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At least 1,009 records · Page 56Linked to original sources
USGS2005

libvaxdata: VAX data format conversion routines

libvaxdata provides a collection of routines for converting numeric data-integer and floating-point-to and from the formats used on a Digital Equipment Corporation1 (DEC) VAX 32-bit minicomputer (Brunner, 1991). Since the VAX numeric data formats are inherited from those used on a DEC PDP-11 16-bit minicomputer, these routines can be used to convert PDP-11 data as well. VAX numeric data formats are also the default data formats used on DEC Alpha 64-bit minicomputers running OpenVMS The libvaxdata routines are callable from Fortran or C. They require that the caller use two's-complement format for integer data and IEEE 754 format (ANSI/IEEE, 1985) for floating-point data. They also require that the 'natural' size of a C int type (integer) is 32 bits. That is the case for most modern 32-bit and 64-bit computer systems. Nevertheless, you may wish to consult the Fortran or C compiler documentation on your system to be sure. Some Fortran compilers support conversion of VAX numeric data on-the-fly when reading or writing unformatted files, either as a compiler option or a run-time I/O option. This feature may be easier to use than the libvaxdata routines. Consult the Fortran compiler documentation on your system to determine if this alternative is available to you. 1Later Compaq Computer Corporation, now Hewlett-Packard Company

Open-File Report↗
USGS2006

Summary of available hydrogeologic data for the northeast portion of the alluvial aquifer at Louisville, Kentucky

The hydrogeologic characteristics of the unconsolidated glacial outwash sand and gravel deposits that compose the northeast portion of the alluvial aquifer at Louisville, Kentucky, indicate a prolific water-bearing formation with approximately 7 billion gallons of ground-water storage and an estimated sustainable yield of over 280 million gallons per day. This abundance of ground water and the need to properly develop and manage this resource has prompted many past investigations (since 1956), which have produced reports, maps, and data files covering a variety of topics relative to the movement, availability, and use of ground water in this area. These data have been compiled into a single report to assist in future development and use of the ground-water resources. Available ground-water data for the alluvial aquifer at Louisville, Kentucky, from Beargrass Creek to Harrods Creek, were compiled from the U.S. Geological Survey National Water Information System and the Kentucky Groundwater Data Repository. Data contained in these databases include ground-water well-construction details and historical ground-water levels, drillers' logs, and water-quality information. Additional data and information were gathered from project files at the U.S. Geological Survey--Kentucky Water Science Center and files at the Louisville Water Company. Information contained in these files included data from area pumping tests describing aquifer characteristics and ground-water flow. Data describing current conditions of the ground-water system in the northeast portion of the alluvial aquifer also are included. Ground-water levels from a network of observation wells show recent trends in the flow system, and information from the Kentucky Division of Water-Groundwater Branch lists current permitted ground-water withdrawals in the area.

Open-File Report↗
USGS2006

Creation of GIS compatible, historic detailed soil data sets for the Collier and Miami-Dade Counties, Florida

When soils data are in digital format compatible with geographic information systems (GIS), a wide variety of analyses and display capabilities are afforded. Detailed information on soils that may be important to Everglades ecosystem restoration has been created in hardcopy form using traditional soils mapping techniques. However, accurate conversion of these analogue geographic data to GIS compatible information is a complicated process. Because detailed digital soils data for Southern Florida were not yet available from the US Department of Agriculture, the U.S. Geological Survey (USGS) Eastern Geographic Science Center (EGSC) developed a means for digitizing and attributing historic soil survey data for GIS analysis. This report documents that process and the two soil survey datasets created through it, one for Collier and one for Miami-Dade Counties in Florida. First, the sources for the soils data are described. Then the approach used to determine how data would be collected and organized is provided, followed by details of the spatial data collection and attribute data encoding.

