Rising temperatures are leading to increased demand for water and energy. In parts of the region, this will constrain development, stress natural resources, and increase competition for water among communities, agriculture, energy production, and ecological needs.

This finding is from chapter 19 of Climate Change Impacts in the United States: The Third National Climate Assessment.

Process for developing key messages: A central component of the assessment process was the Great Plains Regional Climate assessment workshop that was held in August 2011 in Denver, CO, with approximately 40 attendees. The workshop began the process leading to a foundational Technical Input Report (TIR), the Great Plains Regional Climate Assessment Technical Report.5552509e-9af3-46dd-8920-78083bee05bc The TIR consists of 18 chapters assembled by 37 authors representing a wide range of inputs including governmental agencies, non-governmental organizations, tribes, and other entities. The chapter author team engaged in multiple technical discussions via regular teleconferences. These included careful review of the foundational TIRd873710b-8d1f-43fa-bb4f-2ffe216c089c and of approximately 50 additional technical inputs provided by the public, as well as the other published literature, and professional judgment. These discussions were followed by expert deliberation of draft key messages by the authors during an in-person meeting in Kansas City in April 2012, wherein each message was defended before the entire author team prior to the key message being selected for inclusion in the report. These discussions were supported by targeted consultation with additional experts by the lead author of each message, and they were based on criteria that help define “key vulnerabilities”.

Description of evidence base: The key message and supporting text summarizes extensive evidence documented in the Technical Input Report.5552509e-9af3-46dd-8920-78083bee05bc Technical inputs (47) on a wide range of topics were also received and reviewed as part of the Federal Register Notice solicitation for public input. Temperatures are rising across the United States (Ch. 2: Our Changing Climate, Key Message 3 and its Traceable Account). Specific details for the Great Plains are provided in the Regional Climate Trends and Scenarios for the U.S. National Climate Assessment994416dc-705b-4063-b8f5-bd3ed21d4a71 with its references. Rising temperatures impact energy and water (Ch.10: Energy, Water, and Land; Ch. 4: Energy). Publications have explored the projected increase in water competition and stress for natural resources843cf523-c36c-4e7d-8824-22f65394aad9 d0828222-3fd7-4527-8d2a-895581c96ca3 d1ca2d6f-f8f7-488e-b087-22921057250c f532697a-e122-4502-8c18-9504efa60700 b9f0598c-741f-46aa-84e0-87fceb0bf1ac 78a7461f-c382-4432-9b04-3698ccb9c49e and the fragmentation of natural habitats and agricultural lands.d873710b-8d1f-43fa-bb4f-2ffe216c089c These sources provided numerous references that were drawn from to lead to this key message.

New information and remaining uncertainties: A key uncertainty is the exact rate and magnitude of the projected changes in precipitation, because high inter-annual variability may either obscure or highlight the long-term trends over the next few years. Also unknown is ecological demand for water. Water use by native and invasive species under current climate needs to be quantified so that it can be modeled under future scenarios to map out potential impact envelopes. There is also uncertainty over the projections of changes in precipitation due to difficulty of modeling projections of convective precipitation, which is the primary source of water for most of the Great Plains.

Assessment of confidence based on evidence: Very High for all aspects of the key message. The relationship between increased temperatures and higher evapotranspiration is well established. Model projections of higher temperatures are robust. Confidence is highest for the southern Great Plains, where competition among sectors, cities, and states for future supply is already readily apparent, and where population growth (demand-side) and projected increases in precipitation deficits are greatest.

References :

• Preparing for a Changing Climate: The Potential Consequences of Climate Variability and Change - Central Great Plains. Report for the U.S. Global Change Research Program (d873710b)
• Summary of Estimated Water Use in the United States in 2005. U.S. Geological Survey Fact Sheet 2009–3098 (d1ca2d6f)
• Great Plains Regional Climate Assessment Technical Report: a Report Prepared for the National Climate Assessment (5552509e)
• webpage Texas State Water Plan (78a7461f)
• Regional Climate Trends and Scenarios for the U.S. National Climate Assessment: Part 4. Climate of the U.S. Great Plains. NOAA Technical Report NESDIS 142-4 (994416dc)
• Estimated Use of Water in the United States in 2005. U.S. Geological Survey Circular 1344 (f532697a)
• Water Use for Shale-Gas Production in Texas, U.S. (b9f0598c)
• Water use for electricity in the United States: an analysis of reported and calculated water use information for 2008 (843cf523)
• The water implications of generating electricity: water use across the United States based on different electricity pathways through 2050 (d0828222)