CoAuthors

Victoria Grigorieva (P.P. Shirshov Institute of Oceanology, Russia); Alexander Gavrikov (P.P. Shirshov Institute of Oceanology, Russia); Lotfi Aouf (Division Marine et Océanographie Météo-France - DPREVI/MAR, France)

A new approach to processing data of satellite altimetry is proposed. Sea wave steepness is estimated from variations of the measured wave heights along the satellite track. The resulting formula resembles the well-known relationship of geostrophic balance between variations of sea surface height and a component of large-scale (geostrophic) current and does not contain empirical parameters. A distinctive feature of the formula is its inherent nonlinearity. On one hand, it makes the method quite selective in wave length and steepness. On the other hand, the nonlinearity reduces essentially the effects both of data noise and of a priori unknown wave direction.

Relevance of the new method to the data quality of altimeter missions ENVISAT, Jason-1,2 and Saral/AltiKa is demonstrated for global distributions of wind wave parameters and in case studies for the Caspian Sea, the US East nearshore and the Great Australian Bight.