Extensive measurements of CO2 fugacity in the North Pacific surface ocean and overlying atmosphere during the years 1985--1989 are synthesized and interpreted to yield a basin-wide estimate of ΔfCO2. The observations, taken from February through early September, suggest that the subtropical and subarctic North Pacific is a small sink for atmospheric CO2 (0.07 to 0.2 Gton C (half year)-1 for the region north of 15 ¿N). Objective analysis techniques are used to estimate uncertainty fields resulting from constructing basin-wide contours of oceanic fCO2 on the basis of individual cruise transects. The uncertainties are significant and imply that future sampling programs need to recognize that estimating oceanic uptake of anthropogenic CO2 from ship-transect observations of oceanic fCO2 alone will require very extensive sampling. ¿ American Geophysical Union 1996