English: (a,b) Leading two EOF modes of model composite simulated SLP anomaly variability in the North Pacific (shading, hPa). EOF1 (a) projects on the Aleutian Low and EOF2 (b) has a structure associated with the North Pacific Oscillation (NPO). (c) North Pacific simulated SLP anomaly regression pattern (shading, hPa) for the full (non-composite) model normalized CP ENSO SST anomaly forcing time series. (d) Leading North Pacific SST anomaly EOF (shading, °C) for the full model simulation. (e) Corresponding normalized PC1 (black) and the 8 years low-pass filtered PC1 (red). (f) MTM power spectrum (no unit) for the normalized PC1. The dashed line indicates the 99% confidence interval for an AR(1) null hypothesis. The forcing frequency (f E ) and the first-order combination tones (1 ± f E ) are labeled. The maps in this figure were created using NCAR Command Language Version 6.4.0 (https://doi.org/10.5065/D6WD3XH5).