Robust methods for the decomposition and interpretation of compound dunes applied to a complex hydromorphological setting

Research output: Contribution to journalArticleResearchpeer review

Authors

  • Leon Scheiber
  • Oliver Lojek
  • Axel Götschenberg
  • Jan Visscher
  • Torsten Schlurmann

External Research Organisations

  • Federal Waterways and Shipping Administration (WSV)
View graph of relations

Details

Original languageEnglish
Pages (from-to)478-489
Number of pages12
JournalEarth Surface Processes and Landforms
Volume46
Issue number2
Early online date28 Nov 2020
Publication statusPublished - 9 Feb 2021

Abstract

Underwater dunes are a morphological feature that are explored by marine scientists and coastal engineers alike. This study presents new methodologies in order to simplify bedform identification and morphodynamic analyses. Specifically, subaqueous compound dunes are decomposed with a simple yet extensive tracking algorithm, which relies on a repeated evaluation of unfiltered bed elevation profiles according to five predefined length classes. In a second step, morphological trends are assessed in the form of bed migration rates, bed slope asymmetries and net sediment changes, in which all parameters are referred to equidistant sections of the examined fairway stretch. This integrated approach not only avoids the challenges in weighting the varying size and abundance of dunes of different scales but also ensures comparability between dune-specific and areal parameters, which significantly improves the interpretation of the morphological setting as a whole. The developed methods are applied to the Outer Jade fairway, an anthropogenically influenced and regularly maintained waterway in the German Bight, and allow scrutiny of spatio-temporal trends in this region. Based on a unique data set of 100 sequential high-quality echo-sounding surveys, various types of bedforms are identified, comprising large-scale primary as well as superimposing secondary dunes that are assumed to interfere with each other. Temporal trends show a long-term rise of the troughs of major bedforms and constant maximum crest elevations near the official maintenance depth, which matches the observed long-term aggradation of sediments. The spatial distribution of integrated morphodynamic parameters reflects a previously described zone of primary dune convergence and facilitates the precise localization of this geophysical singularity. The presented findings both confirm the robustness of the proposed methodologies and, in return, enhance the understanding of morphological processes in the Outer Jade.

Keywords

    German North Sea, Jade fairway, bedform identification, morphodynamics, subaqueous compound dunes

ASJC Scopus subject areas

Sustainable Development Goals

Cite this

Robust methods for the decomposition and interpretation of compound dunes applied to a complex hydromorphological setting. / Scheiber, Leon; Lojek, Oliver; Götschenberg, Axel et al.
In: Earth Surface Processes and Landforms, Vol. 46, No. 2, 09.02.2021, p. 478-489.

Research output: Contribution to journalArticleResearchpeer review

Scheiber L, Lojek O, Götschenberg A, Visscher J, Schlurmann T. Robust methods for the decomposition and interpretation of compound dunes applied to a complex hydromorphological setting. Earth Surface Processes and Landforms. 2021 Feb 9;46(2):478-489. Epub 2020 Nov 28. doi: 10.1002/esp.5040
Download
@article{209a6daad6e9412fae96485a5a252f7a,
title = "Robust methods for the decomposition and interpretation of compound dunes applied to a complex hydromorphological setting",
abstract = "Underwater dunes are a morphological feature that are explored by marine scientists and coastal engineers alike. This study presents new methodologies in order to simplify bedform identification and morphodynamic analyses. Specifically, subaqueous compound dunes are decomposed with a simple yet extensive tracking algorithm, which relies on a repeated evaluation of unfiltered bed elevation profiles according to five predefined length classes. In a second step, morphological trends are assessed in the form of bed migration rates, bed slope asymmetries and net sediment changes, in which all parameters are referred to equidistant sections of the examined fairway stretch. This integrated approach not only avoids the challenges in weighting the varying size and abundance of dunes of different scales but also ensures comparability between dune-specific and areal parameters, which significantly improves the interpretation of the morphological setting as a whole. The developed methods are applied to the Outer Jade fairway, an anthropogenically influenced and regularly maintained waterway in the German Bight, and allow scrutiny of spatio-temporal trends in this region. Based on a unique data set of 100 sequential high-quality echo-sounding surveys, various types of bedforms are identified, comprising large-scale primary as well as superimposing secondary dunes that are assumed to interfere with each other. Temporal trends show a long-term rise of the troughs of major bedforms and constant maximum crest elevations near the official maintenance depth, which matches the observed long-term aggradation of sediments. The spatial distribution of integrated morphodynamic parameters reflects a previously described zone of primary dune convergence and facilitates the precise localization of this geophysical singularity. The presented findings both confirm the robustness of the proposed methodologies and, in return, enhance the understanding of morphological processes in the Outer Jade.",
keywords = "German North Sea, Jade fairway, bedform identification, morphodynamics, subaqueous compound dunes",
author = "Leon Scheiber and Oliver Lojek and Axel G{\"o}tschenberg and Jan Visscher and Torsten Schlurmann",
year = "2021",
month = feb,
day = "9",
doi = "10.1002/esp.5040",
language = "English",
volume = "46",
pages = "478--489",
journal = "Earth Surface Processes and Landforms",
issn = "0197-9337",
publisher = "John Wiley and Sons Ltd",
number = "2",

