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Hurricanes Gilbert (8–19 September 1988) and Hugo (10–22 September 1989) are two of the largest and most destructive landfalling hurricanes in recent history. Differences in regional geography and type of coastal development, as well as storm size, track, and tidal stage at landfall had profound effects on the storm response of developed shorelines. In both the Yucatan Peninsula, Mexico (Gilbert) and South Carolina (Hugo), storm damage was increased by notching or removing dunes for development or beach access and by siting development at low elevations or ‘too close’ to the shoreline. High and wide dune fields, coastal forests, construction at high elevations, and building setbacks helped mitigate storm damage.

[1] We employ a numerical model to study the development of sorted bed forms under a variety of hydrodynamic and sedimentary conditions. Results indicate that increased variability in wave height decreases the growth rate of the features and can potentially give rise to complicated, a priori unpredictable, behavior. This happens because the system responds to a change in wave characteristics by attempting to self-organize into a patterned seabed of different geometry and spacing. The new wavelength might not have enough time to emerge before a new change in wave characteristics occurs, leading to less regular seabed configurations. The new seabed configuration is also highly dependent on the preexisting morphology, which further limits the possibility of predicting future behavior. For the same reasons, variability in the mean current magnitude and direction slows down the growth of features and causes patterns to develop that differ from classical sorted bed forms. Spatial variability in grain size distribution and different types of net sediment aggradation/degradation can also result in the development of sorted bed forms characterized by a less regular shape. Numerical simulations qualitatively agree with observed geometry (spacing and height) of sorted bed forms. Also in agreement with observations is that at shallower depths, sorted bed forms are more likely to be affected by changes in the forcing conditions, which might also explain why, in shallow waters, sorted bed forms are described as ephemeral features. Finally, simulations indicate that the different sorted bed form shapes and patterns observed in the field might not necessarily be related to diverse physical mechanisms. Instead, variations in sorted bed form characteristics may result from variations in local hydrodynamic and/or sedimentary conditions.

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The 8 km of shoreline from Punta Higuero to Punta Cadena in Rincon, Puerto Rico is experiencing long-term coastal erosion. This study documents historical shoreline changes at Rincon for the period 1936-2005. Twelve historical shoreline positions were compiled from existing data, new orthophotography, and GPS field surveys.

A change-potential index (CPI) was used to map the relative coastal change-potential of the shoreline to future sea-level changes within Kenai Fjords National Park (KEFJ) in south-central Alaska. The CPI ranks the following parameters in terms of their physical contribution to coastal change: geomorphology, regional coastal slope, rate of relative sea-level change, historical shoreline change rates, mean tidal range, and mean significant wave height. The rankings for each input variable were combined, and an index value was calculated for 1-minute grid cells covering the park. The CPI highlights those regions where the physical effects of sea-level and coastal changes might be the greatest. This multi-parametric approach combines the coastal system's potential for change with its natural ability to adapt to changing environmental conditions, yielding a quantitative, although relative, measure of the park's natural susceptibility to the effects of sealevel variation. The CPI provides an objective technique for evaluation and long-term planning by scientists and park managers. The CPI was developed from a Coastal Vulnerability Index (CVI) typically applied to coastlines undergoing long-term sea-level rise. The CPI is modified from the CVI and applied to the emergent coast of Kenai Fjords National Park to understand the limits of applying this type of assessment method in a variety of sea-level settings. Kenai Fjords National Park consists of sand and gravel beaches, rock cliffs, calving tidewater glaciers, mudflats, and alluvial fans. The areas within Kenai Fjords National Park that are likely to be most susceptible to coastal change as a result of sea-level change are tidewater glaciers and outer coast shorelines of unconsolidated sediment where shoreline erosion potential is high and wave energy is high.

4 Introduction 4 Data Ranking 5 The Gateway National Recreation Area 5 The Breezy Point District 6 Staten Island Unit 6 Sandy Hook Unit 6 Jamaica Bay Unit 6 Methodology 7 Geologic Variables 7 Physical Process Variables 7 Coastal Vulnerability Index 8 Results 8 Discussion 9 Conclusions 9 References 10 List of Figures 11 References 12 Coastal Vulnerability Assessment of Gateway National Recreation Area (GATE) to Sea-Level Rise By Elizabeth A. Pendleton, E. Robert Thieler, S. and Jeffress Williams

4 Introduction 4 Data Ranking 5 The Virgin Islands National Park 5 Methodology 6 Geologic Variables 6 Physical Process Variables 7 Coastal Vulnerability Index 7 Results 8 Discussion 8 Conclusions 8 References 9 List of Figures 10 List of Tables 12 Coastal Vulnerability Assessment of Virgin Islands National Park (VIIS) to Sea-Level Rise By Elizabeth A. Pendleton, E. Robert Thieler, S. and Jeffress Williams

4 Introduction 4 Data Ranking 5 The Golden Gate National Recreation Area 5 Methodology 6 Geologic Variables 6 Physical Process Variables 7 Coastal Vulnerability Index 7 Results 8 Discussion 8 Conclusions 9 References 9 List of Figures 10 Tables 12 Coastal Vulnerability Assessment of Golden Gate National Recreation Area to Sea-Level Rise By Elizabeth A. Pendleton, E. Robert Thieler, S. and Jeffress Williams

4 Introduction 4 Data Ranking 5 War in the Pacific National Historical Park 5 Methodology 6 Geologic Variables 6 Physical Process Variables 7 Coastal Vulnerability Index 7 Results 8 Discussion 8 Conclusions 8 References 9 List of Figures 10 List of Tables 11 Coastal Vulnerability Assessment of War in the Pacific National Historical Park to Sea-Level Rise By Elizabeth A. Pendleton, E. Robert Thieler, S. and Jeffress Williams

A coastal vulnerability index (CVI) was used to map relative vulnerability of the coast to future sea-level rise within Assateague Island National Seashore (ASIS) in Maryland and Virginia. The CVI ranks the following in terms of their physical contribution to sea-level rise-related coastal change: geomorphology, regional coastal slope, rate of relative sea-level rise, shoreline change rates, mean tidal range and mean wave height. Rankings for each variable were combined and an index value calculated for 1-minute grid cells covering the park. The CVI highlights those regions where the physical effects of sea-level rise might be the greatest. This approach combines the coastal system's susceptibility to change with its natural ability to adapt to changing environmental conditions, yielding a quantitative, although relative, measure of the park's natural vulnerability to the effects of sea-level rise. The CVI provides an objective technique for evaluation and long-term planning by scientists and park managers. Assateague Island consists of stable and washover dominated portions of barrier beach backed by wetland and marsh. The areas within Assateague that are likely to be most vulnerable to sea-level rise are those with the highest occurrence of overwash and the highest rates of shoreline change.