Why do waves get “choppy” when it is windy outside (a lot of consecutive choppy-whitewash waves)?
The wind pushes on wave crests. If the wind is relatively weak, it may add or subtract energy from the wave by doing work or negative work on it. But if the wind is too strong, it can blow the top off a crest. Choppy seas occur when the wind is so strong that it blows the surface water right out of wave crests and turns them white with foam.