burning fossil fuels coal, natural gas, and oil takejto tabuľke carbon emissions 68 percent of electricity emission of carbon dioxide a staggering 87 percent 90 percent of all human-produced CO2 report 87 percent of carbon emissions come from fossil fuel use report greenhouse effect released by human activity Carbon dioxide emissions steady increase in the volume of these emissions burning of fossil carbon emissions released by human activity major factor in anthropogenic climate change WhatsYourImpact.org