ABSTRACT

Mid-latitude Rossby waves substantiated in the upper tropospheric (300-200 hPa) potential vorticity field exert rather significant influences on the ocean surface conditions.

Detailed analysis shows quantitatively that the passing of positive Rossby waves with cyclonic vortex increases net shortwave and longwave radiations over the ocean surface by promoting a clearer sky condition. Further, reduced humidity and temperature above the sea surface increase latent and sensible heat fluxes. The increased latent and sensible heat fluxes, in turn, induce secondary atmospheric circulation characterized by anticyclonic and divergent motion in the lower atmospheric layer above the sea surface.

Although the increased latent and sensible heat fluxes may change sea surface temperatures, the complexity of ocean dynamics with complicated land-ocean configurations and the mismatch of the temporal and spatial scales of atmospheric and oceanic motions smears the footprint of Rossby waves. Dynamical and thermodynamical dissimilarity between the maritime and the continental responses to Rossby waves is substantial.