Rovere, Alessio; Casella, Elisa; Harris, Daniel L; Lorscheid, Thomas; Nandasena, Napayalage A K; Dyer, Blake; Sandstrom, Michael R; Stocchi, Paolo; D'Andrea, William J; Raymo, Maureen E (2017): Wave models for Eleuthera, Northern Bahamas. PANGAEA, https://doi.org/10.1594/PANGAEA.880687, Supplement to: Rovere, A et al. (2017): Giant boulders and Last Interglacial storm intensity in the North Atlantic. Proceedings of the National Academy of Sciences, 114(46), 12144-12149, https://doi.org/10.1073/pnas.1712433114
Always quote citation above when using data! You can download the citation in several formats below.
As global climate warms and sea level rises, coastal areas will be subject to more frequent extreme flooding and hurricanes. Geologic evidence for extreme coastal storms during past warm periods has the potential to provide fundamental insights into their future intensity. Recent studies argue that during the Last Interglacial (MIS 5e, ~128-116 ka) tropical and extratropical North Atlantic cyclones may have been more intense than at present, and may have produced waves larger than those observed historically. Such strong swells are inferred to have created a number of geologic features that can be observed today along the coastlines of Bermuda and the Bahamas. In this paper, we investigate the most iconic among these features: massive boulders atop a cliff in North Eleuthera, Bahamas. We combine geologic field surveys, wave models, and boulder transport equations to test the hypothesis that such boulders must have been emplaced by storms of greater-than-historical intensity. By contrast, our results suggest that with the higher relative sea level (RSL) estimated for the Bahamas during MIS 5e, boulders of this size could have been transported by waves generated by storms of historical intensity. Thus, while the megaboulders of Eleuthera cannot be used as geologic proof for past "superstorms," they do show that with rising sea levels, cliffs and coastal barriers will be subject to significantly greater erosional energy, even without changes in storm intensity.
2D (SWAN) and 1D (XBeach) wave models for different grid domains in Eleuthera, North Bahamas. Modeled events are the Perfect Storm (1991), Hurricane Andrew (1992) and Hurricane Sandy (2012).
The models boundary conditions and forcing is described in the SI Annex of the paper.
The folder 2D WAve_models contains the results of SWAN runs for RSL=0m. Each file refers to one of the computational grids.
The folder 1D Wave_models contains the results of XBeach runs for RSL=0,3,6,9,12m. Each file represents three hours of simulations.