Abstract Ebullitive methane (CH 4 ) emissions in lentic ecosystems tend to concentrate at river‐lake interfaces and within shallow littoral zones. However, inconsistent definitions of the zone static representations lake or reservoir surface area contribute major uncertainties greenhouse gas (GHG) estimates, particularly reservoirs with large water‐level fluctuations. This study examines temporal variation total areas US demonstrates how different methods data sources lead discrepencies GHG...

This study demonstrates a number of methods for using field sampling and observed lake characteristics patterns to improve techniques development algae remote sensing models applications. As satellite airborne sensors their data are more readily available, applications estimate water quality via becoming practical local monitoring, particularly surface algal conditions. Despite the increasing applications, there significant concerns associated with model application, several which addressed...

Abstract Streamflow monitoring in the Colorado River Basin (CRB) is essential to ensure diverse needs are met, especially during periods of drought or low flow. Existing stream gage networks, however, provide a limited record past and current streamflow. Modeled streamflow products with more complete spatial temporal coverage (including National Water Model [NWM]), have primarily focused on flooding, rather than sustained flow conditions. Objectives this study (1) evaluate historical...

In the transition to low-carbon electricity, well-quantified estimates of carbon dynamics are needed ensure that emissions reduction targets achieved. We review state science on accounting for hydropower reservoirs and identify limitations future solutions. Nearly all research reservoir greenhouse-gas (GHG) has focused individual in isolation without considering their position a freshwater network draining organic matter from upstream watersheds or coordinated operation cascades. Second,...

Reservoir sedimentation poses significant challenges for water storage, including drinking supply, irrigation, recreations, flood control, and other uses. However, accurate quantification of present future reservoir remains a considerable challenge. One the main obstacles is lack repeated capacity surveys that cover same spatial domains employ consistent pre- post-processing methods. Additionally, incorporating intricate nonlinear morphodynamics into nontrivial. In this study, we analyze...

Abstract Reconstructed historical streamflow time series can supplement limited gauge observations. However, there are common challenges of typical modeling approaches: process‐based hydrologic models be data/computation‐intensive, and statistics‐based region/stream‐specific. Here we present a nationally scalable framework integrating the simulated runoff from Variable Infiltration Capacity (VIC) model with Routing Application for Parallel computatIon Discharge (RAPID) routing leveraging...

Hydropower plays a key role in the evolving energy grid. In United States, thousands of non-powered dams (NPDs) represent untapped opportunities for new production. This paper reviews past NPD resource assessments, with particular focus on those and evaluates where there is room improving methods, data, assumptions estimating development potential. Through this review, we catalog types information that are available to stakeholders involved development. Past assessments have generally...

Remote sensing models estimate chlorophyll concentrations by correlating spectral reflectance and reservoir chlorophyll. Different algal populations have different signatures thus correlation models, an issue typically addressed developing applying a model using the same satellite image. Here we exploit these population differences seasonal that can be applied to other images from season. We rely on succession assume phytoplankton is relatively constant over season, dividing growth season...

Spectral images from remote sensing platforms are extensively used to estimate chlorophyll-a (chl-a) concentrations for water quality studies. Empirical models estimation often based on physical principles related light absorption and emission properties of chl-a generally relying spectral bands in the green, blue, near-infrared bands. Because characteristics, constituents, algae populations vary widely lake lake, it can be difficult coefficients these models. Many studies select a model...

Hansen CH, Burian SJ, Dennison PE, Williams GP. 2019. Evaluating historical trends and influences of meteoorological seasonal climate conditions on lake chlorophyll a using remote sensing. Lake Reserv Manage. 36:45–63.Evaluations long-term water quality patterns in lakes reservoirs are often inhibited by irregular records. This study uses Landsat satellite imagery to construct more complete record algal biomass (measured via [Chl-a]) presents framework for developing estimation models open...

Remote sensing techniques are proven methods for quantifying chlorophyll-a levels by inference algal concentrations in reservoirs. One traditional method is to use Landsat imagery and field data from a limited time period develop model reservoir which relates reflectance various bands measured (or chlorophyll-a) that associated determine spatial the reservoir. In this work, we extend these historical over long periods seasonal models will more accurately describe conditions throughout...

Future precipitation projections—and subsequent variation in simulated runoff response—can have a large impact on the planning and design of hydraulic structures water systems are, therefore, an important input hydrologic modeling. These projections are often derived from coarse-scaled climate models may require downscaling bias-correction techniques to be suitable for local-scaled applications. Here, one simple commonly used approach, called change factor methodology (CFM), is modified...

Algae blooms pose a threat to water quality by depleting oxygen during decomposition and also cause other issues with use. biomass is traditional monitored through field samples analyzed for chlorophyll-a, pigment present in all algae. Field sampling can be time- cost-intensive, especially areas that are difficult access provides only limited spatial coverage. Estimations of algal based on remote sensing data have been explored over the past two decades as supplement information obtained...

Abstract Reservoirs are a significant source of carbon (C) to the atmosphere, but their emission rates vary in space and time. We compared C emissions via diffusive ebullitive pathways at several stations six large hydropower reservoirs southeastern US that were previously sampled summer 2012. found dioxide (CO 2 ) diffusion was dominant flux pathway during 2012 2022, with only three exceptions where methane (CH 4 or CH ebullition dominated. positively associated water temperature. However,...

Jiada Li1*, Carly Hansen2, Steven Burian31Department of Civil and Environmental Engineering, Colorado State University, Fort Collins, CO, USA2 Sciences Division, Oak Ridge National Laboratory, Ridge, TN, USA3Department Civil, Construction, University Alabama, Tuscaloosa, AL USA

Greenhouse gas (GHG) emissions from reservoirs are influenced by many factors, including the reservoir's morphology, watershed, and local climate. Failure to account for diversity in waterbody characteristics contributes uncertainties estimates of total GHG limits ability extrapolate patterns one set another. Hydropower particular interest given recent studies that show variable - sometimes very high measurements emissions. This study uses describing reservoir surface morphology location...

Because methane is a potent greenhouse gas (GHG), understanding controls on emissions from reservoirs an important goal. Yet, are complex ecosystems, and mechanisms by which reservoir operations influence poorly understood. In part, this because occur in ‘hot spots’ moments’. study, we address three research questions, ‘What the causal pathways through resulting water level fluctuations (WLF) emissions?’; ‘How do influences WLF differ for seasonal drawdown diurnal hydropeaking operations?’;...

Abstract Long‐term planning and operation of hydropower reservoirs require an understanding both water energy storage. As storage needs the evolving grid increase, we must account for potential these reservoirs. Given limitations current data on existing hydropower, compile statistics related to volume hydraulic head from publicly available sets examine differences in descriptions US Assembled characteristics are used calculate nominal capacity, a simple measure generate power given water,...

As is the case with many large lakes, field sampling records (and understanding of historical water quality) in Great Salt Lake natural surface system are heavily limited due to time and cost constraints, as well a number independent organizations collecting managing data.To address these deficiencies, remote sensing quality used hind-cast conditions algal blooms GSL (GSLSWS).This unique because its lakes closely connected, yet have widely varying characteristics conditions.An approach for...