Managing environmental change requires the ability to predict water cycle response at a range of scales. Increasingly predictions must include implications of human behavior, understanding legacy effects of past behavior, and emergent behavior of human-impacted hydrologic systems. This session welcomes contributions covering important open questions focused on predicting the dynamics of water resources and aquatic ecosystems under highly uncertain conditions. This includes nonlinear coupling and feedbacks, coupled hydrological, biogeochemical, ecological and geomorphological processes, threshold behavior and scaling phenomena, and how human-induced climate and land use and land cover change impacts these processes.
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Changes in storage moderate the fluxes and control a wide range of hydrologic and biologic functions of a catchment. However, quantifying the amount of water present in a watershed is seldom done. Storage and its partitioning between groundwater, soil moisture, snowpack, vegetation, and surface water are the variables that ultimately characterize the state of the hydrologic system. It is essential to understand how a catchment retains water as well as how it releases water. We welcome submissions illustrating field methods to quantify storage dynamics across scales, modeling studies incorporating storage dynamics as a key modeling target, and studies documenting the relationships between catchment storage and hydrologic functions.
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Subsurface systems, with limited characterization and inadequate conceptual models, are plagued by uncertainty. Inverse parameter estimates are only as precise as permitted by measurement errors, model assumptions and available data. Here, we are interested in techniques for quantifying uncertainty in parameter estimation, impact of that uncertainty on follow-on predictive models and any subsequent impact on our capacity for risk assessment and decision making. Any comprehensive risk assessment should address the following questions: What can happen? What is the probability it occurs? And what are the consequences? We welcome presentations on parameter estimation, quantification of associated uncertainty, approaches to propagate uncertainty in posterior predictive models, risk analysis and decision making under uncertainty.
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More than 800,000 dams exist worldwide with approximately 75,000 in the U.S. alone. By design, dams alter river flows and consequently change the natural flow of sediment, nutrients, and organic debris. Dams fragment aquatic environments and often result in loss or impairment of valuable ecosystems and species extinctions. Dam removal serves as a natural experiment to observe the recovery of natural stream processes and associated biota over time and space. While more than 58 large and small dams were slated for removal in 2009, very little research into the effects is being done. This session will present the results of dam removal research and monitoring with a focus on the quantification of fluvial and biological impacts.
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New approaches to hydrologic modeling, data representation and analysis offer the opportunity to advance hydrologic understanding through integrated holistic representations of water processes in catchments and the critical (earth) zone. Data organization can enhance or inhibit its analysis and affects collaboration on local, national and international issues. This session invites contributions on any and all aspects of using advanced computing and information technology in hydrology, including computer intensive frameworks for data sharing and new approaches for achieving model interoperability scaled from the desktop to the cloud and involving both research and operational hydrologic models and water data systems.
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Uncertainty-quantified water resources and flood forecast products help support risk-based decision making in a wide range of applications. This session seeks contributions from the research, operational, and user communities on recent advances in science and applications of hydrologic ensemble forecasting systems, including: (1) modeling and propagation of uncertainty in hydrologic forecast systems on multiple space-time scales, (2) improving uncertainty modeling and forecasts of extreme events, (3) ensemble verification methods and case studies, (4) communication of uncertainty-quantified forecast products, (5) end-user applications of hydrologic ensemble forecasts, including risk-based decision support systems.
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DOM is an important vector for contaminants and has important implications for ecosystem processes and water quality. Thus, understanding the production, transport, cycling and consumption of DOM in terrestrial and aquatic ecosystems is critical. Here we solicit contributions on DOM that address: tracing sources of DOM in watersheds and the role of hydrologic flow paths in the transport of DOM; the influence of terrestrial and aquatic ecosystem processes on DOM; use of spectrofluorometric methods to characterize DOM quality and their use as proxies for degradability, mobility and bioavailability of DOM; and the evolution of DOM across spatial and temporal scales in forest and human-dominated watersheds.
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Mountainous ecosystems are considered early indicators of climate change, given that subtle changes in the energy balance may result in drastic changes in hydrologic regimes, vegetation dynamics, and ecosystem biogeochemical fluxes. Fine-scale heterogeneity of complex topography leads to steep physical gradients over short distances and offers unique challenges and opportunities to understand water-controlled processes. This session addresses the interactions and feedbacks among water, nutrients, and climate, from various perspectives including hydrology, biology, and soil and atmospheric sciences, in high-elevation ecosystems and areas of complex topography. This session is accompanied by the overview Union session, U12.
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Recent advances in sensor technology have significantly enhanced our ability to collect high resolution (e.g. continuous) water quality data in freshwater ecosystems. Measurements that capture spatial and temporal variability allow us to assess how, for example, precipitation variability and disturbance frequencies alter the timing and magnitude of constituent fluxes from watersheds. We solicit presentations that use continuous measurements to better understand fundamental biogeochemical and hydrological processes in freshwater ecosystems, as well as applied studies related to water quality and watershed management. Studies on the application of optical sensors for organic matter and nutrients are especially encouraged.
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Ontologies have increasingly become a more common sight in a number of earth science informatics applications. They have been utilized for different purposes, for example to mediate between semantic heterogeneities or knowledge representations that can either be reasoned from or queried against. This session aims at bringing together researchers that have made use of ontologies in a variety of scenarios and how ontologies have been embedded in larger systems in which they fulfill a specific purpose. The session is not limited to applications only but also invites contributions that deal with ontology visualization, ontology growth and maturation based on community input and development, and also how ontologies can be interacted with.
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Mountainous ecosystems are considered early indicators of climate change, given that subtle changes in the energy balance may result in drastic changes in hydrologic regimes, vegetation dynamics, and ecosystem biogeochemical fluxes. Fine-scale heterogeneity of complex topography leads to steep physical gradients over short distances and offers unique challenges and opportunities to understand water-controlled processes. This session addresses the interactions and feedbacks among water, nutrients, and climate, from various perspectives including hydrology, biology, and soil and atmospheric sciences, in high-elevation ecosystems and areas of complex topography. Please submit contributed submissions to session B47.)
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