Model results and observations both indicate warming of the world ocean from 1955 to 2003. Forced by reanalysis data, the model also shows that the warming of the arctic ice–ocean system is faster than the global average since the 1960s; there is a small but widespread increase in heat content of the Arctic Ocean's waters and a larger increase of latent heat embodied in the ocean's decreasing ice cover. From 1966 to 2003 the modeled mean world ocean temperature in the upper 700 m increased 0.097°C and by 0.137°C according to observations (Levitus et al., 2005); the modeled mean temperature adjusted for sea ice in the corresponding layer of the Arctic Ocean increased 0.203°C. The warming of the world ocean is associated with an increase in global surface air temperature, downward longwave radiation, and therefore net heat flux. The faster warming of the arctic ice–ocean system is associated with an amplified increase in arctic surface air temperature, downward longwave radiation, and net heat flux.