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Sample records for discharge powder river

  1. Assessing the Erosion Potential of Coal Bed Methane Surface Water Discharges in the Powder River Basin, WY

    NASA Astrophysics Data System (ADS)

    Wilkerson, G. V.

    2003-12-01

    The mining of coal bed methane (CBM) in the Powder River (structural) basin (PRB) in northeast Wyoming has been an economic windfall for Wyoming. However, a critical issue in the production of CBM is the removal and disposition of the associated product water. The process of extracting coal bed methane involves drilling a well into a coal seam and then pumping water out of the well. Among other things, the pressure gradient created by pumping water out the well causes the methane to flow towards the well where it is retrieved. As a result of CBM development, many ephemeral streams in the Powder River (structural) basin (PRB) in northeast Wyoming are seeing a significant increase in water discharges. A potential consequence of the increased discharges is accelerated channel erosion. The Wyoming Department of Environmental Quality (WDEQ) issues permits that legally allow CBM developers to discharge CBM water into channels and therefore they must be able to anticipate how much water can be discharged into a channel before there is a significant risk of accelerated erosion. Erosion Potential (EP) Modeler is a GIS based program that was developed to facilitate the calculation of an index that can be used to assess the potential for accelerated channel erosion in response to increased discharges in a channel. In general, EP Modeler was developed to help those responsible for or concerned about watersheds affected by CBM development in the PRB. In particular, EP Modeler was developed to assist WDEQ personnel formulate appropriate management decisions associated with the National Pollution Discharge Elimination System permitting process. EP Modeler estimates pre- and post-CBM development equilibrium channel widths and reports the percent change in width as an index of the potential for channel erosion. Pre- and post-CBM development channel widths are computed as a function of the bankfull discharge and the sum of bankfull discharge and anticipated CBM product water

  2. Effects of coal-bed methane discharge waters on the vegetation and soil ecosystem in Powder River Basin, Wyoming

    USGS Publications Warehouse

    Stearns, M.; Tindall, J.A.; Cronin, G.; Friedel, M.J.; Bergquist, E.

    2005-01-01

    Coal-bed methane (CBM) co-produced discharge waters in the Powder River Basin of Wyoming, resulting from extraction of methane from coal seams, have become a priority for chemical, hydrological and biological research during the last few years. Soil and vegetation samples were taken from affected and reference sites (upland elevations and wetted gully) in Juniper Draw to investigate the effects of CBM discharge waters on soil physical and chemical properties and on native and introduced vegetation density and diversity. Results indicate an increase of salinity and sodicity within local soil ecosystems at sites directly exposed to CBM discharge waters. Elevated concentrations of sodium in the soil are correlated with consistent exposure to CBM waters. Clay-loam soils in the study area have a much larger specific surface area than the sandy soils and facilitate a greater sodium adsorption. However, there was no significant relation between increasing water sodium adsorption ratio (SAR) values and increasing sediment SAR values downstream; however, soils exposed to the CBM water ranged from the moderate to severe SAR hazard index. Native vegetation species density was highest at the reference (upland and gully) and CBM affected upland sites. The affected gully had the greatest percent composition of introduced vegetation species. Salt-tolerant species had the greatest richness at the affected gully, implying a potential threat of invasion and competition to established native vegetation. These findings suggest that CBM waters could affect agricultural production operations and long-term water quality. ?? Springer 2005.

  3. Determining erodibility, critical shear stress, and allowable discharge estimates for cohesive channels: case study in the Powder River Basin of Wyoming

    SciTech Connect

    Thoman, R.W.; Niezgoda, S.L.

    2008-12-15

    The continuous discharge of coalbed natural gas-produced (CBNG-produced) water within ephemeral, cohesive channels in the Powder River Basin (PRB) of Wyoming can result in significant erosion. A study was completed to investigate channel stability in an attempt to correlate cohesive soil properties to critical shear stress. An in situ jet device was used to determine critical shear stress (tau{sub c}) and erodibility (k{sub d}); cohesive soil properties were determined following ASTM procedures for 25 reaches. The study sites were comprised of erodible to moderately resistant clays with tau{sub c} ranging from 0.11 to 15.35 Pa and k{sub d} ranging from 0.27 to 2.38 cm{sup 3}/N s. A relationship between five cohesive soil characteristics and tau{sub c} was developed and presented for use in deriving tau{sub c} for similar sites. Allowable discharges for CBNG-produced water were also derived using tau{sub c} and the tractive force method. An increase in the allowable discharge was found for channels in which vegetation was maintained. The information from this case study is critical to the development of a conservative methodology to establish allowable discharges while minimizing flow-induced instability.

  4. Desensitizing nano powders to electrostatic discharge ignition

    SciTech Connect

    Steelman, Ryan; Clark, Billy; Pantoya, Michelle L.; Heaps, Ronald J.; Daniels, Michael A.

    2015-08-01

    Electrostatic discharge (ESD) is a main cause for ignition in powder media ranging from grain silos to fireworks. Nanoscale particles are orders of magnitude more ESD ignition sensitive than their micron scale counterparts. This study shows that at least 13 vol. % carbon nanotubes (CNT) added to nano-aluminum and nano-copper oxide particles (nAl + CuO) eliminates ESD ignition sensitivity. The CNT act as a conduit for electric energy and directs electric charge through the powder to desensitize the reactive mixture to ignition. For nanoparticles, the required CNT concentration for desensitizing ESD ignition acts as a diluent to quench energy propagation.

  5. Increasing river discharge to the Arctic Ocean.

    PubMed

    Peterson, Bruce J; Holmes, Robert M; McClelland, James W; Vörösmarty, Charles J; Lammers, Richard B; Shiklomanov, Alexander I; Shiklomanov, Igor A; Rahmstorf, Stefan

    2002-12-13

    Synthesis of river-monitoring data reveals that the average annual discharge of fresh water from the six largest Eurasian rivers to the Arctic Ocean increased by 7% from 1936 to 1999. The average annual rate of increase was 2.0 +/- 0.7 cubic kilometers per year. Consequently, average annual discharge from the six rivers is now about 128 cubic kilometers per year greater than it was when routine measurements of discharge began. Discharge was correlated with changes in both the North Atlantic Oscillation and global mean surface air temperature. The observed large-scale change in freshwater flux has potentially important implications for ocean circulation and climate.

  6. Relating river discharges to salinity changes

    NASA Astrophysics Data System (ADS)

    Xie, X.; Liu, W. T.

    2014-12-01

    New river discharge data are brought together with spacebased sea surface salinity measurements by Aquarius and SMOS to demonstrate the role of river discharge in salinity changes near three river mouths: the Mississippi, the Ganges, and the Amazon. The characteristics of the seasonal cycle and the year-to-year changes of the river runoff are described. Various versions of the satellite salinity data are compared. The relative roles of river discharge, surface water flux, and horizontal advection in changing surface salinity in regions near the river mouths are examined. Satellite measurements of SSS clearly track movements of the fresh water from river discharges. Besides the river discharge, E-P plays an important role in the seasonal salinity variation near the Ganges and Irrawaddy River mouths. For the Mississippi and Amazon river mouths, central and eastern ITCZ, E-P contributes very little to the salinity seasonal change. In the central and eastern ITCZ, contribution of advection to the salinity tendency is clearly identified. Both salinity and salinity tendency are dominated by semi-annual cycle in the Atlantic ITCZ between 5ºN to 9ºN, whereas annual cycle dominates at other latitudes.

  7. Accuracy of the river discharge measurement

    NASA Astrophysics Data System (ADS)

    Chung Yang, Han

    2013-04-01

    Discharge values recorded for water conservancy and hydrological analysis is a very important work. Flood control projects, watershed remediation and river environmental planning projects quite need the discharge measurement data. In Taiwan, we have 129 rivers, in accordance with the watershed situation, economic development and other factors, divided into 24 major rivers, 29 minor rivers and 79 ordinary rivers. If each river needs to measure and record these discharge values, it will be enormous work. In addition, the characteristics of Taiwan's rivers contain steep slope, flow rapidly and sediment concentration higher, so it really encounters some difficulties in high flow measurement. When the flood hazards come, to seek a solution for reducing the time, manpower and material resources in river discharge measurement is very important. In this study, the river discharge measurement accuracy is used to determine the tolerance percentage to reduce the number of vertical velocity measurements, thereby reducing the time, manpower and material resources in the river discharge measurement. The velocity data sources used in this study form Yang (1998). Yang (1998) used the Fiber-optic Laser Doppler Velocimetery (FLDV) to obtain different velocity data under different experimental conditions. In this study, we use these data to calculate the mean velocity of each vertical line by three different velocity profile formula (that is, the law of the wall, Chiu's theory, Hu's theory), and then multiplied by each sub-area to obtain the discharge measurement values and compared with the true values (obtained by the direct integration mode) to obtain the accuracy of discharge. The research results show that the discharge measurement values obtained by Chiu's theory are closer to the true value, while the maximum error is the law of the wall. The main reason is that the law of the wall can't describe the maximum velocity occurred in underwater. In addition, the results also show

  8. In situ measurements of microbially-catalyzed nitrification and nitrate reduction rates in an ephemeral drainage channel receiving water from coalbed natural gas discharge, Powder River Basin, Wyoming, USA

    USGS Publications Warehouse

    Harris, S.H.; Smith, R.L.

    2009-01-01

    Nitrification and nitrate reduction were examined in an ephemeral drainage channel receiving discharge from coalbed natural gas (CBNG) production wells in the Powder River Basin, Wyoming. CBNG co-produced water typically contains dissolved inorganic nitrogen (DIN), primarily as ammonium. In this study, a substantial portion of discharged ammonium was oxidized within 50??m of downstream transport, but speciation was markedly influenced by diel fluctuations in dissolved oxygen (> 300????M). After 300??m of transport, 60% of the initial DIN load had been removed. The effect of benthic nitrogen-cycling processes on stream water chemistry was assessed at 2 locations within the stream channel using acrylic chambers to conduct short-term (2-6??h), in-stream incubations. The highest ambient DIN removal rates (2103????mol N m- 2 h- 1) were found at a location where ammonium concentrations > 350????M. This occurred during light incubations when oxygen concentrations were highest. Nitrification was occurring at the site, however, net accumulation of nitrate and nitrite accounted for < 12% of the ammonium consumed, indicating that other ammonium-consuming processes were also occurring. In dark incubations, nitrite and nitrate consumption were dominant processes, while ammonium was produced rather than consumed. At a downstream location nitrification was not a factor and changes in DIN removal rates were controlled by nitrate reduction, diel fluctuations in oxygen concentration, and availability of electron donor. This study indicates that short-term adaptation of stream channel processes can be effective for removing CBNG DIN loads given sufficient travel distances, but the long-term potential for nitrogen remobilization and nitrogen saturation remain to be determined.

  9. Smartphone for measuring river discharge

    NASA Astrophysics Data System (ADS)

    Peña-Haro, Salvador; Lüthi, Beat; Philippe, Thomas

    2015-04-01

    Smartphones have become powerful and have extended their capacities including different types of sensors. These capabilities make them very interesting for its applications in water management. We have developed a new mobile device application for open-channel flow measurements. This app can be used to determine the flow in e.g. rivers, artificial channels, irrigation ditches, furrows, etc. The smartphone app computes the runoff by analysing a few seconds of a movie that is recorded using the smartphone camera. The runoff is calculated from the estimated water level, surface velocity and from prior knowledge on the channel geometry. The water level is determined by the separation line of image segments with and without optical flow. Via calibration of the smartphone camera position this separation line is mapped to a water level. The surface velocity is calculated using a modified method of the standard Particle Image Velocimetry method. Among the key characteristics of the method is the fact that no tracer particles are needed. There are two flavours of the app. In the first one, all the measurements are taken using the available sensors in the mobile device and all the calculations are made making only use of the device. Three results are given back: the water level, the average surface velocity and discharge. This information can be sent via SMS. In the second one, the movie is send to a central computer where more detailed calculations are made, like fine camera calibration, camera stabilization tuning, definition of the region of interest, the sub-windows for the velocity analysis can be changed, different algorithms can be chosen, etc. It also generates more detailed results. Using smartphones, measurements can be made at much lower cost, since there is no need of permanent installations, which also makes it possible to take measurements in any place.

