Transfer of Bomb 14 C to the Ocean Surface

Abstract

Additional 14 C data from the atmosphere and ocean have been provided since the ninth 14 C conference in 1976. At the moment, one sampling station in the troposphere in each hemisphere seems to give sufficient accuracy for exchange studies. The 14 C concentration in the troposphere in December 1978 constituted a mean value of 30 ± 1 percent (Δ 14 C) above normal level, a concentration that has been reduced to about one half during 12 years. 14 C measurements have been performed with intervals of 1 to 4 months in the surface water of the Atlantic, Pacific, and Indian Oceans. In addition to the 14 C data observed, the salinity and temperature are also measured. Because of earlier objections against storing sea water in steel drums on board ships for months before treatment, the CO 2 has now been flushed out immediately after collection. The reliability of previous measurements has been confirmed with 10 parallel samples. 14 C concentration in ocean surface on each location shows some seasonal variation due to variable exchange of water with deeper layers.