Solar irradiance (insolation) at the sea surface has become to be more commonly estimated by wide-coverage (in both spatially and temporally) visible imagery data obtained from operational geostationary satellites and/or polar-orbiters. In this article, the basic idea of the technique is reviewed along with several major constituents of the methodology. Then the method's superiority to conventional empirical estimation and some known problems and limitations are discussed. Finally, some examples of the oceanographic application are briefly described.
