The carbon cycle is the rotating of carbon between the earth’s oceans, atmosphere, ecosystem, geosphere, and everything in between. Carbon makes up everything from the sugars we eat to the skin on our bodies to the sun itself. The cycle happens when a herbivore eats a plant and transforms the plant material into amino acids and sugars. Next, the body uses this newly transformed carbon to grow bones or other biological elements. When we die the carbon we have inside of us is decomposed by microbes or eaten by other organisms. Every time we convert some type of building block, we utilize respiration and that produces CO2 which is sent back into the atmosphere as a gas. This gas can be reabsorbed by plants to make sugars via photosynthesis, stay in the atmosphere, or enter the oceans through molecular diffusion and react to produce Carbonic Acid. This is later diffused by chemical reactions to re-enter the cycle.
This leads us to designate some processes as carbon sinks and the other processes as carbon sources. Carbon sinks are oceans, forests, soils, or anything that naturally retains carbon. A source produces carbon like burning fuels, breathing, decomposition, and land use. The cycle is continuously exchanging carbon between sources and sinks. The problem arises in the Law of Conservation of Mass (Antoine Lavoisier); matter can neither be created nor destroyed. When we burn something we change the state of matter to gas from solid and this takes the form of carbon. The less carbon that is in a solid state (fossil fuel, biomass, soil, trees, etc.) means more is in the gaseous state, causing problems for humans. According to Princen, Manno, and Martin, “the only safe place for fossil fuels is in place, where they lie, where they are solid or liquid (or, for natural gas, geologically well contained already), where their chemistry is mostly complex chains, not simple molecules like carbon dioxide, that find their way out of the tiniest crevices, that lubricate tectonic plates perpetually under stress, that react readily with water to acidify the oceans, and that float into high places filtering and reflecting sunlight, heating beyond livability the habitats below.”
When carbon is in the gaseous form it becomes a greenhouse gas trapping a specific type of radiation from the sun, longwave radiation. Longwave radiation excites molecules and results in heat emission causing the planet, as a whole, to become warmer. While carbon dioxide only makes up 0.04 per cent of the atmosphere, it plays the largest contributing role to the trapping of longwave radiation at 63 per cent, compared with methane, nitrous oxide, and chlorofluorocarbons which play smaller roles. Greater energy demand with less carbon sinks means greenhouse gases increase, which in turn means more radiation is trapped leading to increased temperature.
It is also important to note carbon levels in the atmosphere have changed throughout history. February 2015 had the highest carbon levels to date since the Oligocene era 23 million years ago.It is a natural cycle that has highs and lows but we are increasing it at a rate never seen before, with March 2015 hitting 402.43 parts per million (ppm) and March 2016 at 405.41 ppm. This year has seen an increase in 2.98 ppm. By comparison, the Oligocene era decreased 0.00009091 ppm per year
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