See more from this Division: Topical Sessions
See more from this Session: The Mississippi River Delta as a Natural Laboratory for Evaluating Coastal Response to Relative Sea-Level Rise and Innovations in Transgressive Coastal Management: Shea Penland Memorial Session
Abstract:
Reanalysis of the Dingler and Reiss data set indicates average erosion of the subaerial beach above Mean Sea Level (MSL) equal to -67 cu m/m/yr, whereas the sub-aqueous portion of the profile (above-1.25 m MSL) increased by 22 cu m/m/yr. The deficit of 45 cu m/m/yr most likely represents loss of fine sediment from the littoral system. The percentage of this loss (~67%) is approximately equal to the percentage of fines (69%) estimated by List et al. (1997) based on sediment core data for non-reworked deltaic sediment.
These data also provide quantification of non-storm processes. Prior to Hurricane Andrew, from 1986 through 1991, the dune crest was increasing in elevation at 9.2 cm/m/yr presumably through minor overwash events and eolian transport. Andrew flattened the dune and exposed the cohesive substrate. Following Andrew, the exposed cohesive substrate eroded from Nov 1992 to Nov 1993 at a rate of -16.8 cu m/m/yr while the remainder of the profile was stable, indicating only minor storms occurred during this period. These data are being applied to test a conceptual model of non-storm erosion and post-storm recovery for barrier islands.
See more from this Division: Topical Sessions
See more from this Session: The Mississippi River Delta as a Natural Laboratory for Evaluating Coastal Response to Relative Sea-Level Rise and Innovations in Transgressive Coastal Management: Shea Penland Memorial Session