This repository contains the data described in Vos, K., Harley, M. D., Splinter, K. D., Walker, A., & Turner, I. L. (2020). Beach Slopes From Satellite‐Derived Shorelines. Geophysical Research Letters, 47(14), e2020GL088365. There are 2 GEOJSON files in this repository. The coordinate system for both geospatial layers is WGS84 (epsg:4326). 1. slopes_along_transects.geojson: contains a geospatial layer with cross-shore transects for sandy coastlines along SE Australia and California. Each feature in this layer is a transect (2 point linestring) with the following attributes: - site_id: id of the beach in which the transect is located - id: id of the individual transect - orientation: orientation of the transect in degrees from North (positive clockwise) - beach slope: beach-face slope from Mean Sea Level (MSL) to Mean High Water Springs (MHWS) 2. slopes_along_beaches.geojson: this layer contains sandy beaches instead of transects. For each beach the median slope has been calculated from all the available transects. The following attributes are available: - id: id of the beach - name: name of the beach in the OpenStreetMap database (if not available 'noname') - beach_length: length of the beach in metres - median_orientation: beach orientation calculated as the median of the orientations of each transect - Tide range: average tidal range (mean high water - mean low water) at each beach based on FES2014 global tide model - median_slope: median beach-face slope along the beach based on the estimated beach-face slope along the transects