EXTRACTING MORPHOLOGIC INFORMATION FROM FIELD DATA

Abstract

We quantified the strengths and weaknesses of two sources of morphologic data available from Duck, NC, utilizing an objective definition of nearshore morphology (Gaussian curves added to a plane slope). Directly surveyed bathymetry provided the most complete estimate of the morphologic state of the nearshore bathymetry. That is, all of the parameters of the morphologic model could be estimated from these data. Oblique video images were used to estimate the position of inner bars. This information represented only a subset of the morphologic parameters defined in the morphologic model. However, the image data were collected frequently (daily) and, thus, resolved a wide range of temporal scales. Bar crest positions estimated from the video images were well correlated with estimates extracted from the bathymetric surveys (R2 = 0.8). Differences between the two estimates of bar position depended on both wave height and on the bar amplitude.