Florida↗
USGS2006

Aqueous geochemical data from the analysis of stream-water samples collected in June and July 2005 — Taylor Mountains 1:250,000 scale quadrangle, Alaska

We report on the chemical analysis of water samples collected from the Taylor Mountains 1:250,000-scale quadrangle. Parameters for which data are reported include pH, conductivity, water temperature, major cation and anion concentrations, trace-element concentrations, and dissolved organic-carbon concentrations. Samples were collected as part of a multiyear U.S. Geological Survey project "Geologic and Mineral Deposit Data for Alaskan Economic Development." Data presented here are from samples collected in June and July of 2005. The data are being released at this time with minimal interpretation. This is the second release of aqueous geochemical data from this project; 2004 aqueous geochemical data were published previously ( Wang and others, 2006 ). The data in this report augment but do not duplicate or supersede the previous data release. Site selection was based on a regional sampling strategy that focused on first- and second-order drainages. Water sample site selection was based on landscape parameters that included physiography, wetland extent, lithological changes, and a cursory field review of mineralogy from pan concentrates. Stream water in the Taylor Mountians quadrangle is dominated by bicarbonate (HCO 3- ), though in a few samples more than 50 percent of the anionic charge can be attributed to sulfate (SO 4 2- ). The major-cation chemistry ranges from Ca 2+ /Mg 2+ dominated to a mix of Ca 2+ /Mg 2+ /Na + +K + . In general, good agreement was found between the major cations and anions in the duplicate samples. Many trace elements in these samples were at or near the analytical method detection limit, but good agreement was found between duplicate samples for elements with detectable concentrations. With the exception of a total mercury concentration of 0.33 ng/L detected in a field blank, field blank major-ion and trace-elements concentrations were below detection.

Alaska↗
USGS2007

Data collected to support monitoring of constructed emergent sandbar habitat on the Missouri River downstream from Gavins Point Dam, South Dakota and Nebraska, 2004-06

The U.S. Army Corps of Engineers has constructed emergent sandbar habitat on sections of the Missouri River bordering South Dakota and Nebraska downstream from Gavins Point Dam to create and enhance habitat for threatened and endangered bird species. Two areas near river miles 761.3 and 769.8 were selected for construction of emergent sandbar habitat. Pre- and postconstruction data were collected by the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, to evaluate the success of the habitat management techniques. Data collected include pre- and postconstruction channel-geometry data (bathymetric and topographic) for areas upstream from, downstream from, and within each construction site. Water-velocity data were collected for selected parts of the site near river mile 769.8. Instruments and methods used in data collection, as well as quality-assurance and quality-control measures, are described. Geospatial channel-geometry data are presented for transects of the river channel as cross sections and as geographical information system shapefiles. Geospatial land-surface elevation data are provided for part of each site in the form of a color-shaded relief map. Geospatial water-velocity data also are provided as color-shaded maps and geographical information system shapefiles.

Nebraska, South Dakota↗
USGS2007

Database Dictionary for Ethiopian National Ground-Water DAtabase (ENGDA) Data Fields

