Katsushika Hokusai, Thirty-six views of Mt. Fuji.

When strong winds blow above the sea, waves occur. This has been common sense since Hokusai, the artist who made this famous woodblock print, was around. But why? It takes a lot of effort for air to lift water which is far heavier than itself, and create great mountains of water. Why would wind go to all that trouble? It would be a lot easier to just blow across expanses of calm flat water. But in actual fact, we never see flat, calm seas in the middle of a storm. Big, crashing waves are part and parcel of storms.