Error with Two-Way Nesting and Different Wind Input Data in ww3_multi

[AlexCrls]

Hi everyone,

I'm using WaveWatch III in multi-grid mode (ww3_multi), with a parent grid at 9 km and a nested grid at 3 km resolution.
Both grids use wind data from the same WRF run, but:

• The 9 km grid uses the 9 km WRF wind,
  

• The 3 km grid uses the 3 km WRF wind.
  

I'm observing two main issues in the results:

1. The parent grid clearly shows the outline of the nested grid, as if the nested domain were “burned into” the parent’s results (as shown in the figure on the right).
2. The nested grid seems to reflect a transition from the parent grid, instead of using its own wind cleanly (as illustrated in the figure on the left).

Has anyone experienced a similar problem?

Should all grids use the same wind field in ww3_multi to avoid inconsistencies? If not, what is needed to ensure the simulation is correct when different grids have different wind fields? Specifically, what should be done to handle the transition between parent and nested grids to prevent errors in the simulation?

Any help or experience would be greatly appreciated!

Best Regards

Alejandro