Coupled Hydrodynamic and Water Quality Modeling of Florida Bay

Transcription

1 Coupled Hydrodynamic and Water Quality Modeling of Florida Bay John Hamrick Tetra Tech Jeff Ji AEE Florida Bay Science Conference December 10, 2008

2 Acknowledgement This work was funded by the South Florida Water Management District and benefited from the collaboration with numerous members of the Florida Bay scientific community

3 Outline Background Review of the Hydrodynamic Model Water Quality Modeling Approach Water Quality Data Set and Model Configuration Significant WQ Modeling Issues Water Quality Model Results Summary Future Directions

4 Background Proof of Concept Study Using EFDC Model: 2002 Focused on Freshwater Inflow Presented at Tampa FBS 2003? Grid Resolution Analysis: 2003 Technical Review Jan 2004 Hydrodynamic Model Calibration: 2004 Technical Review October 2005 Presented at 2005 FBS Water Quality Model Development: 2006 Workshop Jan 2007

5 A Model Includes The Code Representing a Space-Time Approximation of Physics and Biogeochemical Processes The Input Domain Representation including Bathymetry and Topography Boundary Conditions and Forcing Functions Process Parameters The Modeler Ability to Manipulate the Input and Use the Code to Achieve an Acceptable Approximation of Reality and Identify What is Missing and/or Uncertain

6 Hydrodynamic and Salinity Model EFDC Based Multiple Levels of Grid Resolution Historical Simulation Period Iterative Two-Way Coupling to TIME Model Demonstrated One-Way Coupling to HYCOM Model Calibrated to Water Surface Elevation, Currents, Temperature and Salinity Used to Evaluate Salinity Response to CERP Inflow Distribution Alternatives Used to Provide Physical Transport for WQ Model

7 Medium Resolution Grid with Wetlands

8 Medium Resolution Grid Nominal Coastline Version

9 Hydrodynamic Model: Water Surface Elevation Calibration Model and Predicted Harmonic Amplitudes Agree Well At Stations Which Are Not Strongly Influenced by Local Effects (Banks, etc) The Model Reproduces Observed Low Frequency Sea Level Variability In Central and Eastern Florida Bay Low Frequency Sea Level Forcing on Boundary Propagates with Little Attenuation to Eastern Bay Eastern Bay Response Indicates Local Wind Forcing Also Contributes to Variability Configuration with NE Wetlands Captures Some Observed Events Better Than Nominal Coastline Configuration

10 Zoom In of Observed and Predicted Low- Frequency Sea Level at Trout Cove

11 Hydrodynamic Model: Current Meter Calibration Model Reproduces Tidal Frequency Current Magnitudes, Phases and Angles Reasonably Well Model Reproduces NW-SE Low Frequency Current on SW Shelf Well Low Frequency Current Prediction Along 81d05m Needs Improvement and Could Benefit from Additional Bathymetric Data Over Eastern Banks Additional Low Frequency Current Meter Comparisons Were Made

12 North LF Current NOAA A

13 Hydrodynamic Model: Temperature Calibration Model Temperature Prediction Is Very Good at 12 of 14 Stations with Normalized RMS Error Less Than 5 % for Nominal and Wetland Configurations The 2 Stations with Over Prediction Have Normalized Errors of Less Than 13 % Over Prediction at These Station Is Due to Shallow Depth A Bed Thermal Layer Will Be Used to Improve These and Over Shallow Water Cells Evaporation Is Dynamically Predicted

14 Hydrodynamic Model: Salinity Calibration Two-Way Iterative Coupling with TIME Model Is Critical Nominal Coastline Currently Performs Better Than Wetlands Configuration Wetlands Configuration Does Not Include Surface- Ground Water Volume and Salinity Exchange Representation of Button Wood Embankment Can Be Refined Model Predicts Hyper-Salinity Hyper-Salinity Predicted Very Well at Garfield, Terrapin and Whipray Over Prediction at Johnson, Little Rabbit and Murray Refinement Could Address Basin Residence Time and Evaporation Prediction

15 Whipray Basin Salinity

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17 Calibration and Performance Measures What Measures Good Performance? Comparison of Observed and Predicted Means and Standard Deviations Mean Absolute Error and Normalized MAE Most Widely Used Error for WQ Models Root Mean Square Errors Index of Agreement, A Normalized RMS Error with 0<COI<1 Compare with Results for Other Water Bodies

