Almost all of the breakthroughs in understanding the ocean have been initiated by observations, using a range of instrumental techniques. Nowadays, satellite application is a good answer to the common requirement of meteorology and oceanography for comprehensive information on the ocean and atmosphere. Many different instruments have been installed on earth observation satellites. Among them the synthetic aperture radar (SAR) is the only instrument which up to now can provide high-resolution, two dimensional sea surface information on a global scale. Written as a comprehensive introduction to the techniques of SAR application into ocean for the oceanographic scientist, research student or undergraduate. It focuses on the systematic validation and comparison of met-ocean parameters like significant wave height, wind speed and mean wave period obtained from ERS SAR image using empirical algorithms, in situ and satellite observations, reanalysis and model results.