The use of radiocarbon (Δ14C) as a tracer for oceanic processes generally requires differentiation of naturally occurring radiocarbon from the bomb component produced by atmospheric nuclear weapons testing. We present a new separation method based on the strong linear correlation between Δ14C and potential alkalinity. Unlike previous techniques the new algorithm is applicable at all latitudes. Additionally, the potential alkalinity method provides an estimate of surface ocean prebomb Δ14C concentrations. Predictions with the technique appear to be unbiased and have uncertainties which are less than previous techniques.