GFDL_2_1 control run1 (smoothed with 5-y running mean): No stadium-wave signature. (a) Two plots are given. The first is the M-SSA spectrum for this model. Modes 1&2 fall outside the red-noise envelope. Their error bars overlap and they are somewhat separated from the remaining modes. The second plot in (a) shows the cumulative variance accounted for by the first twenty modes. (b) Shows the RCs for this model. Most modes display high frequency variability. Mode one reflects a multidecadal character, but mode two is of a different, much higher frequency. No oscillatory or propagating signal can be identified.