  10. River discharge estimation through MODIS data

    NASA Astrophysics Data System (ADS)

    Tarpanelli, Angelica; Brocca, Luca; Lacava, Teodosio; Faruolo, Mariapia; Melone, Florisa; Moramarco, Tommaso; Pergola, Nicola; Tramutoli, Valerio

    2011-11-01

    River discharge is an important quantity of the hydrologic cycle because it is essential for both scientific and operational applications related to water resources management and flood risk prevention. Streamflow measurements are sparse and for few sites along natural channels and, hence, they are not able to detect adequately the complexity of variation in surface water systems. Therefore, in recent years, the possibility to obtain river discharge estimates through remote sensing monitoring has received a great interest. In this context, the capability of the MODerate resolution Imaging Spectroradiometer (MODIS) for river discharge estimation is investigated here. Thanks to a very short revisiting time interval and a moderate spatial resolution (up to 250 m), MODIS has a significant potential for mapping flooded area extent and flow dynamics. Specifically, for the estimation of river discharge, the ratio of the MODIS channel 2 reflectance values between two pixels located within and outside the river is used. Time series of daily discharge between 2006 and 2010 measured at two gauging stations located along the Upper Tiber River basin (central Italy) are employed to test the procedure. The agreement between MODIS-derived and in situ discharge time series is found to be fairly good with correlation coefficient values close to 0.8.

  11. Pulsed microwave discharges in powder mixtures: Status, problems, and prospects

    NASA Astrophysics Data System (ADS)

    Batanov, G. M.; Kossyi, I. A.

    2015-10-01

    Results of experiments on the excitation of pulsed microwave discharges by gyrotron radiation (λ = 4 mm, P 0 = 100-500 kW, τ = 1-10 ms) in the volumes and on the surfaces of metal-dielectric powder mixtures are presented. It is shown that there are two phases of discharge development: the spark phase, accompanied by a partial evaporation of the powder material, and the phase of a developed discharge, characterized by a plasma density of ˜1017 cm-3, high absorption, and high temperatures (˜5-10 kK) in a thin layer (˜0.1-0.2 mm) of plasma and vapor. It is demonstrated that the conductivity induced in the targets by UV radiation play an important role in the microwave absorption by powder grains. It is found that, in the course of the discharge, a conductive metal mesh forms in the powder volume as a result of metal evaporation. Reactions of high-temperature synthesis were initiated in various powder mixtures (Ti + B, Al + Fe2O3, Mo + B, etc.). It is shown that the reactions of high-temperature synthesis last for up to 0.1 s and are accompanied by the evaporation of powder grains and the formation of an aerosol cloud due to free expansion of reactants from the sample surface. The possibility of experimentally studying the kinetics of reactions of high-temperature synthesis is demonstrated. It is noticed that microwave discharges can be used to initiate plasmachemical reactions on the surfaces of radioparent materials in active gaseous media.

  12. Pulsed microwave discharges in powder mixtures: Status, problems, and prospects

    SciTech Connect

    Batanov, G. M. Kossyi, I. A.

    2015-10-15

    Results of experiments on the excitation of pulsed microwave discharges by gyrotron radiation (λ = 4 mm, P{sub 0} = 100–500 kW, τ = 1–10 ms) in the volumes and on the surfaces of metal-dielectric powder mixtures are presented. It is shown that there are two phases of discharge development: the spark phase, accompanied by a partial evaporation of the powder material, and the phase of a developed discharge, characterized by a plasma density of ∼10{sup 17} cm{sup –3}, high absorption, and high temperatures (∼5–10 kK) in a thin layer (∼0.1–0.2 mm) of plasma and vapor. It is demonstrated that the conductivity induced in the targets by UV radiation play an important role in the microwave absorption by powder grains. It is found that, in the course of the discharge, a conductive metal mesh forms in the powder volume as a result of metal evaporation. Reactions of high-temperature synthesis were initiated in various powder mixtures (Ti + B, Al + Fe{sub 2}O{sub 3}, Mo + B, etc.). It is shown that the reactions of high-temperature synthesis last for up to 0.1 s and are accompanied by the evaporation of powder grains and the formation of an aerosol cloud due to free expansion of reactants from the sample surface. The possibility of experimentally studying the kinetics of reactions of high-temperature synthesis is demonstrated. It is noticed that microwave discharges can be used to initiate plasmachemical reactions on the surfaces of radioparent materials in active gaseous media.

  13. River Flow Regimes and Effective Discharge

    NASA Astrophysics Data System (ADS)

    Basso, S.; Sprocati, R.; Frascati, A.; Marani, M.; Schirmer, M.; Botter, G.

    2015-12-01

    The concept of effective discharge is widespread in geomorphology and river engineering and restoration. For example, it is used to design the most stable channel configuration, to estimate sedimentation rate and lifespan of reservoirs and to characterize the hydrologic forcing in models studying long-term evolution of rivers. Accordingly, the effective discharge has been the focus of countless empirical, theoretical and numerical studies, which found it to vary among catchments as a function of climate, landscape and river morphology, type of transport (dissolved, suspended or bedload), and of streamflow variability. The heterogeneity of the effective discharge values observed in different catchments challenges a thorough understanding of its pivotal drivers, and a consistent framework which explains observations carried out in different geographic areas is still lacking. In the present work, the observed diversity is explained in terms of the underlying heterogeneity of river flow regimes, by linking effective discharge to attributes of the sediment rating curve and to streamflow variability, as resulting from climatic and landscape drivers. An analytic expression of the effective ratio (i.e. the ratio between effective discharge and mean streamflow) is provided, which captures observed values of effective discharge for suspended sediment transport in a set of catchments of the continental United States. The framework disentangles hydrologic and landscape controls on effective discharge, and highlights distinct effective ratios of persistent and erratic hydrologic regimes (respectively characterized by low and high flow variability), attributable to intrinsically different streamflow dynamics. Clusters of river catchments characterized by similar streamflow dynamics can be identified. The framework provides an opportunity for first-order estimates of effective discharge in rivers belonging to different areas, based on the type of flow regime.

  14. Powder evolution at low powers in silane-argon discharge

    SciTech Connect

    Chaudhuri, P.; Gupta, N. Dutta; Bhaduri, A.; Longeaud, C.; Vignoli, S.; Marty, O.

    2005-08-15

    Powder formation in a 13.56-MHz radio frequency (rf) capacitive glow discharge plasma of silane-argon mixture has been studied by in situ laser light-scattering measurements. The rf power density (P{sub rf}) was varied from 18 to 53 mW/cm{sup 2}. At high P{sub rf} the light scattering occurs all along the discharge and extends even beyond the exit end of the electrodes toward the pumping system. With decreasing P{sub rf} the maximum intensity of the light scattering decreases and the scattering zone shrinks and moves toward the exit end. With P{sub rf}{approx_equal}20 mW/cm{sup 2} a very bright scattering zone only a few centimeters wide appears located at the electrodes outlet. The powders studied by transmission electron microscopy did not show a drastic decrease of their sizes with P{sub rf} though clear coagulation of small particles is observed at high P{sub rf}. In this paper we have tried to link the laser light-scattering evolution with P{sub rf} to various parameters such as the microstructure factor, the deposition rate, the electron mobilityxlifetime product, the density of states, and the minority-carriers diffusion length of the films in an attempt to link the effect the evolution of powder formation to the films properties.

  15. Hydrogeologic data from the northern Powder River Basin, southeastern Montana

    USGS Publications Warehouse

    Slagle, Steven E.; Stimson, James R.

    1979-01-01

    Hydrologic and geologic data have been collected as part of energy-related projects conducted by the U.S. Geological Survey in the northern Powder River basin of southeastern Montana. Records of 1924 stock, domestic, irrigation, public supply and test wells are tabulated in the report. The data include well location, depth of well, casing diameter, type of lift, type of power, use of water, principal aquifer, altitude of land surface , water level, discharge, field specific conductance, and water temperature. Locations of the inventoried wells are shown on a map at a scale of 1:500,000. Lighologic logs of 373 wells and test holes are also included. The geologic units considered range in age from Late Cretaceous to Holocene. (Kosco-USGS)

  16. Amazon River discharge estimated from TOPEX/Poseidon altimetry

    NASA Astrophysics Data System (ADS)

    Zakharova, Elena A.; Kouraev, Alexei V.; Cazenave, Anny; Seyler, Frédérique

    2006-02-01

    This paper presents an application of the TOPEX/Poseidon (T/P) satellite altimetry data to estimate river discharge at three sites along the Amazon River. We discuss the methodology to establish empirical relationships between satellite-derived water levels and daily estimations of river discharges based on rating curves and in situ level measurements at gauging stations. Three sites are chosen: Manacapuru (River Solimões), Jatuarana (nearby the confluence of the Solimões and Rio Negro rivers) and Óbidos (Amazon River). We then reconstruct the satellite-based river discharge over a 10-year time span (1992-2002). Comparison between satellite-derived and river discharge at the gauging stations shows that the T/P data can successfully be used for hydrological studies of large rivers, in providing in particular discharge estimates when in situ data are not available. To cite this article: E.A. Zakharova et al., C. R. Geoscience 338 (2006).

  17. Coalbed Methane Extraction and Soil Suitability Concerns in the Powder River Basin, Montana and Wyoming

    USGS Publications Warehouse

    ,

    2006-01-01

    The Powder River Basin is located in northeastern Wyoming and southeastern Montana. It is an area of approximately 55,000 square kilometers. Extraction of methane gas from the coal seams that underlie the Powder River Basin began in Wyoming in the late 1980s and in Montana in the late 1990s. About 100-200 barrels of co-produced water per day are being extracted from each active well in the Powder River Basin, which comes to over 1.5 million barrels of water per day for all the active coalbed methane wells in the Basin. Lab testing indicates that Powder River Basin co-produced water is potable but is high in sodium and other salts, especially in the western and northern parts of the Powder River Basin. Common water management strategies include discharge of co-produced water into drainages, stock ponds, evaporation ponds, or infiltration ponds; treatment to remove sodium; or application of the water directly on the land surface via irrigation equipment or atomizers. Problems may arise because much of the Powder River Basin contains soils with high amounts of swelling clays. As part of the USGS Rocky Mountain Geographic Science Center's hyperspectral research program, researchers are investigating whether hyperspectral remote sensing data can be beneficial in locating areas of swelling clays. Using detailed hyperspectral data collected over parts of the Powder River Basin and applying our knowledge of how the clays of interest reflect energy, we will attempt to identify and map areas of swelling clays. If successful, such information will be useful to resource and land managers.

  18. 61. VIEW OF SALT RIVER PROJECT WELL DISCHARGING WATER INTO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    61. VIEW OF SALT RIVER PROJECT WELL DISCHARGING WATER INTO THE ARIZONA CANAL NEAR 47TH AVENUE, LOOKING SOUTH Photographer: James Eastwood, July 1990 - Arizona Canal, North of Salt River, Phoenix, Maricopa County, AZ

  19. Electro-Static Discharge (ESD) Sensitivity of Reactive Powders and its Mitigation

    DTIC Science & Technology

    2016-03-16

    ADDRESS. New Jersey Institute of Technology University Heights Newark, NJ 07102 -1982 ABSTRACT Final Report: Electro-Static Discharge (ESD) Sensitivity of...Static Discharge Ignition of Monolayers of Nanocomposite Thermite Powders Prepared by Arrested Reactive Milling, Combustion Science and Technology ...Schoenitz, Edward L. Dreizin. Validation of the Thermal Oxidation Model for Al/CuO Nanocomposite Powder, Combustion Science and Technology , (01

  20. Coal stratigraphy of northern and central Powder River basin

    SciTech Connect

    McLellan, M.W.; Biewick, L.H.; Molina, C.L.; Pierce, F.W.

    1986-08-01

    Reconstructed stratigraphic frameworks contribute to understanding depositional and structural history of Paleocene rocks in the Powder River basin. By correlating Fort Union Formation coal beds from Foster Creek, Montana, 100 mi southward to near Gillette, Wyoming, they reconstructed the framework from Terret up through Anderson coal beds, about 1700 ft of stratigraphic section. This framework comprises intersecting stratigraphic sections showing distribution of thick coal beds and sandstones across the study area. Coal beds from Terret up through Knobloch are thickest in northern Powder River basin. Stratigraphically above in the Cache through Wall section, the coal beds are thickest farther south in Moorhead and northern Spotted Horse coalfields. Otter through Anderson coal beds are thickest still farther south in central Powder River basin. Principal coal beds had been mapped in individual local coal fields and identified by local names. They have correlated the coal beds and connected these stratigraphic sections (framework) with stratigraphic frameworks from the southern Powder River basin to provide an integrated picture of coal deposition. Large coal swamps existed in Fort Union time, first in northern Powder River basin and successively farther southward. Basin margins were tectonically active during the Paleocene. Clastic sedimentation resulting from this tectonism may have created conditions controlling peat deposition. Intermittently, peat deposition was interrupted across large areas by a great influx of clastic sediments. At other times, peat deposits were cut by narrow channels as drainage systems changed course.