18 Index of Agreement Skill Parameter IA = 1 M m= 1 n= 1 M N ( O P ) mn, mn, m= 1 n= 1 N ( ) P O + O O mn, mn, 0 IA 1 2 2

19 Florida Bay Salinity Calibration Compared with Chesapeake Bay Index of Agreement, A Normalized RMS Error with 0<COI<1 Li, Zhong, & Boicourt Chesapeake Bay Reported Range of 0.46 to 0.96 with a Mean of 0.76 (Monitoring Observations) Florida Bay Range 0.57 to 0.88 with a Mean of 0.79 for Continuous ENP Observations Florida Bay Range 0.58 to 0.85 with a Mean of 0.71 for FIU Monitoring (Shelf and Straits Excluded)

20 Water Quality Modeling Approach Builds on the Previous WQ Modeling Study COE CE-QUAL-ICM WQ Model 30 Day RMA10 Hydrodynamics Recycled 2 Year Model Simulations Current EFDC WQ Model Hydrodynamic and WQ Run Simultaneously for 8 Year Simulations Same Basic WQ Formulation Formulation Reviewed by Dr. Carl Cerco

21 EFDC Water Quality Overview Directly coupled to hydrodynamics. No external linking is required Based on CE-QUAL-IC (Chesapeake Bay WQ Model) kinetics previously used for Florida Bay 22 water column state variables including multiple classes of algae and organic carbon, nitrogen and phosphorous Sediment diagenesis/flux sub-model with 27 state variable Generic rooted aquatic plant sub-model with most of the features of the FB Sea Grass Model

22 EFDC Water Quality Schematic RPOC RPON RPOP SU LPOC LPON LPOP DOC DON DOP NH4 PO4t SA PO4d SAd NO23 PO4p SAp DO photosynthesis light TSS* or reaeration respiration TAM COD Bc Bg Bd FCB * TSS from hydrodynamic model

23 Observational Data for Water Quality Model Configuration and Calibration ENP Interior - Load estimation Florida Bay - Load estimation and calibration Ten Thousand Islands Load estimation Southwest Florida Shelf Open boundary conditions and calibration Florida Keys Open boundary conditions and calibration Various Process Orient Studies

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25 Southwest Shelf and Keys Stations

26 Configuration and Calibration Approach Boundary Conditions Well defined for calibration period Estimation and Adjustment of Loads Correlation of inflow with concentrations Splitting of organic matter loads into labile and refractory reaction classes Sensitivity with respect to loads demonstrated Adjustment of Reaction Rates and Parameters Constrained to be within scientifically acceptable range Enhancement of Water Quality Processes Representations

27 Example of Loading Functions 7-9 STA# FB 10 R^2 = Y=A+B*X+C*X^2+D*X^3 A = -4.66E+002 B = 1.11E C = -1.08E+001 D = 7.76E R^2 = Y = A + B*X + C*X^2 + D*X^3 A = -2.73E+001 B = 6.37E+001 C = -8.53E-001 D = 6.54E-003 STA# FB R^2 = Y=A+B*X+C*X^2+D*X^3 A = -2.39E+001 B = 1.11E+001 C = -3.19E-001 D = 4.83E-003 STA# FB TOC(kg/d) TON(kg/d) NH4(kg/d) Q(m3/s) R^2 = Y=A+B*X+C*X^2+D*X^3 A=-1.20E+000 B = 1.28E+000 C = -2.03E-002 D = 1.67E-004 STA# FB Q(m3/s) R^2 = Y=A+B*X+C*X^2+D*X^3 A = -9.32E-001 B = 5.58E-001 C = -1.61E-002 D = 1.84E-004 STA# FB Q(m3/s) Total P(kg/d) Po4(kg/d) Q(m3/s) Q(m3/s)

28 Flow and Loads at Trout Net Freshwater Inflow Location

29 Water Quality Modeling Issues Algae Dynamics Phosphorous Dynamics Nutrient and Organic Matter Loading Organic Matter Reaction Rates Benthic Algae Sediment Flux Sea Grass

