API DR 141:1991

INTRODUCTION The analysis and interpretation of recent atmospheric, oceanographic, and earth sciences data suggests that significant changes in current global climate patterns may occur as a result of the accumulation of carbon dioxide (CO2) and other greenhouse gases in the Earth's atmosphere. The nature of area-or region-specific climate shifts are still uncertain with regard to type (i.e., temperature change, precipitation modification, change in frequency of severe storms, sea level fluctuations, etc.), magnitude, and timing. Given the possible severe and irreversible consequences of climate change to global socio-economic parameters, further study of greenhouse gas emission rates and emission reduction techniques is warranted. Carbon dioxide is hypothesized to contribute approximately half of the increasing concentrations of greenhouse gases that are potentially creating shifts in global climate patterns. The atmospheric concentration of CO2 has increased from about 280 ppm in 1800 to 353 ppm in 1990 (Houghton et al., 1990). The current rate of increase in atmospheric CO2 concentration is 0.5 percent per year (Houghton et al., 1990). Although natural exchanges of CO2 between the atmosphere and the biosphere (oceans, biomass, soils) are estimated in excess of 200 billion tons per year of carbon, the current 5.5 billion tons of carbon emissions (equivalent to 20.2 billion tons of CO2) resulting from fossil fuel combustion is thought to be a primary factor in the rise in atmospheric CO2 concentration in the past 180 years (Lash of and Tirpak, 1989). Between 0.4 and 2.6 billion tons of carbon emissions (1.5 to 9.5 billion tons of CO2) are attributed to deforestation. The largest sources of anthropogenic CO2 are from fossil fuel combustion, including coal, oil, and natural gas. Coal and oil each contribute about 40 percent with natural gas contributing about 20 percent to the total fossil fuel emissions of CO2. Because of the large part CO2 plays in estimates of total climate change potential, coal and oil can each be expected to contribute about 20 percent of the total change. Consequently, the examination of the energy industries I important in understanding the emissions from such sources in terms of potential impacts to global climate change.