2002 Progress Report: Assessment of the Consequences of Climate Change on the South Florida Environment

EPA Grant Number: R827453
Title: Assessment of the Consequences of Climate Change on the South Florida Environment
Investigators: Harwell, Mark A. , Ault, Jerald S. , Cropper, Wendell P. , Gentile, John H. , Letson, David , Lirman, Diego , Luo, Jiangang , Wang, John
Institution: University of Miami , Center for Marine and Environmental Analyses , Rosenstiel School of Marine and Atmospheric Science
Current Institution: University of Miami
EPA Project Officer: Hiscock, Michael
Project Period: October 1, 1999 through September 30, 2002 (Extended to September 30, 2003)
Project Period Covered by this Report: October 1, 2001 through September 30, 2002
Project Amount: $889,579
RFA: Integrated Assessment of the Consequences of Climate Change (1999) RFA Text |  Recipients Lists
Research Category: Global Climate Change , Ecological Indicators/Assessment/Restoration , Water , Ecosystems , Climate Change

Objective:

This research project involved a multidisciplinary team of researchers led by the Center for Marine and Environmental Analyses (CMEA) at the University of Miami, collaborating with the South Florida Water Management District (SFWMD) and the U.S. Geological Survey (USGS). The objective was to conduct an ecological risk assessment to evaluate the potential effects of changes in precipitation and freshwater deliveries caused by climate change and by the Comprehensive Everglades Restoration Plan (CERP) on ecological systems of the South Florida landscape. A suite of linked simulation models are being developed to simulate and evaluate potential impacts on the: (1) regional surface and groundwater hydrology; (2) abundance and distribution of wading birds within the Florida Everglades; (3) freshwater inputs into Biscayne Bay and associated salinity fields; (4) seagrass and hardbottom community productivity and distribution; and (5) population dynamics and stock abundance of estuarine fish.

Progress Summary:

The hydrology of South Florida is controlled by an extensive system of canals, levies, and water control structures that regulate freshwater flows across the landscape. Direct links were created from outputs of the hydrological models: the South Florida Water Management Model (SFWMM), developed by the SFWMD to describe overland and groundwater flow dynamics for the region, and the Biscayne Bay hydrodynamic model, developed at CMEA. Similarly, the Biscayne Bay hydrodynamic model was linked to a series of ecological models developed at CMEA that describe the population dynamics of segrasses, sponges, and fisheries resources. In addition, the outputs from the SFWMM were used as inputs to the Across-Trophic Level System Simulation, developed by the USGS, to simulate effects on the long-legged and short-legged wading birds of the Everglades. The seamless modeling framework, developed with the support of the U.S. Environmental Protection Agency (EPA) Global Change Research Program (see Figure 1), enables us to directly simulate the effects of water management scenarios, as well as different climate change scenarios on the hydrology of South Florida, and to evaluate the potential effects of these scenarios on important ecological and economic endpoints of Biscayne Bay and the Everglades.

Figure 1. CMEA modelling framework used to assess the potential impacts of Climate Change and the Everglades Restoration Project on the biological endpoints of the South Florida landscape.

The basis for our approach was the ecological risk assessment framework developed for the EPA. A scenario-consequence analysis approach was used, in which paired scenarios were developed to characterize the effects on selected ecological endpoints from changes in precipitation caused by climate variability, from implementation of the CERP project, or from both. Our assessment was conducted as a sensitivity analysis, where a realistic, plausible range of climatic conditions was explicitly simulated and tested. The following simulation scenarios were developed using historical precipitation and temperature data, based on the 1965-1995 record available for South Florida, modified by a set of global climate change scenarios developed at a climate change scenario workshop:

  • 2050 BASE/D13R (CERP water management scenario, no climate change).
  • 2050 BASE/D13R and 25 percent increase in rainfall (CERP plus climate change).
  • 2050 BASE/D13R and 25 percent decrease in rainfall (CERP plus climate change).
  • 2050 BASE/D13R and 2°C increase (CERP plus climate change).

