Atmospheric CO/sub 2/ projections with globally averaged models

Conference · Sat Jan 01 04:00:00 EST 1983

OSTI ID:6313998

Trabalka, J R; Emanuel, W R; Gardner, R H; Reichle, D E; Edmonds, J; Reilly, J; Moore, B III

The consequences of an anticipated increase in atmospheric CO/sub 2/ concentrations from the combustion of fossil fuels and other anthropogenic activities cannot be adequately evaluated without realistic estimates of future CO/sub 2/ levels. Historic fossil fuel usage to the present, growing at a rate of 4.5% per year until 1973 and at a slower rate of 1.9% after 1973, is projected at rates of approximately 0.2 to 2.8% per year from 1975 until 2075 using an energy-economic model. Varying key parameters within the bounds of currently expected future values is used to provide bounds on CO/sub 2/ emissions projections. Atmospheric CO/sub 2/ emissions in the year 2075 are thereby projected to be in the range of 6.6 x 10/sup 15/ to 91 x 10/sup 15/ g C year/sup -1/. Annual CO/sub 2/ emissions data were used as inputs to two different global carbon cycle models. Carbon cycle model simulations used a range of year-1860 preindustrial atmospheric concentrations of 245 to 292 ppMv CO/sub 2/ based on three scenarios of biosphere conversion as additional atmospheric CO/sub 2/ source terms. These simulations yield a range of possible atmospheric CO/sub 2/ concentrations in year 2075 of from approximately 500 to 1550 ppMv, with a median of about 700 ppMv. The estimated time at which atmospheric CO/sub 2/ doubles the preindustrial level ranges from year 2025 to >2075. This forecast exercise forces quantitative definition of the assumptions and uncertainties in the global CO/sub 2/ budget. These terms form the basis of our understanding of the natural biogeochemical cycle of carbon as well as both past and future human influences on the dynamics of the global cycle. 51 references, 10 figures, 6 tables.

• Research Organization: Oak Ridge National Lab., TN (USA); Institute for Energy Analysis, Washington, DC (USA); New Hampshire Univ., Durham (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6313998
• Report Number(s): CONF-831048-4; ON: DE85002323
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
CARBON COMPOUNDS
CARBON CYCLE
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
COMBUSTION PRODUCTS
EARTH ATMOSPHERE
ECOLOGICAL CONCENTRATION
ENERGY SOURCES
FORECASTING
FOSSIL FUELS
FUELS
GLOBAL ASPECTS
MATHEMATICAL MODELS
OXIDES
OXYGEN COMPOUNDS