In the “Unprecedented Jet Stream Crosses Equator”-video Beckwith identified three cros-equatorial jet streams that were assumed new behavior. It was explained as a redistribution of the jet streams because of climate change. One of these crossings was situated over the Pacific, one over Africa and one over Asia. While debunking his critics in a later video, he apparently dismissed two of them as related to the monsoon (the crossings over Africa and Asia). This was the subject of previous post. This post will be about the third crossing that was described as new behavior.
When looking at the ““Unprecedented Jet Stream Crosses Equator” video, I recognize the area he was focusing on: it was in the Pacific Ocean between South-America and East-Asia. An area quite known by those who look into climate data. This became pretty clear when he showed the sea surface temperatures at 04:29:
This is how it is explained:
The green circle is where the jet stream is coming down and crossing the equator. It is interesting to know that this area of water, because of the El Niño, the strong El Niño, has passed, we now getting cooling of that water as we head towards an La Niña. So this cooling of the water is lowering that pressure ridge, that high pressure ridge, that is normally at the equator and the water is anomalously hot here. That brings up the pressure up here and here. It is lowering the ridge if you like. And I think this may be contributing of allowing air to cross the equator here in the jet streams.
If we are looking at the temperature, this is the ocean water temperature, You can see that here [at the circle] it is about 24.5 degrees, if we go here [above the circle] it is about 30 and if we go down here [below that] it is approaching 30. So we got a pocket of the colder region at the equator. So this lowers the barrier which normally stops from transversing from one hemisphere to the other.
I can follow his reasoning and it might well be true, but as far as I know, this La Niña is a natural process (following a very strong El Niño). If it was the cooling from this La Niña that contributes to the “equatorial barrier” going down and making it easier for the jet stream to cross the equator, then he identified a crossing that is following a not that frequent, natural event.