On Meridional Heat Transports in the World Ocean

Abstract

Updated estimates of meridional heat transport in the Atlantic Ocean water body derived from the surface energy badget agree with the evaluation of hydrographic sections, annual mean northward transports being about 8 and 11 × 1014 W at 30°8 and 25°N, respectively. For the World Ocean as a whole, a southward transport of 6 × 1014 W is obtained at 60°S. Concerning the satellite-derived not radiation at the top of the atmosphere, the five data sets published in the literature are adjusted to form a zero annual mean for the globe as a whole; the required adjustments are ±10 W m−2 for the various sets. Even so, the required poleward heat transport in the atmosphere-ocean system obtained from the five data sets differs conspicuously, with a range of 20 × 1014 W at 30°N. This range may reflect observational errors and real interannual variability. The comfortable numerical agreement notwithstanding, plausible error tolerances far exceed the differences between the heat transport estimates derived by various independent methods.