This network of floats will collect data on the chemistry and the biology of the ocean from the surface to a depth of 2,000 meters, augmenting the existing Argo array that monitors ocean temperature and salinity. Data streaming from the float array will be made freely available within a day of being collected via the Argo data system, and will be used by researchers around the world. These data will allow scientists to pursue fundamental questions concerning ocean ecosystems, observe ocean health and productivity, and monitor the elemental cycles of carbon, oxygen, and nitrogen in the ocean through all seasons of the year. Such essential data are needed to improve computer models of ocean fisheries and climate, and to monitor and forecast the effects of ocean warming and ocean acidification on sea life.