The anthropogenic &dgr;13C change for the time period 1968 to 1991 was determined based on calculations of the preformed 13C/12C of dissolved inorganic carbon (DIC) distributions on isopycnal surfaces in the main thermocline of the Pacific, North Atlantic and South Indian Oceans. The time rate of change of preformed &dgr;13C (the 13C Suess effect) along isopycnals was calculated using CFC-derived water ages and yields a time history of the surface water &dgr;13C change at the isopycnal outcrop location. The surface ocean Suess effect recorded on isopycnals decreased with increasing outcrop latitude from approximately -0.2? decade-1 within the subtropics to around -0.1? decade-1 in the subpolar oceans. In the Pacific Ocean these surface &dgr;13C change rate reconstructions agree, both in magnitude and meridional trend, with direct observations of surface ocean &dgr;13C changes reported from time series measurements and from comparisons of surface water &dgr;13C of DIC measurements in 1970 and 1993. A global ocean average surface &dgr;13C rate of change of -0.15¿0.04? decade-1 is determined, which is slightly smaller than a previous time series data and model-based estimate (-0.171? decade-1, [Bacastow et al., 1996]). Depth integrations of the 13C reconstructions in the Pacific, Indian, and Atlantic Oceans, when combined with these previous individual depth profile comparisons and Geochemical Ocean Sections Study bomb 14C inventories [Quay et al., 1992], imply a global depth-integrated &dgr;13C change rate of -9.7¿2.4?myr-1 over the time period 1970--1990. These results imply a net oceanic CO2 uptake rate of 1.9¿0.9Gt C yr-1 over the time period 1970--1990 when applied to an atmospheric 13CO2 and 12CO2 budget. ¿ 1999 American Geophysical Union