Oceanography is in large part an observational science. Physical oceanography in particular clearly shares with the rest of fluid dynamics a deep symbiosis of theory with observation. The governing equations of motion, while known, contain so many diverse balances and resulting phenomena that observation is required to guide theory. Thus, oceanography is replete with phenomena that could have been predicted but which were discussed dynamically only after they were observed (one thinks of microstructure, the equatorial undercurrents and the Gulf Stream recirculation). Or, even had they been predicted, it is quite likely that no theory would have been taken seriously in the absence of clear observational evidence (I am trying to forestall letters pointing out that an obscure 19th century paper predicted microstructure).