The ocean, the largest carbon sink on Earth, and its relationship to climate.

The sea has a direct relationship with the climate due to several physical and chemical processes. The oceans act as a climate regulator by absorbing and storing heat from the atmosphere, and they also contribute to the carbon cycle by absorbing and storing carbon dioxide (CO2) from the atmosphere.

Heat transfer in the oceans occurs in several ways: direct solar radiation, convection, and conduction.

Direct solar radiation: This is the most common way that the sun heats the oceans, and is responsible for 80% of the heat that the oceans receive.

Convection: refers to the movement of water caused by the difference in density due to temperature variation, and is responsible for 15% of the heat that the oceans receive.

Conduction refers to the movement of heat through direct contact between water and solid objects, such as rocks or sediment.

ocean circulation:

It is the continuous movement of water in the oceans, it is caused by the difference in density due to the variation of salinity and temperature. This is because salt water is denser than fresh water, and cold water is denser than warm water.

The oceanographic circulation is divided into two types:

Superficial circulation and deep circulation. Surface circulation is the movement of water near the ocean surface, and is caused by winds and currents. Deep circulation is the movement of water found in the deepest layers of the ocean, and is caused by differences in density. Both are important in regulating the climate and transporting heat from one place to another.

The carbon cycle in the sea:

It refers to the way carbon is exchanged between the atmosphere, oceans, and marine organisms. The oceans act as a carbon sink, absorbing and storing large amounts of CO2 from the atmosphere.

The process is called “biological carbon fixation” where marine organisms such as algae and plants absorb CO2 and store it in their structure, during photosynthesis.

Carbon moves between the three compartments through physical and chemical processes, including solubility, adsorption, precipitation, photosynthesis, and respiration. However, the accumulation of CO2 in the oceans also has negative consequences, such as ocean acidification and the change in the chemical composition of the water.