A model of nutrient and carbon cycles in the North Atlantic is formulated, and water flow rates, eddy mixing coefficients, particle fluxes and CO2 gas exchange rates are calculated. The model incorporates geostrophy, wind-driven Ekman fluxes and budget equations for a suite of seven tracers. Geostrophic transports are based on Levitus' (1982) climatological data, and nutrient distributions are obtained from historical station data. The model is solved by linear programming. Budgets of mass, heat, salt, oxygen, phosphate, nitrate, silicate, CO2, and alkalinity can be satisfied simultaneously in the North Atlantic. Water transports in the model depend largely on the geostrophic flows derived from the climatological data and agree quantitatively with independent transport calculations in the northern North Atlantic but seem to underestimate the shallow circulation and the upwelling in the tropical Atlantic. Meridional heat fluxes are northward in the whole model domain, and the pattern of air-sea heat fluxes agrees with bulk formula estimates. Nutrient budgets in the tropical and subtropical Atlantic place strong constraints on shallow diapycnal mixing coefficients where the values are small and well determined (between 0 and 0.2 cm2/s). They are poorly determined in the deep water. ¿ American Geophysical Union 1988