On the interannual variability of poleward transport and storage of heat in the ocean-atmosphere system

Abstract

Published satellite measurements of net radiation at the top of the atmosphere show anapparent imbalance of the global annual mean of the order of ± 10 W m−2, while for the required poleward heat transport at the latitudes of largest transport 30–40 °N and S, a range of about 200 and 100 × 1013 W, respectively, is indicated. It is suggested that (i) part of theapparent interannual variability of global-mean net radiation at the top of the atmosphere may bereal, while part is due to deficiencies in sampling, sensing, and processing; (ii) year-to-year variations of temperature in the top layer of the World oceanmay be large enough to account for a substantial portion of the apparent interannual variability of global-mean net radiation at the top of the atmosphere; (iii) the interannual variability of meridional heat transport in the combined hydrosphere-atmosphere system may in large part result from processes in the ocean. The currently available oceanic observations and satellite data are insufficient to weigh even the relative importance of interannual variability in (a) meridional heat transport in the combined atmosphere-ocean system, (b) meridional heat transport in the global ocean, and (c) heat storage in the global ocean, so that none of these three components can be considered negligible.