In order to apply CV, I have processed wind and wave data for the Arabian Gulf where WWIII data is not available. To simplify the process, I selected only two points near my AOI. When I ran the model I noticed in the log that wind and wave data is interpolated to each shore point (which was not clear in the user guide). I would like to know more about the interpolation step. My questions are:

How many wind/wave data points does the model use for interpolation and/or what is the threshold distance?

How many wind/wave data points are necessary to inform the model?

Can I assume that providing the nearest data points in each direction will be sufficient?

The model finds the nearest three WWIII points to each shore point. It only searches within 3degrees (or 210km) around the shore point. It uses the distance from the shore point to each of the three WWIII points in order to create a weighted average of the WWIII values to assign to the shore point. That is the interpolation method.

The model will run successfully as long as each shore point has at least one WWIII point within the 3 degree or 210km search radius, but it will use up to three points if available.

Yes, this should be sufficient. Technically the model will work with only one WWIII point in proximity to the shore, but better estimates could come from having WWIII points in different directions. Probably it is up to you to decide if more points are necessary to capture the variability in conditions in your study area.