CO₂ release during combustion explains how energy flow, matter cycling, trophic transfer or carbon movement is represented, measured or limited within ecosystems.
Coverage 2019–2019 · Updated 16 Jul 2026
Combustion of biomass, peat, coal, oil and natural gas oxidizes stored carbon and releases carbon dioxide to the atmosphere.
These stores formed at different times: biomass stores recent carbon, peat accumulates over longer periods, and coal, oil and natural gas contain ancient geological carbon. Burning transfers that stored carbon rapidly to atmospheric CO₂.
Lightning can ignite biomass naturally, but human burning of biomass and fossil fuels has greatly increased combustion rates and the flux of stored carbon to the atmosphere.
Complete combustion of methane in natural gas forms CO₂ and water; burning coal, oil, peat or wood likewise transfers their carbon to atmospheric products.
Combustion moves existing carbon—it does not create carbon atoms. Incomplete combustion can also form carbon monoxide or soot, but CO₂ release is the required main flux.
This objective is assessed through multiple choice, commonly using Calculate / Compare / Contrast.
Calculate / Compare / Contrast / Identify / State
Build the answer around this relationship: CO₂ release during combustion must be linked to the correct source, store, transfer or loss process.
Reversing photosynthesis and respiration arrows in carbon-cycle diagrams.
Representative question
The graph shows how the worldwide use of fossil fuels has increased from 1800 to 2019.
How has the increased combustion of fossil fuels contributed significantly to global warming?
The heat released raises the temperature of the air.
Combustion causes ozone depletion, which enhances the greenhouse effect.
Carbon dioxide produced by combustion prevents radiation from the Sun reaching Earth.
The products of combustion absorb long wave radiation.
