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Last updated: October 11, 2002
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Part 4: Wind Effects, Boundary and Internal Flows, and Topography and Bathymetry
Wind Effects
Meteorologic, vegetation, and flow data are collected at various locations in Taylor Slough and Florida Bay to determine
the effect of wind on water movement. Wind speed and direction data collected at Old Ingraham Highway, C-111 canal,
and Joe Bay are plotted in the graph below. These data are filtered, interpolated onto the model grid, and input to the
model as a forcing function.
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Wind at 10 m Above Ground
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Graph of wind speed and direction at Joe Bay, C-111 canal, and Old Ingraham Highway. (Click on graph for full-sized version.)
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Wind effects in Florida Bay can produce elevated water levels that impede or even reverse flows in tidal creeks
discharging from Taylor Slough. The plot of measured data, in the graph below, shows one such flow reversal on August
1-3, 1997, in Trout Creek. The sustained period of nearly constant wind speed in the northwest direction that preceded
and caused this flow reversal is evident in the plots of data from the three meteorologic stations. The importance of the
treatment of wind is demonstrated by the improved agreement between measured and simulated flows shown in the
above graph when wind is input to the model as a forcing function.
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Computed and Measured Flows at Trout Creek
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Plot of computer and measured flow. A flow reversal is shown on August 1-3.
(Click on graph for full-sized version.)
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Boundary and Internal Flows
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Flow measurement.
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Water-level, velocity, discharge, and rainfall data are collected in canals,
culverts, wetlands, and tidal creeks throughout the SICS study area for use in
the model. These data are used to define inflows at the model boundaries, to
evaluate empirical coefficients employed in the numerical solution, and to
verify simulation results. Graphs of mean monthly and seasonal flows show
discharge data from five monitoring sites in Florida Bay. Mean flow vectors
in the wetlands of Taylor Slough and along C-111 canal, derived from
velocities measured using portable acoustic Doppler meters, are overlain in
a satellite image for comparison with model results.
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Flow gaging station.
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Mean flow vectors in the wetlands of Taylor Slough.
(Click on photo for full-sized version.)
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Mean Monthly Flows at Major Discharge Areas of Taylor Slough
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Seasonal Flows - May 1997 to April 1998
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(Click on maps above for full-sized version.)
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Topography and Bathymetry
Very accurate data are needed to define the topography of the wetlands and bathymetry of Florida Bay and its coastal
embayments for modeling purposes. High topographic and bathymetric data accuracy is critical for flow simulation due
to the extremely low surface gradient. Grids of evenly spaced elevation data are generated from point values derived
using geodetic-quality differential Global Positioning System (GPS) technology. Gridded elevation data of topography
of the C-111 area and bathymetry of Joe Bay, interpolated to produce these color-coded contours, are fundamental
input to the model. Digital orthophoto quadrangle maps, shown as land cover in the bathymetry illustration, are also used
for flow interpretation.
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Bathymetry
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Global Positioning System (GPS)
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Topography
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Next: Evaporation and Plant Transpiration,
Saltwater Intrusion, Ground-water Exchange, and Water Quality
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