An acqua alta (/ˌækwə ˈæltə/,[1] Italian: [ˈakkwa ˈalta] ; lit. 'high water') is an exceptional tide peak that occurs periodically in the northern Adriatic Sea. The term is applied to such tides in the Italian region of Veneto. The peaks reach their maximum in the Venetian Lagoon, where they cause partial flooding of Venice and Chioggia; flooding also occurs elsewhere around the northern Adriatic, for instance at Grado and Trieste, but much less often and to a lesser degree.
The phenomenon occurs mainly between autumn and spring, when the astronomical tides are reinforced by the prevailing seasonal winds that hamper the usual reflux. The main winds involved are the sirocco, which blows northbound along the Adriatic Sea, and the bora, which has a specific local effect due to the shape and location of the Venetian Lagoon.
- ^ "acqua alta"[dead link] (US) and "acqua alta". Lexico UK English Dictionary. Oxford University Press. Archived from the original on 2020-03-22.