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Filters: Tags: Water Resources (X) > Categories: Project (X) > partyWithName: John Wesley Powell Center for Earth System Analysis and Synthesis (X)

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There has been increasing attention placed on the need for water availability information at ungauged locations, particularly related to balancing human and ecological needs for water. Critical to assessing water availability is the necessity for daily streamflow time series; however, most of the rivers in the United States are ungauged. This proposal leverages over $1M currently allocated to the USGS National Water Census Program towards developing an integrated modeling approach to estimate daily streamflow at ungauged locations, with the ultimate goal of providing daily streamflow estimates at 160,000 ungauged catchments across the United States. By assembling a diverse and prolific group of international scientists,...
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Shale gas is a key source of onshore domestic energy for the United States and production of this resource is increasing rapidly. Development and extraction of shale gas requires hydraulic fracturing, which entails horizontal drilling, perforation of steel casing and cement grout using explosive charges, and expansion of fractures using fluids under high pressure. Concern over potential environmental effects of shale gas development is growing and based on a recent review there is very little information in the scientific literature on potential environmental effects of hydraulic fracturing. We propose to conduct the first broad scale, data-based assessment of the potential effects of hydraulic fracturing on water...
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Global hydroclimatic conditions have been significantly altered, over the past century, by anthropogenic influences that arise from warming global climate and also from local/regional anthropogenic disturbances. There has been never been an effort that has systematically analyzed how the spatio-temporal variability of land-surface fluxes vary in natural and human-altered watersheds globally. This synthesis study will adapt and extend the classical Budyko framework to quantify the role of drivers - changing climate and local human disturbances - in altering flow regimes and in creating urban heat island episodes over the globe. An allied goal is to develop parsimonious hydroclimatic models that explain the spatio-temporal...
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Models that predict the flow of rivers and streams are critically important for planning flood control, hydropower, and reservoir operations, as well as for management of fish and wildlife populations. As temperatures and precipitation regimes change globally, the need to improve and develop these models for a wider spatial coverage and higher spatial fidelity becomes more imperative. Currently, one of the biggest impediments to developing robust streamflow knowledge is incomplete understanding of the range of timescales over which water is stored (e.g., in snowpack, soils, and groundwater) in watersheds, as well as the processes and factors that control those storage timescales. This working group will address...
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Geographically Isolated Wetlands (GIWs) occur along gradients of hydrologic and ecological connectivity and isolation, even within wetland types (e.g., forested, emergent marshes) and functional classes (e.g., ephemeral systems, permanent systems, etc.). Within a given watershed, the relative positions of wetlands and open-waters along these gradients influence the type and magnitude of their chemical, physical, and biological effects on downgradient waters. In addition, the ways in which GIWs connect to the broader hydrological landscape, and the effects of such connectivity on downgradient waters, depends largely upon climate, geology, and relief, the heterogeneity of which expands with increasing scale. Developing...
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River ecosystems support a wide diversity of biota, including thousands of fish species, which are variously adapted to the dynamic environments provided by flowing-water habitats. One of the primary ways that human activities diminish the biological capacity of rivers is by altering the natural hydrologic variability of river systems through regulation and diversion of streamflow for other uses. Managers may be able to avoid some of the worst effects of flow management on aquatic biota if we understand the mechanisms by which streamflow components, such as unusually high and low flow events, affect populations (e.g., by influencing recruitment and mortality). Numerous past studies have described correlative associations...
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Water cycling and availability exert dominant control over ecological processes and the sustainability of ecosystem services in water - limited ecosystems. Consequently, dryland ecosystems have the potential to be dramatically impacted by hydrologic alterations emerging from global change, notably increasing temperature and altered precipitation patterns. In addition, the possibility of directly manipulating global solar radiation by augmenting stratospheric SO2 is receiving increasing attention as CO2 emissions continue to increase - these manipulations are anticipated to decrease precipitation, a change that may be as influential as temperature increases in dryland ecosystems. We propose to integrate a proven...
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Groundwater withdrawals in the western US are a critical component of the water resources strategy for the region. Climate change already may be substantially altering recharge into groundwater systems; however, the quantity and direction (increase or decrease) of changes are relatively unknown as most climate change assessments have focused on surface water systems. We propose to conduct a broad scale literature review followed by a synthesis of available data, analysis and simulations with available downscaled climate scenarios to understand how recharge in the western US might respond to plausible climatic shifts during the rest of the 21st Century. We will produce an estimated range of impacts on groundwater...
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Everyone needs clean drinking water in order to thrive. The US EPA and public water purveyors in the US work together in adherence with the Safe Drinking Water Act to make water safe for public consumption. The recent media coverage of lead in public drinking water supplies in Flint, Michigan, and schools in many cities with aging infrastructure throughout the US has raised public awareness of drinking water as a potential pathway of exposure to toxic chemicals. Epidemiologists and other researchers have conclusively shown that high arsenic levels in drinking water in Bangladesh, Taiwan, and South America cause adverse human health outcomes. However, research in study populations with levels of arsenic exposure...
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Groundwater storage depletion is a critical issue for many of the major aquifers in the U.S., particularly during intense droughts. The GRACE (Gravity Recovery and Climate Experiment) satellites launched in 2002, with sensors designed to measure changes in the Earth’s gravitational field at large spatial scales (≥ ~200,000 km2). These changes are primarily driven by changes in water storage on the Earth’s surface. Estimates of groundwater storage changes based on these gravity measurements have attracted considerable media attention in the U.S. and globally. However, groundwater storage changes are computed indirectly by subtracting snow, surface water, and soil moisture storage from the total water storage monitored...