  1. Monitoring river discharge with remotely sensed imagery using river island area as an indicator

    NASA Astrophysics Data System (ADS)

    Ling, Feng; Cai, Xiaobin; Li, Wenbo; Xiao, Fei; Li, Xiaodong; Du, Yun

    2012-01-01

    River discharge is an important parameter in understanding water cycles, and consistent long-term discharge records are necessary for related research. In practice, discharge records based on in situ measurement are often limited because of technological, economic, and institutional obstacles. Satellite remote sensing provides an attractive alternative way to measure river discharge by constructing an empirical rating curve between the parameter provided by remote sensing techniques and simultaneous ground discharge data. River width is a popular parameter for constructing the empirical curve, since change in river discharge can be represented by a change in river width. In some rectangular channels, however, river width does not change significantly with river discharge, so an alternative parameter is necessary. We analyze a novel technique using river island area as an indicator of discharge. A river island often has a flat terrain, and its area decreases with higher discharge. This technique is validated by three river islands in the Yangtze River in China. All 61 remotely sensed images acquired by the HuanJing (HJ) satellites from 2009 to 2010 were correlated with corresponding in situ discharge of the nearby Zhicheng hydrological station. The performance of fitted curves for inferring river discharge is validated using 36 HJ images taken in 2011, and the influence of remotely sensed imagery and river islands is discussed. All three river islands can be used as indicators of river discharge, although their performances are much different. For the river island with the best result, the mean accuracy of the estimates is less than 10% of the observed discharge, and all relative errors are within 20%, validating the effectiveness of the proposed method.

  2. Characteristics of sediment discharge in the subarctic Yukon River, Alaska

    USGS Publications Warehouse

    Chikita, K.A.; Kemnitz, R.; Kumai, R.

    2002-01-01

    The characteristics of sediment discharge in the Yukon River, Alaska were investigated by monitoring water discharge, water turbidity and water temperature. The river-transported sediment, 90 wt.% or more, consists of silt and clay (grain size ??? 62.5 ??m), which probably originated in the glacier-covered mountains mostly in the Alaska Range. For early June to late August 1999, we continuously measured water turbidity and temperature near the estuary and in the middle of Yukon River by using self-recording turbidimeters and temperature data loggers. The water turbidity (ppm) was converted to suspended sediment concentration (SSC; mg/l) of river water, using a relation between simultaneous turbidity and SSC at each of the two sites, and then, the suspended sediment discharge, approximately equal to water discharge times SSC, was numerically obtained every 1 or 2 h. It should be noted that the sediment discharge in the Yukon River is controlled by SSC rather than water discharge. As a result, a peak sediment discharge occurred in mid or late August by local sediment runoffs due to glacier-melt (or glacier-melt plus rainfall), while a peak water discharge was produced by snowmelt in late June or early July. Application of the "extended Shields diagram" indicates that almost all the river-transported sediments are under complete suspension. ?? 2002 Elsevier Science B.V. All rights reserved.

  3. Estimating river discharge rates through remotely sensed thermal plumes

    NASA Astrophysics Data System (ADS)

    Abou Najm, M.; Alameddine, I.; Ibrahim, E.; Nasr, R.

    2016-12-01

    An empirical relationship is developed for estimating river discharge rates from remotely sensed thermal plumes that generate due to the temperature gradient at the interface between rivers and large water bodies. The method first determines the plumes' near field area, length scale, and length scale deviation angle from river channel centerline from Landsat 7 ETM+ satellite images. It also makes use of mean river and ocean temperatures and tidal levels collected from NOAA. A multiple linear regression model is then used to predict measured daily discharge rates with the determined predictors. The approach is tested and validated with discharge rates collected from four USGS gauged rivers in Oregon and California. Results from 116 Landsat 7 ETM+ satellites images of the four rivers show that the standard error of the discharge estimates were within a factor of 1.5-2.0 of observed values, with mean estimate accuracy of 10%. Goodness of fit (R2) ranged from 0.51 for the Rogue River up to 0.64 for the Coquille and Siuslaw rivers. The method offers an opportunity to monitor changes in flow discharge in ungauged basins, where tidal flow is not dominating and where a temperature difference of 2 oC exists between the river and the receiving water body.

  4. Geothermal resources of the Southern Powder River Basin, Wyoming

    SciTech Connect

    Heasler, H.P.; Buelow, K.L.; Hinckley, B.S.

    1985-06-13

    This report describes the geothermal resources of the Southern Powder River Basin. The report contains a discussion of the hydrology as it relates to the movement of heated water, a description and interpretation of the thermal regime, and four maps: a generalized geological map, a structure contour map, a thermal gradient contour map, and a ground water temperature map. 10 figs. (ACR)

  5. 76 FR 58533 - Powder River Regional Coal Team Activities; Notice of Public Meeting in Casper, WY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

    ... management activities in the Powder River Coal Production Region. DATES: The RCT meeting will begin at 9 a.m... Powder River Coal Production Region as well as other Federal coal- related actions in the region... existing coal LBAs in the Powder River Coal Production Region. 2. Update on U.S. Geological Survey coal...

  6. Experimental study of the polymer powder film thickness uniformity produced by the corona discharge

    NASA Astrophysics Data System (ADS)

    Fazlyyyakhmatov, Marsel

    2017-01-01

    The results of an experimental study of the polymer powder film thickness uniformity are presented. Polymer powder films are produced by the electrostatic field of corona discharge. Epoxy and epoxy-polyester powder films with thickness in the range of 30-120 microns are studied. Experimentally confirmed possibility of using these coatings as protective matching layer of piezoceramic transducers at frequencies of 0.5-15 MHz.

  7. River discharge measurements by using helicopter-mounted radar

    USGS Publications Warehouse

    Melcher, N.B.; Costa, J.E.; Haeni, F.P.; Cheng, R.T.; Thurman, E.M.; Buursink, M.; Spicer, K.R.; Hayes, E.; Plant, W.J.; Keller, W.C.; Hayes, K.

    2002-01-01

    The United States Geological Survey and the University of Washington collaborated on a series of initial experiments on the Lewis, Toutle, and Cowlitz Rivers during September 2000 and a detailed experiment on the Cowlitz River during May 2001 to determine the feasibility of using helicopter-mounted radar to measure river discharge. Surface velocities were measured using a pulsed Doppler radar, and river depth was measured using ground-penetrating radar. Surface velocities were converted to mean velocities, and horizontal registration of both velocity and depth measurements enabled the calculation of river discharge. The magnitude of the uncertainty in velocity and depth indicate that the method error is in the range of 5 percent. The results of this experiment indicate that helicopter-mounted radar can make the rapid, accurate discharge measurements that are needed in remote locations and during regional floods.

  8. Improving machining performance using alumina powder-added dielectric during electrical discharge machining (EDM)

    NASA Astrophysics Data System (ADS)

    Khan, Ahsan Ali; Abu Bakar, Marina Binti; Hazza Faizi Al-Hazza, Muataz; Radzi Haji Che Daud, Mohd; Mohiuddin, AKM

    2017-03-01

    Alumina powder was added to dielectric fluid during Electrical discharge machining (EDM) of AISI 304 steel. The main machining parameters of current (A), tool diameter (mm) and powder concentration (g/L) were chosen to determine the EDM machining characteristics of material removal rate (MRR), tool wear rate (TWR) and surface roughness (Ra). This work adopted two-level full factorial experiments. The significant factors that affect the MRR and tool TWR are current, tool diameter and powder concentration. The MRR increases when the current and tool diameter are higher. The presence of powder concentration also increases the MRR. The higher current used and the presence of powder concentration increase the TWR. Meanwhile, a smaller tool diameter gives higher value of TWR. Current and powder concentration are the significant factors to determine the surface roughness of work surfaces. Higher current applied gives high surface roughness, but higher powder concentration gives improved surface finish.

  9. Effective Discharge and Annual Sediment Yield on Brazos River

    NASA Astrophysics Data System (ADS)

    Rouhnia, M.; Salehi, M.; Keyvani, A.; Ma, F.; Strom, K. B.; Raphelt, N.

    2012-12-01

    Geometry of an alluvial river alters dynamically over the time due to the sediment mobilization on the banks and bottom of the river channel in various flow rates. Many researchers tried to define a single representative discharge for these morphological processes such as "bank-full discharge", "effective discharge" and "channel forming discharge". Effective discharge is the flow rate in which, the most sediment load is being carried by water, in a long term period. This project is aimed to develop effective discharge estimates for six gaging stations along the Brazos River from Waco, TX to Rosharon, TX. The project was performed with cooperation of the In-stream Flow Team of the Texas Water Development Board (TWDB). Project objectives are listed as: 1) developing "Flow Duration Curves" for six stations based on mean-daily discharge by downloading the required, additional data from U.S Geological Survey website, 2) developing "Rating Curves" for six gaging stations after sampling and field measurements in three different flow conditions, 3) developing a smooth shaped "Sediment Yield Histogram" with a well distinguished peak as effective discharge. The effective discharge was calculated using two methods of manually and automatic bin selection. The automatic method is based on kernel density approximation. Cross-sectional geometry measurements, particle size distributions and water field samples were processed in the laboratory to obtain the suspended sediment concentration associated with flow rate. Rating curves showed acceptable trends, as the greater flow rate we experienced, the more sediment were carried by water.

  10. Exploring SWOT discharge algorithm accuracy on the Sacramento River

    NASA Astrophysics Data System (ADS)

    Durand, M. T.; Yoon, Y.; Rodriguez, E.; Minear, J. T.; Andreadis, K.; Pavelsky, T. M.; Alsdorf, D. E.; Smith, L. C.; Bales, J. D.

    2012-12-01

    Scheduled for launch in 2019, the Surface Water and Ocean Topography (SWOT) satellite mission will utilize a Ka-band radar interferometer to measure river heights, widths, and slopes, globally, as well as characterize storage change in lakes and ocean surface dynamics with a spatial resolution ranging from 10 - 70 m, with temporal revisits on the order of a week. A discharge algorithm has been formulated to solve the inverse problem of characterizing river bathymetry and the roughness coefficient from SWOT observations. The algorithm uses a Bayesian Markov Chain estimation approach, treats rivers as sets of interconnected reaches (typically 5 km - 10 km in length), and produces best estimates of river bathymetry, roughness coefficient, and discharge, given SWOT observables. AirSWOT (the airborne version of SWOT) consists of a radar interferometer similar to SWOT, but mounted aboard an aircraft. AirSWOT spatial resolution will range from 1 - 35 m. In early 2013, AirSWOT will perform several flights over the Sacramento River, capturing river height, width, and slope at several different flow conditions. The Sacramento River presents an excellent target given that the river includes some stretches heavily affected by management (diversions, bypasses, etc.). AirSWOT measurements will be used to validate SWOT observation performance, but are also a unique opportunity for testing and demonstrating the capabilities and limitations of the discharge algorithm. This study uses HEC-RAS simulations of the Sacramento River to first, characterize expected discharge algorithm accuracy on the Sacramento River, and second to explore the required AirSWOT measurements needed to perform a successful inverse with the discharge algorithm. We focus on several specific research questions affecting algorithm performance: 1) To what extent do lateral inflows confound algorithm performance? We examine the ~100 km stretch of river from Colusa, CA to the Yolo Bypass, and investigate how the

  11. Market analysis for Powder River inconclusive on leasing needs

    SciTech Connect

    Not Available

    1987-03-01

    To assist the Regional Coal Team (RCT) in deciding on a recommended leasing level for the region, the Bureau of Land Management (BLM) has assessed the demand for Powder River coal reserves through the year 2000. This market analysis is to be used as one input into the RCT decision. The regional market analysis does not evaluate individual coal tracts. It utilizes broad indicators of market demand to identify tonnage ranges that would satisfy various objectives. The analysis consists of six methodologies that address various objectives of the coal program. The six methodologies are: minimum leasing, past sales, contracting rate, strategic supply, production needs, and expressions of interest. A wide range results from the six methodologies used to identify various leasing options for the Powder River Region. It will be up to the RCT to decide how to make use of this analysis.

