I noticed that. If he were arguing the PMM influences the pattern (subtropical/near-equatorial component of cold SSTA horseshoe) I would be inclined to agree.
But the high latitude SSTAs are basically an echo of the low frequency state of circulation. They do not act as a forcing (at least not on any timescale relevant to us, there’s some debate when looking at 500+ year timescales).
Posted by Bryant,
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