New technologies in agriculture, crop genetics, and livestock production, and expanded use of surface and groundwater through irrigation have facilitated the expansion and diversification of Great Plains agriculture. The water resources of the region are being challenged by increasing competition among long-dependent agricultural users, the needs of the natural ecosystems, and the ever-expanding numbers of urban and industrial users. Along with the stress from a changing climate, the face of rural economies and agriculture is changing globally with changing consumer tastes, consolidation of various industries, and world export trade. Great Plains' farmers and ranchers have excelled by being adaptive and by incorporating new technologies to buffer their production against the region's highly variable climate. That success has been so impressive it is a tribute to human ingenuity.

Changes in climate are also likely to pose challenges to the region's water quality and supply, and to the rural economies of the Great Plains, adding to stresses already existing. Warmer temperatures, increases in evaporation, changes in precipitation patterns, and possible increases in the severity and frequency of extreme weather events could combine to alter the way water management currently sustains Great Plains agriculture. In addition, climate change could alter the current distribution and mix of plants and animals found on the Great Plains, resulting in different plant and animal species. A possible migration of invasive species across the Great Plains is a concern to stakeholders in the region because of the challenges to agriculture and natural ecosystems.

Rural communities, already stressed by their declining populations and shrinking economic bases, are dependent on the competitive advantage of their agricultural products in domestic and foreign markets. A changing climate will likely bring additional stresses that will disproportionately affect family farmers and ranchers.

Although the potential impacts of climate change explored in this paper are based on results from climate models that are imperfect at projecting climate change at the regional level, the scenarios that have been developed nevertheless represent plausible futures. As such, they warrant our serious attention and can provide the basis for considering strategies that could be used to reduce, and in some cases prevent, the potential adverse impacts from coming true.