The CO2 greenhouse effect and the thermal history of the atmosphere.
The influence of the expected rise of CO2 content in our atmosphere upon terrestrial temperature is uncertain. A significant increase in temperature could be threatening to certain aspects of terrestrial biology. On the other hand, it is a general consensus among paleobiologists that the Earth possessed a CO2 atmosphere in the past billion years, without dramatic temperature variations endangering the continuity of life. In order to clarify this problem, and to contribute to the understanding of the CO2 greenhouse effect on Venus we have computed the absorption spectrum of CO2 for a wide range of atmospheric concentrations. More than 2500 spectral lines of the 15 micron band were taken into account in our line-by-line calculation. We have used an empirical exponential line-shape function at the line edges. Our results agree with the experimental data of F. W. Taylor. The estimated increase in surface temperature does not reach the boiling point of water even for CO2 concentrations thousands of times larger than the present concentrations. Higher energy (>666 cm-1) CO2 bands and/or an increase in atmospheric H2O may, however, amplify the greenhouse effect.
Marx
G
G
Department of Atomic Physics, Eotvos University, Budapest, Hungary.
Miskolci
F
F
D001272:Atmosphere / Q000737:chemistry*; D002245:Carbon Dioxide / Q000032:analysis* / Q000737:chemistry; D018534:Earth, Planet; D019419:Evolution, Planetary; D017752:Greenhouse Effect; D006358:Hot Temperature; D008962:Models, Theoretical
D002245:Carbon Dioxide