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These data were compiled for a joint mark-recapture analysis of humpback chub and rainbow trout and include capture histories for both species, as well as environmental covariates associated with monthly time steps used to measure survival and growth and environmental covariates used to predict capture probability during each sampling trip. This worksheet also include parameter estimates and associated variance-covariance matrix from a prior analysis, which were combined with the output from the joint mark-recap analysis to predict equilibrium adult abundances under a variety of scenarios.
Natural gas plays a key role in our nation’s clean energy future. Recent advances in drilling technologies—including horizontal drilling and hydraulic fracturing—have made vast reserves of natural gas economically recoverable in the US. Responsible development of America’s oil and gas resources offers important economic, energy security, and environmental benefits. Hydraulic fracturing is a well stimulation technique used to maximize production of oil and natural gas in unconventional reservoirs, such as shale, coalbeds, and tight sands. During hydraulic fracturing, specially engineered fluids containing chemical additives and proppant are pumped under high pressure into the well to create and hold open fractures...
Natural gas plays a key role in our nation’s clean energy future. Recent advances in drilling technologies—including horizontal drilling and hydraulic fracturing—have made vast reserves of natural gas economically recoverable in the US. Responsible development of America’s oil and gas resources offers important economic, energy security, and environmental benefits. Hydraulic fracturing is a well stimulation technique used to maximize production of oil and natural gas in unconventional reservoirs, such as shale, coalbeds, and tight sands. During hydraulic fracturing, specially engineered fluids containing chemical additives and proppant are pumped under high pressure into the well to create and hold open fractures...
Sequestration of carbon dioxide (CO2) in depleted oil reservoirs is one of the viable options for carbon management. This paper describes the preliminary modeling and flow simulation part of a DOE sponsored CO2 sequestration project. The main objective of the project is to understand the feasibility of long term sequestration of CO2 in a depleted oil reservoir through a field demonstration experiment. Before the actual CO2 injection begins, it was necessary to determine feasibility of injection. Advanced geologic modeling and flow simulation techniques were used to develop a model for the proposed target interval. A geologic model was developed using data available from well logs and cores. Subsequently, porous...
Sequestration of carbon dioxide (CO2) in depleted oil reservoirs is one of the viable options for carbon management. This paper describes the preliminary modeling and flow simulation part of a DOE sponsored CO2 sequestration project. The main objective of the project is to understand the feasibility of long term sequestration of CO2 in a depleted oil reservoir through a field demonstration experiment. Before the actual CO2 injection begins, it was necessary to determine feasibility of injection. Advanced geologic modeling and flow simulation techniques were used to develop a model for the proposed target interval. A geologic model was developed using data available from well logs and cores. Subsequently, porous...
This paper proposes a regional and sectoral model of global final energy demand. For the main end-use sectors of consumption (industrial, commercial and public services, residential and road transportation), per-capita demand is expressed as an S-shaped function of per-capita income. Other variables intervene as well, like energy prices, temperatures and technological trends. This model is applied on a panel of 101 countries and 3 aggregates (covering the whole world) and it explains fairly well past variations in sectoral, final consumption since the beginning of the 2000s. Further, the model is used to analyze the dynamics of final energy demand, by sector and in total. The main conclusion concerns the pattern...
Short-term wind power forecasting tools providing “single-valued” (spot) predictions are nowadays widely used. However, end-users may require to have additional information on the uncertainty associated to the future wind power production for performing more efficiently functions such as reserves estimation, unit commitment, trading in electricity markets, a.o. Several models for on-line uncertainty estimation have been proposed in the literature and new products from numerical weather prediction systems (ensemble predictions) have recently become available, which has increased the modelling possibilities. In order to provide efficient on-line uncertainty estimation, choices have to be made on which model and modelling...
Categories: Publication; Types: Citation; Tags: Forecasting, Modeling, Wind
In this study, we have integrated a suite of Holocene paleoclimatic proxies with mathematical modeling in an attempt to obtain a comprehensive picture of how watersheds respond to past climate change. A three-dimensional surface-water–groundwater model was developed to assess the effects of mid-Holocene climate change on water resources within the Crow Wing Watershed, Upper Mississippi Basin in north central Minnesota. The model was first calibrated to a 50 yr historical record of average annual surface-water discharge, monthly ground-water levels, and lake-level fluctuations. The model was able to reproduce reasonably well long-term historical records (1949–1999) of water-table and lake-level fluctuations across...
