Sensitivity study of St Andrew Bay rapid response system for Naval applications

1. Sensitivity study of St Andrew Bayrapid response system for Naval applications LCDR Patrice Pauly, French Navy Thesis Advisor: Pr. Peter C. Chu, NPS Second Reader: Steven D. Haeger, NAVOCEANO

2. Outlines • Geographic location • Hydrodynamic model used in this study • Forcing mechanisms and Sensibility study • Hydrochemical model and naval applications • Conclusion and recommendations

3. Geographic location - overview • Northeastern Gulf of Mexico • Part of the Intracoastal highway • Fed by Deer Point Lake dam Deer Point Lake dam

4. Geographic location - bathymetry Panama City Beach Panama City West boundary East boundary West Pass East Pass Point A Point B

5. Beach City Geographic location - bathymetry Panama City Beach Panama City West boundary East boundary West Pass East Pass Point A Point B

6. West boundary East boundary Geographic location - bathymetry Panama City Beach Panama City West boundary East boundary West Pass East Pass Point A Point B

7. West Pass East Pass Geographic location - bathymetry Panama City Beach Panama City West boundary East boundary West Pass East Pass Point A Point B

8. A B Geographic location - bathymetry Panama City Beach Panama City West boundary East boundary West Pass East Pass Point A Point B

9. Hydrodynamic model – WQMAP • General equations: • Momentum equations • Continuity equation • Transport equation • Stability condition (1) (2) (3) (4)

10. Hydrodynamic model – grid generation

11. Hydrodynamic model – bathymetry smoothing effects

12. Hydrodynamic model – WQMAP • Approximations: • Shallow waters • Boussinesq • Incompressibility • Boundary conditions: • No flow through surface or bottom • No flow perpendicular to the shoreline • No transport of salt at closed boundaries • Study configuration: • 3D-version with 10 layers • Rectangular 550m-wide cells grid • 2m-minimum cell depth applied after bathymetry smoothing • Time step of 0.1min

13. 55 242 151 All values in m3/s 214 476 257 293 642 Sensibility study - methodology • The control run featured with: • Tidal time series at all open boundaries • Tidal residual time series at Gulf entrances • Wind time series • Fresh water supply from drainage sub-basins • 21˚C constant water temperature • Constant salinity values of 22, 20 and 35 psu at West Bay, East Bay and West Pass open boundary respectively

14. Data analysis – fresh water supply

15. Salinity impact and steady state Model is featured with salinity only Surface layer Bottom layer

16. Hydrodynamic model – steady state

17. +55 -1 -1 +4 +21 -7 -8 -28 Flux differences (m3/s) between this case and the control run Fresh water impact This case was featured with a doubled river runoff. West Bay (top) – West Pass (middle) – Point A (bottom)

18. Data analysis – sea surface temperature • Data set collected at • Panama City Beach • Panama City Station • Averaged between2000-2004 • Varies from 15˚C in winter up to 30˚C in summer • Well-mixed through the water column

19. Data analysis – wind Wind values (m/s) averaged over the past 60 years. 2004 average: 0.12m/s northwesterlies May through September average: 4m/s from 155. Can easily reach 20m/s and more during hurricane events

20. Wind impacts 20m/s 25m/s 09/16 at 05:00 AM 09/16 at 01:20 PM

21. 0 -23 +21 West Pass West Bay East Bay -24 -24 -6 0 -49 Flux differences (m3/s) between this case and the control run Wind impact Surface layer • We featured two cases: • wind removed • a normalized error (μ=0, σ=1m/s) applied on both u and v-components. Bottom layer

22. 0 -13 -3 East Bay West Bay West Pass 0 -4 -5 -9 -2 Flux differences (m3/s) between this case and the control run Wind impact Surface layer • We featured two cases: • wind removed • a normalized error (μ=0, σ=1m/s) applied on both u and v-wind components. Bottom layer

23. Data analysis – tides from NOAA Panama City Beach station: amplitude in cm phase in deg. K1: 15.89 (0.3) 296.2 (1) O1: 15.84 (0.3) 284.8 (1) Q1: 3.4 (0.3) 270.7 (5.5) M2: 3.4 (0.1) 287.4 (1.5) S2: 2 (0.1) 303.1 (2.5) • NOAA website provides: • Tidal gauge time series • Tidal constituents

24. Data analysis – tides from NOAA • NOAA website provides: • Tidal gauges time series • Tidal constituents

25. Data analysis – tides from Wxtide32 • Embedded tidal software Wxtide32 • Uses open data only • Almost Worlwide • Provided time series for all open boundaries

26. Tidal impact on speed West Pass West Bay

27. Tidal impact on salinity East Bay West Bay

28. Tidal impact on salinity at point A • Two remarks: • salt propagates trough two different processes • ebb and flood tides are not equally long

29. 0 -1 0 -1 -3 -2 -4 -2 Flux differences (m3/s) between this case and the control run Tidal impact This case was featured with a modified K1-coefficient amplitude (14.5cm in stead of 15.5) at West Pass.

30. Data analysis – tidal residuals • Due to: • Wave setup • Storm surge • Averages 7.73 cm • with a 13.6 cm standard deviation

31. 0 -180 -72 East Bay West Pass West Bay -104 -289 -177 -123 -392 Flux differences (m3/s) between this case and the control run Residual impact Surface layer This case was featured without residual time series Bottom layer

32. WQMAP coupled rapid response models

33. CHEMMAP overview • Chemical database: • international references • physical properties (solubility, volatility, floatability) • Chemical fate model: • Lagrangian approach • spreading, entrainment, evaporation, dispersion, dissolution, sedimentation and degradation • vertical velocity relies on Stoke’s Law • mass transported with wind field and WQMAP issued currents. • Use of Ethylene Glycol • Sinker • Highly soluble • Non volatile • 10 tons released within 10 hours • Release at bottom • Wind impact: • 3% of wind speed • 20˚ drift to the right

34. Release the 1st of June – 12:00am Spill dispersion after 3 weeks

35. Release the 1st of June – 12:00am

36. Wind effects on spill propagation No wind simulation Inversed wind simulation

37. Release time influence – stochastic model 50 cases from 1st of June to 31st of August Run number for worst case scenario

38. Release location influence

39. Time response delay Minimum time to exceed a threshold

40. Conclusion • The hydrodynamic model: • shows the baroclinicity of St Andrew Bay system, • proved the fresh water input accuracy not to be essential, • proved the tidal residual to run the fluxes in the whole basin, • confirmed the wind influence on stratification, • allowed the salt diffusion process to be identified. • The hydrochemical model: • enhanced the aforementioned conclusions, • emphasizes the importance of wind in driving pollution.

41. Future improvements and recommendations • The hydrodynamic model: • Is underground seepage realistically modeled by river cells ? • Are the open boundaries correctly located ? • the smoothing process effects should be further investigated, • strong weather events impact should be evaluated. • The hydrochemical model: • Should include vertical salinity distribution. Please offer OC 4212 – Tides.

42. Questions