A unifying framework for shoreline migration: 2. Application to wave-dominated coasts
Journal Article (Journal Article)
The Bruun rule, widely used to predict transgression due to sea level rise on decade to century timescales based on a fixed nearshore profile, neglects the influence of inland topography and substrate lithology, leading to physically unreasonable predictions on longer timescales. We use a new approach, the shoreline Exner equation, to model shoreline transgression on wave-dominated coasts over timescales of decades to millennia. Our results show that interactions between nearshore processes and inland topography, neglected by Bruun-style models, drive morphologic evolution which modulates shoreline retreat. Analytical solutions suggest that while short-term shoreline retreat will sometimes follow the Bruun rule, long-term transgression will always follow the slope of the inland topography. Moreover, our results show that the slope of the inland landscape, relative to the nearshore slope, exerts a first-order control on coastal morphology, such that steep coasts tend to form cliff-backed beaches while gentle coasts tend to form barrier island-lagoon systems. However compositional variations between the inland landscape and nearshore system can alter this pattern. Copyright 2009 by the American Geophysical Union.
Full Text
Duke Authors
Cited Authors
- Wolinsky, MA; Brad Murray, A
Published Date
- March 1, 2009
Published In
Volume / Issue
- 114 / 1
Electronic International Standard Serial Number (EISSN)
- 2169-9011
Digital Object Identifier (DOI)
- 10.1029/2007JF000856
Citation Source
- Scopus