UKH

https://twitter.com/PGDynes/status/1739942012084748734 Oh dear... are there any meteorologists out there that can verify this? Is there any precedence for this or is it entirely new? It's certainly dramatic! I'm wondering if I'm either down a "rabbit hole" or that the climate is irredeemably fubared and like the satirical film film Don't Look Up, the established media have their collective heads in the sand, because I haven't seen record sea surface temperature rises and the breakdown of the Jetstream on any mainstream news sites and if they have been, it's just been the odd incidental piece.

Twitter is weird. Under that link I see reams of abusive comments about how climate change doesn’t exist, and then at the bottom a button saying “show additional comments including abusive language”. I clicked that button out of interest and I got shown a single additional comment; a polite response acknowledging that it’s potentially a worrying observation. 

Welcome to the Anthropocene.

Agreed, the conduct of folk on twitter/X is even more depressing than the forthcoming weather-apocalypse! What hope is there... 

Not sure I like it....

Obviously humans are destroying the earth, but I wouldn't look for updates on this from a random isolated source on Twitter...

I don't think there's anything particularly new or controversial about this, as I understand it the weakening of the polar jetstream was a predicted impact of climate change and has been going on for a while.

The jet stream and polar vortex often do stuff in the northern hemispheric winter.  This looks like that and perhaps a precursor to a split polar vortex and potentially a cold spell.

Thats been happening for a long time so it looks like some tit on twitter amping up stuff beyond reason.

But them I’m not a climate expert so you shouldn’t listen to me any more than a random Twitter person.

It's useful when talking about climate periods to specify what you mean by a "cold spell" and a "long time." A cold spell could mean anything between Stalingrad and an ice age, whereas a long time for some might be decades and others millenia.

Me neither but I do listen to those who are rather than those who have opinions on it (last comment not directed at you).

True Tue. He just seems to be talking about SSW and a split vortex which means - if we land on the right side of the bent jet stream - a few cold weeks (most likely) to a repeat of winter 2010/11 (sadly unlikely).  That it’s happening is not a climate issue, the frequency with which they occur could be?

Is this the right time to watch "The day after tomorrow" again?

It’s still only happening in the minds of the forecasts for now.  If the right side of the red line on this plot rockets up above -10C I’ll dig out my BluRay of the movie….  https://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/01mb9065.pn... - even then at that point it’s 50/50 pot luck if we get warm or cold air a couple of weeks later.

I note the tweet the OP posted now has debunking “community notes” which are quite similar to what I had to say.  The plonker is hyping up normal stuff to push a climate change agenda.  They have had at least one other post similarly called out in the past.  What a plonker - the reality is so stark there’s no need to make stuff up.  Hard to tell if they’re a zealous warrior without a clue or if they’re trying to make false predictions to give the opponents of climate change fuel for their dumpster fire.

Twitter Community Notes: this animation shows, are a natural phenomenon which have occurred in about 50% of Arctic winters since the 1950s. It's also unclear how the frequency or strength of the stratospheric polar vortex might change due to climate change.

Edit: On Twitter, the author of the post lists themselves as CSO (Chef Scientific Officer) of MEER, a US based non-profit claiming they can lower global temperatures by 1-2°C by installing surface reflectors.  You'd expect the CSO of an organisation to be scientifically literate and not mis-representing a common event as a harbinger of doom, rather I'd expect them to do a rational analysis of the frequency and intensity of these events to see if that is changing.  Poor form.  He's just gone "here's a fancy visualisation - we're all doomed" but it's all noise and no signal.

Then again, I doubt the possibility that installing mirrors on buildings is going to make a meaningful change to global temperatures given the immensity of the challenge to roll it out to enough of the existing roof area to make a difference to global albedo - although it clearly can lower local temperatures enough to make a difference to comfort and survivability and that's an important thing to follow.  I think deliberate geo engineering with e.g. sulphur dioxide or sea spray are much less infrastructure and maintenance intensive ways of making a global difference.  

(I'm a massive fan of the potential of passive sub-ambient cooling using the cold sky - especially at night, Last summer I built a system for our house cooling air against a clear night sky that got a COP of about 15-20 on clear nights - but all those fans, insulators and mirror surfaces don't havre the scalability needed to impact global temperatures.  Spraying sea water into the air does.)

Would that mean Kinder Downfall would be in?

More on the jet stream shifting in New Scientist from 2021

https://www.newscientist.com/article/2289897-shifting-jet-stream-due-to-war...

"Direct observations of this polar jet stream only began a few decades ago thanks to the proliferation of weather satellites, says Osman, so it hasn’t been clear how global warming is affecting it.

Now he and his team have worked out how the average position and intensity of the jet stream over the North Atlantic has changed over the past 1250 years by analysing Greenland ice cores. The position of the jet stream determines storm tracks over the North Atlantic, which in turn determines the temperature of Greenland and how much snow falls there.

The results show that the position and intensity of the jet stream naturally vary a lot. “It seems to be fairly random,” says Osman. Because there is so much variability, global warming hasn’t yet had a discernible effect. The situation is like being on a beach when the tide turns – if the waves are big, it takes time before the rising tide is obvious."

It goes on to say:

"But climate models forecast that the jet stream will shift north as the world warms and the temperature gradient between the Arctic and lower latitudes weakens. Osman’s findings suggest that this effect will start to become obvious from around 2060. By 2100, the average position of the jet stream could be 1 to 3 degrees further north in high-emissions scenarios."

Ultimately, they say, this could lead to drier weather in southern Europe and wetter weather to the north

NOAA also have a nice article on this

https://www.climate.gov/news-features/understanding-climate/understanding-a...

One headline from the article “No clear trend but limited data”. 

It’s a fascinating area and one without much clarity.  There’ve been suggestions of a link to the solar cycle and solar activity but I’m not sure how credible they are?

Very interesting

Most likely but it might be so deeply covered that it becomes a simple snow slope.

Been a gap in the data but it’s back and hoo-wee that polar stratospheric temperature is indeed experiencing a sudden warming… https://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/01mb9065.pn...

So, 2 weeks from now might be interesting.  A lot of divergence in the models at that point but a general cold trend perhaps.  Maybe it’s time to get your copy of the training materials out and on stand-by just in case…

I’m wondering how the local farmer would feel about opening one of the giant lakes on a crop field up for ice skating….

Edit: it looks like the Tweet the OP linked to has been deleted, I guess the thread didn’t go the way the author wanted!  

Discussion about this has been rattling around for about a decade. You don't actually want a meteorologist at all, you want someone from the International Commision of Stratigraphy (ICS), or International Union of Geological Sciences, who decide on such things. The current stage of the process is that it has broadly been accepted that we need anew geological epoch due to the large-scale influxes of humans on the planet (note this is way above just climate change). The current proposal in the geologic record is one of the nuclear testing isotopes. 

not yet