  12. River discharge estimation at daily resolution from satellite altimetry over an entire river basin

    NASA Astrophysics Data System (ADS)

    Tourian, M. J.; Schwatke, C.; Sneeuw, N.

    2017-03-01

    One of the main challenges of hydrological modeling is the poor spatiotemporal coverage of in situ discharge databases which have steadily been declining over the past few decades. It has been demonstrated that water heights over rivers from satellite altimetry can sensibly be used to deal with the growing lack of in situ discharge data. However, the altimetric discharge is often estimated from a single virtual station suffering from coarse temporal resolution, sometimes with data outages, poor modeling and inconsistent sampling. In this study, we propose a method to estimate daily river discharge using altimetric time series of an entire river basin including its tributaries. Here, we implement a linear dynamic model to (1) provide a scheme for data assimilation of multiple altimetric discharge along a river; (2) estimate daily discharge; (3) deal with data outages, and (4) smooth the estimated discharge. The model consists of a stochastic process model that benefits from the cyclostationary behavior of discharge. Our process model comprises the covariance and cross-covariance information of river discharge at different gauges. Combined with altimetric discharge time series, we solve the linear dynamic system using the Kalman filter and smoother providing unbiased discharge with minimum variance. We evaluate our method over the Niger basin, where we generate altimetric discharge using water level time series derived from missions ENVISAT, SARAL/AltiKa, and Jason-2. Validation against in situ discharge shows that our method provides daily river discharge with an average correlation of 0.95, relative RMS error of 12%, relative bias of 10% and NSE coefficient of 0.7. Using a modified NSE-metric, that assesses the non-cyclostationary behavior, we show that our estimated discharge outperforms available legacy mean daily discharge.

  13. Sediment discharge in the Colorado River near De Beque, Colorado

    USGS Publications Warehouse

    Butler, D.L.

    1986-01-01

    A study was conducted to determine annual-sediment discharge at the site of a proposed reservoir on the Colorado River at Una, located 3 miles upstream from De Beque, Colorado. Eleven suspended sediment samples were collected during 1984 at the De Beque bridge. These data were combined with suspended sediment data collected for the Colorado River at two nearby streamflow gaging stations to define relations between suspended-sediment discharge and stream discharge. Best results were obtained when the data were separated into two periods, March through October, and November through February. The data for March through October were separated into two periods: (1) Rising stream-stage period, which includes data collected prior to the data of the annual peak-stream discharge, and (2) falling stream-stage period, which includes data collected after the date of the annual peak-stream discharge. Nine bedload samples were collected during 1984 to determine the contribution of bedload sediment discharge to total sediment discharge. Bedload accounted for < 2% of total sediment discharge. The best relations describing bedload sediment discharge were obtained when the bedload data were separated into two periods: (1) Data collected prior to the date of the annual peak-stream discharge, and (2) data collected after the date of the annual peak-stream discharge. Mean annual sediment discharge in the Colorado River at the proposed Una reservoir site was estimated to be 1,065,000 tons/year for October 1966 through September 1984. Water storage capacity of the proposed reservoir would decrease about 30% after 100 years at this sediment discharge rate. (USGS)

  14. Estimating discharge in rivers using remotely sensed hydraulic information

    USGS Publications Warehouse

    Bjerklie, D.M.; Moller, D.; Smith, L.C.; Dingman, S.L.

    2005-01-01

    A methodology to estimate in-bank river discharge exclusively from remotely sensed hydraulic data is developed. Water-surface width and maximum channel width measured from 26 aerial and digital orthophotos of 17 single channel rivers and 41 SAR images of three braided rivers were coupled with channel slope data obtained from topographic maps to estimate the discharge. The standard error of the discharge estimates were within a factor of 1.5-2 (50-100%) of the observed, with the mean estimate accuracy within 10%. This level of accuracy was achieved using calibration functions developed from observed discharge. The calibration functions use reach specific geomorphic variables, the maximum channel width and the channel slope, to predict a correction factor. The calibration functions are related to channel type. Surface velocity and width information, obtained from a single C-band image obtained by the Jet Propulsion Laboratory's (JPL's) AirSAR was also used to estimate discharge for a reach of the Missouri River. Without using a calibration function, the estimate accuracy was +72% of the observed discharge, which is within the expected range of uncertainty for the method. However, using the observed velocity to calibrate the initial estimate improved the estimate accuracy to within +10% of the observed. Remotely sensed discharge estimates with accuracies reported in this paper could be useful for regional or continental scale hydrologic studies, or in regions where ground-based data is lacking. ?? 2004 Elsevier B.V. All rights reserved.

  15. Recent trends and variability in river discharge across northern Canada

    NASA Astrophysics Data System (ADS)

    Déry, Stephen J.; Stadnyk, Tricia A.; MacDonald, Matthew K.; Gauli-Sharma, Bunu

    2016-12-01

    This study presents an analysis of the observed inter-annual variability and inter-decadal trends in river discharge across northern Canada for 1964-2013. The 42 rivers chosen for this study span a combined gauged area of 5.26 × 106 km2 and are selected based on data availability and quality, gauged area and record length. Inter-annual variability in river discharge is greatest for the eastern Arctic Ocean (coefficient of variation, CV = 16 %) due to the Caniapiscau River diversion into the La Grande Rivière system for enhanced hydropower production. Variability is lowest for the study area as a whole (CV = 7 %). Based on the Mann-Kendall test (MKT), no significant (p > 0.05) trend in annual discharge from 1964 to 2013 is observed in the Bering Sea, western Arctic Ocean, western Hudson and James Bay, and Labrador Sea; for northern Canada as a whole, however, a statistically significant (p < 0.05) decline of 102.8 km3 25 yr-1 in discharge occurs over the first half of the study period followed by a statistically significant (p < 0.05) increase of 208.8 km3 25 yr-1 in the latter half. Increasing (decreasing) trends in river discharge to the eastern Hudson and James Bay (eastern Arctic Ocean) are largely explained by the Caniapiscau diversion to the La Grande Rivière system. Strong regional variations in seasonal trends of river discharge are observed, with overall winter (summer) flows increasing (decreasing, with the exception of the most recent decade) partly due to flow regulation and storage for enhanced hydropower production along the Hudson and James Bay, the eastern Arctic Ocean and Labrador Sea. Flow regulation also suppresses the natural variability of river discharge, particularly during cold seasons.

  16. Arctic River Discharge and Sediment Loads --- an Overview

    NASA Astrophysics Data System (ADS)

    Syvitski, J. P.; Overeem, I.; Brakenridge, G. R.; Hudson, B.; Cohen, S.

    2014-12-01

    Evidence suggests that river discharge has been increasing (+10%) over the last 30 years (1977-2007) for most arctic rivers. The peak melt month occurs earlier in the season in 66% of the studied rivers. Cold season flow is also increasing. Satellite discharge estimates, daily, based on microwave radiometry, are now possible from 1998 onwards. Daily river discharge hindcasts over the last 60 years using the water balance model WBMsed at a 10km spatial resolution are now available. The WBMsed model can be used in forecast mode assuming valid input climatology. The challenge here has been the accuracy of sub-polar precipitation grids. While each of these three methods (gauging, orbital sensing, modeling) has temporal and spatial coverage limitations, the combination of all three methods provides for a realistic way forward for estimating local discharge across the pan arctic. Flood inundation products are routinely produced for the pan-arctic using automated mapping algorithms developed by the Dartmouth Flood Observatory. The determination of artic river sediment loads is less than ideal. Some rivers have only been monitored for a short number of years, and many have not been monitored at all. The WBMsed model is perhaps the best method of estimating the daily sediment flux to the Arctic Ocean, at least for rivers where the mean discharge is greater than 30 m3/s. Additionally there is limited-duration field monitoring by national surveys. New methods are being explored, including back calculating the delivery of sediment to the coastal ocean by plume dimensions observed from space (MODIS, LandSat). These methods have had moderate success when applied to plumes extending in the Greenland fjords. Canada maintains an active circa 7-y satellite program (ArcticNet) to track the Mackenzie discharge during the spring-summer runoff period when turbid river water is apt to flow under and over marginal sea ice in the Beaufort Sea.

  17. Research of the possibility of using an electrical discharge machining metal powder in selective laser melting

    NASA Astrophysics Data System (ADS)

    Golubeva, A. A.; Sotov, A. V.; Agapovichev, A. V.; Smelov, V. G.; Dmitriev, V. N.

    2017-02-01

    In this paper the research of a Ni-20Cr-10Fe-3Ti (heat-resistant) alloy metal powder conducted for use in a selective laser melting technology. This metal powder is the slime after electric discharge machining. The technology of cleaning and melting the powder discussed in this article. As a control input of the powder, immediately before 3D printing, dimensional analysis, surface morphology and the internal structure of the powder particles after the treatment were examined using optical and electron microscopes. The powder granules are round, oval, of different diameters with non-metallic inclusions. The internal structure of the particles is solid with no apparent defects. The content of the required diameter of the total volume of test powder granules was 15%. X-ray fluorescence analysis of the powder materials carried out. The possibility of powder melting was investigated in the selective laser melting machine ‘SLM 280HL’. A selection of the melting modes based on the physical properties of the Ni-20Cr-10Fe-3Ti alloy, data obtained from similar studies and a mathematical model of the process. Conclusions on the further investigation of the possibility of using electric discharge machining slime were made.

  18. Using MODIS data to estimate river discharge in ungauged sites

    NASA Astrophysics Data System (ADS)

    Tarpanelli, A.; Brocca, L.; Lacava, T.; Faruolo, M.; Melone, F.; Moramarco, T.; Pergola, N.; Tramutoli, V.

    2012-04-01

    The discharge prediction at a river site is fundamental for water resources management and flood risk prevention. An accurate discharge estimation depends on local hydraulic conditions which are usually detected by recording water level and carrying out flow measurements, which are costly and sometimes impractical for high flows. Over the last decade, the possibility to obtain river discharge estimates from satellite sensors data has become of considerable interest. For large river basins, the use of satellite data derived by altimeter and microwave sensors, characterized by a daily temporal resolution, has proven to be a useful tool to integrate or even increase the discharge monitoring. For smaller basins, Synthetic Aperture Radars (SARs) have been usually employed for the indirect estimation of water elevation but their low temporal resolution (from a few days up to 30 days) might be considered not suitable for discharge prediction. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard of Terra and Aqua Earth Observing System (EOS) satellites, can provide a proper tradeoff between temporal and spatial resolution useful for discharge estimation. It assures, in fact, at least a daily temporal resolution and a spatial resolution up to 250 m in the first two channels. In this study, the capability of MODIS data for discharge prediction is investigated. Specifically, the different spectral behavior of water and land in the Near Infrared (NIR) portion of the electromagnetic spectrum (MODIS channel 2) is exploited by computing the ratio of the MODIS channel 2 reflectance values between two pixels located within and outside the river. Values of such a ratio should increase when more water and, hence, discharge, is present. Time series of daily water level, velocity and discharge between 2002 and 2010 measured at different gauging stations located along the Upper Tiber River (central Italy) and the Po River (North Italy), as well as MODIS channel 2 data for

  19. Climatic variability between SST and river discharge at Amazon region

    NASA Astrophysics Data System (ADS)

    Silva, M. E.; Silva, E. R. L.

    2012-04-01

    Climatic variability, related both to precipitation and river discharge, has been associated to ocean variability. Authors commonly relate Pacific sea surface temperature (SST) variation to South America (SA) precipitation. Zonal displacement of Walker cell, with intensified subsidence over northern portion of SA, Subtropical Jet strengthening/weakening over extratropical latitudes of SA are, respectively, dynamical reasons scientifically accepted for increasing and depletion of precipitation at the respective areas. Many studies point out the influence of tropical Atlantic SST anomalies in relation to precipitation/river discharge variability over northeast of Brazil. Aliseos variability at tropical Atlantic is also a physic process that contributes to explain precipitation and river flow variability over SA, mainly over the north portion. In this study, we aim to investigate the temporal correlation between SST, mainly from Pacific and Atlantic oceans, and rivers discharge at the Amazon region. Ji-Parana, Madeira and Tapajós river discharge in monthly and annual scale, between 1968 and 2008, were the time series selected to reach the purpose. Time series for river discharge were obtained from Agência Nacional de Águas (ANA, in Portuguese) and, SST data were obtained from CDC/NOAA. Before linear correlation computations between river discharge and SST have been made, seasonal cycle and linear tendency were removed from all original time series. Areas better correlated to river discharge at Amazon region show oceanic patterns apparently associated to PDO (Pacific Decadal Oscillation) and ENSO (El Niño-South Oscillation) variability, with absolute values greater than 0.3 and reaching 0.5 or 0.6. The spatial pattern observed at Pacific basin is similar to that showed by the first mode of PCA (Principal Component Analysis), such seen in many studies (the "horse shoe" pattern). In general, negative correlation values appear far more to the west of Pacific basin

  20. River Discharge Estimation Using Imaged Critical Flow Phenomena

    NASA Astrophysics Data System (ADS)

    Fonstad, M. A.; Grant, G.

