Project Number: 3070-11130-005-000-D
Project Type: In-House Appropriated
Start Date: Mar 11, 2012
End Date: Mar 10, 2017
The long-term objective is to develop soil and water conservation decision support information for policy makers, land managers, and producers to identify conservation measures to mitigate the impacts of climate change. The Fort Cobb Reservoir(FCR)watershed, Oklahoma, was selected as the project watershed. Obj 1: Quantify the effects of past climate variations on runoff, soil erosion, sediment transport and nutrient movement for the FCR watershed, using available data records, reconstructed chronology of reservoir sedimentation, and computer modeling. 1A: Identify past climate variations and determine impacts on watershed runoff, sediment yield, and reservoir sedimentation. 1B: Reconstruct chronology of watershed sediment yield from reservoir sedimentation profiles; identify sediment sources; estimate sediment yield of major erosive storm-runoff events. 1C: Identify baseline land use, conservation, and climate conditions for impact assessment of climate change scenarios; calibrate/validate hydrologic and erosion models. Obj 2: Determine the potential impacts of 3 selected climate change scenarios on the hydrologic system and soil and water resources of the FCR watershed. 2A: Determine trends in annual precipitation and temperature for 3 greenhouse gas (GHG) emission scenarios; identify changes in seasonal precipitation and temperature distribution, estimate monthly precipitation and temperature statistics expected to prevail around the half century mark. 2B: Develop/evaluate spatio-temporal downscaling methods that integrate changed climate statistics into a synthetic weather generator; generate daily weather outcomes for each GHG emission scenario that reflect the statistical characteristics of projected climate change. Obj 3: Identify soil and water conservation strategies and options that are adapted to and mitigate the impacts of climate change, and test their effectiveness at enhancing the resilience of agricultural landscapes under climatic changes. 3A: Estimate extent of soil erosion/sedimentation under 3 GHG emission scenarios; identify soil conservation options/practices/coverage that mitigate soil erosion and sedimentation attributable to climate change; determine risk of exceeding current soil erosion and sedimentation rates. 3B: Develop communication tools that synthesize information across combinations of conservation practices, conservation coverage, climate change scenario, and conservation effectiveness. Obj 4: Develop science-based, region-specific information and technologies for agricultural and natural resource managers that enable climate-smart decision-making and where possible provide assistance to enable land managers to implement those decisions. The work will be conducted at the USDA Southern Plains Climate Change Hub and will be coordinated with NRCS, FS, and other USDA and non-USDA organizations in accordance with guidance found in the USDA Climate Change Hubs Charter and Terms of Reference.
The effects of past climate variations on runoff, soil erosion, sediment transport and fate, and nutrient movement for the Fort Cobb Reservoir (FCR) watershed are quantified based on available climate, hydrology, and environmental data records, reconstructed chronology of reservoir sedimentation, and computer modeling of watershed processes. Published climate data from Global Climate Models (GCM) are used to determine trends in annual precipitation and air temperature for three greenhouse gas (GHG) emission scenarios, identify changes in seasonal and monthly precipitation and temperature distribution within a year, and estimate monthly precipitation and temperature statistics that are expected to prevail around the half century mark. Synthetic weather generation models are used to generate daily weather outcomes that reflect the statistical characteristics of the projected climate change. Soil and water conservation strategies and options that are adapted to and mitigate the detrimental impacts of climate change are identified based on simulated soil erosion and sedimentation. Selected soil conservation options, practices, and coverage are tested with regard to their effectiveness at enhancing the resilience of agricultural landscapes under anticipated climatic changes. Risk of exceeding predefined soil erosion and sedimentation rates under climate change are determined. Information across combinations of conservation practices, conservation coverage, climate change scenario, and conservation effectiveness is synthesized and communicated in a format relevant to land managers, conservationists, and producers, as well as other practitioners. Climate smart agricultural management and decision making potential is determined based on the latest available climate information of long term historical climate records, the 5th Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), and climate projections of Global Circulation Models (GCM). Based on the insight gained, a demonstration crop production application is developed to illustrate producer's benefits and risks of including climate variations and change as an agricultural management criterion. The effects and implications of GCM climate projection lead time and uncertainties on the climate-based decision making in agricultural production and natural resources conservation is made clear.