Carbon-14 Measurements in Surface Water CO2 from the Atlantic, Indian and Pacific Oceans, 1965-1994.

In the 1960s, thermonuclear bomb tests released significant pulses of radioactive carbon-14 (14C) into the atmosphere. These major perturbations allowed scientists to study the dynamics of the global carbon cycle by calculating rates of isotopic exchange between the atmosphere and ocean waters. The Radiological Dating Laboratory at the Norwegian Institute of Technology performed 14C measurements of atmospheric CO2 from 1962 to 1993 at a network of ground stations in the northern and southern hemispheres; in addition it performed 14C measurements at high-altitude (between 9-12.6 km) during 1965 (Nydal and Lövseth, 1983, 1996). The Norwegian Radiological Dating Laboratory performed similar measurements on seawater samples collected at the ocean surface from 1965 through 1994. The resulting 14C ocean surface water database is documented here and is available from the Carbon Dioxide Information Analysis Center (CDIAC) as NDP-057A, free of charge. The data from NDP-057A, coupled with other 14C data sets, can lead to a greater understanding of the dynamic carbon reservoir and lead to a crude picture of anomalous sources and sinks at different geographical latitudes. The database is outstanding for its inclusion of early 14C measurements, broad spatial coverage of sampling, relative consistency of sampling methods, and Δ 14C calculation results corrected for isotopic fractionation and radioactive decay. This database replaces previous versions published by the author and the Radiological Dating Laboratory.