    2015-12-01

    A wide variety of river science applications require remote estimation of discharge. Flow in steep rivers often approach critical flow (Froude number equal to one), as evidenced by trains of standing waves either perpendicular or at a high angle relative to the flow direction. Previous work has demonstrated that where such waves are present, water depth can be estimated without the need for a roughness coefficient such as Manning's n. We extend this prior work to remotely calculate river discharge. The wavelength of standing waves can be measured using high-resolution remote sensing imagery. Velocity can then be calculated from wavelength using the Kennedy wave equation. Assuming critical flow allows depth to be calculated using the modified Froude number equation, and with an additional measurement of imaged river width, river discharge can be computed directly as the product of these three values. We test this approach using high-resolution Google Earth imagery of rivers with standing waves near existing stream gages. We also demonstrate the utility of this approach by extracting a drainage area-to-discharge relationship for a large watershed. There are certain challenges with this approach, the greatest being the need for high resolution (meter-scale or better) imagery to see and measure standing waves. Such waves are also easily confused with wind waves, turbulence or other surface effects. Nevertheless, this approach offers promise for both estimating discharge in places without extensive gage networks, and also estimating discharge in archival imagery. Repeat imaging of the same areas might also be used to construct at-a-station and downstream hydraulic geometry relationships.

  1. Assessing the potential global extent of SWOT river discharge observations

    NASA Astrophysics Data System (ADS)

    Pavelsky, Tamlin M.; Durand, Michael T.; Andreadis, Konstantinos M.; Beighley, R. Edward; Paiva, Rodrigo C. D.; Allen, George H.; Miller, Zachary F.

    2014-11-01

    Despite its importance as a major element of the global hydrologic cycle, runoff remains poorly constrained except at the largest spatial scales due to limitations of the global stream gauge network and inadequate data sharing. Efforts using remote sensing to infer runoff from discharge estimates are limited by characteristics of present-day sensors. The proposed Surface Water and Ocean Topography (SWOT) mission, a joint project between the United States and France, aims to substantially improve space-based estimates of river discharge. However, the extent of rivers observable by SWOT, likely limited to those wider than 50-100 m, remains unknown. Here, we estimate the extent of SWOT river observability globally using a downstream hydraulic geometry (DHG) approach combining basin areas from the Hydro1k and Hydrosheds elevation products, discharge from the Global Runoff Data Centre (GRDC), and width estimates from a global width-discharge relationship. We do not explicitly consider SWOT-specific errors associated with layover and other phenomena in this analysis, although they have been considered in formulation of the 50-100 m width thresholds. We compare the extent of SWOT-observable rivers with GRDC and USGS gauge datasets, the most complete datasets freely available to the global scientific community. In the continental US, SWOT would match USGS river basin coverage only at large scales (>25,000 km2). Globally, SWOT would substantially improve on GRDC observation extent: SWOT observation of 100 m (50 m) rivers will allow discharge estimation in >60% of 50,000 km2 (10,000 km2) river basins. In contrast, the GRDC observes fewer than 30% (15%) of these basins. SWOT could improve characterization of global runoff processes, especially with a 50 m observability threshold, but in situ gauge data remains essential and must be shared more freely with the international scientific community.

  2. Developing new algorithms for estimating river discharge from SWOT

    NASA Astrophysics Data System (ADS)

    Pavelsky, T. M.; Durand, M. T.

    2012-12-01

    Flow of water through rivers is a critical component of the global hydrologic cycle, yet discharge on many of the world's rivers remains poorly constrained by ground-based observations. The planned NASA/CNES Surface Water and Ocean Topography (SWOT) satellite mission will provide concurrent observations of inundated area, water surface elevation, and its spatial derivative (surface slope) for rivers wider than 100 m (and perhaps as narrow as 50 m), which will allow a step-change improvement in our ability to characterize river discharge from space. New discharge algorithms must be developed to incorporate SWOT's unprecedented observations. While ground-based discharge is usually measured at river cross-sections, SWOT will estimate discharge over river reaches of variable length. Cross-sectional discharge is often estimated using slope-area scaling methods such as Manning's Equation, and modified forms of these equations could be used to estimate reach-averaged discharge. While some of the parameters required to estimate discharge are measured directly by SWOT, others including baseflow depth and channel roughness (e.g. Manning's n) are not. Promising new methods are under development to estimate baseflow depth in selected river reaches by extrapolating width-stage relationships. In contrast, channel roughness has received relatively little attention. By combining SWOT observations of several reaches over multiple overpasses, however, it may be possible to simultaneously derive both depth and channel roughness from SWOT observations alone. The principle in this method is to start from mass and momentum conservation, apply a slope-area method such as Manning's equation, assume the roughness coefficient and bathymetry are temporally-invariant, then solve for the unknowns by constraining over a number of overpasses. In principle, only four overpasses are needed for this method, but in practice more will likely be needed to obtain an accurate solution; the actual number

  3. Towards remote sensing of river discharge from space (Invited)

    NASA Astrophysics Data System (ADS)

    Smith, L. C.; Durand, M. T.; Andreadis, K.; Mersel, M. K.

    2010-12-01

    Consistent, spatially extensive measurements of water flux in rivers are essential for numerous scientific and pragmatic reasons, but such data are absent for many parts of the world. Satellite retrievals of river discharge, therefore, are a tantalizing prospect and stated science requirement of at least one proposed satellite mission (SWOT, the Surface Water Ocean Topography mission). While remote sensing will never achieve the continuous temporal sampling of permanent in situ river gauging stations, the dense synoptic sampling afforded from space provides a powerful compliment to in situ networks with strong potential to transform the science of land-surface hydrology in much the same way that radar altimeters have transformed the science of physical oceanography since 1978. In many parts of the world, satellite retrievals offer the only hope for obtaining any discharge proxies at all. However, an outstanding problem is that no remote sensing technology can measure river discharge directly. A variety of approaches ranging from in situ calibration to advanced data-assimilation modeling have been explored, but the field is highly immature. This poses both challenges and opportunities for the hydrologic science community, as it progresses toward developing effective remote-sensing algorithms to obtain synoptic, intercalibrated, and consistent measurements of discharge throughout entire river drainage networks.

  4. Computations of total sediment discharge, Niobrara River near Cody, Nebraska

    USGS Publications Warehouse

    Colby, Bruce R.; Hembree, C.H.

    1955-01-01

    A natural chute in the Niobrara River near Cody, Nebr., constricts the flow of the river except at high stages to a narrow channel in which the turbulence is sufficient to suspend nearly the total sediment discharge. Because much of the flow originates in the sandhills area of Nebraska, the water discharge and sediment discharge are relatively uniform. Sediment discharges based on depth-integrated samples at a contracted section in the chute and on streamflow records at a recording gage about 1,900 feet upstream are available for the period from April 1948 to September 1953 but are not given directly as continuous records in this report. Sediment measurements have been made periodically near the gage and at other nearby relatively unconfined sections of the stream for comparison with measurements at the contracted section. Sediment discharge at these relatively unconfined sections was computed from formulas for comparison with measured sediment discharges at the contracted section. A form of the Du Boys formula gave computed tonnages of sediment that were unsatisfactory. Sediment discharges as computed from the Schoklitsch formula agreed well with measured sediment discharges that were low, but they were much too low at measured sediment discharges that were higher. The Straub formula gave computed discharges, presumably of bed material, that were several times larger than measured discharges of sediment coarser than 0.125 millimeter. All three of these formulas gave computed sediment discharges that increased with water discharges much less rapidly than the measured discharges of sediment coarser than 0.125 millimeter. The Einstein procedure when applied to a reach that included 10 defined cross sections gave much better agreement between computed sediment discharge and measured sediment discharge than did anyone of the three other formulas that were used. This procedure does not compute the discharge of sediment that is too small to be found in the stream bed in

  5. River discharge contribution to sea-level rise in the Yangtze River Estuary, China

    NASA Astrophysics Data System (ADS)

    Kuang, Cuiping; Chen, Wei; Gu, Jie; Su, Tsung-Chow; Song, Hongling; Ma, Yue; Dong, Zhichao

    2017-02-01

    Sea level changes in the Yangtze River Estuary (YRE) as a result of river discharge are investigated based on the monthly averaged river discharge from 1950 to 2011 at the Datong station. Quantification of the sea level contribution is made by model computed results and the sea level rates reported by the China Sea Level Bulletin (CSLB). The coastal modeling tool, MIKE21, is used to establish a depth-averaged hydrodynamic model covering the YRE and Hangzhou Bay. The model is validated with the measured data. Multi-year monthly river discharges are statistically calculated based on the monthly river discharges at Datong station from 1950 to 2011. The four characteristic discharges (frequency of 75%, 50% and 25%, and multi-year monthly) and month-averaged river discharge from 1950 to 2011 are used to study the seasonal and long-term changes of sea level. The computed sea level at the Dajishan and Lvsi stations are used to study the multi-time scale structure of periodic variation in different time scale of river discharge series. The results reveal that (1) the sea level rises as the river discharge increases, and its amplification decreases from upstream to the offshore. (2) The sea level amplification on the south coast is greater than that on the north coast. When river discharge increases by 20,000 m3/s, the sea level will increase by 0.005-0.010 m in most of Hangzhou Bay. (3) The sea level at the Dajishan station, influenced by river discharge, increased 0.178 mm/y from 1980 to 2011. Correspondingly, the sea level rose at a rate of 2.6-3.0 mm/y during the same period. These values were provided by the CSLB. The increase in sea level (1980-2011) at the Dajishan station caused by river discharge is 6.8-8.9% of the total increase in sea level. (4) The 19-20 year dominant nodal cycle of sea level at the Dajishan and Lvsi stations is in accord with 18.6 year nodal cycle of main tidal constituents on Chinese coasts. It implies that the sea-level change period on the

  6. Assessment of potential effects of water produced from coalbed natural gas development on macroinvertebrate and algal communities in the Powder River and Tongue River, Wyoming and Montana, 2010

    USGS Publications Warehouse

    Peterson, David A.; Hargett, Eric G.; Feldman, David L.

    2011-01-01

    Ongoing development of coalbed natural gas in the Powder River structural basin in Wyoming and Montana led to formation of an interagency aquatic task group to address concerns about the effects of the resulting production water on biological communities in streams of the area. Ecological assessments, made from 2005–08 under the direction of the task group, indicated biological condition of the macroinvertebrate and algal communities in the middle reaches of the Powder was lower than in the upper or lower reaches. On the basis of the 2005–08 results, sampling of the macroinvertebrate and algae communities was conducted at 18 sites on the mainstem Powder River and 6 sites on the mainstem Tongue River in 2010. Sampling-site locations were selected on a paired approach, with sites located upstream and downstream of discharge points and tributaries associated with coalbed natural gas development. Differences in biological condition among site pairs were evaluated graphically and statistically using multiple lines of evidence that included macroinvertebrate and algal community metrics (such as taxa richness, relative abundance, functional feeding groups, and tolerance) and output from observed/expected (O/E) macroinvertebrate models from Wyoming and Montana. Multiple lines of evidence indicated a decline in biological condition in the middle reaches of the Powder River, potentially indicating cumulative effects from coalbed natural gas discharges within one or more reaches between Flying E Creek and Wild Horse Creek in Wyoming. The maximum concentrations of alkalinity in the Powder River also occurred in the middle reaches. Biological condition in the upper and lower reaches of the Powder River was variable, with declines between some site pairs, such as upstream and downstream of Dry Fork and Willow Creek, and increases at others, such as upstream and downstream of Beaver Creek. Biological condition at site pairs on the Tongue River showed an increase in one case

  7. Estimating extreme river discharges in Europe through a Bayesian network

    NASA Astrophysics Data System (ADS)

    Paprotny, Dominik; Morales-Nápoles, Oswaldo

    2017-06-01

    Large-scale hydrological modelling of flood hazards requires adequate extreme discharge data. In practise, models based on physics are applied alongside those utilizing only statistical analysis. The former require enormous computational power, while the latter are mostly limited in accuracy and spatial coverage. In this paper we introduce an alternate, statistical approach based on Bayesian networks (BNs), a graphical model for dependent random variables. We use a non-parametric BN to describe the joint distribution of extreme discharges in European rivers and variables representing the geographical characteristics of their catchments. Annual maxima of daily discharges from more than 1800 river gauges (stations with catchment areas ranging from 1.4 to 807 000 km2) were collected, together with information on terrain, land use and local climate. The (conditional) correlations between the variables are modelled through copulas, with the dependency structure defined in the network. The results show that using this method, mean annual maxima and return periods of discharges could be estimated with an accuracy similar to existing studies using physical models for Europe and better than a comparable global statistical model. Performance of the model varies slightly between regions of Europe, but is consistent between different time periods, and remains the same in a split-sample validation. Though discharge prediction under climate change is not the main scope of this paper, the BN was applied to a large domain covering all sizes of rivers in the continent both for present and future climate, as an example. Results show substantial variation in the influence of climate change on river discharges. The model can be used to provide quick estimates of extreme discharges at any location for the purpose of obtaining input information for hydraulic modelling.