A mathematically linked mercury transport, speciation, kinetic, and simple biotic uptake (BIOTRANSPEC) model has been developed. An extension of the metal transport and speciation (TRANSPEC) model, BIOTRANSPEC estimates the fate and biotic uptake of inorganic (Hg(II)), elemental (Hg(0)) and organic (MeHg) forms of mercury and their species in the dissolved, colloidal (e.g., dissolved organic matter [DOM]), and particulate phases of surface aquatic systems. A pseudo-steady state version of the model was used to describe mercury dynamics in Lahontan Reservoir (near Carson City, NV, USA), where internal loading of the historically deposited mercury is remobilized, thereby maintaining elevated water concentrations....
The recovery plan for the Mexican spotted owl (Strix occidentalis lucida) recommended protection of owl nesting and roosting habitat. Descriptions of rnicrohabitat (less than or equal to-0.04 ha) characteristics associated with suitable nesting sites have been limited for the area of pine-oak forest occupied by this species in Arizona, USA. Therefore, we studied Mexican spotted owl habitat on a 585-km(2) study area on the Coconino Plateau near Flagstaff, Arizona. Mexican spotted owls nested primarily in mature (greater than or equal to45.7-cm diameter at breast height dbh) Gambel oak (Quercus gambelii; 40%) and ponderosa pine (Pines ponderosa; 37%) trees. We examined a plausible set of a priori models using both...
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The disturbance team contributes to the goals of the LandCarbon project and conducts research focusing on 3 main components: (1) monitoring disturbance patterns and their impacts on carbon cycling, (2) understanding drivers creating the patterns and impacts, and (3) using scenarios of change to project future potential disturbance patterns, their interactions with other disturbances, and subsequent impacts on carbon cycling. Key research questions driving our work include: (1) Monitoring: How can remotely sensed, field-based, and other data best be used individually and synergistically to track changes in fire occurrence in ecosystem types with long fire-return intervals and the impacts on carbon? How do disturbances...
A convective precipitation model for use in regions of complex terrain has been developed and applied to the Gunnison River Basin in southwestern Colorado. Spring snowfall in the Rocky Mountain region often has a significant convective component which orographic precipitation models are unable to simulate. Additionally, summertime precipitation is predominately convective in this area and is responsible for a large portion of summer streamflow variability. Streamflow typically increases by 50 to 100 percent of baseflow for moderate rainfall events for periods of up to one week. Larger precipitation episodes can produce peak discharges that exceed the spring snowmelt peaks. Convective precipitation also is important...
Ecological processes of low-productivity ecosystems have long been considered to be driven by abiotic controls with biotic interactions playing an insignificant role. However, existing studies present conflicting evidence concerning the roles of these factors, in part due to the short temporal extent of most data sets and inability to test indirect effects of environmental variables modulated by biotic interactions. Using structural equation modeling to analyze 65 years of perennial vegetation change in the Sonoran Desert, we found that precipitation had a stronger positive effect on recruitment beneath existing canopies than in open microsites due to reduced evaporation rates. Variation in perennial canopy cover...
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Description of Work U.S. Geological Survey (USGS) will expand the online availability of geospatial data to monitor the presence and extent of invasive species in wetlands, coastal areas and other sensitive habitats. USGS is working with the Great Lakes Observing System collaboration and other data sharing efforts across the Great Lakes to compile the data into a user friendly format that is accessible on line. Elevation data will be expanded in the Great Lakes Basin using a collaborative to support the GLRI. This information would support invasive species monitoring, wetland inventory, and habitat restoration. USGS will work with the Great Lakes Observing System and other data sharing efforts to make USGS geospatial...
