CAREER: A Multi-Scale Approach to Assessment of Climate Change Impacts on Hydrologic and Geomorphic Response of Watershed Systems within an Uncertainty Framework

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The current ways of assessing the impacts of climate change on watershed systems are inadequate: they are based on ad hoc selection of climate models; they focus on metrics at very coarse scales detached from the reality of human activities and ecosystem services at the local (often the stream reach or floodplain) scales; and they do not yield any assessment of uncertainty associated with watershed modeling and projections into the future. This research will bridge the multi-scale, space-time connectivity of watershed systems and address uncertainty associated with their predictions through a comprehensive program of inter-disciplinary modeling and field observations and outdoor, lecture, and lab educational activities. The project will focus on the state of Michigan, where a number of observed metrics already demonstrate trends consistent with a warming climate, including shorter winters, higher mean annual temperatures, and higher frequency of heavy precipitation events. In the research component of the project, a number of case studies will be developed throughout the state along the south-southeast ? north-northwest climatic, hydrologic, and agricultural activities gradient. In addition to a synthesis of a large array of existing data sets, in situ monitoring of climatic forcing and characteristics of flow regime will be carried out to provide data for model evaluation. Multi-model ensembles of climate change projections from the World Climate Research Programme's Coupled Model Intercomparison Project will be downscaled using ?fossil-intensive?, ?mid-?, and ?lower-level? future emission scenarios of carbon dioxide (defined according to the Intergovernmental Panel on Climate Change). The inferred probabilistic information will be used to assess climate change impacts on watershed systems for early (2010?2039), mid- (2040?2069), and late century (2070?2099) periods. Specifically, changes in essential characteristics of hydrological and hydrodynamic regimes will be investigated for the case study basins using a multi-scale, physically-based framework of modeling watershed surface/subsurface processes and flow hydrodynamics, integrated through a capability of Nested Dynamics Modeling. The total uncertainty associated with biases of climate projections and inaccuracies of a watershed model will be quantified. An extensive data set of downscaled climate projections and outputs of hydrologic and hydrodynamic modeling generated in this research will provide a comprehensive volume of information required in climate change compensation and mitigation planning. The outreach component of the project will implement educational activities focusing to enhance the science class program of 7th graders in Title I schools and increase awareness of the consequences of human activities on watershed processes. The emphasis of educational activities of a week-long summer-school will be placed on underserved and underrepresented groups of students of Native American youth of Michigan, Wisconsin, and Minnesota tribes. Through the integration of research and outreach programs, the project will benefit the hydrological sciences community, middle-school, undergraduate, and graduate students.Global climate models are the tools used for exploring how earth?s climate will evolve in future under different scenarios of human activity. Outputs of these models are used in climate impact studies. The typical applications of these studies concern large-scale hydrologic variables for areas of hundreds-to-thousands of square miles; very rarely they can provide the associated uncertainty; currently, there are no studies that can address future impacts on flow hydrodynamic characteristics or floodplain inundation. Yet, most of climate change compensation and mitigation strategies require information that is relevant to scales of human activities and ecosystem services, which typically focus on watersheds, streams, agricultural fields, etc. They also require an estimate of uncertainty associated with projection into the future to make better informed decisions in conditions of climate projection inaccuracies. Responding to these societal needs, this research will use maximum available information on climate change in the form of multi-model projections and develop methodologies that will infer uncertainty of climate change predictions. In contrast to previous studies, the project will synthesize a range of hydrologic/hydrodynamic models and observational data to create capabilities for propagating information on climate signals through the entire watershed system: from headwater (source) areas to stream channels, and to the details of flow characteristics. To ensure that the issues of model applications are addressed specifically and that research findings make a practical impact, case studies will be developed throughout the state of Michigan. Furthermore, this CAREER project will integrate educational activities focusing to enhance the science class program of underserved/underrepresented student groups (low income families and Native Americans) targeting to empower their mind-sets to become future leaders and pursue science and engineering as their career choices