  8. Landscape co-evolution and river discharge.

    NASA Astrophysics Data System (ADS)

    van der Velde, Ype; Temme, Arnaud

    2015-04-01

    Fresh water is crucial for society and ecosystems. However, our ability to secure fresh water resources under climatic and anthropogenic change is impaired by the complexity of interactions between human society, ecosystems, soils, and topography. These interactions cause landscape properties to co-evolve, continuously changing the flow paths of water through the landscape. These co-evolution driven flow path changes and their effect on river runoff are, to-date, poorly understood. In this presentation we introduce a spatially distributed landscape evolution model that incorporates growing vegetation and its effect on evapotranspiration, interception, infiltration, soil permeability, groundwater-surface water exchange and erosion. This landscape scale (10km2) model is calibrated to evolve towards well known empirical organising principles such as the Budyko curve and Hacks law under different climate conditions. To understand how positive and negative feedbacks within the model structure form complex landscape patterns of forests and peat bogs that resemble observed landscapes under humid and boreal climates, we analysed the effects of individual processes on the spatial distribution of vegetation and river peak and mean flows. Our results show that especially river peak flows and droughts decrease with increasing evolution of the landscape, which is a result that has direct implications for flood management.

  9. Plasma Treatment of Polyethylene Powder Particles in Hollow Cathode Glow Discharge

    SciTech Connect

    Wolter, Matthias; Quitzau, Meike; Bornholdt, Sven; Kersten, Holger

    2008-09-07

    Polyethylen (PE) is widely used in the production of foils, insulators, packaging materials, plastic bottles etc. Untreated PE is hydrophobic due to its unpolar surface. Therefore, it is hard to print or glue PE and the surface has to be modified before converting.In the present experiments a hollow cathode glow discharge is used as plasma source which is mounted in a spiral conveyor in order to ensure a combines transport of PE powder particles. With this set-up a homogeneous surface treatment of the powder is possible while passing the glow discharge. The plasma treatment causes a remarkable enhancement of the hydrophilicity of the PE powder which can be verified by contact angle measurements and X-ray photoelectron spectroscopy.

  10. Effect of TiN powder mixed in Electrical Discharge Machining

    NASA Astrophysics Data System (ADS)

    Muttamara, A.; Mesee, J.

    2016-11-01

    Many trials were studied about powder mixed in Electrical Discharge Machining (EDM). The experiments were carried for improving surface characteristics and related to the surface modification. The experiment was carried out using a copper tool electrode and EDMed in titanium nitride (TiN) powder mixed in dielectric fluid. In this research, to obtain the even modified layer, the effects of EDMed conditions were investigated. The EDMed surfaces were observed by SEM. Under the suitable discharge conditions in TiN powder mixed kerosene, the stable thick TiN layer adhered on the workpiece surface. The microcrack length per unit area treated in TiN mixed kerosene was greater than that treated in normal kerosene. Titanium carbon nitride (TiCN) was found on the modified layer by XRD analysis. The effect of the diffusion of carbon during cooling on the characteristics of the recast layer was discussed.

  11. Constructing river stage-discharge rating curves using remotely sensed river cross-sectional inundation areas and river bathymetry

    NASA Astrophysics Data System (ADS)

    Pan, Feifei; Wang, Cheng; Xi, Xiaohuan

    2016-09-01

    Remote sensing from satellites and airborne platforms provides valuable data for monitoring and gauging river discharge. One effective approach first estimates river stage from satellite-measured inundation area based on the inundation area-river stage relationship (IARSR), and then the estimated river stage is used to compute river discharge based on the stage-discharge rating (SDR) curve. However, this approach is difficult to implement because of a lack of data for constructing the SDR curves. This study proposes a new method to construct the SDR curves using remotely sensed river cross-sectional inundation areas and river bathymetry. The proposed method was tested over a river reach between two USGS gauging stations, i.e., Kingston Mines (KM) and Copperas Creek (CC) along the Illinois River. First a polygon over each of two cross sections was defined. A complete IARSR curve was constructed inside each polygon using digital elevation model (DEM) and river bathymetric data. The constructed IARSR curves were then used to estimate 47 river water surface elevations at each cross section based on 47 river inundation areas estimated from Landsat TM images collected during 1994-2002. The estimated water surface elevations were substituted into an objective function formed by the Bernoulli equation of gradually varied open channel flow. A nonlinear global optimization scheme was applied to solve the Manning's coefficient through minimizing the objective function value. Finally the SDR curve was constructed at the KM site using the solved Manning's coefficient, channel cross sectional geometry and the Manning's equation, and employed to estimate river discharges. The root mean square error (RMSE) in the estimated river discharges against the USGS measured river discharges is 112.4 m3/s. To consider the variation of the Manning's coefficient in the vertical direction, this study also suggested a power-law function to describe the vertical decline of the Manning

  12. Benchmarking wide swath altimetry-based river discharge estimation algorithms for the Ganges river system

    NASA Astrophysics Data System (ADS)

    Bonnema, Matthew G.; Sikder, Safat; Hossain, Faisal; Durand, Michael; Gleason, Colin J.; Bjerklie, David M.

    2016-04-01

    The objective of this study is to compare the effectiveness of three algorithms that estimate discharge from remotely sensed observables (river width, water surface height, and water surface slope) in anticipation of the forthcoming NASA/CNES Surface Water and Ocean Topography (SWOT) mission. SWOT promises to provide these measurements simultaneously, and the river discharge algorithms included here are designed to work with these data. Two algorithms were built around Manning's equation, the Metropolis Manning (MetroMan) method, and the Mean Flow and Geomorphology (MFG) method, and one approach uses hydraulic geometry to estimate discharge, the at-many-stations hydraulic geometry (AMHG) method. A well-calibrated and ground-truthed hydrodynamic model of the Ganges river system (HEC-RAS) was used as reference for three rivers from the Ganges River Delta: the main stem of Ganges, the Arial-Khan, and the Mohananda Rivers. The high seasonal variability of these rivers due to the Monsoon presented a unique opportunity to thoroughly assess the discharge algorithms in light of typical monsoon regime rivers. It was found that the MFG method provides the most accurate discharge estimations in most cases, with an average relative root-mean-squared error (RRMSE) across all three reaches of 35.5%. It is followed closely by the Metropolis Manning algorithm, with an average RRMSE of 51.5%. However, the MFG method's reliance on knowledge of prior river discharge limits its application on ungauged rivers. In terms of input data requirement at ungauged regions with no prior records, the Metropolis Manning algorithm provides a more practical alternative over a region that is lacking in historical observations as the algorithm requires less ancillary data. The AMHG algorithm, while requiring the least prior river data, provided the least accurate discharge measurements with an average wet and dry season RRMSE of 79.8% and 119.1%, respectively, across all rivers studied. This poor

  13. Discharge in the lower Columbia River basin, 1928-65

    USGS Publications Warehouse

    Orem, Hollis M.

    1968-01-01

    Estimates of monthly and annual mean discharge for five ungaged sites in the lower Columbia River are presented for water years 1928-65. These sites are Columbia River at Vancouver, Wash., Willamette River at mouth, Columbia River at St. Helens, Oreg., Columbia River at Longview, Wash., and Columbia River at mouth. Two tables of estimates are compiled for each site. One table lists estimates of 'observed' flow, the flows that would be measured by a gaging station. The other table lists 'adjusted' flows, the 'observed' flows adjusted for storage changes in major reservoirs arid for diversion at Grand Coulee Dam. Two methods are used in making these estimates. One method involves a detailed summation of flows from all gaged and ungaged areas, allowance for precipitation on and evaporation from the channel water surface, and adjustment of flow to allow for travel time from gaging stations at the Dalles, Oreg. (Columbia River main stem), and at Salem Oreg. (Willamette River). The other method is the same as the summation method except that flows from individual gaged and ungaged areas below The Dalles and Salem are not summed in detail. Instead, the entire drainage area below The Dalles is divided into three major inflow segments and the flow from each segment is obtained from a correlation with streams that are representative of the flow from that segment. Estimates of monthly mean flows are considered to be accurate within 2 or 3 percent.

  14. Incorporating safety into surface haulage in the Powder River basin

    SciTech Connect

    Jeffery, W.; Jennings, C.

    1996-12-31

    The Powder River Basin (PRB) coal deposit extends from southeast Montana to northeast Wyoming. This paper describes a number of haulage practices and tools in use at several mines of the southern PRB and the way in which safety has been designed into and implemented for surface haulage of coal and overburden. Experiences described herein focus on the northeastern corner of Wyoming. All the mines in this area rely on safe and efficient movement of enormous volumes of material, and the results achieved in safety underscore the planning and attention to detail present in the PRB. There are currently 12 large surface mines (those greater than 10.0MM tons/year) operating in this area. In 1995, these mines produced over 230.0MM tons of coal.

  15. River salinity variations in response to discharge: Examples from Western United States during early 1900s

    USGS Publications Warehouse

    Peterson, D.H.; Dettinger, M.D.; Cayan, D.R.; DiLeo, J.; Isaacs, C.; Riddle, L.; Smith, R.

    1996-01-01

    Major controls on river salinity (total dissolved solids) in the western United States are climate, geology, and human activity.  Climate, in general, influences soil-river salinity via salt-balance variations.  When climate becomes wetter, river discharge increases and soil-river salinity descreases; when climate becomes drier river discharge decreases and soil-river salinity increases.  This study characterizes the river salinity response to discharge using statistical-dynamical methods.  An exploratory analysis of river salinity, using early 1900s water quality surveys in the western United States, shows much river salinity variability is in response to storm and annual discharge.  Presumably this is because river discharge is largely supported by surface flow.

  16. Increasing summer river discharge in urbanized watersheds in southern California

    NASA Astrophysics Data System (ADS)

    Townsend-Small, A.; Nash, D.; Finan, K.; Liu, H.; Thomas, B.; Li, Z.; Wu, Q.

    2012-12-01

    Urban areas alter hydrologic flowpaths through increased impermeable surface area, which leads to a greater proportion of runoff versus infiltration during rain events. In semi-arid regions, however, there may be an additional impact of urbanization on stream flow rates via increased dry-season runoff due to landscaping irrigation and sewage treatment plant effluent. In this presentation, we will show that summer river discharge is increasing in urban and suburban southern California, USA, despite a lack of summer precipitation. The data were collected online from the USGS stream gauge network. The Los Angeles area megacity relies heavily on imported water from northern and western parts of California and the other parts of the southwestern USA. This water transportation network is a large drain on water resources in source regions and is one of the largest electricity consumers in the state. A close analysis of the streamflow data along with satellite-derived land cover data indicate that summer river discharge is low to nonexistent in most undeveloped watersheds, with no temporal trend, while urban and suburban river discharge has been increasing throughout the past 50 or 60 years. This has important implications for water policy in California, as water resources are expected to become more scarce with decreasing snowpack in the Sierra Nevada mountains. There are also potential health impacts for this research, as urban runoff can cause high bacterial counts and beach closures in this region. Potential causes for increasing summer river discharge will be discussed as well as suggestions for remediation and conservation.

  17. Dissemination of satellite-based river discharge and flood data

    NASA Astrophysics Data System (ADS)

    Kettner, A. J.; Brakenridge, G. R.; van Praag, E.; de Groeve, T.; Slayback, D. A.; Cohen, S.

