Section 11: Select Application Topographic Variation Of Barrier Island Subenvironments And Associated Habitats

Brief overview of shoreline types, bays vs. Gulf Brief overview of shoreline types, bays vs. Gulf. Shoreline monitoring is challenging because of the length of shoreline and variety of shoreline types.

Study Site Bay Tide Range= 0.11 m Gulf Tide Range= 0.5 m Gulf Wave Height= 0.9 m Bay Tide Range= 0.11 m Bay Wave Heights < 0.5 m

Color IR Mosaic

Barrier Island Environments

Habitat Classification Map From Color Ir Photography

1-m Digital Elevation Model

Average Heights and Standard Deviations Of Barrier Island Habitats

1-m Digital Elevation Model

Ground and Lidar Profiles

View Bayward along Transect

Habitat Change Since 1950’s

Current Sea Level

Sea Level Plus 0.2 meters

Conclusions Detailed and accurate lidar DEM’s may serve as a truly independent and physically meaningful data layer for mapping barrier island habitats in conjunction with other data types such as multispectral or radar imagery. Vegetation causes scatter in the lidar point data and biases the data to be above the substrate. Full wave-form digitization of the reflected laser pulse is one way being pursued to lessen the vegetation effect. Lidar DEM’s can help predict the change in habitats during particular sea-level-rise scenarios. In barrier island settings along the Texas coast, a relative sea-level rise of just 0.2 m will have a profound effect on the distribution of wetland habitats. Based on tide gauge records since the 1950’s, this amount of sea-level rise is expected to occur during the next 55 years.