[1] This paper investigates the effects of waves on storm surge, currents, and inundation in the Outer Banks and Chesapeake Bay during Hurricane Isabel in 2003 through detailed comparison between observed wind, wave, surge, and inundation data and results from an integrated storm surge modeling system, CH3D-SSMS. CH3D-SSMS, which includes coupled coastal and basin-scale storm surge and wave models, successfully simulated measured winds, waves, storm surge, currents, and inundation during Isabel. Comprehensive modeling and data analysis revealed noticeable effects of waves on storm surge, currents, and inundation. Among the processes that represent wave effects, radiation stress (outside the estuaries) and wave-induced stress (outside and inside the estuaries) are more important than wave-induced bottom stress in affecting the water level. Maximum surge was 3 m, while maximum wave height was 20 m offshore and 2.5 m inside the Chesapeake Bay, where the maximum wave-induced water level reached 1 m. Significant waves reached 3.5 m and 16 s at Duck Pier, North Carolina, and 1.6 m and 5 s at Gloucester, Virginia. At Duck, wave effects accounted for $36 cm or 20% of the peak surge elevation of 1.71 m. Inside the Chesapeake Bay, wave effects account for 5-10% of observed peak surge level. A two-layer flow is found at Kitty Hawk, North Carolina, during the peak of storm surge owing to the combined effects of wind and wave breaking.

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With recent advances in virtual computing and the revelation that compute-intensive tasks run well on system virtual machines (VMs), the ability to develop, deploy, and manage distributed systems has been ameliorated. This paper explores the design space of VM-based sandboxes where the following techniques that facilitate the deployment of secure nodes in Widearea Overlays of virtual Workstations (WOWs) are employed: DHCP-based virtual IP address allocation, self-configuring virtual networks supporting peer-to-peer NAT traversal, stacked file systems, and IPsec-based host authentication and end-to-end encryption of communication channels.Experiments with implementations of single-image VM sandboxes, which incorporate the above features and are easily deployable on hosted I/O VMMs, show execution time overheads of 10.6% or less for a batchoriented CPU-intensive benchmark.

To create more useful storm surge and inundation forecast products, probabilistic elements are being incorporated. To achieve the highest levels of confidence in these products, it is essential that as many simulations as possible are performed during the limited amount of time available. This paper develops a framework by which probabilistic storm surge and inundation forecasts within the Curvilinear Hydrodynamics in 3D (CH3D) Storm Surge Modeling System and the Southeastern Universities Research Association Coastal Ocean Observing and Prediction Program's forecasting systems are initiated with specific focus on the application of these methods in a limited-resource environment. Ensemble sets are created by dividing probability density functions (PDFs) of the National Hurricane Center model forecast error into bins, which are then grouped into priority levels (PLs) such that each subsequent level relies on results computed earlier and has an increasing confidence associated with it. The PDFs are then used to develop an ensemble of analytic wind and pressure fields for use by storm surge and inundation models. Using this approach applied with official National Hurricane Center (OFCL) forecast errors, an analysis of Hurricane Charley is performed. After first validating the simulation of storm surge, a series of ensemble simulations are performed representing the forecast errors for the 72-, 48-, 24-, and 12-h forecasts. Analysis of the aggregated products shows that PL4 (27 members) is sufficient to resolve 90% of the inundation within the domain and appears to represent the best balance between accuracy and timeliness of computed products for this case study. A 5-day forecast using the PL4 set is shown to complete in 83 min, while the intermediate PL2 and PL3 products, representing slightly less confidence, complete in 14 and 28 min, respectively.