CNH: Climate Change, Hydrology, and Landscapes of America's Heartland: A Multi-Scale Natural-Human System

A lynchpin between nature and society, agricultural landscapes are finely adapted to socioeconomic forces and climate, yet both are now in flux. This interdisciplinary research project will investigate the effects of anticipated climatic change on the agricultural heartland of the central United States and how adaptations to climate change will generate new landscape patterns. As a coupled natural-human system with climatic, agrotechnology, market, and policy feedbacks, future landscapes will differ from current patterns in terms of water quantity, water quality, and agricultural production. The investigators will focus their attention on three central sets of research questions: (1) How will 21st-century climate change, together with changing market and policy environments, affect land-use patterns at various scales ranging from the central U.S. as a whole to macroscale regions like the "Corn Belt" to mesoscale watersheds to individual farms and fields? How will this change the geography of agricultural production? (2) Under what policies and prices does landscape change induced by climate change generate a positive or a negative feedback through changes in carbon storage, evapotranspiration, and albedo in agricultural landscapes? (3) Will climate change expand or diminish the agricultural production and ecosystem service generation capacities of mesoscale watersheds representative of agricultural regions? These questions will be answered using linked methodologies, starting with downscaling of greenhouse gas emissions scenarios based on the 5th Assessment Report of the IPCC for 2020-2025, 2030-2035, 2060-2065, and 2095-2100 that will drive agent-based models of farmer behavior. From these scenarios, land-use change models utilizing the NASS/USDA Cropland Data Layer will generate most-likely landscapes for the American agricultural heartland. The SWAT watershed model then will be used to derive estimates of stream flow, sediment, and nutrient loads, which will be used in conjunction with carbon storage estimates from EPIC in a genetic algorithm to derive ecological-economic production possibility frontiers for each representative watershed for each time period for each climatic scenario. The investigators hypothesize that climatic change will diminish agricultural and ecologic potentials in some regions, such as through reduced water availability, while it will expand in other areas, such as through lengthening of the growing season, but these effects will be greatly influenced through market and policy developments, such as biofuel production and carbon credits.

This project will enhance basic understanding about the ways that climate change will affect agricultural land use and water resources under various policies and incentive structures. Project results will facilitate early adaptation and make a timely contribution to the successful integration of agricultural, environmental, and trade policy. Maps that will show where cropping patterns and associated agricultural revenues, water quantity, and water quality are most likely to change will be disseminated to the broad scientific community and relevant policy makers in USDA and other relevant governmental bodies. Middle and high school teachers will be directly involved in developing teaching modules, distributable by CD/ROM and consistent with existing educational policies and practices, to bring building block concepts in systems and modeling approaches to nature-society interaction to Grade 6-12 science and Grade 9-12 social studies education. This project is supported by the NSF Dynamics of Coupled Natural and Human Systems (CNH) Program.