
The oceans have absorbed almost all of the excess heat generated by increasing atmospheric greenhouse gas concentrations and a large fraction of anthropogenic carbon dioxide, with profound implications for ecosystems and the climate system. Ship-based hydrographic surveys are the only current means for simultaneously measuring physical, biological, and biogeochemical properties of the global oceans from the surface to the seafloor and are a crucial resource for understanding ocean change and its role in the climate system. Building on global hydrographic surveys underway since the...