Naturally occurring CO gas ₂ it is also a by-product of combustion fossil fuels (such as oil, gas and coal), combustion   biomass , of land use changes (LUC) and industrial processes (e.g. cement production). It's the main one anthropogenic greenhouse gas ( GHG ), which affects the radiation balance of the Earth. It is the reference gas against which other greenhouse gases are measured and therefore has a global warming potential (GWP).

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