Carbon dioxide in Earth's atmosphere atmosphere, oceans, soil, rocks, and volcanism. Both carbon cycles are intrinsically interconnected and atmospheric gaseous carbon dioxide facilitates the carbon cycle. Natural sources of atmospheric carbon dioxide include volcanic outgassing, the combustion of organic matter, wildfires and the respiration processes of living aerobic organisms. Man-made sources of carbon dioxide include the burning of fossil fuels for heating, power generation and transport, as well as some industrial processes such as cement making. It is also produced by various microorganisms from fermentation and cellular respiration. Plants, algae and cyanobacteria convert carbon dioxide to carbohydrates by a process called photosynthesis. They gain the
Ocean storage of carbon dioxide dioxide is 10,000 years for a 50 m deep lake. This number is decreased by more than 25 times with currents from ocean bottom storms. Sites would be chosen based on ocean floor depth, seismic and volcanic activity, and the presence of CaCO deposits that could increase the rate of carbon mineralization. Some sites proposed for storage at depths greater than 6 km include the Indonesian Sunda trench, the Japanese Ryukyu trench, and the Puerto Rico trench. Researchers are studying how ecosystems are affected before and after injection of liquid carbon dioxide through "process studies, surveys of biogeochemical tracers, and