Sorry, there's no good way to turn off the animation.

(There is a bad way, if you mean the stripes indicating force of wind on the sails. If you turn off "sail occlusion" in the physics menu, the stripes will stop updating. They will not disappear, but they will stop moving with the ship, so you can sail away from them. But turning this off stops the sails from screening each other, so you could e.g. have full force on all square sails even right before the wind.)

You can effectively pause by turning the physics simulation rate right down.