the tropical atmosphere ocean (tao) project is a major international effort that instrumented the entire tropical pacific ocean with approximately 70 deep ocean moorings. the development of the tao array in 1985 was motivated by the 1982-1983 el niño event and ultimately designed for the study of year-to-year climate variations related to el niño and the southern oscillation (enso). led by the tao project office of the pacific marine environmental laboratory (pmel), the full array of 70 moorings was completed in 1994.