Introduction This document describes the data fields that are used for both field forms and the Ethiopian National Ground-water Database (ENGDA) tables associated with information stored about production wells, springs, test holes, test wells, and water level or water-quality observation wells. Several different words are used in this database dictionary and in the ENGDA database to describe a narrow shaft constructed in the ground. The most general term is borehole, which is applicable to any type of hole. A well is a borehole specifically constructed to extract water from the ground; however, for this data dictionary and for the ENGDA database, the words well and borehole are used interchangeably. A production well is defined as any well used for water supply and includes hand-dug wells, small-diameter bored wells equipped with hand pumps, or large-diameter bored wells equipped with large-capacity motorized pumps. Test holes are borings made to collect information about the subsurface with continuous core or non-continuous core and/or where geophysical logs are collected. Test holes are not converted into wells. A test well is a well constructed for hydraulic testing of an aquifer in order to plan a larger ground-water production system. A water-level or water-quality observation well is a well that is used to collect information about an aquifer and not used for water supply. A spring is any naturally flowing, local, ground-water discharge site. The database dictionary is designed to help define all fields on both field data collection forms (provided in attachment 2 of this report) and for the ENGDA software screen entry forms (described in Litke, 2007). The data entered into each screen entry field are stored in relational database tables within the computer database. The organization of the database dictionary is designed based on field data collection and the field forms, because this is what the majority of people will use. After each field, however, the ENGDA database field name and relational database table is designated; along with the ENGDA screen entry form(s) and the ENGDA field form (attachment 2). The database dictionary is separated into sections. The first section, Basic Site Data Fields, describes the basic site information that is similar for all of the different types of sites. The remaining sections may be applicable for only one type of site; for example, the Well Drilling and Construction Data Fields and Lithologic Description Data Fields are applicable to boreholes and not to springs. Attachment 1 contains a table for conversion from English to metric units. Attachment 2 contains selected field forms used in conjunction with ENGDA. A separate document, 'Users Reference Manual for the Ethiopian National Ground-Water DAtabase (ENGDA),' by David W. Litke was developed as a users guide for the computer database and screen entry. This database dictionary serves as a reference for both the field forms and the computer database. Every effort has been made to have identical field names between the field forms and the screen entry forms in order to avoid confusion.

Open-File Report↗
USGS2008

Documentation of data collection in Currituck Sound, North Carolina and Virginia, 2006-2007

During 2006 and 2007, scientists from Elizabeth City State University, North Carolina Estuarine Research Reserve, the U.S. Fish and Wildlife Service, and the U.S. Geological Survey collected hydrologic and water-quality data at nine sites in and around Currituck Sound. Hydrologic and water-quality data were collected at five tributary sites--the Northwest River near Moyock, Tull Creek near Currituck, and Intracoastal Waterway near Coinjock in North Carolina, and the Albemarle and Chesapeake Canal near Princess Anne, and the North Landing River near Creeds in Virginia. In addition, data were collected at one site at the mouth of Currituck Sound (Currituck Sound at Point Harbor, North Carolina). Only water-quality data were collected at three sites in Currituck Sound and Back Bay-Currituck Sound near Jarvisburg, and Upper Currituck Sound near Corolla in North Carolina, and Back Bay near Back Bay in Virginia. The hydrologic data included water elevation and velocity, and discharge. The water-quality data included discrete samples and continuous measurements of water temperature, specific conductance, dissolved oxygen, pH, turbidity, and chlorophyll a. The hydrologic and water-quality data collected for this study were quality assured by the U.S. Geological Survey and stored in the National Water Information System database. The data collected for this project are being used to develop an unsteady multidimensional hydrodynamic and water-quality model of Currituck Sound by the U.S. Army Corps of Engineers. The purpose of this model is to provide the basis for planning and the development of best-management practices and restoration projects for Currituck Sound and its tributaries.

North Carolina, Virginia↗
USGS2010

Method description, quality assurance, environmental data, and other Information for analysis of pharmaceuticals in wastewater-treatment-plant effluents, streamwater, and reservoirs, 2004-2009