    2014-12-01

    In collaboration with NASA Goddard Spaceflight Center and the European Commission Joint Research Centre, the Dartmouth Flood Observatory (DFO) daily measures and distributes: 1) river discharges, and 2) near real-time flood extents with a global coverage. Satellite-based passive microwave sensors and hydrological modeling are utilized to establish 'remote-sensing based discharge stations', and observed time series cover 1998 to the present. The advantages over in-situ gauged discharges are: a) easy access to remote or due to political reasons isolated locations, b) relatively low maintenance costs to maintain a continuous observational record, and c) the capability to obtain measurements during floods, hazardous conditions that often impair or destroy in-situ stations. Two MODIS instruments aboard the NASA Terra and Aqua satellites provide global flood extent coverage at a spatial resolution of 250m. Cloud cover hampers flood extent detection; therefore we ingest 6 images (the Terra and Aqua images of each day, for three days), in combination with a cloud shadow filter, to provide daily global flood extent updates. The Flood Observatory has always made it a high priority to visualize and share its data and products through its website. Recent collaborative efforts with e.g. GeoSUR have enhanced accessibility of DFO data. A web map service has been implemented to automatically disseminate geo-referenced flood extent products into client-side GIS software. For example, for Latin America and the Caribbean region, the GeoSUR portal now displays current flood extent maps, which can be integrated and visualized with other relevant geographical data. Furthermore, the flood state of satellite-observed river discharge sites are displayed through the portal as well. Additional efforts include implementing Open Geospatial Consortium (OGC) standards to incorporate Water Markup Language (WaterML) data exchange mechanisms to further facilitate the distribution of the satellite

  18. Initiation of detonation by a high-voltage discharge in powdered explosives with nanosize inert admixtures

    NASA Astrophysics Data System (ADS)

    Rashkovskii, S. A.; Savenkov, G. G.

    2013-04-01

    It is shown that admixtures of a copper nanopowder in a high-disperse low-sensitivity explosive of the FOX-7 type sharply increase the sensitivity of the mixture to the action of a high-voltage electric discharge and facilitate detonation. The percolation model of propagation of the electric breakdown over a powdered mixture with nanosize admixtures and the model of initiation of detonation by a high-voltage discharge in the mixture of a brisant explosive with an inert admixture are developed. These models are in qualitative and quantitative agreement with experimental data.

  19. Invasive species and coal bed methane development in the Powder River Basin, Wyoming.

    PubMed

    Bergquist, E; Evangelista, P; Stohlgren, T J; Alley, N

    2007-05-01

    One of the fastest growing areas of natural gas production is coal bed methane (CBM) due to the large monetary returns and increased demand for energy from consumers. The Powder River Basin, Wyoming is one of the most rapidly expanding areas of CBM development with projections of the establishment of up to 50,000 wells. CBM disturbances may make the native ecosystem more susceptible to invasion by non-native species, but there are few studies that have been conducted on the environmental impacts of this type of resource extraction. To evaluate the potential effects of CBM development on native plant species distribution and patterns of non-native plant invasion, 36 modified Forest Inventory and Analysis plots (each comprised of four 168-m2 subplots) were established in the Powder River Basin, Wyoming. There were 73 168-m2 subplots on control sites; 42 subplots on secondary disturbances; 14 on major surface disturbances; eight on well pads; and seven on sites downslope of CBM wells water discharge points. Native plant species cover ranged from 39.5 +/- 2.7% (mean +/- 1 SE) in the secondary disturbance subplots to 17.7 +/- 7.5% in the pad subplots. Non-native plant species cover ranged from 31.0 +/- 8.4% in the discharge areas to 14.7 +/- 8.9% in the pad subplots. The control subplots had significantly less non-native species richness than the combined disturbance types. The combined disturbance subplots had significantly greater soil salinity than the control sites. These results suggest that CBM development and associated disturbances may facilitate the establishment of non-native plants. Future research and management decisions should consider the accumulative landscape-scale effects of CBM development on preserving native plant diversity.

  20. Invasive species and coal bed methane development in the Powder River Basin, Wyoming

    USGS Publications Warehouse

    Bergquist, E.; Evangelista, P.; Stohlgren, T.J.; Alley, N.

    2007-01-01

    One of the fastest growing areas of natural gas production is coal bed methane (CBM) due to the large monetary returns and increased demand for energy from consumers. The Powder River Basin, Wyoming is one of the most rapidly expanding areas of CBM development with projections of the establishment of up to 50,000 wells. CBM disturbances may make the native ecosystem more susceptible to invasion by non-native species, but there are few studies that have been conducted on the environmental impacts of this type of resource extraction. To evaluate the potential effects of CBM development on native plant species distribution and patterns of non-native plant invasion, 36 modified Forest Inventory and Analysis plots (each comprised of four 168-m2 subplots) were established in the Powder River Basin, Wyoming. There were 73 168-m2 subplots on control sites; 42 subplots on secondary disturbances; 14 on major surface disturbances; eight on well pads; and seven on sites downslope of CBM wells water discharge points. Native plant species cover ranged from 39.5 ?? 2.7% (mean ?? 1 SE) in the secondary disturbance subplots to 17.7 ?? 7.5% in the pad subplots. Non-native plant species cover ranged from 31.0 ?? 8.4% in the discharge areas to 14.7 ?? 8.9% in the pad subplots. The control subplots had significantly less non-native species richness than the combined disturbance types. The combined disturbance subplots had significantly greater soil salinity than the control sites. These results suggest that CBM development and associated disturbances may facilitate the establishment of non-native plants. Future research and management decisions should consider the accumulative landscape-scale effects of CBM development on preserving native plant diversity. ?? Springer Science+Business Media B.V. 2006.

  1. Response of salinity distribution around the Yellow River mouth to abrupt changes in river discharge

    NASA Astrophysics Data System (ADS)

    Wang, Yucheng; Liu, Zhe; Gao, Huiwang; Ju, Lian; Guo, Xinyu

    2011-04-01

    To investigate how salinity changes with abrupt increases and decreases in river discharge, three surveys were conducted along six sections around the Yellow River mouth before, during and after a water regulation event during which the river discharge was increased from ˜200 to >3000 m 3 s -1 for the first 3 days, was maintained at >3000 m 3 s -1 for the next 9 days and was decreased to <1000 m 3 s -1 for the final 4 days. The mean salinity in the Yellow River estuary area during the event varied ˜1.21, which is much larger than its seasonal variation (˜0.50) and interannual variation (˜0.05). Before the event, a small plume was observed near the river mouth. During the event, the plume extended over 24 km offshore in the surface layer in the direction of river water outflow. After the event, the plume diminished in size but remained larger than before the event. The downstream propagation of the plume (as in a Kelvin wave sense) was apparent in the bottom layer during the second survey and in both the surface and bottom layers during the third survey. The plume sizes predicted by the formulas from theoretical studies are larger than those we observed, indicating that factors neglected by theoretical studies such as the temporal variation in river discharge and vertical mixing in the sea could be very important for plume evolution. In addition to the horizontal variation of the plume, we also observed the penetration of freshwater from the surface layer into the bottom layer. A comparison of two vertical processes, wind mixing and tidal mixing, suggests that the impact of wind mixing may be comparable with that of tidal mixing in the area close to the river mouth and may be dominant over offshore areas. The change in Kelvin number indicates an alteration of plume dynamics due to the abrupt change in river discharge during the water regulation event.

  2. Mechanism of Electro-Static Discharge (ESD) Sensitivity of Reactive Powders and Its Mitigation

    DTIC Science & Technology

    2011-03-14

    occurring at early stages of spark plasma sintering (SPS) [59]. While it is relatively well described in the literature, the mechanisms governing the...changes in the conductivity of non-equilibrium plasma existing in the spark gap [36–37], and due to changes in the properties of Mg powder while it is... Spark discharge breaks down the air gap producing a relatively narrow (~ 100 µm diameter) [37, 39] plasma channel with a small resistance. When an

  3. Modeling Late Quaternary discharge of the Mississippi River system

    SciTech Connect

    Craig, R.G.; Orndorff, R. . Dept. of Geology)

    1992-01-01

    The authors estimate discharge in the Mississippi River system during various stages of Lake Agassiz and configurations of the Laurentide Ice Sheet, using a numerical representation of elements defining the hydrologic system. Ice sheet margins and isostatic depression due to ice sheet load are digitized from published maps. Terrain is represented with a digital elevation model (DEM) at 10 km spacing. Drainage, and the positions of ice marginal lakes are computed from the DEM after superposing the ice sheet configuration and isostatic depression. Meltwater supply is computed using the method of Teller (1990). Non-glacial runoff is computed as a constant change (nominally 2x) from published modern values of unit area runoff. Computations are limited to average annual values; short term floods and seasonal variations are not represented. They test the model by comparisons of discharge estimates--using modern drainage configurations and runoff values--to those available from gauging stations. They also compare their estimate of glacial discharge, without increasing modern non-glacial runoff, to that of Teller (1990). Using Laurentide runoff and incremented non-glacial discharge estimates based on paleoclimatic evidence, they compute significantly larger discharges than those reported by Teller (1990). This is primarily due to increased non-glacial runoff. This model provides a basis for pointwise comparisons to field evidence at critical sites.

  4. Characterization of Ni ferrites powders prepared by plasma arc discharge process

    NASA Astrophysics Data System (ADS)

    Safari, A.; Gheisari, Kh.; Farbod, M.

    2017-01-01

    The aim of this work was to synthesize a single-phase spinel structure from a mixture of zinc, iron and nickel powders by plasma arc discharge method. A mixture of zinc, iron and nickel powders with the appropriate molar ratio was prepared and formed into a cylindrical shape. The synthesis process was performed in air, oxygen and argon atmospheres with the applied arc current of 400 A and pressure of 1 atm. After establishing an arc between the electrodes, the produced powders were collected and their structure and magnetic properties were examined by XRD and VSM, respectively. ZnO as an impurity was appeared in the as-produced powders owing to the high reactivity of zinc atoms, preventing the formation of Ni-Zn ferrite. A pure spinel structure with the highest saturation magnetization (43.8 emu/g) was observed as zinc powders removed completely from the initial mixture. Morphological evaluations using field emission scanning electron microscopy showed that the mean size of fabricated nanoparticles was in the range 100-200 nm and was dependent on the production conditions.

  5. Stratigraphy, depositional history, and petroleum geology of Lower Cretaceous Fall River formation, Powder River Basin, Wyoming

    SciTech Connect

    Ryer, T.A.; Gustason, E.R.

    1985-05-01

    The middle Albian Fall River Formation, better know to petroleum geologists as the Dakota Sandstone, constitutes a northwestward-thinning wedge of predominantly sandy strata under and overlain by marine shale. Two major episodes of deltaic progradation can be recognized in the formation, permitting mapping of lower and upper deltaic members. Study of outcrops, cores, and subsurface relationships indicates that the Fall River consists predominantly of fluvial strata in the southeastern part of the Powder River basin; delta-front and delta-plain facies, which are cut out and replaced locally by northwest-trending meander belts, predominate in an area that tends northeastward across the central part of the basin; the delta-front facies pinches out into offshore marine shale in the northwestern part of the basin. The large majority of Fall River stratigraphic trap-type fields produce oil and gas from sandy meander-belt deposits. The largest accumulations of hydrocarbons in traps of this type, as exemplified by the Powell-Mexican Springs trend (lower member) and the Coyote Creek-Miller Creek trend (upper member), occur in the more seaward parts of the deltaic members, near the seaward termini of meander-belt systems. Mapping of meander belts and of the surrounding deltaic deposits constitutes a necessary first step in exploration for stratigraphic traps within the Fall River Formation.

  6. Estimation of Shallow Groundwater Discharge and Nutrient Load into a River

    Treesearch

    Ying Ouyang

    2012-01-01

    Pollution of rivers with excess nutrients due to groundwater discharge, storm water runoff, surface loading,and atmospheric deposition is an increasing environmental concern worldwide. While the storm water runoff and surface loading of nutrients into many rivers have been explored in great detailed, the groundwater discharge of nutrients into the rivers has not yet...

  7. Field intercomparison of channel master ADCP with RiverSonde Radar for measuring river discharge

    USGS Publications Warehouse

    Spain, P.; Marsden, R.; Barrick, D.; Teague, C.; Ruhl, C.

