Sensitivity of Storm Surge Predictions to Atmospheric Forcing during Hurricane Isaac

Storm surge and overland flooding can be predicted with computational models at high levels of resolution. To improve efficiency in forecasting applications, surge models often use atmospheric forcing from parametric vortex models, which represent the surface pressures and wind fields with a few storm parameters. The future of storm surge prediction could involve real-time coupling of surge and full-physics atmospheric models; thus, their accuracies must be understood in a real hurricane scenario. The authors compare predictions from a parametric vortex model (using forecast tracks from the National Hurricane Center) and a full-physics coupled atmosphere-wave-ocean model during Hurricane Isaac (2012). The predictions are then applied within a tightly coupled, wave and surge modeling system describing the northern Gulf of Mexico and the floodplains of southwest Louisiana. It is shown that, in a hindcast scenario, a parametric vortex model can outperform a data-assimilated wind product, and given reasonable forecast advisories, a parametric vortex model gives reasonable surge forecasts. However, forecasts using a full-physics coupled model outperformed the forecast advisories and improved surge forecasts. Both approaches are valuable for forecasting the coastal impacts associated with tropical cyclones

JC Dietrich, A Muhammad, M Curcic, A Fathi, CN Dawson, SS Chen, RA Luettich (2018). “Sensitivity of Storm Surge Predictions to Atmospheric Forcing during Hurricane Isaac.Journal of Waterway, Port, Coastal, and Ocean Engineering, 144(1), DOI: 10.1061/(ASCE)WW.1943-5460.0000419

Seminar: UNC Department of Geological Sciences

Conference: ADCIRC 2017

R Cyriac, JC Dietrich, A Fathi, CN Dawson, KM Dresback, CA Blain, M Bilskie, SC Hagen, H Graber. “Circulation Dynamics and Transport Characteristics of Density-driven Flows in the Choctawhatchee Bay and River System.” ADCIRC Users Group Meeting,¬†Norwood, Massachusetts, 04 May 2017.

A Thomas, JC Dietrich, RA Luettich, JG Fleming, BO Blanton, TG Asher, SC Hagen, MV Bilskie, P Bacopoulos. “Hindcasts of Winds and Surge during Hurricane Matthew (2016): Balancing Large-Domain Coverage and Localized Accuracy.” ADCIRC Users Group Meeting,¬†Norwood, Massachusetts, 04 May 2017.

A Gharagozlou, JC Dietrich, A Karanci, MF Overton, RA Luettich Jr. “XBeach Modeling of Erosion During Hurricane Isabel: Resolution Requirements For Coupling With ADCIRC.” ADCIRC Users Group Meeting, Norwood, Massachusetts, 05 May 2017.

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Conference: NCBIWA 2016

How to Run Kalpana

Kalpana converts ADCIRC output files in netCDF format to Google Earth (kmz) or GIS shapefiles for use with conventional GIS software. The latest version of the code is maintained at our GitHub repository: https://github.com/ccht-ncsu/Kalpana.

Command line arguments control the way it produces output, including the number of contour levels, their values, and the color scale. When these specifications are absent from the command line, it uses reasonable default settings so in many cases only a few of the available command line options will be used for any particular plot.

Visualization of Maximum Water Levels along the North Carolina coast during Hurricane Arthur (2014) using polygon shapefiles created by Kalpana with ArcGIS satellite imagery.

Visualization of Maximum Water Levels along the North Carolina coast during Hurricane Arthur (2014) using polygon shapefiles created by Kalpana with ArcGIS satellite imagery.

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