Abstract Wastewater-treatment-plant (WWTP) effluents are a demonstrated source of pharmaceuticals to the environment. During 2004-09, a study was conducted to identify pharmaceutical compounds in effluents from WWTPs (including two that receive substantial discharges from pharmaceutical formulation facilities), streamwater, and reservoirs. The methods used to determine and quantify concentrations of seven pharmaceuticals are described. In addition, the report includes information on pharmaceuticals formulated or potentially formulated at the two pharmaceutical formulation facilities that provide substantial discharge to two of the WWTPs, and potential limitations to these data are discussed. The analytical methods used to provide data on the seven pharmaceuticals (including opioids, muscle relaxants, and other pharmaceuticals) in filtered water samples also are described. Data are provided on method performance, including spike data, method detection limit results, and an estimation of precision. Quality-assurance data for sample collection and handling are included. Quantitative data are presented for the seven pharmaceuticals in water samples collected at WWTP discharge points, from streams, and at reservoirs. Occurrence data also are provided for 19 pharmaceuticals that were qualitatively identified. Flow data at selected WWTP and streams are presented. Between 2004-09, 35-38 effluent samples were collected from each of three WWTPs in New York and analyzed for seven pharmaceuticals. Two WWTPs (NY2 and NY3) receive substantial inflows (greater than 20 percent of plant flow) from pharmaceutical formulation facilities (PFF) and one (NY1) receives no PFF flow. Samples of effluents from 23 WWTPs across the United States were analyzed once for these pharmaceuticals as part of a national survey. Maximum pharmaceutical effluent concentrations for the national survey and NY1 effluent samples were generally less than 1 ug/L. Four pharmaceuticals (methadone, oxycodone, butalbital and metaxalone) in samples of NY3 effluent had median concentrations ranging from 3.4 to greater than 400 ug/L. Maximum concentrations of oxycodone (1,700 ug/L) and metaxalone (3,800 ug/L) in samples from NY3 effluent exceeded 1,000 ug/L. Three pharmaceuticals (butalbital, carisoprodol, and oxycodone) in samples of NY2 effluent had median concentrations ranging from 2 to 11 ug/L. These findings suggest that current 2 manufacturing practices at these PFFs can result in pharmaceutical concentrations from 10 to 1,000 times higher than those typically found in WWTP effluents.

Open-File Report↗
USGS2011

Helicopter electromagnetic and magnetic geophysical survey data, Swedeburg and Sprague study areas, eastern Nebraska, May 2009

This report is a release of digital data from a helicopter electromagnetic and magnetic survey conducted by Fugro Airborne Surveys in areas of eastern Nebraska as part of a joint hydrologic study by the Lower Platte North and Lower Platte South Natural Resources Districts, and the U.S. Geological Survey. The survey flight lines covered 1,418.6 line km (882 line mile). The survey was flown from April 22 to May 2, 2009. The objective of the contracted survey was to improve the understanding of the relation between surface water and groundwater systems critical to developing groundwater models used in management programs for water resources. The electromagnetic equipment consisted of six different coil-pair orientations that measured resistivity at separate frequencies from about 400 hertz to about 140,000 hertz. The electromagnetic data were converted to georeferenced electrical resistivity grids and maps for each frequency that represent different approximate depths of investigation for each survey area. The electrical resistivity data were input into a numerical inversion to estimate resistivity variations with depth. In addition to the electromagnetic data, total field magnetic data and digital elevation data were collected. Data released in this report consist of flight line data, digital grids, digital databases of the inverted electrical resistivity with depth, and digital maps of the apparent resistivity and total magnetic field. The range of subsurface investigation is comparable to the depth of shallow aquifers. The survey areas, Swedeburg and Sprague, were chosen based on results from test flights in 2007 in eastern Nebraska and needs of local water managers. The geophysical and hydrologic information from U.S. Geological Survey studies are being used by resource managers to develop groundwater resource plans for the area.

Open-File Report↗
USGS2011

Aqueous geochemical data from the analysis of stream-water samples collected in June and July 2006 — Taylor Mountains 1:250,000-scale quadrangle, Alaska

