Heat transport by ocean currents

Several authors have calculated the heat transport by ocean currents from maps of heat budget components. Their results suggest the importance of the energy transported by ocean currents, which at some latitudes exceeds one-third that transported by the atmosphere. This and the recent appearance of new maps of the heat budget components gave rise to this paper. We compute the heat flux divergence for the Atlantic, Indian, and Pacific oceans separately. The heat budget method is used to compute the heat flux divergence. By Green's theorem the meridional heat transport can be computed by integrating the heat flux divergence with respect to area. As the necessary boundary conditions we take for all oceans the heat transport across 70°S to be zero. In general, the heat flux divergence curves and the heat transport curve agree well with those given previously. A deviation from earlier results is noted for the North Pacific. Any differences are due to the new values of the heat flux divergence. For the first time heat flux divergence curves are given for the Indian and Pacific oceans separately. Of particular interest are the large values of the heat flux divergence in the northern Indian Ocean. The components in the heat budget of the oceans are, however, subject to some error in measurement, especially the radiation balance of the earth's surface. The relative consistency of the results obtained by this method gives us some confidence in their validity.