By: Jose Caceres
First we need to understand that carbon is found in fossil fuels. Fossils fuels are the result of anaerobic decomposition of the remains of plants and animals after being buried in oxygen-free environments and under specific conditions of temperature and pressure and over long periods of time (millions of years). Coal, petroleum and natural gas are fossil fuels.
Carbon based fossil fuels are a source of energy. This energy can be obtained by burning these fossil fuels. By doing this, the carbon content is released to the atmosphere, where it combines with oxygen and becomes carbon dioxide or CO2.
Once in the atmosphere the atom of carbon released when fossil fuels are burnt could potentially follow one of the following fates:
- Be consumed by plants on land via photosynthesis and become part of the food chain, which will eventually release it back to the atmosphere as CO2, or perhaps buried in an oxygen-free environment, like a swamp and potentially becoming coal.
- Taken up by the oceans where it will be dissolved and recycled. This process occurs as cold seawater absorbs carbon from the air and warm seawater releases it. This circulation process takes about 1000 years. Also, a portion of this carbon be consumed by living organisms (plankton) and thus becoming part of the ocean food chain which eventually would release it again as CO2 back to the atmosphere.
- Accumulations of dead carbon-rich organisms in the oceans become sedimentary rocks, such as limestone. These sedimentary rocks over a very long period of time (millions of years) and under very high temperature and pressure, convert into magma and get expelled back to the atmosphere as CO2 via volcanoes. Also, given the appropriate conditions, these carbon-rich organisms can become petroleum or natural gas.
With the above said, carbon atoms can literally be recycled over and over and this is what constitutes the carbon cycle.
In order to round the notion of what might happen to a carbon atom when fossil fuels are burned, it is important to highlight that burning fossil fuels is a man-made activity which disturbs the natural carbon cycle. Man-made emissions of CO2 add-up carbon to the atmosphere which otherwise would be buried underground. CO2 is a greenhouse gas and hence it has the ability to trap heat.
In synthesis: CO2 levels in the atmosphere are rising above otherwise natural levels and this is due to human activity (burning fossil fuels). CO2 enhances the greenhouse gas effect and therefore constitutes the main forcing of global warming. In the scenario that the CO2 emissions trend continues, the planet will only continue to get warmer. The trajectory of a ‘business as usual’ scenario if not reverted could bring catastrophic consequences for both the environment and humanity.
Accepting the scientific facts and act responsible by tackling the causes of global warming is crucial. As per the carbon atom, it is up to us to leave it unearthed by leaving the task of releasing it to mother nature and it is also up to us to burn it and release it as we use its energy. This later decision could not only mean the fate of the carbon atom but could also signal our own fate.
