Geological Carbon Cycle:

            Geological carbon cycling occurs over long periods of time. The time frame can span to millions of years before the cycling of an element is totally completed. The cycle can be altered by chemical and mechanical weathering.

            The process begins with atmospheric carbon dioxide (CO2) combined with water (H2O) to create carbonic acid. Over time, minerals located on the earth’s surface reacted with those elements in the atmosphere yielding minerals with carbonate (limestone, dolomite, chalk, shells, diamond graphite, coal). Different carbonate minerals are formed when excess materials such as plants or other rock is combined with the carbonic acid equation. After erosion the carbonate is brought to the ocean by rain water in its dissolved state. In the ocean, the carbonate settles at the bottom where it creates layers of sedimentary rock. Through the movement of tectonic plates the carbon that is found is the sedimentary rock is pushed deeper down into the earth. The carbonate minerals in the sedimentary layers melt due to exposure to the extreme rise is temperature from being closer to the core and the enormous pressure of gravity deep beneath the surface of the earth. The carbonate in its liquefied state easily mixes with surrounding minerals where it becomes gaseous carbon dioxide and lava. The release of these compounds can result from volcanic eruptions and hot springs. These events result in carbon being returned to the atmosphere and earth.

Biological Carbon Cycle

            Biology also plays a significant part in the transport of carbon as it cycles through the ocean, land and atmosphere. All life relies on the energy produced in the breakdown of the processes photosynthesis and respiration. In the atmosphere, plants take in carbon dioxide during the process of photosynthesis. They use the energy from the sun to change the atmospheric carbon dioxide into sugar. During the day light, CO2 from the atmosphere is absorbed by the leaves on the plants. However, without solar energy at night, photosynthesis stops. When plants loose their leaves during the winter, there is a build up of CO2 in the northern hemisphere. This access CO2 keeps the atmosphere warmer, whereas, too little CO2 will cause a temperature drop.

            The process of respiration is varies depending on the organism. In animals, respiration breaks down oxygen and combined with sugars, is released back into the atmosphere as carbon dioxide (CO2). Respiration in plants is not predicated on photosynthesis, and at night when photosynthesis stops, respiration continues. In plants, respiration breaks down oxygen and combined with sugars, is released into the atmosphere as carbon dioxide (CO2). Decomposers play an important role in the cycle of carbon. On land, decomposers such as bacteria and fungi are responsible for the decay of organic matter (waste, leaves and dead animals). They decompose the material and release CO2 into the air.

            Not all carbon dioxide is utilized by plants and animals. The ocean also serves as a location where dissolved CO2 is present. The dissolved CO2 creates calcium carbonate which forms the shells for mollusks. At the end of a mollusks life, the body, composed of soft tissue, decays and the shell falls to the bottom of the ocean. There, they accumulate and are compressed by gravity and are undisturbed for many years until they become sedimentary rock such as limestone, dolomite and chalk. Trees that decay and sink to the bottom of a large body of water form oil. Small plants that go through that same process form coal. Only non-calcium that contains organic matter makes fossil fuel. These fossil fuels can be burned and released back into the atmosphere as CO2.