Spatial Frequency Analysis and Information Synthesis for Understanding Coastal Barriers

Abstract

Coastal systems are inherently variable alongshore, particularly sandy-beach systems along barrier coasts. Variability in the beach and dune influences the response and recovery of coastal barriers to storm activity, which in turn influences the evolution of these systems with rising sea levels and a change in storm activity. Characterizing this variability provides important insights on how the system has evolved over a wide range of timescales, and it can be used to predict how the system may evolve in the future. This article reviews scale-dependent topographic variations in sandy beach environments, and the field and spatial analytical methods used to characterize alongshore variability in beach and dune morphology, over a wide range of spatial and temporal scales, in response to both free (self-reinforcing) storm and anthropogenic perturbations and forced by a framework geology. Across all spatiotemporal scales, the alongshore variability in beach and dune morphology influences the response and recovery of barrier islands to storm activity, and thereby provides important insights about the evolution of that system. This article examines the various analytical approaches used to characterize the alongshore variability of barrier environments, the methods used to extract coastal morphology from digital elevation models, the opportunities for multi-sensor integration and how machine learning provides an opportunity to characterize this variability and identify scale-dependent controls.