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Human activities since the beginning of the Industrial Revolution (taken as the year 1750) have produced a 40% increase in the atmospheric concentration of carbon dioxide, from 280 ppm in 1750 to 406 ppm in early 2017. This increase has occurred despite the uptake of a large portion of the emissions by various natural 'sinks' involved in the carbon cycle. Anthropogenic carbon dioxide (CO) emissions (i.e., emissions produced by human activities) come from combustion of fossil fuels, principally coal, oil, and natural gas, along with deforestation, soil erosion and animal agriculture.
Output:
what is the difference between natural greenhouse gases and anthropogenic greenhouse gases