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Data collection, along with hydraulic and fluvial egg transport modeling, were completed along a 70.9-mile reach of the Ohio River between Markland Locks and Dam and McAlpine Locks and Dam. Data were collected during two surveys: October 27–November 4, 2016, and June 26–29, 2017. Water-quality data collected in this reach included surface measurements and vertical profiles of water temperature, specific conductance, pH, dissolved oxygen, turbidity, relative chlorophyll, and relative phycocyanin. Streamflow and velocity data were collected simultaneously with the water-quality data at cross sections and along longitudinal lines (corresponding to the water-quality surface measurements) and at selected stationary locations...
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This U.S. Geological Survey (USGS) data release presents the geospatial data used to assess the hydrologic and soil resources of the Organ Mountains-Desert Peaks National Monument managed by the U.S. Bureau of Land Management (BLM) in Doña Ana County, New Mexico. The USGS, in cooperation with the BLM, conducted a study to assess the hydrologic and soil resources and potential effects of infrastructure and grazing within the monument area. Publicly available data as well as data provided by the BLM were used to assess these resources and effects and to identify data gaps in the monument area. The input and output files for the Rangeland Hydrologic Erosion Model are also included in this data release. This model was...
Observed water temperatures from 1980-2019 were compiled for 5,584 lakes in Minnesota and Wisconsin (USA). A subset of these data were used as calibration for process-based models on some lakes (see "pball" models). The data are formatted as a single csv (comma separated values) file with attributes corresponding to the unique combination of lake identifier, time, and depth. Data came from a variety of sources, including the Water Quality Portal, the North Temperate Lakes Long-Term Ecological Research Project, and digitized temperature records from the MN Department of Natural Resources. Upper and Lower Red Lake data were filtered out of this release.
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The dataset represents the work of multiple states and Federal agencies as part of the US Gap Analysis and LandFire programs. Multi-season satellite imagery (Landsat ETM+) from 1999-2001 were used in conjunction with digital elevation model (DEM) derived datasets (e.g. elevation, landform) to model natural and semi-natural vegetation. The minimum mapping unit for this dataset is approximately 1 acre. Landcover classes are drawn from NatureServe's Ecological System concept. Five-hundred and fourty-four land cover classes composed of 12 cultural and 532 Natural/Semi-natural types are described. Land cover classes were mapped with a variety of techniques including decision tree classifiers, terrian modeling, inductive...
map background search result map search result map Geospatial Information for decision support in AOCs and ecosystems Ecosystem disturbances monitoring an modeling Humpback Chub and Rainbow Trout Joint Mark-Recapture Data and Model, Colorado River, Arizona BLM REA COP 2010 NatureServe National Landcover (v27) InterMountainBasinsMontaneSagebrushSteppe_NatureServe_DIST_30m Geodatabase of files associated with the Assessment of Soil and Water Resources in The Organ Mountains-Desert Peaks National Monument, New Mexico Process-based water temperature predictions in the Midwest US: 3 Temperature observations Geospatial data and models for the Simulation of Hypothetical Bighead Carp Egg and Larvae Development and Transport in the Ohio River between Markland Locks and Dam and McAlpine Locks and Dam, Kentucky and Indiana, by use of the Fluvial Egg Drift Simulator Exploring the exceptional performance of a deep learning stream temperature model and the value of streamflow data: 1 Spatial information Exploring the exceptional performance of a deep learning stream temperature model and the value of streamflow data: 4 Models Geospatial data and models for the Simulation of Hypothetical Bighead Carp Egg and Larvae Development and Transport in the Ohio River between Markland Locks and Dam and McAlpine Locks and Dam, Kentucky and Indiana, by use of the Fluvial Egg Drift Simulator Geodatabase of files associated with the Assessment of Soil and Water Resources in The Organ Mountains-Desert Peaks National Monument, New Mexico Humpback Chub and Rainbow Trout Joint Mark-Recapture Data and Model, Colorado River, Arizona Geospatial Information for decision support in AOCs and ecosystems BLM REA COP 2010 NatureServe National Landcover (v27) InterMountainBasinsMontaneSagebrushSteppe_NatureServe_DIST_30m Process-based water temperature predictions in the Midwest US: 3 Temperature observations Exploring the exceptional performance of a deep learning stream temperature model and the value of streamflow data: 1 Spatial information Exploring the exceptional performance of a deep learning stream temperature model and the value of streamflow data: 4 Models Ecosystem disturbances monitoring an modeling