The oceanographic tower Acqua Alta:: more than a quarter of a century of activity

This paper summarizes the relevant research activities that have been carried out on board of the oceanographic tower curing more than, quarter of a century of its active life. There is no special event that has triggered this paper, but the conviction that the amount of researches and results, still already published in the specialized magazines, deserves a summarizing and compact presentation. In this way it is possible to appreciate the frequent interaction among the different branches of the marine researches, and to realize how a single relevant result is always the final product of a large number of previous advances. Still with a predominance of the physical aspect, the paper covers many subjects of the marine research, moving from biology and chemistry to the physics of the atmosphere and the ocean. The location of the tower is in the Adriatic Sea, 15 km off the coast of the Venice lagoon. The limited depth (16 m) excludes any consideration of the deep water processes in the oceans, but provides the rare possibility of combining fundamental research and intensive practical applications of the obtained results. Expectably, the presence of Venice, prime reason for the existence of the tower, has been a catalyst in this direction.