We report on the chemical analysis of water samples collected from the Taylor Mountains 1:250,000-scale quadrangle, Alaska. Parameters for which data are reported include pH, conductivity, water temperature, major cation and anion concentrations, trace-element concentrations, and dissolved organic-carbon concentrations. Samples were collected as part of a multiyear U.S. Geological Survey project entitled ?Geologic and Mineral Deposit Data for Alaskan Economic Development.? Data presented here are from samples collected in June and July 2006. The data are being released at this time with minimal interpretation. This is the third release of aqueous geochemical data from this project; aqueous geochemical data from samples collected in 2004 and 2005 were published previously. The data in this report augment but do not duplicate or supersede the previous data release. Site selection was based on a regional sampling strategy that focused on first- and second-order drainages. Water sample site selection was based on landscape parameters that included physiography, wetland extent, lithological changes, and a cursory field review of mineralogy from pan concentrates. Stream water in the Taylor Mountains quadrangle is dominated by bicarbonate (HCO3-), although in a few samples more than 50 percent of the anionic charge can be attributed to sulfate (SO42-). The major-cation chemistry ranges from Ca2+/Mg2+ dominated to a mix of Ca2+/Mg2+/Na++K+. Generally, good agreement was found between the major cations and anions in the duplicate samples. Many trace elements in these samples were at or near the analytical method detection limit, but good agreement was found between duplicate samples for elements with detectable concentrations. All field blank major-ion and trace-element concentrations were below detection.

Alaska↗
USGS2012

waterData--An R package for retrieval, analysis, and anomaly calculation of daily hydrologic time series data, version 1.0

Hydrologic time series data and associated anomalies (multiple components of the original time series representing variability at longer-term and shorter-term time scales) are useful for modeling trends in hydrologic variables, such as streamflow, and for modeling water-quality constituents. An R package, called waterData, has been developed for importing daily hydrologic time series data from U.S. Geological Survey streamgages into the R programming environment. In addition to streamflow, data retrieval may include gage height and continuous physical property data, such as specific conductance, pH, water temperature, turbidity, and dissolved oxygen. The package allows for importing daily hydrologic data into R, plotting the data, fixing common data problems, summarizing the data, and the calculation and graphical presentation of anomalies.

Open-File Report↗
USGS2013

Baseline data for evaluating development trajectory and provision of ecosystem services of created fringing oyster reefs in Vermilion Bay, Louisiana

Understanding the time frame in which ecosystem services (that is, water quality maintenance, shoreline protection, habitat provision) are expected to be provided is important when restoration projects are being designed and implemented. Restoration of three-dimensional shell habitats in coastal Louisiana and elsewhere presents a valuable and potentially self-sustaining approach to providing shoreline protection, enhancing nekton habitat, and providing water quality maintenance. As with most restoration projects, the development of expected different ecosystem services often occurs over varying time frames, with some services provided immediately and others taking longer to develop. This project was designed initially to compare the provision and development of ecosystem services by created fringing shoreline reefs in subtidal and intertidal environments in Vermilion Bay, Louisiana. Specifically, the goal was to test the null hypothesis that over time, the oyster recruitment and development of a sustainable oyster reef community would be similar at both intertidal and subtidal reef bases, and these sustainable reefs would in time provide similar shoreline stabilization, nekton habitat, and water quality services over similar time frames. Because the ecosystem services hypothesized to be provided by oyster reefs reflect long-term processes, fully testing the above-stated null hypothesis requires a longer-time frame than this project allowed. As such, this project was designed to provide the initial data on reef development and provision of ecosystem services, to identify services that may develop immediately, and to provide baseline data to allow for longer-term follow up studies tracking reef development over time. Unfortunately, these initially created reef bases (subtidal, intertidal) were not constructed as planned because of the Deepwater Horizon oil spill in April 2010, which resulted in reef duplicates being created 6 months apart. Further confounding the project were additional construction and restoration projects along the same shorelines which occurred between 2011 and June 2012. Because of constant activity near and around the reefs and continuing construction, development trajectories could not be compared among reef types at this time. This report presents the data collected at the sites over 3 years (2010–2012), describing only conditions and trends. In addition, these data provide an extensive and detailed dataset documenting initial conditions and initial ecosystem changes which will prove valuable in future data collection and analyses of reef development at this site. Data collection characterized the local water quality conditions (salinity, temperature, total suspended sediments, dissolved oxygen, chlorophyll a), adjacent marsh vegetation, soils, and shoreline position along the project shoreline at Vermilion Bay. During the study, marsh vegetation and soil characteristics were similar across the study area and did not change over time. Shoreline movement indicated shoreline loss at all sites, which varied by reefs. Water quality conditions followed expected seasonal patterns for this region, and no significant nonseasonal changes were measured throughout the study period. Despite oyster recruitment in fall 2010 and 2011, few if any oysters survived from the 2010 year class to 2012. At the last sampling of this project, some oysters recruited in fall 2011 survived through 2012, resulting in an on-reef density of 18.3 ± 2.1 individuals per square meter (mean size: 85.6 ± 2.2 millimeters). Because project goals were to compare reef development and provision of ecosystem services over time, as well as many of the processes identified for monitoring reflect long-term processes, results and data are presented only qualitatively, and trends or observations should be interpreted cautiously at this point. Measurable system responses to reef establishment require more time than was available for this study. These data provide a valuable baseline that can be ultimately used to help inform site selections for future restoration projects as well to further investigate the development trajectories of ecosystem provision of created reefs in this region.

