Grantee Research Project Results
2001 Progress Report: Assessment of the Consequences of Climate Change on the South Florida Environment
EPA Grant Number: R827453Title: Assessment of the Consequences of Climate Change on the South Florida Environment
Investigators: Harwell, Mark A. , Letson, David , Lirman, Diego , Luo, Jiangang , Wang, John , Gentile, John H. , Cropper, Wendell P. , Ault, Jerald S.
Institution: University of Miami
EPA Project Officer: Packard, Benjamin H
Project Period: October 1, 1999 through September 30, 2002 (Extended to September 30, 2003)
Project Period Covered by this Report: October 1, 2000 through September 30, 2001
Project Amount: $889,579
RFA: Integrated Assessment of the Consequences of Climate Change (1999) RFA Text | Recipients Lists
Research Category: Aquatic Ecosystems , Ecological Indicators/Assessment/Restoration , Water , Climate Change
Objective:
The objective of this research project is to evaluate the potential effects of climate change-induced alterations in precipitation regime on ecological systems of the South Florida landscape. A series of linked simulation models were developed by CMEA researchers and collaborators to simulate and evaluate the potential impacts of changes in precipitation on: (1) the regional surface and groundwater hydrology; (2) the abundance and distribution of wading birds within the Florida Everglades; (3) freshwater inputs into coastal estuaries and associated salinity fields; (4) seagrass and hardbottom community productivity and distribution; and (5) population dynamics and stock abundance of estuarine fish.
Progress Summary:
One of the initial accomplishments of our second year of activities was the convening of a workshop with climate change scientists and regional experts at the University of Miami. The goal of this meeting was to characterize precipitation patterns within the South Florida landscape, and determine a relevant set of climate change scenarios to be simulated by our modeling framework. The main conclusions from this meeting were:
· The climate of South Florida is characterized by large intra- and inter-annual variability in precipitation patterns, a wet season from May to October, with nearly 75 percent of yearly precipitation, and periodic extreme events such as freezes, tropical storms, floods, and droughts.
· Predicting precise future precipitation patterns for South Florida would be very difficult. Much of the uncertainty associated with predicting climate change effects on the Florida peninsula comes from the large oceanic influence that is not well resolved for the region. In addition, the spatial scales of GCMs are not adequate to describe climatic patterns at this scale. A clear example of these difficulties can be seen in the conflicting predictions offered by the leading GCMs. While the Hadley Model predicts a decrease in precipitation under climate change scenarios, the Canadian Model predicts an increase in annual precipitation for the region. The influence of periodic climatic events such as El Nino/Southern Oscillation, as well as tropical storms, restrict the long-term predictive capabilities of these models.
Faced with these uncertainties, it was concluded that our assessment would be conducted as a sensitivity analysis, where a realistic, possible range of conditions would be tested. Accordingly, the simulation scenarios would be developed using historical precipitation and temperature data, based on the 1965-1995 record available for South Florida, modified by the set of global climate change scenarios. Both the current (2050 BASE) and preferred (D13R) water management scenarios of the Comprehensive Everglades Restoration Project would be modeled explicitly for each of the following climate change scenarios:
(1,2) 2050 BASE/D13R (management scenarios)-No Climate Change
(3,4) 2050 BASE/D13R and 25 percent increase in rainfall all months-GCC plus
(5,6) 2050 BASE/D13R and 25 percent decrease in rainfall all months-GCC minus
(7,8) 2050 BASE/D13R and 2°C increase all months-GCC plus.
The output from the South Florida Water Management Model, expressed as daily freshwater flows into Biscayne Bay from canal, overland, and groundwater sources, will provide input for CMEA's Biscayne Bay hydrodynamics model for each scenario. The hydrodynamics model will provide input, expressed as daily salinity values for Biscayne Bay, for the SEASCAPE Model for seagrasses and sponges of Biscayne Bay. In addition, two new components were added to our modeling framework during the past year, the Fish Trophodynamics and the Across Trophic Level System Simulation (ATLSS) Models.
