This gas makes up about 0.04% of Earth's atmosphere and is what plants take in during photosynthesis
What is carbon dioxide (CO2)?
Trees, grasses, and algae store carbon in their tissues, making them this type of reservoir
What are plants/producers?
Plants use sunlight to pull CO2 from the air and turn it into sugar through this process
What is photosynthesis?
Dead marine organisms sink and get buried under sediment over millions of years, eventually forming fossil fuels or rock through this process
What is sedimentation (burial)?
Power plants and cars release carbon that took millions of years to form by doing this to coal, oil, and natural gas
What is burning fossil fuels?
Oceans absorb about a quarter of human CO2 emissions, storing carbon mainly in this dissolved form
What is dissolved inorganic carbon (dissolved CO2/bicarbonate)?
When a rabbit eats a carrot, the carbon becomes part of this type of reservoir
What are animals/consumers?
Animals, plants, and decomposers release CO2 back into the atmosphere through this process while breaking down food for energy
What is cellular respiration?
This geologic event releases carbon stored deep in Earth's mantle and crust back into the atmosphere as CO2
What is a volcanic eruption?
Cutting and burning forests releases stored carbon and removes trees that would otherwise absorb CO2
What is deforestation?
Coal, oil, and natural gas are examples of this reservoir, formed from carbon buried and compressed over millions of years
What are fossil fuels?
Bacteria and fungi in soil store carbon temporarily as they break down dead material
What are decomposers?
Fungi and bacteria break down dead organisms and release stored carbon through this process
What is decomposition?
Rain reacts with carbonate rocks over long periods, slowly dissolving them and releasing or trapping carbon
What is (chemical) weathering?
Making this common building material releases large amounts of CO2 when limestone is heated and broken down chemically
What is cement (production)?
This is Earth's largest carbon reservoir, made of limestone and other carbonate rock formed from ancient marine shells
What are sedimentary rocks (the lithosphere)?
Fallen leaves, logs, and animal carcasses waiting to be broken down make up this reservoir
What is dead organic matter (detritus)?
CO2 constantly moves between the ocean surface and atmosphere through this passive process with no organism involved
What is diffusion (gas exchange)?
Coral and mollusks pull carbon from ocean water to build shells and skeletons, eventually locking carbon into rock
What is shell/skeleton formation (the biological pump)?
As oceans absorb more atmospheric CO2, seawater pH drops, an effect that harms shell-building organisms
What is ocean acidification?
Decomposing plant and animal matter builds up carbon here, where it can stay locked away for centuries
What is soil (soil organic carbon)?
Tiny floating ocean organisms pull carbon from water through photosynthesis, forming the base of this reservoir
What is phytoplankton (marine biomass)?
Wildfires release carbon stored in plant matter through this process
What is combustion (burning)?
Carbon moves from producers to consumers to top predators through this sequence
What is the food chain (feeding/consumption)?
Livestock farming and rice paddies release large amounts of this potent carbon-based greenhouse gas
What is methane?