The Carbon Cycle is a major component of the planet's biogeochemistry. In the lithosphere and biosphere, carbon plays an important role in the creation of biomass as well as in decomposition. The carbon cycle in the hydrosphere, particularly in the oceans, is less well known. We do know, however, that the oceans play a vital role in the carbon cycle, as they act as an important sink for carbon as it is rapidly exchanged with the atmosphere. The carbon cycle in the oceans involves both organic and inorganic compounds. The distribution of these carbon forms is then largely controlled by solubility and biological pumps. The solubility pump works because CO2 is more than twice as soluble in cold water as in hot water. This allows carbon to be removed from the atmosphere at the poles and then pumped into the depths of the ocean which contain this similarly cold, high-density water. The biological pump is driven by ocean biota. When CO2 is absorbed from the atmosphere into the oceans, it is converted to dissolved inorganic carbon (DIC). At the ocean surface, the primary production of marine phytoplankton then transforms this DIC into organic matter. Some phytoplankton also have the ability to combine dissolved calcium with dissolved carbonate to create calcium carbonate (CaCO3). This calcium carbonate is used to build the hard coatings of many marine organisms, from small plankton such as coccolithophores and phytoplankton to larger organisms such as molluscs, crustaceans and echinoderms. The biological pump can mainly be explained by the cycle of these organisms and their shells. When an organism dies, the carbon fixed in its soft or hard tissues is mainly contained in the upper level...... middle of paper ......on which draws CO2 from the atmosphere to the depths of the oceans. As always, much more research needs to be done on this CO2 removal option and better determine the positive and negative effects. The carbon cycle has been proven to be essential to Earth's biogeochemical cycles, but there is still much to learn about the processes. that occur in the Earth's oceans. Whether by natural transfer from the atmosphere or by anthropogenic pumping, CO2 levels in the oceans are increasing. Many studies have been carried out to try to understand the effects that this increase will have on the oceans and their biogeochemical cycle, and most have been negative. These negative effects, such as dissolution of calcium carbonates and hypercapnia on water-breathing organisms, can have long-term effects on populations, species, and the overall ocean food web..