Louisiana↗
USGS2014

Airborne geophysical surveys conducted in western Nebraska, 2010: contractor reports and data

This report contains three contractor reports and data files for an airborne electromagnetic survey flown from June 28 to July 7, 2010. The first report; “SkyTEM Survey: Nebraska, USA, Data” describes data aquisition and processing from a time-domain electromagnetic and magnetic survey performed by SkyTEM Canada, Inc. (the North American SkyTEM subsidiary), in western Nebraska, USA. Digital data for this report are given in Appendix 1. The airborne geophysical data from the SkyTEM survey subsequently were processed and inverted by Aarhus Geophysics ApS, Aarhus, Denmark, to produce resistivity depth sections along each flight line. The result of that processing is described in two reports presented in Appendix 2, “Processing and inversion of SkyTEM data from USGS Area UTM–13” and “Processing and inversion of SkyTEM data from USGS Area UTM–14.” Funding for these surveys was provided by the North Platte Natural Resources District, the South Platte Natural Resources District, and the Twin Platte Natural Resources District, in Scottsbluff, Sidney, and North Platte, Nebraska, respectively. Any additional information concerning the geophysical data may be obtained from the U.S. Geological Survey Crustal Geophysics and Geochemistry Science Center, Denver Colorado.

Nebraska↗
USGS2013

Integrating Federal and State data records to report progress in establishing agricultural conservation practices on Chesapeake Bay farms

In response to the Executive Order for Chesapeake Bay Protection and Restoration (E.O. #13508, May 12, 2009), the U.S. Geological Survey (USGS) took on the task of acquiring and assessing agricultural conservation practice data records for U.S. Department of Agriculture (USDA) programs, and transferred those datasets in aggregated format to State jurisdictional agencies for use in reporting conservation progress to the Chesapeake Bay Program Partnership (CBP Partnership). Under the guidelines and regulations that have been developed to protect and restore water-quality in the Chesapeake Bay, the six State jurisdictions that fall within the Chesapeake Bay watershed are required to report their progress in promoting agricultural conservation practices to the CBP Partnership on an annual basis. The installation and adoption of agricultural best management practices is supported by technical and financial assistance from both Federal and State conservation programs. The farm enrollment data for USDA conservation programs are confidential, but agencies can obtain access to the privacy-protected data if they are established as USDA Conservation Cooperators. The datasets can also be released to the public if they are first aggregated to protect farmer privacy. In 2012, the USGS used its Conservation Cooperator status to obtain implementation data for conservation programs sponsored by the USDA Natural Resources Conservation Service (NRCS) and the USDA Farm Service Agency (FSA) for farms within the Chesapeake Bay watershed. Three jurisdictions (Delaware, Pennsylvania, and West Virginia) used the USGS-provided aggregated dataset to report conservation progress in 2012, whereas the remaining three jurisdictions (Maryland, New York, and Virginia) used jurisdictional Conservation Cooperator Agreements to obtain privacy-protected data directly from the USDA. This report reviews the status of conservation data sharing between the USDA and the various jurisdictions, discusses the methods that were used by the USGS in 2012 to collect and process USDA agricultural conservation data, and also documents methods that were used by the jurisdictions to integrate Federal and State data records, reduce double counting, and provide an accurate reporting of conservation practices to the CBP Partnership’s Annual Progress Review. A similar tracking, reporting, and assessment will occur in future years, as State and Federal governments and nongovernmental organizations continue to work with farmers and conservation districts to reduce the impacts of agriculture on water-quality.