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Resilience science provides a conceptual framework and methodology for quantitatively assessing the ability of a system to remain in a particular state. Probable non-linear ecological responses to global change, including climate change, require a clear framework for understanding and managing resilience. However, much of the resilience research to date has been qualitative in nature, and frameworks developed for the implementation of resilience science have been either vague or focused on the social component of social-ecological systems. Attempts to quantify resilience and operationalize the concept include the cross-scale resilience model, discontinuity theory and the early detection of leading indicators of...
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The transport of dissolved organic matter (DOM) by rivers is an important component of the global carbon cycle, affects ecosystems and water quality, and reflects biogeochemical and hydrological processes in watersheds. Understanding the fundamental relationships between discharge and DOM concentration and composition reveals important information about watershed flow paths, soil flushing, connectivity to riparian zones, organic matter leaching, soil moisture, and climatic influences. Data to describe these processes - both magnitude and timing - is critical for modeling and predicting watershed DOM dynamics, particularly in light of land use and climate change . Despite several decades of data collection, a synthesis...
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One of the grand challenges of Earth Surface Science and Natural Resource Management lies in the prediction of mass and energy transfer for large watersheds and landscapes. High resolution topography (lidar) datasets show potential to significantly advance our understanding of hydrologic and geomorphic processes controlling mass and energy transfer because they represent features at the appropriate fine scale on which surface processes operate. While lidar datasets have become readily available across the United States, challenges remain in extracting accurate and objective information relevant for hydrologic and geomorphic research, modeling, and prediction, as well as watershed management. We primarily focus our...
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Climate change is expected to cause more intense and frequent extreme weather events, but we only have a basic understanding of how these events might alter freshwater systems. Storms are likely to impact lake systems through delivery of sediments from watersheds and mixing of the water column, both of which could have important consequences for phytoplankton. Phytoplankton are the base of the food web; their community configuration and how the community changes across seasons have large impacts on ecosystem processes such as energy flow, nutrient cycling, and carbon cycling. External disturbances may abruptly alter phytoplankton community dynamics and thus impact ecosystem function. The effects of storms on the...
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Dam decommissioning is rapidly emerging as an important river restoration strategy in the U.S., with several major removals recently completed or in progress. But few studies have evaluated the far-reaching consequences of these significant environmental perturbations, especially those resulting from removals of large (>10-15 m tall) structures during the last decade. In particular, interactions between physical and ecological aspects of dam removal are poorly known. From recent work, however, observations are now available from several diverse settings nationwide to allow synthesis of key physical and ecological processes associated with dam removals, including fish and benthic community response, reservoir erosion,...
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Drylands are integral to the Earth system and the present and future of human society. Drylands encompass more than 40% of the terrestrial landmass and support 34% of the world’s human population. Biocrusts are the “living skin” of Earth’s drylands, sometimes dominating the ground cover and figuring prominently in ecosystem structure and function. Biocrusts are a biological aggregate of cyanobacteria, fungi, algae, lichens and mosses in the surface millimeters of soil. By aggregating soil, biocrusts make sediment less erodible. They also strongly influence the water runoff-infiltration balance. In some ecosystems they generate runoff, whereas in other systems they enhance water capture. Vascular plant germination,...
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Groundwater contaminated with naturally occurring arsenic is a widespread problem affecting many alluvial and deltaic aquifer systems throughout the world. The human health toll from consuming groundwater with high levels of arsenic is staggering in its proportions. Furthermore, the use of arsenic contaminated groundwater for irrigation is observed to result in diminished crop yields and thus poses a threat to food security in arsenic affected regions. Decades of research at individual field sites have resulted in the collection of many geochemical and geologic datasets. A key feature of alluvial and deltaic aquifer systems is the large degree of spatial variability in groundwater arsenic concentrations from local...
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Fluid injection induced seismicity has been reported since the 1960s. There are currently more than 150,000 injection wells associated with oil and gas production in 34 states in the conterminous US. Pore pressure disturbance caused by injection is generally considered the culprit for injection induced seismicity, but, not all injection causes seismicity. It is not well understood what mechanical and hydrologic conditions cause some sites to be more prone than others to seismicity. The objectives of this proposed research are to utilize existing data on fluid injection and seismicity to (1) identify spatial and temporal correlations between fluid injection and induced seismicity; (2) conduct a hydro-mechanical modeling...
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Streams and rivers have a limited spatial extent, but are increasingly recognized as key components of regional biogeochemical cycles. The collective metabolic processing of organisms, known as ecosystem metabolism, is centrally important to nutrient cycling and carbon fluxes in these environments, but is poorly integrated into emerging biogeochemical concepts. This line of inquiry lags behind other aspects of regional biogeochemistry because of the lack of long-term, regionally-diverse studies of stream metabolism. With a few exceptions, metabolism studies have focused on small headwater catchments using short-term (days to weeks) observation. As a consequence, basic patterns and controls of this fundamental process,...
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Rivers are the veins of the landscape, providing environmental benefits that are disproportionately high relative to their aerial extent; shedding flood waters, hosting aquatic ecosystems, transporting solutes and energy-rich materials, and storing and transforming pollutants into less harmful forms. From uplands to the coasts, rivers facilitate key biogeochemical reactions that cumulatively influence water quality. Many of the reactions are optimized outside the main channel, in hyporheic zones, riparian zones, and floodplain areas, where riverine water is in close contact with geochemically and microbially-active sediments. However, little is known about the distribution, intermittency, and overall effectiveness...