1. US IOOS Modeling Testbed Leadership Teleconference May 3, 2011 FVCOM Development Team Robert C. Beardsley and Changsheng Chen Email: rbeardsley@whoi.edu; c1chen@umassd.edurbeardsley@whoi.edu Phone: 508-280-2536 (Beardsley); 508-910- 6388 (Chen)

2. Outcomes and Scientific Insights Gained Developed a wave-current interaction inundation FVCOM system for extratropical storms. This system has been validated for selected 2005, 2007 and 2010 Nor’easter storms, and is being used for hurricane inundation simulation for the Gulf of Mexico shelf. In Scituate experiments, the model shows that wave-current interaction plays a key important role in producing the inundation. The interaction significantly increases water transport into the harbor and intensifies an anti-cyclonic eddy that forms in the entrance, which in turn pushes water against the coast and thus causes flooding. In the case without waves, the currents are generally oriented parallel to the local isobaths. In the case with waves, the currents turn coastward, which can produce a significant onshore water flux. The Nor’easter storm-induced inundation occurs in a short time period and also the maximum flooding is at or near high tide.

3. Outcomes and Scientific Insights Gained A subgrid 3-D FVCOM Scituate inundation forecast system is being implemented into the Northeast Coastal Ocean Forecast System (NECOFS) and placed into routine forecast operation. A collaboration with the NOAA National Weather Service Weather Forecast Office (WRO) in Taunton has been established. Several meetings were been held and a plan was made in April on methods to transfer a variety of the forecast products to the Taunton WFO.

4. Summarize Testbed Products Completed by June A subgrid, 3-D, fully coupled wave-current inundation FVCOM system has been developed, and configured for Scituate, MA. This system is also being used for the testbed hurricane- induced storm surge experiments in the Gulf of Merixo shelf; The Scituate system was first validated for tidal simulation with comparison to the sea level time series data collected in the harbor. Completed 2005 and 2007 Nor’easter experiments. For the 2007 experiments, we have run the model for the three cases: 1) with waves only, 2) with currents only, and 3) with wave- current interaction. We also assessed the contributions of 1) the air pressure gradient and 2) wind gustiness by re-running the model with inclusion of these forcings. All model products were saved as NetCDF format and uploaded into the testbed website. For the 2005 experiment, we have completed all experiments for the case without considering the effect of wind gusts. All model results were also uploaded onto the testbed website. All the experiments were made using the 3-D subgrid FVCOM Scituate inundation system. The system was also applied in forecast mode for the 2010 Dec. 27 Nor’easter storm, and showed success in predicting the coastal inundation that occurred within Scituate Harbor. which shows a success in the prediction of the coastal inundation in Scituate.

5. Anticipated Progress During NCE (Jun-Dec) Work will focus on model validation via field measurements and model- model comparisons for the 2005 and 2007 extratropical storm events. The team will lead the model-model comparison. We will refine the Scituate grid and investigate how the inundation results depend on model resolution. Testbed funding will be used mainly for salary support for Qichun Xu (Research Associate), with modest funding for project travel, etc.

6. Challenges to Progress and Lessons Learned Including wave-current interaction significantly increases the computational power needed for a inundation simulation. When using the same number of nodes, the time required to run the coupled current-wave system is usually eight to ten times more than the case without waves. The wind gust effect. We found that in the 2010 Nor’easter event, the using the gust wind instead of the mean wind to compute the surface wind stress and energy input increases the wind energy input by 24%. Since inundation usually occurs at the maximum wind and high tide, correctly incorporating the gust winds is a critical issue in making accurate inundation hindcasts/forecasts.

7. How Can TAEG Help You? How can SURA Mgmt Help You? We need to have a more easy and advanced tool for model assessment. For very large model data sets, using Matlab to compute statistics (e.g. means, stds, vertical averages is very slow. To improve efficiency, analysis tools could be rewritten in Fortran and made able to work on parallel machines.

8. Presentations at Scientific Meetings 1)R. Beardsley, C. Chen, Q. Xu, J. Qi, and H. Lin, 2011. Extratropical Storm-Induced Coastal Inundation: Scituate, MA. Inundation TestBed Workshop, North Carolina University, March 7-8, 2011. 2)R. Beardsley and C. Chen, 2011. Progress of Development of the Scituate Inundation Forecast System. Meeting with NWS, Taunton, March 18, 2011. 3)R. Beardsley and C. Chen, 2011. Using NECOFS to predict inundation in Scituate, MA: a preliminary assessment. Poster, Gordon Conference on Coastal Ocean Modeling, South Hampton, June, 2011.