A region near Cape Code and the Gulf of Maine is identified as featuring the highest North Atlantic persistence, with a unique combination of high-amplitude, persistent sea surface temperature anomalies, associated with substantial upper ocean heat content anomalies. A mechanism is advanced, whereby that region's surface ocean represents deep upper ocean dynamics, with thermal evolution that tracks heat flux divergence by the slowly adjusting subtropical gyre. This is consistent with the subtropical gyre playing a central role in NA climate variability. Successive lag correlation patterns reveal surface oscillations that are not apparent in the raw surface data. Finally, the correlation patterns are used for NAOI forecasting, using a new forecasting method that is presented and explained.
Forecasts are robust and reproducible, outperforming alternative methods.
It is suggested that the combination of skills and lead times may prove societally useful.