Mass and Energy Transports in an Undisturbed Atlantic Trade-Wind Flow

Abstract

The vertical and horizontal mass and energy transports for the layer between the sea surface and 700 mb are calculated for the first (undisturbed) period of the Atlantic Trade-Wind Experiment 1969. The trade-wind inversion represents a layer with a strong downward mass flux due to the mean motion. The height of the inversion and its thermodynamic properties seem to depend on the balance between the mean atmospheric sinking and the turbulent mixing. Because of the vertical transport from the sea surface into the atmosphere, this process assures that water vapor is totally accumulated in the layer below the inversion and transported downstream into the equatorial trough region. Thus the effectiveness of the atmospheric heat absorption in the trades as a force for driving the large-scale circulation is closely related to the vertical static structure as well as to the kinematic field of the low-level trade-wind region.