Multi-Model Validation of Currents in the Chesapeake Bay Region in June 2010

Abstract

In this paper, we discuss the validation of water level and current predictions from three coastal hydrodynamic models and document the resource and operational requirements for each modeling system. The ADvanced CIRCulation Model (ADCIRC), the Navy Coastal Ocean Model (NCOM), and Delft3D have been configured and validated for the Chesapeake Bay region during a Navy exercise. Water level predictions are compared with a NOAA/NOS water level gauge at the Chesapeake Bay Bridge Tunnel location while current predictions are validated with Acoustic Doppler Profiler (ADP) measurement records at three locations in the lower Chesapeake Bay. Statistical metrics such as correlation coefficient and root mean square error (RMSE) are computed. Both the vertically-integrated currents and currents at varying water depths are compared as well. The model-data comparisons for surface elevation indicate all three models agreed well with water level gauge data. The two-dimensional version of ADCIRC, ADCIRC2D, and NCOM yield better statistics, in terms of correlation and RMSE, than Delft3D. For vertically-integrated currents, ADCIRC2D has the smallest RMSE at Thimble Shoal and Naval Station locations while NCOM has the smallest RMSE at Cape Henry. For the horizontal currents over the water column, the fully three-dimensional, baroclinic ADCIRC model, ADCIRC3D, and NCOM both showed better agreement with the ADP measurements.

Keywords:

• Chesapeake Bay
• model validation
• coastal models
• currents
• water levels
• NCOM
• Delft3D
• ADCIRC

Acknowledgements

The authors would like to thank Paula Costello at NAVO and Kacey Edwards at NRL for their assistance in preparing and post-processing the Delft3D simulation results. The authors thank the reviewers for their helpful suggestions and comments. This paper is contribution NRL/JA/7320/11/856 and has been approved for public release.

This article not subject to U.S. copyright law.