An integrated marine data collection for the German Bight – Part 1: Subaqueous geomorphology and surface sedimentology (1996–2016)

Abstract

Abstract. The German Bight located within the central North Sea is a hydro- and morphodynamically highly complex system of estuaries, barrier islands, and part of the world's largest coherent tidal flats, the Wadden Sea. To identify and understand challenges faced by coastal stakeholders, such as harbor operators or governmental agencies, to maintain waterways and employ numerical models for further analyses, it is imperative to have a consistent database for both bathymetry and surface sedimentology. Current commercial and public data products are insufficient in spatial and temporal resolution and coverage for recent analysis methods. Thus, this first part of a two-part publication series of the German joint project EasyGSH-DB describes annual bathymetric digital terrain models at a 10 m gridded resolution for the German North Sea coast and German Bight from 1996 to 2016 (Sievers et al., 2020a, https://doi.org/10.48437/02.2020.K2.7000.0001), as well as surface sedimentological models of discretized cumulative grain size distribution functions for 1996, 2006, and 2016 on 100 m grids (Sievers et al., 2020b, https://doi.org/10.48437/02.2020.K2.7000.0005). Furthermore, basic morphodynamic and sedimentological processing analyses, such as the estimation of, for example, bathymetric stability or surface maps of sedimentological parameters, are provided (Sievers et al., 2020a, b, see respective download links).

Exploring the Tidal Response to Bathymetry Evolution and Present-Day Sea Level Rise in a Channel-Shoal Environment

“…The computational grid consists of approximately 202,000 horizontal unstructured cells, more than 10,000,000 refining subgrid cells, and 54 vertical z-layers with a minimum height of Bathymetry Consortium, 2018). Inside of the focus area, 10 m bathymetry grids were merged from a multitude of observational surveys with different measurement technique, frequency, and accuracy using a specialized interpolation algorithm in time and space (Sievers et al, 2020;Sievers et al, 2021). Model validation for the year 2015 corresponded to observations with an average RMSE of 10.6 cm in high water, 13.3 cm in tidal range, and 17.6 minutes in flood duration (Hagen et al, 2021).…”

Exploring the tidal response to bathymetry evolution and present-day sea level rise in a channel–shoal environment

“…1b) was interpolated from the Dutch Vaklodingen dataset and the European Marine Observation and Data Network (EMODnet) digital terrain model (EMODnet Bathymetry Consortium, 2018). Inside the focus area, 10 m bathymetry grids were merged from a multitude of observational surveys with different measurement techniques, frequencies, and accuracies using a specialized interpolation algorithm in time and space (Sievers et al, 2020(Sievers et al, , 2021. Model validation for the year 2015 corresponded to observations with an average RMSE of 10.6 cm in high water, 13.3 cm in tidal range, and 17.6 min in flood duration (Hagen et al, 2021).…”

A cross-border mud budget for future sediment management

“…We use Dutch bathymetry data of the Vaklodingen dataset (resolution of 20 × 20 m) [39] and German data collected within the EASY-GSH project (resolution of 10 × 10 m) [40,44]. Sediment composition information is based on the Sedimentatlas (Netherlands parts of the Wadden Sea, resolution of 500 × 500 m in the channels, and 1000 × 1000 m on the intertidal flats) [41], SIBES (Netherlands parts of the Wadden Sea, resolution of 1000 × 1000 m in the channels, and 500 × 500 m on the intertidal flats) [42,43] and EASY-GSH datasets (German parts of the Wadden Sea, based on 45000 surface sediment samples which are interpolated on a 10 × 10 m grid) [44].…”

“…Transport of mud cannot be predicted with empirical formulae because its transport is supply-limited, and therefore needs to be based on observed bathymetric changes or detailed measurements of hydrodynamics and sediment concentrations. The Wadden Sea provides herein a globally unique case, with detailed observations of bathymetric changes and grain size distribution [39][40][41][42][43][44][45]. Such observations can be used to quantify the contribution of sand and mud to infilling [46], thereby providing a sediment budget.…”