Surface cobble observations at Torrey Pines State Beach, California

Hironori Matsumoto, University of California San Diego, Scripps Institution of Oceanography, La Jolla, CA, United States, Adam Young, University of California San Diego, Scripps Institution of Oceanography, La Jolla, United States and Robert T Guza, Scripps Institution of Oceanography, La Jolla, CA, United States
Abstract:
Composite beaches consisting of a cobble upper foreshore and a sandy lower foreshore are relatively unstudied. We describe spatially and temporarily varying surface cobble exposure over a ~2.2km alongshore span at Torrey Pines State Beach, a composite beach with sometimes transient beach face cobble patches and backshore cobble berms. Subaerial surface cobble exposure was mapped using ground-based mobile LiDAR surveys and a machine learning algorithm. Surface cobble exposure is seasonal and decreases in summer when the subaerial beach is accreted. In winter, cobble exposure substantially increases and backshore cobble morphology changes 3-dimensionally. This study describes unique temporal patterns, rates of surface cobble exposure, and morphological changes, and provides insight of composite beaches dynamics. This research was supported by California Department of Parks and Recreation, and the U.S. Army Corps of Engineers.
Back to: Close-Range Remote Sensing of Nearshore Processes and Coastal Morphology II