Comment on "Dynamic surface topography: A new interpretation based upon mantle flow models derived from seismic tomography" by A. M. Forte, W. R. Peltier, A. M. Dziewonski and R. L. Woodward

In a recent paper in this journal, Forte et al. [1993] have proposed a model of global dynamic topography with an amplitude of three kilometers (six kilometers peak to peak). If North America, Australia, and other continents were dynamically depressed by the one to two kilometers predicted, then these continents would today be below sea level and nearly covered by epeiric seas. Since the continents are nearly entirely exposed and have become progressively exposed since the Late Mesozoic the amplitude of the Forte et al., model is clearly much too large.