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

News: Summer Research Experience

2017/09/28 – DHS CRCoE
Students participate in second annual summer exchange program

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Summer activities also included a one-day exchange where students from Johnson C. Smith University (JCSU) in Charlotte, N.C., visited North Carolina State University (NCSU). Nine students enrolled in a summer research program led by Dr. Hang Chen visited the NCSU Department of Civil, Construction, and Environmental Engineering (CCEE), where CRC PI Dr. Casey Dietrich exposed the students to the concepts of computing-intensive and coastal resilience research.

The visiting students learned about the CCCE department, along with summer and graduate program opportunities. Dr. Dietrich arranged presentations and discussions with faculty members in their computing and system group. Ten faculty members presented their interdisciplinary research projects addressing problems throughout civil and environmental engineering using computational tools. The JCSU students also interacted with Dr. Dietrich’s graduate students and learned more about their individual research projects.

News: Storm Surge Impacts during Hurricane Irma

2017/09/14 – The Daily Tar Heel
Hurricane Irma lets North Carolina off easy

Casey Dietrich, an assistant professor at N.C. State University, said Hurricane Irma’s effects were relatively minor in coastal North Carolina because its track was so far away.

“Along the southeast coast between Wilmington and Myrtle Beach, the wind speeds barely reached the cutoff for tropical-storm strength, 39 miles per hour, and only for a few hours,” he said.

Dietrich also works as a part of the Coastal Resilience Center, a group of universities, private companies and government agencies that are led by UNC. The CRC conducts research on the threats to coastal communities due to natural hazards and climate change.

CCHT Hosts Visitors from Johnson C. Smith University

Nine students in the Summer Research Program at Johnson C. Smith University visited the NCSU Department of Civil, Construction, and Environmental Engineering and were hosted by Dr. Casey Dietrich. This program is supported by the DHS Coastal Resilience Center of Excellence.

The director of graduate programs gave an overview of the NCSU CCCE department and summer and graduate programs opportunities. Dr. Dietrich arranged presentations and discussions with faculty members in the Computing & Systems group.

Dr. Dietrich poses with JCSU students outside of Mann Hall.

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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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Seminar: NWS Raleigh