大気中の二酸化炭素の同位体比(<特集>大気中の二酸化炭素)

概要

論文の詳細を見る
The δ^<13>C values relative to PDB were measured for carbon dioxide in air samples collected at various parts of Japan and at Mauna Loa Observatory, Hawaii in the periods of 1977 and 1978. The δ^<13>C values of the "clean air" are -7.6‰ at Hawaii and -8,1‰ Oki and Hachijo-jima islands. These values are definitely lighter than the carbon isotope ratios (-6.9‰) obtained by Keeling for clean airs collected at Southern California in 1955 to 1956. The increase in ^<12>C in atmospheric carbon dioxide is attributed to the input of the anthropogenic light carbon dioxides (combustion of fossil fuels etc.) Taking -7.6‰ to be the isotope ratio of CO_2 in the present clean air, a simple three box model predicts that the biosphere has decreased rather than increased since 1955, implying that it is acting as the doner of carbon rather than the sink.
日本地球化学会の論文
1982-12-30