Using Video Imagery to Study Coastal Change: Whidbey Island

Science Center Objects

From May of 2018 through November of 2019, USGS scientists collected imagery from video cameras overlooking the coast along a beach on Whidbey Island, Island County at the northern boundary of Puget Sound in western Washington.

    Wet sand on a beach has a little shallow water with rocks and boulders, coastal cliffs in background.

    View of beach on Whidbey Island, looking north.

    The study area has some of the highest rates of coastal bluff retreat in Puget Sound. In fact, towards the end of 2019, the cliff area where the cameras were installed showed signs of failure, so the cameras were removed.

    An interagency team led by the USGS is researching how extreme-storm water levels and waves affect bluff erosion and the movement of sediment along beaches. The video-based remote-sensing tools measured storm water levels, waves, currents, and beach, and bluff changes to property, infrastructure, and habitats. The data enabled scientists to examine sediment transport that affects habitats for valued juvenile salmon, forage fish, and shellfish. In particular, the research is evaluating the extent that waves and sediment modify habitat complexity and its role in wave runup as well as shellfish biomass and diversity. Ultimately, the research will help guide and improve numerical model predictions of coastal and habitat change associated with sea-level rise, storms, and waves to inform resilience planning.

    On a high coastal cliff, a video camera is mounted on a pole and secured to a tree, and down below it's low tide.

    The video cameras are secured to a tree.

    USGS projects that will benefit from this study include:

     

     

    Every half hour during daylight hours, from May of 2018 through November of 2019, video cameras installed on the high coastal bluff collected snapshots and video for 10 minutes. Some examples of the imagery are shown here.

    View from up high above a flat beach area lots of rocks and boulders, very little wave action.

    Snapshot: the first frame of the video, just like a standard photo.

    View looks down at a rocky beach at low tide, from up high on cliff.

    Timex (time-exposure) image: a time-averaged image of all frames, smoothing away surface waves and determining the location of persistent wave-breaking (indicative of shallow sandbars).

     

    View of a beach from up high on a cliff, with some boulders and rocky areas visible during low tide.

    Bright image: the brightest pixel values throughout the video, useful for identifying the position of maximum wave run-up on the beach, position of all breaking waves, and sea-state.

    View of a beach from up high on a cliff, with some boulders and rocky areas visible during low tide.

    Dark image: the darkest pixel values throughout the video, useful for tracking sediment plumes, tracking floating debris, and filtering out breaking waves.

     

    View looking down at a rocky beach at low tide, from up high on a cliff.

    Variance image: the standard deviation of pixel intensity throughout the video, and it is useful for determining how much variation or movement is occurring at a given location.