Kevin Kotun (ENP)
The TIME Model Development project is focused on further developing, extending and implementing a mathematical model to study the interaction between wetland sheet flows and dynamic forces in the transition zone between the southern Everglades and its coastal embayments. The model will be used to study and evaluate the combined response of hydroperiods in the wetlands and salinities in the mangrove ecotone to inflow alterations.
The major product of the TIME Model Development project will be a sound, physically-based, fine-resolution (500m) model of the Everglades National Park area of the Everglades consistent with the Across Trophic Level System Simulation models that can be used as a research tool and management model to study and evaluate ecosystem response to regulatory decisions. Through analysis of model results for varied inflows, cause and effect relationships to ecosystem functions and sustainability can be investigated to evaluate and guide restoration actions. Any external dynamic factors that could adversely affect restoration objectives can be identified and demonstrated. Data collected in support of the model development will be made available for dissemination via the Internet and scientific findings will be reported in traditional peer-reviewed literature as appropriate.
Both regulatory and natural factors contribute to the definition of hydroperiods and salinities, making their precise evaluation and management difficult. The understanding and control of hydroperiods and salinities becomes even more problematic in the mangrove ecotone, the transition zone between the Everglades wetlands and coastal embayments where hydroperiods and salinities are inextricably linked and the mixing of fresh and salt water cannot be ignored. In this region, coastal tides, wetland flows and upstream inflows must be considered concurrently for an accurate understanding of their effects.
Project personnel include: Ami Riscassi, Gordon Anderson, Vince Caruso, Ed Cyran, Maria Deszcz-Pan, Pat Gammon, David Garces, Bob Glover, Chuck Henkle, Sandra Kinnaman, Jim Krest, Al Lombana, Nancy Rybicki, Dan Sechrist, Gordon Shupe, Eddie Simonds, Lars Soderqvist, Marc Stewart, Jean-Claude Thomas, Jessica Thomas, Craig Thompson, Christa Walker, Kevin Whelan, Melinda Wolfert, and Mark Zucker.
Duff, M. P.
Bhatt, T. N. Fennema, R. J. Fitterman, D. V.
Schaffranek, R. W.
Ruhl, H. A. Hansler, M. E.
The model will also be modified to accept hourly time-dependent wind data and to calculate time- and space-dependent wind stress. These data will be interpolated from data archived in the TIME Data System. The model has been modified already to use a wind sheltering coefficient to calculate wind stress based on wind speed, the equivalent wind stress over unvegetated waters and a constant sheltering coefficient from the literature. This formulation will be refined to allow for spatial variation in the sheltering coefficient based on assignment of grid cells using John Jones' vegetation mapping data as input. Assignment will be based on findings from Jenter and Duff (1999) and from information derived from analysis of simultaneously deployed meteorological towers and profiling current meters at two locations within the Everglades: one in Water Conservation Area 3A and one in southern Shark Slough. These sites will be maintained and the data analyzed in order to apply the analysis to the wind sheltering specification in the model. These sites were installed in FY2002 and are expected to yield extremely useful information for the TIME modeling effort.
A secondary goal in FY2003 will be to assure that the entire TDS database from 1995 to present is quality assured and as complete as possible. Each of the over 200 datasets in the TDS will be reviewed. USGS personnel work closely with Everglades National Park personnel to ensure that the NPS data sets in the TDS are as up-to-date as possible. The web interface for the TDS will be modified to allow a simple and concise report of data completeness to be produced for arbitrarily specified time periods. The data-extraction scripts of the TDS will be modified to offer interpolation of missing data so the user can receive a gap-free dataset which can be more easily used as model input or for other purposes.
Incorporation of vegetative resistance and meteorological effects in to the TIME surface-water model
1. Modification of the SWIFT2D computer code will be made to best simulate vegetative resistance to flow. This will be part of finalization of code modifications to the SWIFT2D configuration applicable to the TIME modeling domain. Vegetative resistance code changes will be based on the published work of J. Lee et al. and Lee, Lai and Jenter. Statistical correlations between depth-averaged velocity data and depth-averaged vegetation data appear to be a potential link between the vegetative resistance work to date and the vegetative mapping work of John Jones. As such, this linkage will be incorporated into SWIFT2D to the extent possible.
Additionally, final code changes for meteorological forcing inputs will be completed. These will include code modifications for the acceptance of variable wind and NEXRAD rainfall fields. In order to prepare the TIME surface-water model for potential use in future scenario testing, the TIME Data System will be modified to automatically extract and format user-selected data for model input. SWIFT2D’s input processor will be modified to accept these automatically formatted data. Refinement of wind forcing and precipitation forcing algorithms in the model will be completed. These algorithms will be based partially on correlations derived from simultaneous wind and velocity measurements collected during this and previous rainy seasons.
2. Assembly , storage, and distribution of time-variable datasets for surface water modeling
The TIME Data System (TDS) will be finalized. All data sets for the time period January 1, 1995 through June 1, 2003 will be archived quality assured. All tools for extracting, viewing, analyzing, archiving and reformatting data for the TDS will be finalized. Final publication of a User’s Manual for the TDS will occur in FY2004. The TDS will be packaged in such a way that it can be directly transferred with the finalized version of SWIFT2D for future scenario testing.
The TIME project website, <http://time.er.usgs.gov> will be maintained through FY2004 as a gateway for TIME project and other South Florida researchers to download data from the TDS and TIME project reports.
U.S. Department of the Interior, U.S. Geological Survey, Center for
Coastal Geology
Comments and suggestions? Contact: Heather
Henkel - Webmaster
Generated by mp version 2.7.33 on Tue Jun 22 10:17:47 2004