Fish Trophodynamics Model. Because spotted seatrout (Cynoscion nebulosus ) are sensitive indicators of environmental system changes, we developed a spatial age structured predator-prey model to assess seatrout population risks from exploitation and environmental changes. The model is configured to quantify the dynamics of changes in productivity resulting from exploitation and water management strategies, as well as changes in precipitation.
ATLSS Model. As part of this project, we will evaluate the potential ecological impacts of the proposed climate change scenarios and water management regimes on the foraging activity of wading birds within the Florida Everglades using the ATLSS. The ATLSS Model uses knowledge of the effect of hydrologic factors and the concentration and availability of food resources during the breeding season to compute a Foraging Conditions Index (FCI) for wading birds. The FCI is a composite index of spatial and temporal patterns that expresses the effects of hydrologic scenarios as changes in the spatial pattern of foraging potential over the model area. The FCI is designed to evaluate whether the appropriate hydrologic conditions for successful wading bird feeding are present during the time period that includes nest initiation, feeding of young, and fledging of young. The primary criteria used in the index are the: (1) occurrence of water in a specific depth range for short-legged birds, such as white ibis and great blue herons, and long-legged birds, such as wood storks and snowy egrets, and (2) length of continuous periods of food availability.
The CMEA models will be run under the precipitation scenarios chosen during
our climate change workshop to answer the following questions:
1. Will climate change alter the volumes, timing, and distribution of water
resources throughout the South Florida system?
2. Will those changes have a significant impact on ecological and economic systems?
Although the simulation runs have not been completed, some preliminary results can be highlighted at this time:
o Precipitation is a major driver within the South Florida landscape.
o Climate change-induced precipitation changes (± 25 percent) can lead to significant changes in the salinity dynamics of coastal bays.
o Water management structures influence spatial and temporal distribution of impacts of precipitation changes.
o Water management systems are potentially able to lessen the impacts of climate change- induced precipitation changes.
o Sponges in Biscayne Bay are very susceptible to increases in precipitation that reduce mean salinity and increase the frequency of low-salinity events.
o A 25 percent increase in precipitation can result in a 15-50 percent reduction in sponge population size.
o Decreases in precipitation will benefit marine sponges by increasing mean salinity and reducing the frequency of low-salinity peaks.
o Simulated climate change scenarios (± 25 percent precipitation, + 2°C) had mainly negative effects on above-ground biomass of the dominant seagrass species in Biscayne Bay, Thalassia testudinum. However, effects are localized and influenced by water management practices.
o Under persistent changes, species that are susceptible to low salinity, such as Thalassia, could be lost and/or outcompeted, and even replaced by less susceptible species like Halodule.
o Loss of productivity and essential habitat may lead to major changes in the food chain (e.g., shrimp, fish) and loss of important commercial resources.
Future Activities:
During the final period of this project, we will complete our assessment of the potential impacts of the climate change scenarios on the chosen endpoints. Future activities include 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 : 6 Displayed | Download in RIS Format
| Other project views: | All 17 publications | 10 publications in selected types | All 10 journal articles |
|---|
| Type | Citation | ||
|---|---|---|---|
|
|
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) |
Exit Exit |
|
|
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) |
Exit |
|
|
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) |
Exit Exit |
|
|
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) |
Exit |
|
|
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) |
Exit Exit |
|
|
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) |
Exit Exit |
Supplemental Keywords:
watershed, regional hydrology, canal discharge, groundwater, overland flow, precipitation, marine, estuarine, coastal lagoon, segrasses, 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, GIS, hydrodynamics models, regional hydrological models, Southeastern U.S., Florida, Everglades, Biscayne Bay, Miami, FL., RFA, Air, Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Geographic Area, Ecological Risk Assessment, State, Ecology, Ecosystem/Assessment/Indicators, Hydrology, climate change, Ecology and Ecosystems, flood control, FLA, recreational fisheries, hydrologic models, water quality, Florida, Global Climate Change, coastal ecosystems, risk assessment, environmental monitoring, climate variability, estuarine ecosystem, human activities, agriculture, Florida Everglades, South Florida, watershedRelevant Websites:
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.