During the 1970’s another effort known as GEOSECS (Geochemical Ocean Sections Study) also took measurements in all three of the major ocean basins. This time they followed tracks that led from north to south (and vice versa) rather than along lines of latitude as done during the IGY. They took observations in fewer places, but took measurements of many more different water characteristics including tracers such as the radiocarbon that had entered the ocean a decade earlier during nuclear weapons testing.
During the 1990s, after more than ten years of preparation, the World Ocean Circulation Experiment (WOCE ) undertook to measure the entire global ocean using predetermined levels of accuracy and precision to create a “synoptic” data set of physical observations to estimate the mean ocean circulation and meridional ocean heat transport. Not long after WOCE began it was enhanced by the chemical oceanography community’s Joint Ocean Flux Study (JGOFS), which added carbon cycle parameters to the observational data set. Together, using the same oceanographic cruises WOCE/JGOFS provided unprecedented high-quality observational coverage of the World Ocean.
By time these programs had ended, concern over the changing climate meant that a time-series of observations were needed. However, the many transects of WOCE/JGOFS were far too expensive for the countries involved to repeat. So, during the 2000’s through CLIVAR (Climate and Ocean Variability, Predictability and Change) particular WOCE/JGOFS transects were re-occupied and the Global Ocean and Carbon Repeat Hydrography Program was born. As in WOCE individual countries volunteered to support measurement of particular lines.
But one time re-occupation is not enough when we are seeking to understand the effects of anthropogenic climate change on the ocean and the effects of a changing ocean on climate.
In 2015 GO-SHIP came into being. Its goal is to continue to provide the best possible, surface to bottom, observations of the ocean by repeatedly re-occupying specific transects, many of which were first measured during WOCE and some of which have a history going back to the IGY 1957-1958.