    Precipitation values were uniformly changed within each cell of the SFWMM. Similarly, the temperature scenario was used to modify the ET values of each cell. The output from the SFWMM, expressed as daily freshwater flows into Biscayne Bay from canal, overland, and groundwater sources, provided input for the Biscayne Bay hydrodynamic model. The hydrodynamic model provided input, expressed as daily salinity values, for the SEASCAPE model of benthic communities of Biscayne Bay. A Fish Trophodynamics Model, a spatial age structured predator-prey model, also was developed to assess seatrout (Cynoscion nebulosus) population risks from exploitation and environmental changes. The SEASCAPE model (100,000 grid cells, 100 m x 100 m) was used to simulate the impacts of the scenarios on seagrasses and sponges of Biscayne Bay. Lastly, the impacts of the scenarios were simulated by predicting habitat suitability for wading birds across the Everglades landscape using the Across Trophic Level Simulation System (ATLSS) model.

    Results. The results from the simulations indicate that interannual variability in precipitation is a dominant driver in South Florida, significantly affecting many of the ecological endpoints for Biscayne Bay and the Everglades. Major changes in canal, overland, and groundwater flows into coastal bays can result from climate change-induced modifications in precipitation. These changes in freshwater flows can lead to significant differences in the salinity fields within Biscayne Bay, as simulated in this project. Areas where canal influences are prevalent (i.e., central bay) can experience significant reductions in mean salinities for extended periods of time under "wet" scenarios, while areas with restricted circulation (i.e., southern bay) can experience periods of hypersalinity (> 40 ppt) under "dry" conditions. In contrast, minor changes in salinity patterns were simulated for those areas in eastern Biscayne Bay, where oceanic influences prevail.

    Increased freshwater delivery to Biscayne Bay, simulated under the increased precipitation scenarios, can damage populations of obligate marine sponges in western Biscayne Bay by increasing the frequency of low-salinity events. Similarly, reduced salinity can influence growth and abundance seagrass communities. Species such as Thalassia testudinum that are more susceptible to reduced salinity could be lost or out-competed from present locations, and replaced by less-susceptible species like Halodule wrightii.

    The simulated precipitation scenarios also influence habitat quality for wading birds within the Everglades. As expected, an increase of 25 percent in precipitation during a dry year increases the spatial extent of suitable habitat for long-legged wading birds, such as wood storks and snowy egrets, and short-legged birds, such as white ibis and great blue herons. In contrast, the extreme conditions simulated (decreases in precipitation during dry years and increases in precipitation during wet years) have significant negative impacts on the foraging habitat for wading birds in the Everglades. Of special concern are the extreme dry conditions that significantly reduce both the quality and the spatial extent of suitable wading bird habitat.

    Future Activities:

    Future activities are to complete our assessment of the potential impacts of the climate change scenarios on the chosen endpoints. We also will work on the completion and analyses of all model runs, as well as the incorporation of the final component, the economic model, into our simulation framework.


