Atmospheric net transport of water vapor and latent heat across 60°S

The mean annual moisture flux across 60°S is estimated using results of numerical analyses produced by the U. S. National Centers for Environmental Prediction and the European Centre for Medium‐Range Weather Forecasts for the 7‐year period 1985–1991. The atmospheric data indicate a net poleward transport of 17.06 kg m−1 s−1 or 10.74 Tt yr−1. The mean annual moisture transport divergence for the area poleward of 60°S is estimated using a combination of surface and near‐surface data (precipitation and evaporation for the Southern Ocean, net surface accumulation and seaward drifting snow transport for the Antarctic ice sheet). The mass exchange rates at the ice sheet–atmosphere and ocean‐atmosphere interfaces are integrated strictly for the area between 60°S and 70°S and are combined with the results of a preceding surface data estimate of transport divergence for the area poleward of 70°S. The surface data are a combination of diverse sets representative of various multiyear periods distributed through 1941–1990 and indicate a poleward transport of 18.60 kg m−1 s−1 or 11.79 Tt yr−1 across 60°S. The estimates based on atmospheric and surface data show remarkable agreement (the difference is well within the error estimates) and indicate net atmospheric transports of water vapor and latent heat poleward across 60°S of 17.8 kg m−1 s−1 and 50 MJ m−1 s−1, respectively.