Giant boulders and Last Interglacial storm intensity in the North Atlantic

@article{Rovere2017,
  Title = {Giant boulders and Last Interglacial storm intensity in the North Atlantic},
  Author = {Rovere, Alessio and Casella, Elisa and Harris, Daniel and Lorscheid, Thomas and Nandasena, Napayalage A. K. and Dyer, Blake and Sandstrom, Michael R. and Stocchi, Paolo and D’Andrea, William J. and Raymo, Maureen E.},
  Editor = {},
  Journal = {Proceedings of the National Academy of Sciences},
  Year = {2017},
  Pages = {12144-12149},
  Volume = {114},
  Doi = {10.1073/pnas.1712433114},
  Abstract = {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.},
}

TY  - JOUR
AU  - Rovere, Alessio
AU  - Casella, Elisa
AU  - Harris, Daniel
AU  - Lorscheid, Thomas
AU  - Nandasena, Napayalage A. K.
AU  - Dyer, Blake
AU  - Sandstrom, Michael R.
AU  - Stocchi, Paolo
AU  - D’Andrea, William J.
AU  - Raymo, Maureen E.
TI  - Giant boulders and Last Interglacial storm intensity in the North Atlantic
T2  - Proceedings of the National Academy of Sciences
PY  - 2017
SP  - 12144-12149
VL  - 114
DO  - 10.1073/pnas.1712433114
AB  - 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.
ER  -