2022 CSDMS meeting-037
Event Severity vs Frequency for a Patch of Seabed using Extreme Value Analysis (EVA)
The observational dataset for the study is a large, publicly available compilation of 3-decades of annual, hydrographic-standard bathymetric soundings in the German Bight, provided in gridded form at a spatial resolution of 50m. Counts of annual seabed elevation changes by elapsed time were compiled and related to the seabed features, such as tidal channels (which have previously been well studied).
The change statistics were compared to forms of the Generalized Extreme Value and Generalized Pareto distributions, per pixel and also by small morphodynamically uniform subareas. The Generalized Pareto distribution with coefficient c ≈ -6.0 to -6.5 appears to be the appropriate model, but adjusted according to water depths and locations on features.The result suggests a method to statistically model seabed behavior including extreme events.