The Carbon Cycle (including human influences)

The Carbon Cycle

Carbon, one of life’s essential elements, circulates through the environment by means of the carbon cycle.
The cycle consists of key reservoirs - the atmosphere, terrestrial biosphere (which includes freshwater systems and non-living organic material, such as soil carbon), oceans, and the sediments including fossil fuels.
Notable processes that facilitate the carbon cycle include photosynthesis, respiration, decay, combustion of fossil fuels, and calcification.

Photosynthesis is the process through which green plants, algae, and some bacteria absorb carbon dioxide from the atmosphere, converting it into glucose (and thus storing the carbon) and releasing oxygen.
The process of respiration in both plants and animals returns carbon dioxide to the atmosphere, counterbalancing photosynthesis.

Oceans are crucial to the carbon cycle. In fact, they store a larger quantity of carbon than the atmosphere and the terrestrial biosphere combined.
Carbon enters the ocean layers primarily by the dissolution of atmospheric carbon dioxide, which is then used by photosynthetic marine life.

Marine animals create shells from calcium carbonate (CaCO3). After these animals die and decay, the calcium carbonate remains and can result in limestone sedimentation.
Over millions of years, this sedimentary rock can be subject to high pressure and temperature changes, leading to geological processes that transform sedimentary carbon into fossil fuels.

Decomposition or decay of dead organic material (or detritus) releases carbon dioxide back to the atmosphere and soil.

Human activity affects the carbon cycle primarily through fossil fuel combustion and deforestation.
Burning fossil fuels releases carbon dioxide which had been stored for millions of years, increasing the atmospheric concentration of the gas.
The “greenhouse effect” is intensified by the increased concentration of carbon dioxide, contributing to global warming.
Deforestation reduces the extent of forests and thus the amount of carbon dioxide absorbed from the atmosphere through photosynthesis.

The changing climate and increased level of carbon dioxide in the atmosphere affect ecosystems and biodiversity.
Changes include ocean acidification, from more CO2 dissolving into the ocean, which has deleterious effects on many marine species, especially those that form shells.
Managing and mitigating the human impact on the carbon cycle are crucial challenges for the preservation of our planet. This can be done by reducing CO2 emissions, reforestation efforts, and improving carbon capture technologies.