30 WQ Modeling Issues Algae Dynamics Problem: Model Predicted Algae Levels Too Low in Some Areas Investigated Phosphorous Limitations Including DOP Utilization Nutrient Loads Nonlinear vs Linear Predation Nonlinear Predation Provided Most Significant Improvement DOP Utilization and Load Changes Were Not Required Higher Algae Level Improved Prediction of Organic Matter without Significant Changes in Reaction Rates

31 WQ Modeling Issues Loadings and Organic Material Reaction Rates Problems/Questions: Do Potential Loading Uncertainties Contribute to Algae Prediction Problems Influence of Loading and Organic Reaction Rates on Organic Levels Investigate Loading Estimation and Organic Reaction Rates Algae Prediction Improved without Significant Changes in Loading Estimation Higher Algae Level Improved Prediction of Organic Matter without Significant Changes in Reaction Rates

32 WQ Modeling Issues Phosphorous Dynamics Problem/Question: How Does Highly Variable Phosphorous Prediction Relate to Algae Prediction Investigate Best Formulation for Ortho-Phosphorous Sorption and Settling Phosphorous Loads Used Best Estimate of PO4 Partitioning and Suspended Sediment Concentration and Settling to Define Phase Distribution Higher Algae Levels Also Tended to Improve PO4 Prediction Significant Load Changes Were Not Required

33 WQ Modeling Issues Benthic Micro Algae and Sediment Flux Problems/Questions: How Important Are Benthic Micro Algae and Sediment Flux How Does Predicted Flux Compare with Observations Investigate Micro Algae Calibration Benthic Micro Algae Levels Low and Little Data to Evaluate Calibration Sediment Flux Data at Light/Dark Time Scale while Model at Net Time Scale Makes Comparison Difficult

34 Water Quality Model Results and Comparison with Previous WQM Comparison of Model Predicted and Observed Time Series of State Variables at Monitoring Locations Quantify Prediction Performance Using Various Time Series Error Measures Such as Mean, Mean Absolute, RMS, and Fractional MAE Compare Quantitative Measures with Previous Model and WQM s for Other Water Bodies Previous Model Lumped in Space and Time For the Current Model Presented Errors Measures Include Combinations of Point to Point Lumped in Space and Time Range of Point to Point Average of Point of Point

35 Comparison of Mean Absolute Errors Variable COE WQ Model Lumped over all Stations Current WQ Model Averaged over 35 Stations Temperature Salinity Algae Chlorophyll (ug/l) Total Organic Carbon (mg/l) Total Nitrogen (mg/l) Ammonium (mg/l) Nitrate (mg/l) Total Phosphorous (mg/l) Phosphate (mg/l) Dissolved Oxygen (mg/l)

36 Visual Comparison By Region of Bay Using Specific Monitoring Locations Results For Northern Transition Joe Bay FB10 Eastern Duck Key FB9 Central Whipray FB13 Western Johnson FB17 Atlantic Transition Porpoise Lake - FB21 Gulf Transition East Cape FB25 Post Processor Provides Results for 35 Location

