wave slope

Good morning, considering that the shake effect on the boat depends on the slope of the wave and not on the height; Is it possible to insert a map with the slope of the waves in cm/s?

Hi @gsplrd thank you for this suggestion, however, it is not that easy to implement completely new layer and this is not in actual plans, so I will forward this to colleagues for consideration and I would appreciate your patience and understanding.

@gsplrd
Hi, could you explain how you can express the average slope of waves in cm/s (centimeters per second). This unit seems more suiting a speed quantity. 
height/period
These two waves have the same height but the one with the shorter period has a greater slope and a greater shaker effect, 0.528 cm/s against 0.336 cm/s

@gsplrd
The wave steepness is the ratio of wave height H (m) to the wavelength λ (m).
Near the seashore it varies with the bottom depth. 
I'm talking about a very simple thing, a map of the ratio between the height / period in cm / s, are data that you already have