South Florida
Hydrology and Salinity Models
·
Evaluation
of hydrology and salinity models for Everglades
·
Each
model scored according to accepted model performance criteria
·
Complex
numeric models were least portable and hardest to use, though they supply much
greater detail
·
Empirical
models were easiest to use and less-expensive to run with less detail in the
output
ABSTRACT
This study evaluated the hydrology and
salinity models being used for Everglades restoration. Each model that was
reviewed was assigned a series of scores for achieving the modeling criteria,
with 5 being the highest score (excellent).
The widest ranges of scores were for portability and ease-of-use
reflecting the constraints of model sophistication. The narrowest range of scores was associated
with validity – most of these models have withstood the test of use and have
been developed, reviewed, and updated to a point of application-ready
acceptance.
In
general, the most complex models (SWMM, RSM, FTLOADDS, EFDC Florida Bay, Wang
et al. (2003) Biscayne Bay, TABS MDS Biscayne Bay) are the least portable, are
rated lowest for ease of use, and did not score as high on validity as did the
models that are less complex (linear regression models for stage and flow, MLR
salinity models, FATHOM, Four Box Model Florida Bay, Biscayne Bay Box
Model).
Temporal
coverage was best for the regression models because they are daily time step
models and can be run for the longest periods of time. For spatial coverage, none of the models
covers the full domain of the south Florida coastal system but most model
domains cover the region(s) of focus.
The
least expensive models to employ are the least sophisticated statistical models
and box models. The use of grid-domain
freshwater models covering a large region such as the spatial domain of the
SFWMM and RSM will always require more budget than the freshwater ecosystem
statistical and box models by a substantial amount. However, there are important transport, exchange,
and circulation questions in the connected Everglades freshwater and estuarine
system that requires a very high level of resolution, justifying the use of
more sophisticated models.
Table ES-1: Summary of General Information on Hydrology and Salinity Models Currently in Use in South Florida.
Model Name |
Model Type |
Simulated Parameters |
Spatial Domain |
Grid Size |
Simulation temporal domain |
Relevant Time Step |
Linear Regression Models |
Statistical |
Stage, Flow |
Everglades |
N/A |
1965-2000 |
daily |
PHAST |
Wetland Basin |
Flow |
Everglades and Mangrove Zone |
regional |
1965-2000 |
monthly |
SFWMM |
Freshwater Hydrology |
Stage, Flow |
Everglades |
3.2km X 3.2km |
1965-2000 |
daily |
RSM |
Freshwater Hydrology |
Stage, Flow |
Everglades |
variable |
1965-2000 |
daily |
ENPMod1 |
Freshwater Hydrology |
Stage, Flow |
Everglades |
3.2km X 3.2km |
1965-2000 |
daily |
MLR |
Statistical |
Salinity |
FL Bay, WW Bay, SW Gulf coast, Manatee Bay, Barnes Sound |
N/A |
1965-2000 |
daily |
Four Box Florida Bay |
Mass Balance |
Salinity |
Florida Bay |
regional |
1993-1998 |
monthly |
Biscayne Bay Box Model |
Mass Balance |
Salinity, nutrients |
Biscayne Bay |
box, variable |
1993-2007 |
monthly |
FATHOM |
Mass Balance |
Salinity, nutrients |
Florida Bay, Manatee Bay, Barnes Sound |
open-water basins |
1970-2000 |
monthly |
FTLOADDS TIME/TTI |
2D/3D Coupled surface and groundwater |
Stage, Flow, Salinity |
Everglades, northern Florida Bay, SW Gulf coast, TTI |
0.5km X 0.5km |
|
daily |
EFDC |
3-D Hydrodynamic |
Salinity |
Florida Bay |
variable |
1997-2000 |
daily |
Wang et al., 2003 Biscayne Bay |
3-D Hydrodynamic |
Salinity |
Biscayne Bay |
variable |
1995-1999 |
daily |
TABS MDS Biscayne Bay |
3-D Hydrodynamic |
Salinity |
Biscayne Bay |
variable |
|
daily |
Table ES-2: Summary of scoring for south Florida hydrology and salinity models using the model evaluation criteria. Score is from 1 = lowest to 5 = highest. No scores are provided for the category of model focus because all of the models satisfy the requirement that the output be relevant to ecosystem attributes.
Model |
Parameters simulated |
Portability |
Validity |
Fidelity |
Focus |
Ease of Use |
Temporal Coverage |
Spatial Coverage |
Linear regression models for stage |
stage |
3 |
4 |
2 |
- |
5 |
5 |
3 |
PHAST |
flow |
2 |
4 |
2 |
- |
5 |
4 |
2 |
SFWMM |
stage, flow |
3 |
4 |
4 |
- |
4 |
4 |
4 |
RSM |
stage, flow |
1 |
5 |
4 |
- |
1 |
5 |
4 |
MLR |
salinity |
5 |
5 |
2 |
- |
5 |
5 |
3 |
Four Box Florida Bay |
salinity |
2 |
5 |
3 |
- |
4 |
4 |
3 |
Biscayne Bay Box Model |
salinity |
3 |
5 |
3 |
- |
4 |
4 |
3 |
FATHOM Florida Bay |
salinity |
4 |
5 |
4 |
- |
4 |
4 |
3 |
FTLOADDS TIME / BISECT / TTI |
stage, flow, salinity |
3 |
4 |
5 |
- |
3 |
3 |
4 |
EFDC Florida Bay |
salinity |
1 |
4 |
5 |
- |
2 |
2.5 |
3 |
Wang et al., (2003) Biscayne Bay |
salinity |
3 |
4 |
4 |
- |
3 |
2.5 |
3 |
TABS MDS Biscayne Bay |
salinity |
1 |
4 |
5 |
- |
1 |
2.5 |
3 |