37 Calibration Zones for COE WQ Model

38 North Transition Zone Chlorophyll a (10)

39 Eastern Zone Chlorophyll a (9)

40 Central Zone Chlorophyll a (13)

41 Western Zone Chlorophyll a (17)

42 Atlantic Transition Zone Chlorophyll a (21)

43 Gulf Transition Zone Chlorophyll a (25)

44 North Transition Zone TOC (10)

45 Eastern Zone TOC (9)

46 Central Zone TOC(13)

47 Western Zone TOC (17)

48 Atlantic Transition Zone TOC (21)

49 Gulf Transition Zone TOC (25)

50 North Transition Zone TN (10)

51 Eastern Zone TN (9)

52 Central Zone TN (13)

53 Western Zone TN (17)

54 Atlantic Transition Zone TN (21)

55 Gulf Transition Zone TN (25)

56 North Transition Zone NH4 (10)

57 Eastern Zone NH4 (9)

58 Central Zone NH4 (13)

59 Western Zone NH4 (17)

60 Atlantic Transition Zone NH4 (21)

61 Gulf Transition Zone NH4 (25)

62 North Transition Zone TP (10)

63 Eastern Zone TP (9)

64 Central Zone TP (13)

65 Western Zone TP (17)

66 Atlantic Transition Zone TP (21)

67 Gulf Transition Zone TP (25)

68 North Transition Zone PO4 (10)

69 Eastern Zone PO4 (9)

70 Central Zone PO4 (13)

71 Western Zone PO4 (17)

72 Atlantic Transition Zone PO4 (21)

73 Gulf Transition Zone PO4 (25)

74 Comparison of EFDC Lumped Species Sea Grass Model with the FBSG Model FBSG Model Results Shown Below

75 EFDC SG Model Rankin

76 EFDC SG Model Little Maderia

77 EFDC SG Model Duck

78 EFDC SG Model Rabbit

79 Whipray Basin Primary Production and Nutrients

80 Summary and Future Directions Directly Coupled Public Domain EFDC Based Water Quality Model Configured for Calibration to Date Has Demonstrated WQ Model Performance At Level of Previous Model The Model Including Inputs, Post- Processor and Results Is Available Additional Processes Enhancements and Calibration Are Required

81 Summary and Future Directions Forcing Function and Processes Enhancements Phosphorous Dynamics Fully Equivalent Embedded Sea Grass Model Refined Load Estimation Additional Calibration Alternate Calibration Measures Research Level Model Development to Compliment Management Tool Driven Development

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83 Final Salinity Calibration Station Med Resol RMSE Coarse Resol RMSE Med Resol RMSEs Coarse Resol RMSEs Med Resol RMSEu Coarse Resol RMSEu Med Resol IA Coarse Resol IA Bob Allen Buoy Key Butternut Duck Key Garfield Johnson Lt Maderia Lt Rabbit Murray Peterson Terrapin Trout Whipray

84 North Transition Zone Chlorophyll a (10)

85 Eastern Zone Chlorophyll a (9)

86 Central Zone Chlorophyll a (13)

87 Western Zone Chlorophyll a (17)

88 Atlantic Transition Zone Chlorophyll a (21)

89 Gulf Transition Zone Chlorophyll a (25)

90 Outer Keys Zone Chlorophyll a (294)

91 Southwest Shelf Chlorophyll a (369)

92 North Transition Zone TOC (10)

93 Eastern Zone TOC (9)

94 Central Zone TOC(13)

95 Western Zone TOC (17)

96 Atlantic Transition Zone TOC (21)

97 Gulf Transition Zone TOC (25)

98 Outer Keys Zone TOC (294)

99 Southwest Shelf TOC (369)

100 North Transition Zone TN (10)

101 Eastern Zone TN (9)

102 Central Zone TN (13)

103 Western Zone TN (17)

104 Atlantic Transition Zone TN (21)

105 Gulf Transition Zone TN (25)

106 Outer Keys Zone TN (294)

107 Southwest Shelf TN (369)

108 North Transition Zone NH4 (10)

109 Eastern Zone NH4 (9)

110 Central Zone NH4 (13)

111 Western Zone NH4 (17)

112 Atlantic Transition Zone NH4 (21)

113 Gulf Transition Zone NH4 (25)

114 Outer Keys Zone NH4 (294)

115 Southwest Shelf NH4 (369)

116 North Transition Zone NOx (10)

117 Eastern Zone NOx (9)

118 Central Zone NOx (13)

119 Western Zone NOx (17)

120 Atlantic Transition Zone NOx (21)

121 Gulf Transition Zone NOx (25)

122 Outer Keys Zone NOx (294)

123 Southwest Shelf NO3 (369)

124 North Transition Zone TP (10)

125 Eastern Zone TP (9)

126 Central Zone TP (13)

127 Western Zone TP (17)

128 Atlantic Transition Zone TP (21)

129 Gulf Transition Zone TP (25)

130 Outer Keys Zone TP (294)

131 Southwest Shelf TP (369)

132 North Transition Zone PO4 (10)

133 Eastern Zone PO4 (9)

134 Central Zone PO4 (13)

135 Western Zone PO4 (17)

136 Atlantic Transition Zone PO4 (21)

137 Gulf Transition Zone PO4 (25)

138 Outer Keys Zone PO4 (294)

139 Southwest Shelf PO4 (369)