2022 CSDMS meeting-047
Multiscale analysis of shoreline structure to classify river deltas
Lawrence Vulis, (he/him),University of California Irvine Irvine California, United States. firstname.lastname@example.org
Alejandro Tejedor, Sorbonne University Abu Dhabi Abu Dhabi , United Arab Emirates.
Hongbo Ma, University of California Irvine Irvine California, United States.
Jaap Nienhuis, Utrecht University Utrecht , Netherlands.
Connor Broaddus, University of California Irvine Irvine California, United States.
Jack Brown, University of California Irvine Irvine California, United States.
Doug Edmonds, Indiana University Bloomington Indiana, United States.
Joel C. Rowland, Los Alamos National Laboratory Los Alamos New Mexico, United States.
Efi Foufoula-Georgiou, University of California Irvine Irvine California, United States.
Delta shoreline structure has long been hypothesized to encode information on the relative influence of fluvial, wave, and tidal processes on delta formation and evolution. However analyses and comparisons of deltaic shorelines have typically been qualitative or utilized relatively coarse quantitative metrics. We ask whether robust quantification of shoreline structure would enable mapping of deltas to a physically-based space in which the relative influence of the different processes could be compared, as has recently been done using a sediment flux budget approach. To explore this question, we analyze Landsat-derived shorelines from more than 50 deltas across the globe. Since the shorelines exhibit variability on scales ranging from tens of meters to tens of kilometers, we propose a multiscale characterization of shoreline structure by mapping the shorelines to a univariate series, through a macro-scale convexity-informed framework, and using localized multi-resolution analysis via wavelets to quantify shoreline variability across a range of spatial scales within and across deltas. Specifically, we focus on the relative energy contributed by meso-scale features (river mouths) and small-scale (less than 1 km scale features). We find that distinct classes of deltas naturally emerge in that metric space, which we attribute to the different processes driving the sources and sinks of sediment in these systems. The analysis suggests the potential towards a quantitative, process-based classification of delta morphology via multi-scale analysis of shoreline structure.