On estimating extreme wave heights using combined Geosat, Topex/Poseidon and ERS-1 altimeter data

The estimation of extreme significant wave heights H-s using altimeter observations is investigated. Data from the following three satellite missions are used: Geosat, ERS-1 and Topex/Poseidon. Practical methods of estimating extreme H-s are described and limitations of their application to altimeter data are highlighted. Extreme H-s are estimated using the three-parameter Weibull distribution, with maxima selected via the peaks over threshold method, and the Fisher-Tippet type I distribution, using data selected via the initial distribution method. Altimeter estimates are compared to extreme H-s calculated from deep water buoy data. A comparative analysis of global estimates of satellite-derived extreme H-s based on standard statistics investigates time-space undersampling and how it affects the reliability of long-term extreme wave estimates made using satellite altimeter data. (C) 2004 Elsevier Ltd. All rights reserved.