The document discusses several factors that influence ocean circulation, including temperature, salinity, wind, and the planet's rotation. It also describes thermohaline circulation, which is driven by temperature and freshwater inputs that affect salinity. Areas with declining oxygen content, known as oxygen minimum zones, are seen in tropical parts of the major oceans. The bibliography cites several sources on topics like changes in ocean oxygen inventory associated with global warming, the thermohaline circulation, and fossil fuel subsidies.