David Brown, USDA-ARS Grazinglands Research Laboratory
Jay Lemery, University of Colorado
Xiaomao Lin, Kansas State University
Cindy Loeffler, Texas Parks and Wildlife Department
Gary McManus, Oklahoma Climatological Survey
Esther Mullens, DOI South Central Climate Adaptation Science Center
John Nielsen-Gammon, Texas A&M University
Mark Shafer, NOAA-RISA Southern Climate Impacts Planning Program
Cecilia Sorensen, University of Colorado
Sid Sperry, Oklahoma Association of Electric Cooperatives
Daniel Wildcat, Haskell Indian Nations University
Jadwiga Ziolkowska, University of Oklahoma
Ellu Nasser, Adaptation International
Katharine Hayhoe, Texas Tech University
Susan Aragon-Long, Senior Scientist
Christopher W. Avery, Senior Manager
<b>Kloesel</b>, K., B. Bartush, J. Banner, D. Brown, J. Lemory, X. Lin, G. McManus, E. Mullens, J. Nielsen-Gammon, M. Shafer, C. Sorenson, S. Sperry, D. Wildcat, and J. Ziolkowska, 2018: Southern Great Plains. In <i>Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II</i> [Reidmiller, D.R., C.W. Avery, D.R. Easterling, K.E. Kunkel, K.L.M. Lewis, T.K. Maycock, and B.C. Stewart (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, pp. 987–1035. doi: 10.7930/NCA4.2018.CH23
Quality of life in the region will be compromised as increasing population, the migration of individuals from rural to urban locations, and a changing climate redistribute demand at the intersection of food consumption, energy production, and water resources. A growing number of adaptation strategies, improved climate services, and early warning decision support systems will more effectively manage the complex regional, national, and transnational issues associated with food, energy, and water.
Food, energy, and water systems are inseparable. Any change in demand for one will impact demand on the other two. The quality of life of the 34 million people residing in the Southern Great Plains is dependent upon the resources and natural systems for the sustainable provision of food, energy, and water. At least 60% of the region’s population is clustered around urban centers, which are experiencing population growth that exceeds that of rural communities. The remaining population is spread across vast areas of rural land.14,30,31,32,33 As the population in the region grows, rapid urbanization and economic development opportunities will drive an increase in the demand for food, energy, and water. Water is used in every aspect of agricultural production and electricity generation. Energy is required to extract and deliver water of sufficient quality for diverse human and agricultural use, as well as healthy consumption and wastewater treatment. Both water and energy are required to irrigate and process agricultural products and livestock to feed the region’s increasing population. The complex interdependencies at the food–energy–water nexus create enormous challenges.
When severe drought affected the Southern Great Plains in 2011, limited water availability constrained the operation of some power plants and other energy production activities. Contention for water developed between consumers associated with the food–energy–water nexus. The recent boom in domestic unconventional oil and gas development brought on by hydraulic fracturing and horizontal drilling represents another stressor to this nexus. This development has added complexity to the regional dialog about the relationship between food, energy, and water resources.
Figure 23.5: The photo shows the drought impact on a stock pond near Kurten, Texas, in 2011. Photo credit: John …
Superimposed on the existing complexities at the intersection of food, energy, and water is the specter of climate change. During 2010–2015, the multiyear regional drought severely affected both agricultural and aquatic ecosystems. One prominent impact was a reduction of irrigation water released for the Texas Rice Belt farmers on the Texas coastal plains, as well as a reduction in the amount of water available to meet instream flow needs in the Colorado River and freshwater inflow needs to Matagorda Bay. The Lower Colorado River Authority (LCRA), through its Water Management Plan (WMP), balances the needs of competing water demands in the Lower Colorado River Basin of Texas. Depending upon the amount of water stored in lakes, the WMP requires that LCRA reduce or cut off interruptible stored water for most downstream agriculture so firm water supplies are available to meet the basic needs of cities, businesses, and industries during drought.
In one year, planted acres of rice in Matagorda County, Texas, dropped from 22,000 acres to 2,100 acres.34 The ripple effect on the local economy was severe, with a 70% decline in sales of farm implements and machinery. Some family-owned establishments that had survived for decades closed permanently.35 Irrigation strategies shifted from river-based to pumping water from the Gulf Coast Aquifer, and dozens of new wells were drilled. Drilling water wells then resulted in declining groundwater levels, adding stress to water levels that had historically been falling in the region.36 Some farmers attempted to adapt by making the difficult transition to other crops such as corn. However, when flooding rains inundated the region in 2016, 15% of the corn crop was swept away in flood waters.37 Thus the 2010–2015 drought simultaneously affected agriculture, energy, recreation, and economic activity, eventually leading to increased groundwater development and potential future overexploitation. Projected increases in drought duration and severity imply even more pervasive direct and indirect effects. These impacts might have been even more severe had it not been for adaptation actions taken by the City of Austin, including implementation of drought contingency plans and water-use cutbacks in coordination with the City Council and community.
Climate change has significant negative impacts on agriculture in the United States, causing substantial economic costs (Ch. 10: Ag & Rural).38,39 The effects of drought and other occurrences of extreme weather outside the Southern Great Plains also affect the food–energy–water nexus in the region. The neighboring Southwest region is especially vulnerable to climate change due to its rapidly increasing population, changing land use and land cover, limited water supplies, and long-term drought (Ch. 25: Southwest).40 States in the Southern Great Plains import over 20% of their food-related items from Arizona, and El Paso, Texas, receives 25% of its consumable foods (mostly vegetables) and 18% of its animal feed supplies from Arizona.41 In addition, relationships across the border of the Southern Great Plains with Mexico will be critical to a better understanding of the food–energy–water nexus (see Case Study “Rio Grande Valley and Transboundary Issues”) (see also Ch. 16: International, KM 4).
The 2017 Texas State Water Plan52 indicates that the growing Texas population will result in a 17% increase in water demand in the state over the next 50 years. This increase is projected to be primarily associated with municipal use, manufacturing, and power generation, owing to the projections of population increase in the region. Likewise, the Oklahoma Water Plan indicates that water use projections in Oklahoma are expected to increase by 21% for municipal use, 22% for agricultural use, and 63% for energy use.53 The Kansas Water Plan’s preliminary assessment of projected water demand in Kansas also shows an increase of 20%, but with the expected variability depending upon rural versus urban areas.54 Throughout much of western Kansas, western Oklahoma, and the Texas Panhandle, groundwater from the Ogallala Aquifer is the dominant water source,17,55 benefitting the agricultural sector in particular. This resource is known to be shrinking faster than it is replenishing, and some portions are likely to become an insufficient source or become completely depleted within the next 25 years, particularly at its southernmost extent.17 Drought more persistent than that experienced in the region’s recent history would trigger large social and economic consequences, including shifting agriculture, migration, rising commodity prices, and rising utility costs.20
The importance of groundwater as a resource will increase under a changing climate as the intensification of hydrologic extremes decreases the reliability of precipitation, soil moisture, and surface water, and as surface water supplies are becoming increasingly over-allocated.56,57,58
Research into the food–energy–water nexus is in its early stages and historically tends to examine only one or two components.59,60,61,62,63,64,65 It is clear that tradeoffs and cascading complexities exist between sectors, and changes in one sector are likely to propagate through the entire system (Ch. 17: Complex Systems). There are significant gaps in the scientific understanding regarding the role that climate change will play as a disruptive force and a threat to food, energy, and water security.60,63,66,67,68