}

Download

TY - JOUR

T1 - Robust methods for the decomposition and interpretation of compound dunes applied to a complex hydromorphological setting

AU - Scheiber, Leon

AU - Lojek, Oliver

AU - Götschenberg, Axel

AU - Visscher, Jan

AU - Schlurmann, Torsten

PY - 2021/2/9

Y1 - 2021/2/9

N2 - Underwater dunes are a morphological feature that are explored by marine scientists and coastal engineers alike. This study presents new methodologies in order to simplify bedform identification and morphodynamic analyses. Specifically, subaqueous compound dunes are decomposed with a simple yet extensive tracking algorithm, which relies on a repeated evaluation of unfiltered bed elevation profiles according to five predefined length classes. In a second step, morphological trends are assessed in the form of bed migration rates, bed slope asymmetries and net sediment changes, in which all parameters are referred to equidistant sections of the examined fairway stretch. This integrated approach not only avoids the challenges in weighting the varying size and abundance of dunes of different scales but also ensures comparability between dune-specific and areal parameters, which significantly improves the interpretation of the morphological setting as a whole. The developed methods are applied to the Outer Jade fairway, an anthropogenically influenced and regularly maintained waterway in the German Bight, and allow scrutiny of spatio-temporal trends in this region. Based on a unique data set of 100 sequential high-quality echo-sounding surveys, various types of bedforms are identified, comprising large-scale primary as well as superimposing secondary dunes that are assumed to interfere with each other. Temporal trends show a long-term rise of the troughs of major bedforms and constant maximum crest elevations near the official maintenance depth, which matches the observed long-term aggradation of sediments. The spatial distribution of integrated morphodynamic parameters reflects a previously described zone of primary dune convergence and facilitates the precise localization of this geophysical singularity. The presented findings both confirm the robustness of the proposed methodologies and, in return, enhance the understanding of morphological processes in the Outer Jade.

AB - Underwater dunes are a morphological feature that are explored by marine scientists and coastal engineers alike. This study presents new methodologies in order to simplify bedform identification and morphodynamic analyses. Specifically, subaqueous compound dunes are decomposed with a simple yet extensive tracking algorithm, which relies on a repeated evaluation of unfiltered bed elevation profiles according to five predefined length classes. In a second step, morphological trends are assessed in the form of bed migration rates, bed slope asymmetries and net sediment changes, in which all parameters are referred to equidistant sections of the examined fairway stretch. This integrated approach not only avoids the challenges in weighting the varying size and abundance of dunes of different scales but also ensures comparability between dune-specific and areal parameters, which significantly improves the interpretation of the morphological setting as a whole. The developed methods are applied to the Outer Jade fairway, an anthropogenically influenced and regularly maintained waterway in the German Bight, and allow scrutiny of spatio-temporal trends in this region. Based on a unique data set of 100 sequential high-quality echo-sounding surveys, various types of bedforms are identified, comprising large-scale primary as well as superimposing secondary dunes that are assumed to interfere with each other. Temporal trends show a long-term rise of the troughs of major bedforms and constant maximum crest elevations near the official maintenance depth, which matches the observed long-term aggradation of sediments. The spatial distribution of integrated morphodynamic parameters reflects a previously described zone of primary dune convergence and facilitates the precise localization of this geophysical singularity. The presented findings both confirm the robustness of the proposed methodologies and, in return, enhance the understanding of morphological processes in the Outer Jade.

KW - German North Sea

KW - Jade fairway

KW - bedform identification

KW - morphodynamics

KW - subaqueous compound dunes

UR - http://www.scopus.com/inward/record.url?scp=85100037139&partnerID=8YFLogxK

U2 - 10.1002/esp.5040

DO - 10.1002/esp.5040

M3 - Article

VL - 46

SP - 478

EP - 489

JO - Earth Surface Processes and Landforms

JF - Earth Surface Processes and Landforms

SN - 0197-9337

IS - 2

ER -