With growing concern about climatic changes that could result from increased atmospheric carbon dioxide, it is appropriate to use the improved statistics on the production and use of fossil fuels which are now available and to review the CO2 discharges to the atmosphere from fossil fuel burning. Data on global fuel production and the chemical composition of these fuels have been re-examined and an attempt has been made to estimate the fraction of fuel which is used in the petrochemicals industry or otherwise not soon oxidized. Available statistics now permit more systematic treatment of natural gas liquids than in earlier calculations. Values used for combustion efficiency and non-fuel use on a global scale still require some estimation and extrapolation from United States data but can be bounded with sufficient precision that they add little uncertainty to the calculation of global CO2 emissions. Data now available permit the computation to be made with confidence that there are no major oversights. The differences from earlier calculations of CO2 emissions are minor, well within the uncertainty limits in the data available. The fundamental problems of assembling a data set on global fuel production limit the utility of striving for too much precision at other steps in the calculation. Annual CO2 emissions retain an uncertainty of 6–10%.

Results of the calculations for 1980 through 1982 show decreases from 1979 CO2 emissions. This is the first time since the end of World War II that the emissions have decreased 3 years in succession. During the period following the 1973 escalation of fuel prices, the growth rate of emissions has been less than half what it was during the 1950s and 1960s (1.5%/year since 1973 as opposed to 4.5%/year through the 1950s and 1960s). Most of the change is a result of decreased growth in the use of oil.