Delaware; Maryland; New York; Pennsylvania;Virgini↗
USGS2014

Review and bibliometric analysis of published literature citing data produced by the Gap Analysis Program (GAP)

The Gap Analysis Program (GAP) of the U.S. Geological Survey (USGS) produces geospatial datasets providing information on land cover, predicted species distributions, stewardship (ownership and conservation status), and an analysis dataset which synthesizes the other three datasets. The intent in providing these datasets is to support the conservation of biodiversity. The datasets are made available at no cost. The initial datasets were created at the state level. More recent datasets have been assembled at regional and national levels. GAP entered an agreement with the Policy Analysis and Science Assistance branch of the USGS to conduct an evaluation to describe the effect that using GAP data has on those who utilize the datasets (GAP users). The evaluation project included multiple components: a discussion regarding use of GAP data conducted with participants at a GAP conference, a literature review of publications that cited use of GAP data, and a survey of GAP users. The findings of the published literature search were used to identify topics to include on the survey. This report summarizes the literature search, the characteristics of the resulting set of publications, the emergent themes from statements made regarding GAP data, and a bibliometric analysis of the publications. We cannot claim that this list includes all publications that have used GAP data. Given the time lapse that is common in the publishing process, more recent datasets may be cited less frequently in this list of publications. Reports or products that used GAP data may be produced but never published in print or released online. In that case, our search strategies would not have located those reports. Authors may have used GAP data but failed to cite it in such a way that the search strategies we used would have located those publications. These are common issues when using a literature search as part of an evaluation project. Although the final list of publications we identified is not comprehensive, this set of publications can be considered a sufficient sample of those citing GAP data and suitable for the descriptive analyses we conducted.

Open-File Report↗
USGS2014

Investigations into near-real-time surveying for geophysical data collection using an autonomous ground vehicle

The U.S. Geological Survey and the National Aeronautics and Space Administration are cooperatively investigating the utility of unmanned vehicles for near-real-time autonomous surveys of geophysical data collection. Initially focused on unmanned ground vehicle collection of magnetic data, this cooperative effort has brought unmanned surveying, precision guidance, near-real-time communication, on-the-fly data processing, and near-real-time data interpretation into the realm of ground geophysical surveying, all of which offer advantages over current methods of manned collection of ground magnetic data. An unmanned ground vehicle mission has demonstrated that these vehicles can successfully complete missions to collect geophysical data, and add advantages in data collection, processing, and interpretation. We view the current experiment as an initial phase in further unmanned vehicle data-collection missions, including aerial surveying.

California↗
USGS2015

An evaluation of the accuracy of modeled and computed streamflow time-series data for the Ohio River at Hannibal Lock and Dam and at a location upstream from Sardis, Ohio

