This is an 18 October Global Synoptic-Dynamic Model plot showing 4 weeks of information that is able to be conveyed on a single chart. It's called a phase space diagram and you'd have to watch Ed Berry explain it on YouTube.
I had the good fortune to run into this recently. (first image) It shows conditions leading to barely neutral to negative global wind
The AAM is computed by interolating forecast of the operational numerical weather model:
http://aam.earthrotation.net/rt/GIFS 1 & 2 Northern Hemisphere & Southern Hemisphere show complete polar vortex breakdown at all levels. Something is wrong.
Below that is the ECMWF at hour 240 around November 11 which is still on an 8 day cycle of the polar cell gyrating in & out as it turns atop the Earth. Once the rest of this area fills in and the winter tropospheric polar cell gets going, there are models indicating very low sea level pressure over the Arctic in DJF. Well, maybe the built up atmospheric angular momentum that is conserved in models by parameter wants to now push it forward and create a very strong zonal jet stream over the U.S. why not
I hope it works that way but about half of these waves are breaking through the jet stream in late Summer - Autumn
Anyway, a lot of the other indicators like La Nina temps off the South American West coast suggest continued negative global wind speed (Mr) as measured atmospheric angular momentum.
In that lecture linked above on this page of Ed Berry in 2018, he speaks about a risk. Atmospheric super-rotation, a condition in which tropical convection firing in the ITCZ tends to accelerate the atmosphere faster than the Earth's rotation
Ed also attests to a recent (since the 90's) trend of lower AAM, while he also asks *why* does thin sea ice lead to a negative Arctic Oscillation.
I think they lost faith in the GSDM after 2018. Just like the Madden-Julian Oscillation long-range weather indicator is increasingly stuck in Phase 8, 1, and 2
Academics aren't allowed to say this stuff, and in Ed's lecture he doesn't finish the sentence, but an atmospheric super-rotation is what most planets do. Like Venus. He may have been about to describe the differences in where waves originate on such bodies
We are at points on both of those renowned teleconnections GWO and MJO indicating low atmospheric angular momentum and seem to be stuck there
In forecast these products rely on models but they have to be watched real time, but they should outperform numerical models
well they do. the remaining polar low is in such a shape that it causes a split vortex. We see it when polar arms get spun out by tropical highs busting right through the jet stream and sticking to the North Pole until they dissipate.
Maybe a big driver of that is solar minimum. I kinda pray it. It's also super obvious that another big factor is thin Arctic sea ice.
What I don't think *anybody* expected was according disruption of the Southern polar cell.
We're right now seeing a sudden stratospheric warming following through from the stratosphere to the ground and it is predicted to final warm the winter polar vortex over Antarctica in the next few days. Meanwhile, Looks increasingly like the nascent Northern polar vortex is being split in November. This could be the earliest polar vortex sudden warming in NH winter ever. I tend to think it will slightly defy description.
what we are seeing since 2013 and especially 2016, 2018, and 2019 is atmospheric restructuring. all the processes of a stable global interglacial distribution of ground temperatures are broken. the polar vortex, jet stream, zonal mass, and geopotential height over the poles.
this is the hothouse Eocene climate waking up. how long is that supposed to take, 3-15 years?
WHY? Well, one explanation is a self-reinforcing bad feedback loop worldwide with all these fatal factors piling on at once.
Jesus, be a sun spot.