Morphological Responses of Pingshuiqiao Beach to a Major Storm Based on Computer Vision

Abstract:

In order to study the response process of storm surge on the beach， video monitoring and computer vision were used to obtain color images of the beach through several cameras set up on the shore high place. The improved Canny algorithm combined with dual threshold processing was used to automatically extract the shoreline. Used camera calibration to obtain the geographic coordinates of the shoreline. The multi-temporal shorelines were interpolated to obtain the shoreline coordinates and beach topography. Through continuous monitoring and analysis， it was found that Pingshuiqiao beach in Qinhuangdao responded sharply to the storm surge process in a short time. Sediment was transported westward and toward the sea， the beach berm suffered obviously erosion and sand was coarsened. This caused the intertidal siltation， the beach slope decrease， and the coastline advancing 4.34 m toward the sea. In the recovery period after the storm surge， the high tide zone of Pingshuiqiao beach headland shield section was slightly eroded and silted in the middle and low tide zone， and the sediment was transported offshore. The evolution of the straight section is mainly affected by the small and medium recovery waves， which show the trend of upper siltation and lower erosion， and the sediment was transported from the middle and low tide zone to the high tide zone.

Key words:computer vision;video monitoring;hydrodynamic model;storm surge