The Carbon Cycle: Questions and Answers For The Future

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Today’s concerns for food production, human migration, and water management are all intimately connected with the carbon cycle and how human activity affects it. If you want to take an informed position on nearly any issue that concerns the environment, you should understand how the carbon cycle works.

In this article, we will work to describe to you what the carbon cycle is, what the major carbon reservoirs are, how humans affect the cycle, and what actions humans can take to reduce their impact on the carbon cycle.

What is the Carbon Cycle?

According to the website for the National Ocean Service, the carbon cycle is the “chemical backbone of life on Earth.” The carbon cycle describes the processes through which carbon travels on the earth.

The carbon cycle is being disrupted by humans on a scale never seen before due to anthropogenic climate change. Asking “what is the carbon cycle” is a vitally important question for business leaders, policymakers, and anyone impacted by the rapid changes taking place in our environment.

The cycle is broken up into two components: the slow carbon cycle and the fast carbon cycle.

The slow carbon cycle occurs when atmospheric carbon combines with water to form carbonic acid. Carbonic acid in rainwater then falls on rocks, slowly dissolving them. These rocks form ions, such as calcium, and these ions runoff into rivers, and eventually, into the sea. Once in the ocean, these ions bond with other ions to produce calcium carbonate, a compound that is essential for undersea organisms to form shells. This carbon remains on the ocean floor until volcanic action returns it to the atmosphere.

The fast carbon cycle, on the other hand, describes a faster process for moving carbon atoms around the world. According to NASA, between 1000 to 100000 million metric tons of carbon moves through the fast carbon cycle each year. This cycle relies on the world’s oceans and life forms.

Phytoplankton (microscopic organisms in the ocean) and plants absorb carbon via photosynthesis. Plants consume carbon and create sugar (CH2O+O2), which is then consumed by plants, animals, and microscopic life. This is expelled as waste products into the soil and oceans, beginning the cycle again.

The fast carbon cycle is tightly tied to plant life on Earth, so much so that scientists track seasons and carbon levels by measuring plant growing seasons.

What are the Major Carbon Reservoirs?

The major carbon reservoirs on Earth are places where large amounts of carbon is stored and then moved through the fast and slow carbon cycles. These are:

The Atmosphere

Carbon is released from the oceans and through man-made processes and is then suspended in the atmosphere before being absorbed back into the ocean and soil. Now, this delicate balance is shifting due to human activity.

The Terrestrial Biosphere

The terrestrial biosphere includes plants, animals, forests, and soil systems across the planet. The amount of carbon that these systems can hold is reduced as people conduct large-scale manufacturing and agriculture. Crop and farmlands, which now make up over 35 percent of global landmass, hold less carbon than forests. In addition, disrupted soil that contains lower levels of soil organic matter holds less carbon than rich, healthy soil.

The Oceans

Carbon enters the oceans through the water cycle and the formation of carbonic acid from rocks. In the ocean carbon cycle, carbon, oxygen, and hydrogen are constantly exchanged between the oceans and the atmosphere. In recent years the oceans temperature has increased and become more acidic because of balance of the increase of CO2 in our atmosphere.

The Earth’s Sediments

Carbon becomes trapped in the Earth’s sediment layers by way of slow geologic processes. Carbon in these layers can be released either very slowly or very quickly, either by a volcanic eruption or human activities. Oil and other fossil fuels are examples of sediment material that humans use for energy purposes.

Where is the Most Carbon Stored?

Normally, the oceans store the most carbon. This balance is changing, however, due to human activity. Larger amounts of carbon are now transferred to the atmosphere due to disruption of precipitation and CO2 release from human manufacturing, vehicle use, and agriculture.

How Do Humans Affect the Carbon Cycle?

Human impact on the carbon cycle is substantial. Humans have inadvertently reduced or eliminated the ability of the terrestrial biosphere to absorb CO2 through land clearing and soil matter reduction. Additionally, the human use of fossil fuels to generate energy increases the number of greenhouse gases in the atmosphere. This increase in atmospheric CO2 causes global temperatures to rise, severely impacting weather, growing seasons, and water systems.

Reducing Human Impact on the Carbon Cycle

Humans are causing significant harm to the carbon-oxygen cycle by introducing more carbon into the atmosphere than ever before due to the advancements from the industrial revolution. However, we can implement a few strategies to reduce our impacts on the carbon cycle. These efforts require the cooperation of government, business, and citizens to make happen. These include:


Forests are natural carbon sinks. Carbon is easily stored in biome rich soil, trees, and plant/water systems in forests. Large-scale reforestation efforts can increase carbon sequestration and reduce global warming.


Carbon farming is the practice of transforming agricultural activities so that farms act as carbon traps and can help restore the carbon cycle. Non-till farming, mixing and rotating crops, and introducing cover crops such as clover can work to sequester carbon back into soil and plants.

Direct Air Capture

New mechanical technologies using zero-carbon output energy technologies, such as solar, can directly remove carbon from the atmosphere. As clean, cheap energy sources are developed as alternatives to fossil fuels, methods involving wind and solar energy show great promise.

Understanding the Carbon Cycle: Cool Effect Can Help

Is the question “what is the carbon cycle” important to you? Cool Effect can help you understand the effects of the global carbon cycle on your business or organization. Do you have questions about how the CO2 cycle works and what it means? Contact us! We’d love to answer your questions about carbon offset programs.