Study Title: Tides and Inflows in the Mangroves of the Everglades (TIME) Model Development
Study Start Date: 10/1/99 Study End Date: 9/30/04
Web Sites: http://time.er.usgs.gov
Location (Subregions, Counties, Park or Refuge): Everglades National Park, Big Cypress National Preserve
Funding Source: USGS's Greater Everglades Science Initiative (PBS)
Principal Investigator(s): Harry L. Jenter, hjenter@usgs.gov
Project Personnel: Cheryl Lee (Environmental Careers Organization intern)
Supporting Organizations: National Park Service Everglades National Park
Associated / Linked Projects: Schaffranek, Langevin, Swain, Jones
Overview & Objective(s):
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.
Status:
FY2004 was the last funded year of this project. Two major personnel changes occurred during FY2004 which affected the research and publication strategy for this project: 1) Cheryl Lee, a recently hired intern for the project, resigned abruptly without notice during the first week of the fiscal year and efforts to replace her were unsuccessful 2) Harry Jenter, the project chief, was appointed Acting Assistant Branch Chief for BRR-ER in the 7th month of the fiscal year, then Assistant Branch Chief in the 11th month of the fiscal year. Thus, the majority of the work for this fiscal year was performed by Jenter in the first 6 months of the year. During this time, the TIME Data System, supported throughout the duration of this project was handed over to the Miami Subdistrict Office and training was provided to Melinda Wolfert in its operation and maintenance. Development of a graphical user interface for the TIME surface-water model was begun, and will be continued (using FY2004 funds remaining from Cheryl Lee's unfulfilled internship) if a suitable intern can be found in FY2005. Analysis of meteorological and tidal records was conducted in collaboration with Ray Schaffranek and Ami Riscassi in order to establish appropriate forcing and boundary conditions for the TIME surface-water model. One journal article was published during FY2004 and two journal articles are in revision for resubmission in FY2005.
Recent & Planned Products:
Published:
- Lee, J.K., L.C. Roig, H.L. Jenter and H.M. Visser, 2004, Drag Coefficients for Modeling Flow through Emergent Vegetation in the Florida Everglades, Ecological Engineering, volume 22, 237-248.
Submitted, reviewed and in revision for resubmission:
- Lee, J.K., V.C. Lai and H.L. Jenter. A Pipe-manometer Method for Determining Wetland Water-Surface Slope. Submitted to American Society of Civil Engineers, Journal of Hydraulic Engineering.
- Jenter, H.L., R.W. Schaffranek and T.J. Smith. Thermally-driven Vertical Mixing in the Everglades. Submitted to Wetlands.
Relevance to Greater Everglades Restoration Information
This subset of the TIME project is relevant to USGS Science Plan in Support of Everglades Restoration Science Objectives, Science Objective 1, Get the Hydrology Right (Water quantity, timing and distribution), in particular:
- How do hydropatterns and flow affect the Greater Everglades ecosystem?
- What are the effects of vegetative resistance to flow?
Key Findings:
- Vegetative resistance to flow is directly correlated to two measurable parameters: a Reynolds number based on the average distance between plant stems and the ratio of that same distance to the water depth.
- There is a strong daily periodicity in the vertical profile of temperature throughout the water column, highlighted by a thorough mixing of the topmost 40cm nearly every evening. This periodicity is driven by the air-water temperature difference to the near-complete exclusion of wind and rain effects.
