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Not -PDO, but La Nina base state


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We have had an anomalous global pattern since 1998. As you can see below, the -PNA (North Pacific ridge), has recently exceed global warming and appears as an anomalous area in the Hemisphere:

https://ibb.co/2csFL89

Because we have had a N. Pacific Ocean ridge, many have identified the waters effected as "-PDO", because they are measured based on cyclical moves over long periods. However, if you look at the whole globe, you will see that the area effected in the N. Hemisphere where the Hadley Cell and Mid-latitude Cell meet is the same place as in the S. Hemisphere where the Mid-latitude Cell and Hadley Cell meet: 

https://ibb.co/yRGTTHn

Based on that, you would say forcing is not coming from a body of water in the N. Pacific ocean, but the equator, and more specifically the Nino 3.4 region where variations have been known to make big global impacts.
So in the last 25 years, I separated years by ENSO event and Neutral, and found that we are seeing a La Nina base state in both conditions:

ENSO analogs: https://ibb.co/V9yfKh2

Neutral ENSO: https://ibb.co/g7ffp52

The Hadley/mid-latitude cell meet is still there on both composites, but it expands both north and south in the Northern and Southern Hemisphere on the Neutral ENSO years.

I think that instead of identifying this period as -PDO phase, we should call it more of a La Nina phase (98-23). 

Basically, when ENSO is Neutral we are still getting an equilateral La Nina base state. 

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