    Journal Articles on this Report : 9 Displayed | Download in RIS Format

    Other project views: All 17 publications 9 publications in selected types All 9 journal articles
    Type Citation Project Document Sources
    Journal Article Biber PD, Harwell MA, Cropper, Jr. WP. Modeling the dynamics of three functional groups of macroalgae in tropical seagrass habitats. Ecological Modeling (accepted, 2003). R827453 (2002)
    R827453 (Final)
    R828677C004 (2003)
    not available
    Journal Article Cropper WP, Lirman D, Tosini SC, DiResta D, Luo J, Wang J. Population dynamics of a commercial sponge in Biscayne Bay, Florida. Estuarine Coastal and Shelf Science 2001;53(1):13-23. R827453 (2001)
    R827453 (2002)
    R827453 (Final)
  • Full-text: sciencedirect
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  • Abstract: sciencedirect
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  • Journal Article Gentile JH, Harwell MA, Cropper W, Harwell CC, DeAngelis D, Davis S, Ogden JC, Lirman D. Ecological conceptual models: a framework and case study on ecosystem management for South Florida sustainability. Science of the Total Environment 2001;274(1-3):231-253. R827453 (2001)
    R827453 (2002)
    R827453 (Final)
  • Abstract from PubMed
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  • Journal Article Irlandi E, Orlando B, Macia S, Biber P, Jones T, Kaufman L, Lirman D, Patterson E. The influence of freshwater runoff on biomass, morphometrics, and production of Thalassia testudinum. Aquatic Botany 2001;72(1):67-78. R827453 (2001)
    R827453 (2002)
    R827453 (Final)
  • Full-text: sciencedirect
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  • Abstract: sciencedirect
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  • Journal Article Lirman D, Manzello D, Macia S. Back from the dead: the resilience of Siderastrea radians to severe stress. Coral Reefs 2002;21(3):291-292. R827453 (2002)
    R827453 (Final)
    not available
    Journal Article Lirman D, Orlando B, Macia S, Manzello D, Kaufman L, Biber P, Jones T. Coral communities of Biscayne Bay, Florida and adjacent offshore areas: diversity, abundance, distribution, and environmental correlates. Aquatic Conservation-Marine and Freshwater Ecosystems 2003;13(2):121-135. R827453 (2001)
    R827453 (2002)
    R827453 (Final)
  • Abstract: interscience
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  • Journal Article Lirman D, Cropper WP. The influence of salinity on seagrass growth, survivorship, and distribution within Biscayne Bay, Florida: Field, experimental, and modeling studies. Estuaries 2003;26(1):131-141. R827453 (2001)
    R827453 (2002)
    R827453 (Final)
  • Full-text: springerlink
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  • Abstract: springerlink
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  • Journal Article Manzello D, Lirman D. The photosynthetic resilience of Porites furcata to salinity disturbance. Coral Reefs 2003;22(4):537-540. R827453 (2002)
    R827453 (Final)
    not available
    Journal Article Wang JD, Luo JG, Ault JS. Flows, salinity, and some implications for larval transport in South Biscayne Bay, Florida. Bulletin of Marine Science 2003;72(3):695-723. R827453 (2001)
    R827453 (2002)
    R827453 (Final)
  • Full-text: ingentaconnect
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  • Abstract: ingentaconnect
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  • Supplemental Keywords:

    watershed, regional hydrology, canal discharge, groundwater, overland flow, precipitation, marine, estuarine, coastal lagoon, seagrasses, sponges, fishes, shrimp, fisheries resources, stressor, exposure, ecological endpoints, ecological effects, ecosystem vulnerability, ecosystem, indicator, restoration, aquatic, habitat, integrated assessment, simulation modeling, management decision support, conservation, socioeconomic models, fisheries, aquatic ecology, benthic ecology, ecological modeling, population models, hydrodynamics models, regional hydrological models, Southeastern United States, Florida, Everglades, Biscayne Bay, Miami, Florida, FL., RFA, Scientific Discipline, Air, Geographic Area, Ecosystem Protection/Environmental Exposure & Risk, Hydrology, Ecology, Ecosystem/Assessment/Indicators, climate change, State, Ecological Risk Assessment, Ecology and Ecosystems, risk assessment, South Florida, Florida Everglades, recreational fisheries, environmental monitoring, flood control, human activities, watershed, hydrologic models, agriculture, water quality, coastal ecosystems, estuarine ecosystem, fuel spills, Florida, climate variability, FLA

    Relevant Websites:

    http://141.232.1.11/org/pld/restudy/hpm/index.html Exit
    http://www.atlss.org Exit

    Progress and Final Reports:

    Original Abstract
  • 2000 Progress Report
  • 2001 Progress Report
  • Final Report