CC is probably the most studied impact regarding cement production and it is measured in terms of carbon dioxide equivalent (kg CO2 eq). In fact, 1 kg CO2 is equal to 1 kg CO2 equivalent, while for other compounds, for example, methane, 1 kg can be equal to 25 kg of CO2 equivalent.
However, due to the large amounts of CO2 emissions inherent to clinker production, these emissions are the main contributors to climate change in this case. CC world average of dioxide emitted from cement production is about 0.8e1.0 t of carbon dioxide per t of Portland cement