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This paper describes the development of a procedure to quantify errors in hurricane storm surge simulations using a decoupled wind-surge model. The state-of-the-art storm surge simulation program, advanced circulation (ADCIRC), and the Georgiou's wind-field model were used to simulate the storm surge heights associated with 169 historical hurricanes from 1922 to 2011 along the coasts of North Carolina, South Carolina, and Georgia. The storm surge modeling errors were quantified by comparing the measured with the simulated annual maximum surge heights at nine water-level observation stations maintained by the Center for Operational Oceanographic Products and Services (CO-OPS). The simulated surge heights consisted of both systematic and random errors. A power equation was used to adjust the systematic errors in the simulated storm surge heights. The random errors, which are defined as the ratio of the measured to the systematic error-adjusted simulated annual maximum surge heights, were found to follow a lognormal distribution. To confirm the validity of the error quantification methodology, the simulated annual, 5-year, and 10-year maximum surge heights were adjusted using the modeling errors quantified for each of the nine CO-OPS water stations and compared with the actual storm surge observations. Good agreements were observed between the actual measurements and the error-adjusted surge elevations. The proposed methodology for quantifying modeling errors can be applied to adjust for storm surge predictions of longer return periods and can be used to develop design surge hazard maps. [ABSTRACT FROM AUTHOR]

This paper presents the development of a shear-wave velocity (V S) model of reference site conditions in South Carolina for site response analysis and seismic hazard mapping. Model development involves creating contour maps of two geologic surfaces in the Coastal Plain with high contrasts in V S and combining the results with median V S profiles that extend to hard rock (V S ≥ 3000 m/s). Uncertainties associated with the contour maps of depth are captured in maps of the standard prediction error. Values of time-averaged V S in the top 30 m (V S,30) ranging from 1183 to 1538 m/s and 354 to 385 m/s characterize the reference site conditions in the Blue Ridge and Piedmont regions and the Coastal Plain region, respectively. The model is divided into 14 zones to facilitate site response analysis and to avoid over-smoothing resonances due to the impedance contrasts. This study is part of a larger effort to develop statewide probabilistic seismic hazard maps for the South Carolina Department of Transportation. • A geology-based, shear-wave velocity (V S) model of reference site conditions in South Carolina is developed. • Two depth contour maps are created: 1) Top of the Jurassic and older basement; and 2) Bottom of the Santee Limestone. • V S30 for reference outcrop site conditions are between 354 m/s and 385 m/s in Coastal Plain of South Carolina. • In the South Carolina Blue Ridge and Piedmont, V S30 for reference outcrop site conditions range from 1183 to 1518 m/s. • South Carolina is divided into 14 zones for the purposes of site response analysis. [ABSTRACT FROM AUTHOR]