Data to Support Analyses of Shoreline Seasonal Cycles for Beaches of California

Coastal shorelines commonly have recurring patterns of retreat and recovery that are related to annual patterns in wave climate. To assist with investigations of these seasonal cycles, we have analyzed shoreline position and wave data for the beaches of California to generate a series of metrics that describe the magnitude and timing of seasonal patterns of the shoreline and offshore wave climate. These data should be useful for science researchers, students, policy makers, and the public. The data can be used with geographic information systems or other software to help identify characteristics and patterns in California’s shoreline.

The seasonal cycles in California’s shoreline were derived from time-series analyses of shoreline position data from the CoastSat technique (Vos, 2023). The analyses used to describe seasonal cycles include Seasonal Trend decomposition with LOESS (STL; Cleveland and others, 1990), spectral analyses, and unsupervised clustering. These techniques were applied to 7777 transects from California’s beaches that captured shoreline patterns during 2000-2022. In addition to these shoreline seasonality metrics, we also provide several geographic metrics, including location, shoreline orientation, beach slope, back-beach location, and beach width for each transect.

In addition, we provide synthesis data of the offshore wave conditions for sites directly offshore of the 7777 beach transects. Monthly wave characteristics were derived from the 2000-2022 data provided by the Coastal Data Information Program [CDIP, https://cdip.ucsd.edu] hindcast analysis.

References Cited
Cleveland R.B., Cleveland W.S., McRae J.E., Terpenning I., 1990, STL: A seasonal-trend decomposition procedure based on loess. Journal of Official Statistics, 6:3–73

Vos, K., 2023, Time-series of shoreline change along the Pacific Rim (v1.4) [Data set]. Zenodo, doi: 10.5281/zenodo.7758183