Having considered the rudiments of climate and human habitability, the next question to ask is how does the ocean circulation impact the most fundamental aspect of Earth ecology, i.e., the distribution of the ocean’s primary producers, the phytoplankton? These microscopic plants, which utilize CO2 and produce O2 as a product of photosynthesis are the foundation for just about everything that lives in the ocean. Whereas it is estimated that the ocean’s phytoplankton comprise only about 1% of the Earth’s photosynthetic biomass, these phytoplankton account for nearly half of the world’s primary productivity.