Climate change, the carbon cycle, and greenhouse gases

Not familiar with some basic concepts of greenhouse gases, the carbon cycle, and global warming?

Here is a brief explanation to fill you in.

Our planet has a natural carbon cycle that links the carbon in the atmosphere to the carbon in the biosphere (organisms on the planet). Two of the most potent greenhouse gases, carbon dioxide and methane, are part of this cycle. Carbon dioxide is removed from the atmosphere by plants and microbes that that convert it into carbohydrates and other molecules essential for life (methane can also be used in a similar fashion by certain microbes). In turn, animals eat these plants and the carbon-based molecules are passed through the food chain until they converted back into carbon dioxide and returned to the atmosphere as the biomass decomposes after expiry. During the history of our planet, these greenhouse gases have always been in balance within the carbon cycle and do not normally accumulate.

diacarbon-cycle

Enter fossil fuels…

Fossil fuels are buried deep within the earth, and while they are composed of carbon-based molecules, they are not part of the normal carbon cycle. When fossil fuels are burned (in cars, for example), the carbon that was trapped within the ground is liberated as carbon dioxide. This upsets the carbon cycle and creates an accumulation of greenhouse gases that cannot be easily recaptured.

Greenhouse gases get their name from the effect they have on the planet. These gases actually prevent heat from radiating out from the planet into space. Normally this is a good thing and has allowed the planet to maintain a suitable temperature for life to survive. Unfortunately, our increased use of fossil fuels over the past century has corresponded with an increase in greenhouse gases. This in turn has corresponded with an increase in the average temperature of the planet (global warming). This has led to a noticeable change in the climate patterns across the Earth. The melting of glaciers and polar ice caps, severe storms, loss of ecosystems and increased desert areas are a few of the observable effects of global warming. Humans have greatly impacted the health of our planet, and it is up to us to help repair the damage!