Estimation of extreme wave height return periods from short-term interpolation of multi-mission satellite data: Application to the South Atlantic

Abstract

We analyzed the spatial pattern of wave extremes in the South Atlantic Ocean by using multiple altimeter platforms spanning the period 1993-2015. Unlike the traditional approach adopted by previous studies, consisting of computing the monthly mean, median or maximum values inside a bin of certain size, we tackled the problem with a different procedure in order to capture more information from short-term events. All satellite tracks occurring during a 2-day temporal window were gathered in the whole area and then gridded data were generated onto a mesh size of 2° × 2° through optimal interpolation. The peaks over threshold (POT) method was applied, along with the generalized Pareto distribution (GPD). The results showed a spatial distribution comparable to previous studies and, additionally, this method allowed for capturing more information on shorter timescales without compromising spatial coverage. A comparison with buoy observations demonstrated that this approach improves the representativeness of short-term events in an extreme events analysis.