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https://www.theguardian.com/environment/2025/sep/26/fears-of-abnormally-hot-days-in-southern-australia-after-sudden-stratospheric-warming-over-antarctica>
"A rare rise in stratospheric temperatures over Antarctica could influence
weather into summer, with previous events driving hotter and drier conditions
for south-east Australia.
The phenomenon – called sudden stratospheric warming – is extremely unusual in
the southern hemisphere.
There have only been three moderate to major events in the past 45 years – in
1988, 2002 and 2019 – a Bureau of Meteorology spokesperson said, with the
latter contributing to a worsening of the black summer bushfires.
In early September this year, air temperatures 30km above the Southern Ocean
and Antarctica began to climb, and are now sitting about 30C warmer than
average, according to Dr Martin Jucker, a senior lecturer in atmospheric
science at the University of New South Wales.
“Normally it’s about minus 50C, so now it’s minus 20C – it’s still pretty
cold,” Jucker said.
The warming is accompanied by a slowdown in the powerful winds above the
Earth’s polar regions, called the polar vortex. Usually those winds are about
200km/h but are now about 100km/h.
Those changes are likely to drive warmer and drier weather patterns at the
surface, particularly in NSW and Victoria. But the effects this time around are
partly unknown, given the Bureau of Meteorology’s forecast for wetter
conditions.
“So there is a balancing act between these very warm ocean temperatures, which
would drive wet weather for us, versus the stratosphere, which would drive dry
weather,” Jucker said. “Who wins? I don’t know.”"
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
