Grantee Research Project Results
2004 Progress Report: Modeling the Impacts of Climate Change on Wetland Ecosystems
EPA Grant Number: R829420E04Title: Modeling the Impacts of Climate Change on Wetland Ecosystems
Investigators: Aravamuthan, Vibhas , Singh, Vijay P. , Koppelman, David , Thiagarajan, Ganesh , Ramanujam, Jagannathan , Twilley, Robert
Current Investigators: Aravamuthan, Vibhas , Suhayda, Joseph N. , Singh, Vijay P. , Koppelman, David , Thiagarajan, Ganesh , Ramanujam, Jagannathan , Twilley, Robert
Institution: Louisiana State University - Baton Rouge , University of Louisiana at Lafayette , University of Missouri - Kansas City
Current Institution: Louisiana State University - Baton Rouge , University of Missouri - Kansas City
EPA Project Officer: Chung, Serena
Project Period: June 10, 2002 through June 9, 2004 (Extended to June 9, 2006)
Project Period Covered by this Report: June 10, 2004 through June 9, 2005
Project Amount: $129,210
RFA: EPSCoR (Experimental Program to Stimulate Competitive Research) (2001) RFA Text | Recipients Lists
Research Category: EPSCoR (The Experimental Program to Stimulate Competitive Research)
Objective:
The overall goal of this research project is to develop a coupled global climate model and hydrologic/landscape ecology model for assessing the impact of climate change on the hydrology and ecology of Louisiana wetlands. Because of the complex interaction between the climatologic, hydrologic, and ecologic processes, an integrated approach to study these processes is proposed. The proposed work involves integrating the results of a Global Climate Model with a coastal hydrodynamic model and a landscape ecology model. The model would address the issue of integrating processes occurring at widely varying spatial and temporal scales. Although the model would be applied to Louisiana wetlands, it would not be site specific and should be applicable to other regions with minimal effort. Special attention has been paid to algorithmic development so that the model would be architecturally independent. This is being achieved by developing the model code using the Fortran 90 language with the Message Passing Interface (MPI) Library, so that the model can be run on uniprocessor, multiprocessor shared memory or distributed memory systems.
A stochastic weather generation model has been developed using data archived at the National Weather Service and the Southern Regional Climate Center at Louisiana State University. The hydrologic and hydrodynamic components of the model were calibrated and verified using river stage and tide gage data collected by the United States Geological Survey (USGS), the United States Army Corps of Engineers, and the Louisiana Department of Natural Resources. The landscape ecology model will be calibrated using satellite images and aerial photographs available from USGS and National Wildlife and Fisheries.
The model will be used to study the climatological impacts on the hydrology and ecology of coastal Louisiana. The climatological scenarios include global warming caused by increased CO2 emissions and sea level rise predicted by the global climate model. The results of this study should be of interest to a broad spectrum of agencies and individual researchers who are involved in making scientific and management decisions regarding the protection, planning, and restoration of wetlands. We expect this research project to improve understanding of the coupled interactions between the climatologic, hydrologic, and ecologic factors at time scales of decades and be a first step toward the development of an effective tool for the management and restoration of ecosystems.
The specific objectives of the research project are to: (1) develop a stochastic weather generation model to obtain daily climatological data from monthly means forecasted by a Global Climate Model; (2) develop a coastal hydrodynamic and hydrologic model with subgrid scale features, such as rivers and barriers, for predicting tidal circulation in the wetlands; (3) develop a landscape ecology model to predict landscape changes as a result of changes in climatology and hydrology; (4) develop a rational methodology for coupling the various models which have diverse time and spatial scales; (5) investigate the sensitivity of the above models to initial conditions and also to changes in model parameters; (6) use the model to quantify hydrological and ecological changes as a result of changes in climate which include an increase in CO2 and an increase in sea level; and (7) improve the understanding of the coupled interactions between the climatologic, hydrologic and ecological factors at time scales of decades.
Progress Summary:
The research project consists of developing and integrating several submodels and components. A summary of accomplishments is given below:
Component 1: Stochastic Weather Generation Model
Currently a stochastic weather generation model (CLIGEN) developed by the Agricultural Research Service has been adapted to Louisiana conditions. The model was set up and is working and results have been generated. Work required to set up this model component in a stand-alone mode is completed. The Canadian Global Climate Model (CCCMA) outputs are used to drive the stochastic model.
Component 2: Coastal Hydrologic and Hydrodynamic Model
Code development and verification for correctness of the model has been completed. This model component has been parallelized to work under parallel and distributed supercomputers.
Component 3: Transport Model for Salinity, Sediments and Other Dissolved Constituents
A generic transport model component has been added and testing and verification of this model is complete.
Component 4: Parallel Linear Algebra Solvers
All the above model components require the solution of very large linear systems of equations on the order of a million unknowns. A number of parallel iterative solvers have been developed. Although significant progress was made last year additional testing revealed some inefficiencies in the solvers. These are currently being addressed.
Component 5: Landscape ecology model
Model formulation and coding currently is completed and is undergoing extensive testing. Approximately 90 percent of the work required to complete this model subcomponent has been achieved and testing of this component is nearing completion.
Component 6: Coupling of Different Sub-Models
A framework has been developed to couple these models at different spatial and temporal resolutions. The framework involves bringing the hydrodynamic and hydrologic components into sync with the time-step requirements for the ecological model. This involves averaging the hydrodynamic and stochastic model outputs on a daily basis and using these to drive the landscape ecology sub model. Changes in the landscape in terms of land/water ratios and depth are propagated back to the hydrodynamic model. Model coupling algorithms are currently being tested. Additional framework requirements in terms of efficient inter processor communication are being addressed to improve the model efficiency.
Additional Developments Currently Underway
To improve the parallel efficiency of the model a load balancing algorithm that would distribute work equally among the processor is being developed. A recursive coordinate bisection algorithm is being implemented.
Future Activities:
The activities to be performed during the next year include:
- Couple the model components so that they act in unison.
- Improve execution efficiency on parallel and distributed computing platforms.
- Perform model sensitivity to initial and boundary conditions for the landscape ecology sub-model.
- Use the model to quantify hydrological and ecological changes caused by changes in climate, which include an increase in CO2 and an increase in sea level.
- Perform a 30-year model simulation to understand the impacts of changes in climate on wetland ecosystems.
Journal Articles:
No journal articles submitted with this report: View all 4 publications for this projectSupplemental Keywords:
global climate, coastal ecosystems, ecological modeling, regional climate model, hydrodynamic model, stochastic weather model,, RFA, Scientific Discipline, Air, Geographic Area, Hydrology, climate change, State, Environmental Monitoring, Atmospheric Sciences, Ecological Risk Assessment, wetlands, fish habitat, watershed, global change, Louisiana (LA), climate models, coastal ecosystems, aquatic ecology, global warming, land and water resources, climate variability, Global Climate ChangeProgress 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.