@article{thomas_dietrich_dawson_luettich_2022, title={Effects of Model Resolution and Coverage on Storm-Driven Coastal Flooding Predictions}, volume={148}, ISSN={["1943-5460"]}, url={https://doi.org/10.1061/(ASCE)WW.1943-5460.0000687}, DOI={10.1061/(ASCE)WW.1943-5460.0000687}, abstractNote={Predictions of storm surge and flooding require models with higher resolution of coastal regions, to describe fine-scale bathymetric and topographic variations, natural and artificial channels, flow features, and barriers. However, models for real-time forecasting often use a lower resolution to improve efficiency. There is a need to understand how resolution of inland regions can translate to predictive accuracy, but previous studies have not considered differences between models that both represent conveyance into floodplains and are intended to be used in real time. In this study, the effects of model resolution and coverage are explored using comparisons between forecast-ready and production-grade models that both represent floodplains along the US southeast coast, but with typical resolutions in coastal regions of 400 and 50 m, respectively. For two storms that impacted the US southeast coast, it is shown that, although the overall error statistics are similar between simulations on the two meshes, the production-grade model allowed a greater conveyance into inland regions, which improved the tide and surge signals in small channels and increased the inundation volumes between 40% and 60%. Its extended coverage also removed water level errors of 20–40 cm associated with boundary effects in smaller regional models.}, number={1}, journal={JOURNAL OF WATERWAY PORT COASTAL AND OCEAN ENGINEERING}, publisher={American Society of Civil Engineers (ASCE)}, author={Thomas, Ajimon and Dietrich, J. C. and Dawson, C. N. and Luettich, R. A.}, year={2022}, month={Jan} }
 @article{thomas_dietrich_loveland_samii_dawson_2021, title={Improving coastal flooding predictions by switching meshes during a simulation}, volume={164}, ISSN={["1463-5011"]}, url={https://doi.org/10.1016/j.ocemod.2021.101820}, DOI={10.1016/j.ocemod.2021.101820}, abstractNote={Storm surge and coastal flooding predictions can require high resolution of critical flow pathways and barriers, typically with simulations using grids/meshes with millions of cells/elements to represent a coastal region. However, the cost of this resolution can slow forecasts during a storm. To add resolution when and where it is needed, previous studies have used adaptive mesh methods, which update resolution at single or multiple cells but which require hierarchies of and thresholds for refinement, and nesting methods, which update resolution at subdomains but which require additional simulations. This research proposes a middle way, in which predictions from a coarse mesh are mapped, mid-simulation, onto a fine mesh with increased resolution near the storm's projected landfall location. The coarse and fine meshes are pre-developed, thus removing any refinement decisions during the simulation, the solution mapping uses a widely used framework, thus enabling an efficient interpolation, and the same simulation is continued, thus eliminating a separate full-domain simulation. For four historical storms, results show efficiency gains of up to 53 percent, with minimal accuracy losses relative to a static simulation.}, journal={OCEAN MODELLING}, author={Thomas, Ajimon and Dietrich, J. C. and Loveland, M. and Samii, A. and Dawson, C. N.}, year={2021}, month={Aug} }
 @article{thomas_dietrich_asher_bell_blanton_copeland_cox_dawson_fleming_luettich_et al._2019, title={Influence of storm timing and forward speed on tides and storm surge during Hurricane Matthew}, volume={137}, ISSN={1463-5003}, url={http://dx.doi.org/10.1016/j.ocemod.2019.03.004}, DOI={10.1016/j.ocemod.2019.03.004}, abstractNote={The amount and extent of coastal flooding caused by hurricanes can be sensitive to the timing or speed of the storm. For storms moving parallel to the coast, the hazards can be stretched over a larger area. Hurricane Matthew was a powerful storm that impacted the southeastern U.S. during October 2016, moving mostly parallel to the coastline from Florida through North Carolina. In this study, three sources for atmospheric forcing are considered for a simulation of Matthew's water levels, which are validated against extensive observations, and then the storm's effects are explored on this long coastline. It is hypothesized that the spatial variability of Matthew's effects on total water levels is partly due to the surge interacting nonlinearly with tides. By changing the time of occurrence of the storm, differences in storm surge are observed in different regions due to the storm coinciding with other periods in the tidal cycles. These differences are found to be as large as 1 m and comparable to the tidal amplitude. A change in forward speed of the storm also should alter its associated flooding due to differences in the duration over which the storm impacts the coastal waters. With respect to the forward speed, the present study contributes to established results by considering the scenario of a shore-parallel hurricane. A faster storm caused an increase in peak water levels along the coast but a decrease in the overall volume of inundation. On the other hand, a slower storm pushed more water into the estuaries and bays and flooded a larger section of the coast. Implications for short-term forecasting and long-term design studies for storms moving parallel to long coastlines are discussed herein.}, journal={Ocean Modelling}, publisher={Elsevier BV}, author={Thomas, Ajimon and Dietrich, JC and Asher, TG and Bell, M and Blanton, BO and Copeland, JH and Cox, AT and Dawson, CN and Fleming, JG and Luettich, RA and et al.}, year={2019}, month={May}, pages={1–19} }