Between July 2013 and June 2014, the U.S. Geological Survey (USGS) made 10 streamflow measurements on the Ohio River about 1.5 miles (mi) downstream from the Hannibal Lock and Dam (near Hannibal, Ohio) and 11 streamflow measurements near the USGS Sardis gage (station number 03114306) located approximately 2.4 mi upstream from Sardis, Ohio. The measurement results were used to assess the accuracy of modeled or computed instantaneous streamflow time series created and supplied by the USGS, U.S. Army Corps of Engineers (USACE), and National Weather Service (NWS) for the Ohio River at Hannibal Lock and Dam and (or) at the USGS streamgage. Hydraulic or hydrologic models were used to create the modeled time series; index-velocity methods or gate-opening ratings coupled with hydropower operation data were used to create the computed time series. The time step of the various instantaneous streamflow time series ranged from 15 minutes to 24 hours (once-daily values at 12:00 Coordinated Universal Time [UTC]). The 15-minute time-series data, computed by the USGS for the Sardis gage, also were downsampled to 1-hour and 24-hour time steps to permit more direct comparisons with other streamflow time series. To facilitate comparisons between measurement results and time-series data, streamflows corresponding to the times of the streamflow measurements were computed from the time-series data by time-based linear interpolation. Prior to doing interpolations, measurement times for the Hannibal Lock and Dam location were adjusted for traveltime to account for the fact that the streamflow measurements were made about 1.5 mi downstream from the location corresponding to the modeled/computed time-series data. Measured and interpolated streamflows were tabulated along with residuals (the difference between measured and interpolated streamflows) and selected summary statistics. Overall, streamflows interpolated from the USGS computed 15-minute time-series data (hereafter referred to as the USGS 15-minute time-series data) had the smallest root-mean-square error (RMSE) (3,939 cubic feet per second [ft 3 /s]) and the second smallest mean absolute residual (2,636 ft 3 /s), whereas streamflows interpolated from the USACE 12 UTC time series had the largest RMSE (14,590 ft 3 /s) and the largest mean absolute residual (10,800 ft 3 /s). The larger RMSEs for streamflows interpolated from the USACE 12 UTC time series likely resulted in part from the coarser time step of that time series. Streamflows interpolated from the USGS downsampled 1-hour time series had the second smallest RMSE (4,025 ft 3 /s) and the smallest mean absolute residual (2,600 ft 3 /s). Somewhat surprisingly, streamflows interpolated from the NWS 6-hour model time series had the third smallest RMSE (4,483 ft 3 /s) and mean absolute residual (4,050 ft 3 /s) in spite of being determined from a time series with a coarser time step than the USACE 1-hour modeled and computed time series. Measured streamflows at the Sardis gage and at the Hannibal Lock and Dam measurement location were plotted versus residuals (expressed as a percentage of the measured streamflows) of corresponding interpolated time-series streamflow values. Results for each of the time series exhibited some anomaly, possibly indicating the need and (or) potential for improvement in the streamflow computational/modeling processes. Streamflow hydrographs were plotted for modeled/computed time series for the Ohio River near the USGS Sardis gage and the Ohio River at the Hannibal Lock and Dam. In general, the time series at these two locations compared well. Some notable differences include the exclusive presence of short periods of negative streamflows in the USGS 15-minute time-series data for the gage on the Ohio River above Sardis, Ohio, and the occurrence of several peak streamflows in the USACE gate/hydropower time series for the Hannibal Lock and Dam that were appreciably larger than corresponding peaks in the other time series, including those modeled/computed for the downstream Sardis gage

Ohio↗
USGS2021

U.S. Geological Survey Great Lakes Science Forum—Summary of remaining data and science needs and next steps

A U.S. Geological Survey-led assessment of data gaps and science needs across the Great Lakes ecosystem indicated the following: • Expanded data collection or monitoring would provide basic ecosystem, social, and public health data to manage the Great Lakes system and to develop and test models and decision support tools. • New science and advanced technologies (for example, sensors and high-performance computing capability) would improve the understanding of critical threats, such as harmful algae blooms and high-water levels. Although there is significant scientific knowledge in specific areas or for specific topics, managers could use improved models and decision support tools, strengthened by extensive data collection and developed at multiple scales, to better inform decision making in the future. Enhanced coordination of agency efforts and associated data collection across data types (for example, prey fish populations and water levels) is needed to effectively manage the Great Lakes. This report highlights the data gaps; benefits of better, more structured coordination; and areas of concern specifically related to data collection/measurement and science efforts. It summarizes and analyzes stakeholder feedback and information from review of scientific literature. Finally, the report outlines steps necessary to create an integrated Great Lakes science plan.

Open-File Report↗