USGCRP Home National Assessment Acclimations November-December 1999 Southeast Regional Assessment Status | | Search |
Southeast
Regional Assessment Status |
By Ronald L. Ritschard, University of Alabama
Using input from the June 1997 Southeast Regional Scoping workshop and follow-on meetings with other regional stakeholders, an interdisciplinary research team was organized to conduct a Regional Assessment of the implications of climate variability and change on agriculture, forests, environmental quality (air and water), and the cross-cutting implications of water resources on these sectors. The assessment team includes researchers from Auburn University, Florida State University, North Carolina State University, Research Triangle Institute, University of Alabama (in Tuscaloosa and Huntsville), University of Florida, US Forest Service, and USDAs Peanut Research Laboratory. The team also works closely with the Southern Growth Policies Board, Appalachian Regional Commission, state and local government agencies (i.e., Alabama Department of Economic Affairs), utility companies, and with the agricultural extension in several southeastern states. It is anticipated that these stakeholder relationships will be enhanced in the future as assessment results and new analytical methods and data become available. A brief summary of our progress to date is provided below. Agriculture Crop yield simulations with the Hadley (HadCM2) climate scenarios for the decades around 2030 and 2090 were performed using current management conditions for six key crops (corn, peanut, rice, soybean, sorghum, and winter wheat). County-level yield results and irrigation demand by crop were estimated for the entire southeastern US. As shown in Figure 1, there is considerable variability among crops with regard to their sensitivity to climate variations. Corn and sorghum, for example are particularly sensitive to higher temperatures. These maps also show the spatial variability in crop response across the Southeast. Preliminary results indicate that most negative effects are found in the Gulf Coast region. These crop responses will also be used in a USDA/ARS regional farm management model (PNTPLAN) to determine how farm managers might respond. Farm management optimization is being run for these crops using the climate-induced yield changes for 2030 and 2090 assuming a representative 200-acre farm with current crop mix and crop yield for each county. A full set of results for all locations and all six crops is expected by the end of 1999. |
Figure 1a
- Projected chages in 30-year averaged rainfed yields of crops in
the Southeast by 2030 using VEMAP Hadley climate scenario.
Figure 1b
- Projected chages in 30-year averaged rainfed yields of crops in
the Southeast by 2090 using VEMAP Hadley climate scenario
Forestry As part of the regional assessment, the Hadley (HadCM2) climate scenarios were also applied to a forest productivity model (PnET-II) across the southeastern states. This forest process model combines climate, soil, and vegetation data to predict productivity, soil water stress, and drainage. Figure 2 shows results for pine and southern hardwoods comparing baseline conditions (2000) to 2090. Under baseline conditions southern pine productivity would be approximately 5% less than hardwood productivity, but by 2090 hardwoods would be about 27% more productive than pine forests across the southeast region. Pines have greater water demands than do hardwoods on an annual basis. Even with the increased water use efficiencies associated with increased atmospheric CO2, the southern pines are limited by water as evapotranspiration rates increase with air temperatures. These responses, however, could likely be ameliorated since pine plantation managers would be able to adapt silvicultural techniques and species composition in response to climate change. The forest productivity results are being linked to the Sub-Regional Timber Supply model. This economic model uses relationships between prices, harvest, and inventory to suggest the market effects of shifts in supply or demand. We expect these economic results will become available over the next few months. |
Figure 2 - Forest productivity model (PnET-II) results for pine and southern hardwoods.
Water Quality Integration The most innovative feature of this assessment is the application of an integrated approach that links climate variability and change with crop yields, regional economics, and forest productivity and timber markets. The results of these linkages will then be used in a land use model to estimate economic incentives for land use conversions between agricultural and forest lands. Over the next few months, the Southeast Regional Assessment team plans to complete these analyses and document the results in a summary regional report. The next step in the overall assessment process will be to transfer this new understanding to relevant stakeholders in the region through education, data interpretation, and introduction of simplified analytical tools and other products that can be incorporated into existing decision-making processes at the local and regional levels. Meetings are already being planned with several state and local government agencies and with representatives from the agricultural sector (i.e. agricultural extension, farm cooperators, agribusiness) to identify specific assessment products that can be applied to local, state, and regional problems. For more information, contact: Ronald L Ritschard, Earth System Science Laboratory, Global Hydrology and Climate Center, University of Alabama; 977 Explorer Blvd., Huntsville, AL 35806; phone: (256) 922-5801; email: ron.ritschard@atmos.uah.edu |
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