Which organisms remove carbon dioxide from the atmosphere?

Question: Which organisms remove carbon dioxide from the atmosphere?

Carbon dioxide (CO2) is a greenhouse gas that contributes to global warming and climate change. It is released into the atmosphere by human activities such as burning fossil fuels, deforestation, and agriculture. To limit the rise in global temperature, it is necessary to reduce CO2 emissions and increase CO2 removal from the atmosphere.

There are different methods of removing CO2 from the atmosphere, such as carbon capture and storage (CCS), direct air capture (DAC), and ocean-based solutions. However, one of the most natural and effective ways of removing CO2 is through the process of photosynthesis carried out by living organisms.

Photosynthesis is the process by which plants, algae, and some bacteria use light energy to convert CO2 and water into oxygen and organic molecules, such as glucose. This reduces the amount of CO2 in the atmosphere and increases the amount of oxygen. Photosynthesis also stores carbon in the biomass of the organisms and in the soil.

According to a study by NASA, plants remove about 120 billion tons of carbon from the atmosphere every year through photosynthesis.  The main groups of organisms that perform photosynthesis are:

- Land plants: These include trees, shrubs, grasses, crops, and other vegetation that cover about 30% of the Earth's surface. Land plants are estimated to remove about 80 billion tons of carbon per year from the atmosphere.  They store carbon in their leaves, stems, roots, and wood. When they die or are harvested, some of their carbon is transferred to the soil or released back to the atmosphere through decomposition or burning.

- Phytoplankton: These are microscopic algae that float in the upper layer of the ocean where they receive sunlight. Phytoplankton are responsible for about half of the global photosynthesis and remove about 40 billion tons of carbon per year from the atmosphere.  They store carbon in their cells and organic matter that they produce. When they die or are eaten by other organisms, some of their carbon sinks to the deeper ocean where it can be stored for long periods of time. This is known as the biological pump.

- Cyanobacteria: These are bacteria that can perform photosynthesis and are found in various environments, such as freshwater, marine, and terrestrial ecosystems. Cyanobacteria are thought to be among the oldest photosynthetic organisms on Earth and have played a key role in shaping the Earth's atmosphere by producing oxygen and removing CO2. Cyanobacteria can remove about 0.5 billion tons of carbon per year from the atmosphere.  They store carbon in their cells and organic matter that they produce.

In summary, photosynthesis is a vital process that removes CO2 from the atmosphere and produces oxygen. The main organisms that perform photosynthesis are land plants, phytoplankton, and cyanobacteria. Together, they remove about 120 billion tons of carbon per year from the atmosphere and store it in various forms.