from the same set of sources. Nowadays you’ve got such an explosion of opinions on basically everything. You might meet a pro-life, climate change denying flat earther one day and meet an non binary vegan activist the next. People are much harder to control now and governments are taking longer and longer to try and please anyone, which anyway fails pretty much every time too.

    Sure there are still plenty of places on the internet that brainwash whole populations with information bubbles, but the fact that there are so many more sources of information makes it so much harder to catch large crowds.

    I am guessing you might be American, because that is one place where the brainwash of republics vs democrats is still working pretty well. From my European vantage point its mostly the republicans that are still very much in control of the minds of their voters.

    • @emptiestplace@lemmy.ml
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      11 year ago

      We are biologically predisposed to selfishness. You can frame this with political colors that ostensibly represent “thoughtful and empathetic” versus “thoughtless and ‘fuck you, I’ve got mine’”, but it’s not entirely clear that either side isn’t inherently motivated by selfishness. And that’s our ultimate failing, predictor of our demise.

      Regarding diversity trends, I agree. Thank you for reminding me how it was. I do worry though: is counter-culture as popular culture counterproductive? Could that be by design?

      Not American.

      • @kicksystem@lemmy.world
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        01 year ago

        but it’s not entirely clear that either side isn’t inherently motivated by selfishness

        That could also be explained by us just not being entirely pre-disposed to be selfish. At least some part of us has evolved to be a social and empathetic, which forever pushes us to be altruistic and moralistic. History is full of stories of the brave, unselfish and compassionate. Plenty of people have died for causes they truly believe in. It also seems we’re never done evolving our ethics and that makes sense, since we’re brainy herd animals.

        It also seems to me that evolution likes game theory and that therefore the angelic side and the dark side of our human souls are forever locked in battle. The good news is that when there are enough resources to go around, societies can become quite nice to live in. The bad news is on the other hand is that when those sea levels indeed will rise we’ll be back to killing each other quite quickly.

        is counter-culture as popular culture counterproductive?

        Counter culture becomes popular and then it is not counter culture anymore. This cycle repeats itself endlessly. I remember the gabber scene of the 90s that very much started as a counter culture, but then became mainstream through commercial success. The oldskool gabbers hated that, but after a few years the commercial success died off and it slowly evolved and re-emerged as a new counter culture. I don’t think it is by design, but it is just that social dynamics are just most predictable than we tend to think.

        It seems to me though that through the diversification of culture, which I would ascribe in large part to the internet, counter culture movements have a lot less steam to them. Before the internet people (but mostly youngsters) could pick from a handful of sub-cultures to be part of: rocker, skater, punker, alto, hippie, goth, gabber, raver. Those movements were large and powerful. Now there are uncountably many sub-cultures, so counter culture isn’t such a force to be reckoned with either. No more parents on radio talk shows who are concerned that their children may be possessed by the devil.

        Just found this:

        Throughout the mid to late 2010s, subcultures splintered and merged due to the widespread accessibility of the internet and social media platforms. Many 2010s subcultures drew from previously existing groups - the popular ‘e-girl’ subculture is seen as a modern spin on mid-2000s scene fashion.[7] As part of their retrospective series on the 2010s, Dazed magazine described the impact of technology on subcultures; “But [the internet] also gave us more; it gave us dozens upon dozens of scenes and movements, only recognisable to the highly trained eye. And the rules became less rigid: you could dress one way, and listen to totally different music.”

        This echoes my point.