Since the launch of NASA's first ocean-observing satellite, Seasat, in 1978, the Physical Oceanography Distributed Active Archive Center (PO.DAAC) has become the first data center for measurements focused on sea surface topography, ocean temperature, ocean winds, salinity, gravity, and ocean circulation. In addition to providing access to its data holdings, PO.DAAC acts as a gateway to data stored at other ocean and climate archives. This and other tools and services enable PO.DAAC to support a wide user community working in areas such as ocean and climate research, applied science and industry, natural resource management, policy making, and general public consumption. The PO.DAAC is one of the Earth Observing System Data and Information System (EOSDIS) Distributed Active Archive Centers (DAACs) that archive and distribute earth science data, managed by NASA's Earth Science Data and Information System Project (ESDIS), as part of the Earth Science Data Systems (ESDS) Program.