Satellite altimeter data in wave energy studies

Measurements from the GEOSAT, ERS-1 and 2 and Topex/Poseidon satellites have now accumulated over 15 years of global wave and wind data. Extraction of wave height, wind speed and wave period from the altimeters is discussed and currently used algorithms are given. The Topex altimeter has been found to be significantly more accurate at all wave heights than the other satellites and the data are also more reliable. There is still a need for a closer look at correction algorithms, in particular to improve the accuracy at higher wave heights and wind speeds as currently used algorithms appear to give rather conservative extreme conditions. The application of satellite remote sensing data is illustrated in five different wave energy resource studies in the South Pacific, Philippines, Indonesia, Europe and a global study. In the latter study, satellite data have been used for the first rime to map the wave energy resource along practically all the world coastlines. These examples serve to illustrate the many different ways of using satellite altimeter data even within such a narrow application area.