 Several distinct water masses converge in the immediate vicinity of the APF or Antarctic Convergence (in particular the Subantarctic Surface Water (Subantarctic Mode Water or SAMW), Antarctic Surface Water, and the Antarctic Intermediate Water).This convergence creates a unique environment, noted for its very high marine productivity, especially for Antarctic krill.Because of this, all lands and waters situated south of the Antarctic Convergence are considered to belong to the Antarctic from a climatological, biological and hydrological standpoint.