Preliminary Model Results of Beach Profile Dynamics with Stratigraphy

Tuesday, 16 December 2014
Adrianus J Reniers1, Melike Koktas2, Edith L Gallagher3, Heidi M Wadman4, Katherine L Brodie5, Bradley D Johnson4 and Jesse McNinch6, (1)Delft University of Technology, Hydrolic Engineering, Delft, 5612, Netherlands, (2)Delft University of Technology, Hydrolic Engineering, Delft, Netherlands, (3)Franklin & Marshall College, Lancaster, PA, United States, (4)USACE-ERDC Information Technology Laboratory, Vicksburg, MS, United States, (5)US Army Corps of Engineers, Jacksonville, FL, United States, (6)US Army Corps of Engineers, Field Research Facility, Kitty Hawk, NC, United States
The presence of spatial variation in grain size within the surf and swash zone is often ignored in numerical modeling whereas Upon closer inspection, a broad range of grain sizes is visible on a beach. This could potentially lead to a significant mismatch between predictions and observations of profile evolution given the strong sensitivity of sediment transport formulae to the grain size. To explore this in more detail, numerical simulations with XBeach have been performed to simulate the observations of changes in beach profile and stratigraphy within the swash zone at Duck, NC, under a range of wave and tidal conditions (see presentations by Wadman et al., and Gallagher et al. for complementary information on the observations at this conference). The research focus is to establish the morphodynamic response to the sediment dynamics at short and longer time scales in the presence of stratigraphy. A better understanding of the mechanisms and subsequently improved modeling will provide more accurate predictions of the morphodynamic response of the beach during moderate and extreme conditions. It will also help in the interpretation of sediment layering of the beach to relate to past extreme storms on geological time scales.