The MJO signal in the NCEP Global Ensemble Forecast System
One critical aspect sought in the comparison of configurations is to determine the level at which MJO signal is captured and how the signal is propagated through the extratropics via teleconnections. In the benchmark experiments, a strong relationship between the prediction skill of extratropical flow and the MJO signal is found, with high skills during periods of strong MJO signal. This suggests that the atmospheric model adequately responds to forcing in the tropical Pacific. Prediction skill of main variables near the surface tend to decay fast beyond one week but upper level variables have useful skills beyond two weeks. Results of the second and third configuration indicate small changes in the flow in the extratropics but the bias of low-level and surface tropical variables is reduced. This talk will present diagnostics and skill assessments of the comparison.