Absolute production of radiocarbon and the long-term trend of atmospheric radiocarbon.

Abstract

This paper presents simulations of the long-term trend of atmospheric radiocarbon, performed with the modified PANDORA model. The author shows that taking into account the outflow-supply carbon fluxes makes the decrease of D (super 14) C between 40 and 0 ka BP larger by 40-80 per mil, not much depending on which data (sedimentary magnetism, archaeomagnetism or (super 10) Be) is used for the scenario of relative variations of (super 14) C production. This together with the effect of CO (sub 2) increase reasonably reconciles model-simulated and observed decline of atmospheric delta (super 14) C.