Earth's Atmosphere: The Carbon Cycle

Earth’s Atmosphere: The Carbon Cycle

• The Carbon Cycle refers to the continuous process wherein carbon is exchanged between the Earth, its atmosphere, and living organisms.

• Carbon dioxide (CO2) in the Earth’s atmosphere is vital for the process of photosynthesis. During this process, green plants absorb carbon dioxide and water from the environment, convert these into glucose (a type of sugar) acting as their food, and release oxygen.

• Carbon is then passed into animals and humans when they consume plants. It is returned to the atmosphere as CO2 when plants, animals, and humans respire.

• When plants and animals die, they decompose with the help of decomposers. During the process, the stored carbon is released back into the atmosphere as CO2.

• Stored carbon is also released into the atmosphere during combustion, i.e., the burning of fossil fuels such as coal, oil and natural gas, and wood. This contributes to the Greenhouse Effect and global warming.

• Deforestation, or the mass cutting of trees, leads to an increase in CO2 in the atmosphere because fewer trees remain to absorb the CO2 for photosynthesis.

• In a balanced ecosystem, the amount of CO2 in the atmosphere remains fairly constant because the rate of carbon dioxide release through respiration, decomposition, and combustion is about the same as the rate of CO2 absorption by photosynthesis.

• Also, some carbon is locked away in sedimentary rocks and oil reserves over millions of years through the process called carbon sequestration. The use of these resources increases the amount of CO2 in the Earth’s atmosphere.

• Understanding the Carbon Cycle is crucial to addressing climate change as it helps us understand the impact of human activities such as deforestation and burning of fossil fuels on the atmospheric carbon concentration.