What are the effects of combo swells for surf? How do swells of diffenent periods or directions interact when they hit the shore? Are there more favorable period, height, or direction combinations? Swellinfo I'm thinking you may have some thoughts on this.
swells have 3 dimension. height, period, direction.
The other crucial variable(s) is the ocean bottom configuration (which way the coastline is facing, and the slope of ocean bottom).
Changing any one of the variables above will change how a swell behaves for a particular break.
As far as combo swells in the water at the same time... In the deep, open ocean waters, the swells act more or less independent of each other (not much interaction between the swells). But as the combo swells hit the beach, they can affect the breaking wave. Its kind of hard to quantify, but a lot of times a combo swell will create peaky waves. Not as long of lines, but more sectiony waves. This can be bad or good depending on the break.