Radiocarbon in Tropospheric CO2 and Organic Materials from Selected Northern Hemisphere Sites

Abstract

Radiocarbon was measured in atmospheric CO2 from La Jolla, California and in living organic materials from six sites in the northern hemisphere. Atmospheric CO2 Delta-14C values from La Jolla agreed with those previously published records from China Lake, California (Berger et al.1987) and Vermunt, Austria (Levin et al.1985). Delta-14C values of fruit and grain samples that grew during 1980 agreed with the atmospheric CO2 Delta-14Cmeasurements. Most of the Delta-14C results of fruit and corn samples stored since the 1940s agreed with tree-ring Delta-14C values for the same time period. In general, agreement was found between the atmospheric CO2 or tree-ring Delta-14C records available for the Northern Hemisphere and the Delta-14C signatures of rapidly exchanging organic matter pools examined in this study. Exceptions were the Delta-14C values of carbonate from egg shells and that of organic carbon from egg insides, which demonstrate that bicarbonate and organic carbon within the egg follow different biochemical pathways.