Entropy of sea wave height field and its annual variation in Northwest Pacific Ocean

A kind of entropy is defined by the statistical distribution of observed wave heights of a sea surface during a specified period and calculated from the wave height data of Northwest Pacific Ocean (NWPO) given by GEOSAT altimeter. The results obtained show that there is an annual variation of the entropy with the peak of its value in winter and the trough in summer. In consideration of the fact that the roughness and the wind stress of sea surface are connetted with wave heights, it is expected that the present results might have some potential applications in the research on large scale atmosphere and ocean dynamics.