    2005-01-01

    The RiverSonde radar makes non-contact measurement of a horizontal swath of surface velocity across a river section. This radar, which has worked successfully at several rivers in the Western USA, has shown encouraging correlation with simultaneous measurements of average currents at one level recorded by an acoustic travel-time system. This work reports a field study intercomparing data sets from a 600 kHz Channel Master ADCP with the RiverSonde radar. The primary goal was to begin to explore the robustness of the radar data as a reliable index of discharge. This site Is at Three Mile Slough in Northern California, USA. The larger intent of the work is to examine variability in space and time of the radar's surface currents compared with subsurface flows across the river section. Here we examine data from a couple of periods with strong winds. ?? 2005 IEEE.

  8. Effects of river discharge and tidal asymmetry on residual sediment transport and long-term morphodynamics in the river estuary

    NASA Astrophysics Data System (ADS)

    Guo, L.; Van der Wegen, M.; Roelvink, J.; He, Q.

    2013-12-01

    The morphodynamics are of ubiquitous importance to the estuarine function with respect to navigation and ecology. This study examines the hydrodynamics, residual sediment transport processes and long-term morphodynamics in the river estuary forced by river discharge and marine tides. We systematically investigated the generation of tidal asymmetry and its modulation by varying river discharges, the interactions between the river discharge and the tides, and the induced residual sediment transport and associated morphodynamic adjustment and then the feedback mechanisms by deploying the Delft3D model in 1D mode. The model shows that the internally generated tidal asymmetry behaves nonlinearly with increasing river discharge. The internal tidal asymmetry is flood dominated in the absence of river discharge and tidal flat. Introduction of a river discharge promotes the overtide generation which reinforces the tidal asymmetry. An increasing river discharge dissipates the tidal energy and damps the tides that the overtide generation is confined in the downstream. A river discharge threshed can be figured out at which the energy transformation from the principle tide (M2) to the overtide (M4) reaches maximum. The tidal averaged residual sediment transport is decomposed into components according to a bed load transport mode. The tidal asymmetry induces a residual sediment transport whose direction is determined by the nature of the tidal asymmetry. The river discharge induces a net seaward residual transport due to enhanced seaward residual current. Moreover, the interaction between the river discharge and tides generates a river-induced asymmetry. The river-induced asymmetry enhances the seaward residual sediment transport to a large degree that it plays a significant role in flushing sediment seaward. The estuarine morphodynamics reach a (quasi-) equilibrium in a time scale of millennia. The morphodynamic equilibrium is characterized by a reducing longitudinal residual

  9. Using HEM surveys to evaluate disposal of by-product water from CBNG development in the Powder River Basin, Wyoming

    SciTech Connect

    Lipinski, Brian A.; Sams, James I.; Smith, Bruce D.; Harbert, William

    2008-05-01

    Production of methane from thick, extensive coal beds in the Powder River Basin of Wyoming has created water management issues. Since development began in 1997, more than 650 billion liters of water have been produced from approximately 22,000 wells. Infiltration impoundments are used widely to dispose of by-product water from coal bed natural gas (CBNG) production, but their hydrogeologic effects are poorly understood. Helicopter electromagnetic surveys (HEM) were completed in July 2003 and July 2004 to characterize the hydrogeology of an alluvial aquifer along the Powder River. The aquifer is receiving CBNG produced water discharge from infiltration impoundments. HEM data were subjected to Occam's inversion algorithms to determine the aquifer bulk conductivity, which was then correlated to water salinity using site-specific sampling results. The HEM data provided high-resolution images of salinity levels in the aquifer, a result not attainable using traditional sampling methods. Interpretation of these images reveals clearly the produced water influence on aquifer water quality. Potential shortfalls to this method occur where there is no significant contrast in aquifer salinity and infiltrating produced water salinity and where there might be significant changes in aquifer lithology. Despite these limitations, airborne geophysical methods can provide a broadscale (watershed-scale) tool to evaluate CBNG water disposal, especially in areas where field-based investigations are logistically prohibitive. This research has implications for design and location strategies of future CBNG water surface disposal facilities within the Powder River Basin.

  10. Using HEM surveys to evaluate disposal of by-product water from CBNG development in the Powder River Basin, Wyoming

    USGS Publications Warehouse

    Lipinski, B.A.; Sams, J.I.; Smith, B.D.; Harbert, W.

    2008-01-01

    Production of methane from thick, extensive coal beds in the Powder River Basin of Wyoming has created water management issues. Since development began in 1997, more than 650 billion liters of water have been produced from approximately 22,000 wells. Infiltration impoundments are used widely to dispose of by-product water from coal bed natural gas (CBNG) production, but their hydrogeologic effects are poorly understood. Helicopter electromagnetic surveys (HEM) were completed in July 2003 and July 2004 to characterize the hydrogeology of an alluvial aquifer along the Powder River. The aquifer is receiving CBNG produced water discharge from infiltration impoundments. HEM data were subjected to Occam's inversion algorithms to determine the aquifer bulk conductivity, which was then correlated towater salinity using site-specific sampling results. The HEM data provided high-resolution images of salinity levels in the aquifer, a result not attainable using traditional sampling methods. Interpretation of these images reveals clearly the produced water influence on aquifer water quality. Potential shortfalls to this method occur where there is no significant contrast in aquifer salinity and infiltrating produced water salinity and where there might be significant changes in aquifer lithology. Despite these limitations, airborne geophysical methods can provide a broadscale (watershed-scale) tool to evaluate CBNG water disposal, especially in areas where field-based investigations are logistically prohibitive. This research has implications for design and location strategies of future CBNG water surface disposal facilities within the Powder River Basin. ?? 2008 2008 Society of ExplorationGeophysicists. All rights reserved.

  11. Using HEM surveys to evaluate disposal of by-product water from CBNG development in the Powder River Basin, Wyoming

    SciTech Connect

    Lipinski, B.A.; Sams, J.I.; Smith, B.D.; Harbert, W.P.

    2008-05-01

    Production of methane from thick, extensive coal beds in the Powder River Basin ofWyoming has created water management issues. Since development began in 1997, more than 650 billion liters of water have been produced from approximately 22,000 wells. Infiltration impoundments are used widely to dispose of by-product water from coal bed natural gas (CBNG) production, but their hydrogeologic effects are poorly understood. Helicopter electromagnetic surveys (HEM) were completed in July 2003 and July 2004 to characterize the hydrogeology of an alluvial aquifer along the Powder River. The aquifer is receiving CBNG produced water discharge from infiltration impoundments. HEM data were subjected to Occam’s inversion algorithms to determine the aquifer bulk conductivity, which was then correlated to water salinity using site-specific sampling results. The HEM data provided high-resolution images of salinity levels in the aquifer, a result not attainable using traditional sampling methods. Interpretation of these images reveals clearly the produced water influence on aquifer water quality. Potential shortfalls to this method occur where there is no significant contrast in aquifer salinity and infiltrating produced water salinity and where there might be significant changes in aquifer lithology. Despite these limitations, airborne geophysical methods can provide a broadscale (watershed-scale) tool to evaluate CBNG water disposal, especially in areas where field-based investigations are logistically prohibitive. This research has implications for design and location strategies of future CBNG water surface disposal facilities within the Powder River Basin.

  12. Warming Oceans, Phytoplankton, and River Discharge: Implications for Cholera Outbreaks

    PubMed Central

    Jutla, Antarpreet S.; Akanda, Ali S.; Griffiths, Jeffrey K.; Colwell, Rita; Islam, Shafiqul

    2011-01-01

    Phytoplankton abundance is inversely related to sea surface temperature (SST). However, a positive relationship is observed between SST and phytoplankton abundance in coastal waters of Bay of Bengal. This has led to an assertion that in a warming climate, rise in SST may increase phytoplankton blooms and, therefore, cholera outbreaks. Here, we explain why a positive SST-phytoplankton relationship exists in the Bay of Bengal and the implications of such a relationship on cholera dynamics. We found clear evidence of two independent physical drivers for phytoplankton abundance. The first one is the widely accepted phytoplankton blooming produced by the upwelling of cold, nutrient-rich deep ocean waters. The second, which explains the Bay of Bengal findings, is coastal phytoplankton blooming during high river discharges with terrestrial nutrients. Causal mechanisms should be understood when associating SST with phytoplankton and subsequent cholera outbreaks in regions where freshwater discharge are a predominant mechanism for phytoplankton production. PMID:21813852

  13. River discharge reduces reef coral diversity in Palau.

    PubMed

    Golbuu, Yimnang; van Woesik, Robert; Richmond, Robert H; Harrison, Peter; Fabricius, Katharina E

    2011-04-01

    Coral community structure is often governed by a suite of processes that are becoming increasingly influenced by land-use changes and related terrestrial discharges. We studied sites along a watershed gradient to examine both the physical environment and the associated biological communities. Transplanted corals showed no differences in growth rates and mortality along the watershed gradient. However, coral cover, coral richness, and coral colony density increased with increasing distance from the mouth of the bay. There was a negative relationship between coral cover and mean suspended solids concentration. Negative relationships were also found between terrigenous sedimentation rates and the richness of adult and juvenile corals. These results have major implications not only for Pacific islands but for all countries with reef systems downstream of rivers. Land development very often leads to increases in river runoff and suspended solids concentrations that reduce coral cover and coral diversity on adjacent reefs.

  14. Environmental fate of mercury discharged into the upper Wisconsin River

    USGS Publications Warehouse

    Rada, R.G.; Findley, J.E.; Wiener, J.G.

    1986-01-01

    The authors studied the distribution of Hg in sediments, fish, and crayfish in a 60 km reach of the Upper Wisconsin River that formerly received Hg in discharges from pulp and paper mills. The most heavily contaminated strata of sediments were deposited during the 1950s and early 1960s and buried under subsequent deposits; however, surficial sediments remained substantially enriched at certain sites in 1981. Median concentrations of Hg in surficial sediments, adjusted for grain size, were at least 10-fold greater at the main study area than at an upstream reference site. Total concentrations exceeded 1.0 mu g g super(-1) wet weight in axial muscle tissue in only 2 of 173 fish analyzed from the study area; however, historical comparisons revealed that Hg contamination of fish (common carp Cyprinus carpio and walleye Stizostedion vitreum vitreum ) and crayfish (Orconectes ) in the river had not decreased since the early 1970s.

  15. Status report: USGS coal assessment of the Powder River, Wyoming

    USGS Publications Warehouse

    Luppens, James A.; Rohrbacher, Timothy J.; Haacke, Jon E.; Scott, David C.; Osmonson, Lee M.

    2006-01-01

    Summary: This publication reports on the status of the current coal assessment of the Powder River Basin (PRB) in Wyoming and Montana. This slide program was presented at the Energy Information Agency's 2006 EIA Energy Outlook and Modeling Conference in Washington, DC, on March 27, 2006. The PRB coal assessment will be the first USGS coal assessment to include estimates of both regional coal resources and reserves for an entire coal basin. Extensive CBM and additional oil and gas development, especially in the Gillette coal field, have provided an unprecedented amount of down-hole geological data. Approximately 10,000 new data points have been added to the PRB database since the last assessment (2002) which will provide a more robust evaluation of the single most productive U.S. coal basin. The Gillette coal field assessment, including the mining economic evaluation, is planned for completion by the end of 2006. The geologic portion of the coal assessment work will shift to the northern and northwestern portions of the PRB before the end of 2006 while the Gillette engineering studies are finalized.

  16. Paleotectonics and hydrocarbon accumulation, Powder River basin, Wyoming

    SciTech Connect

    Slack, P.B.

    1981-04-01

    The Belle Fourche arch, a subtle northeast-trending paleoarch, extends across the central part of the Powder River basin, Wyoming, to the Black Hills uplift. The arch is the result of differential vertical uplift, primarily during Cretaceous time, on numerous northeast-trending structural lineaments. Stratigraphic evidence suggests that the structural lineaments which form the Belle Fourche arch have rejuvenated periodically throughout the Phanerozoic. Evidence includes: (1) localization of Minnelusa Formation (Permian) hydrocarbon production along the crest of the arch; (2) localization of Dakota Formation (Cretaceous) alluvial point-bar production on the crest of the arch; (3) localization of lower Muddy Formation (Cretaceous) channel deposits parallel with, and on the downthrown sides of, lineament trends; (4) abrupt change in depositional strike of upper Muddy Formation (Cretaceous) marine bars close to the arch; (5) superposition of Turner sandstone (Cretaceous) channel deposits along the trends of Muddy channels; and (6) localization of virtually all significant Upper Cretaceous Shannon and Sussex sandstone offshore marine-bar production along the crest of the arch. Subtle uplift along the arch was persistent during at least lower Muddy through Sussex deposition, a period of about 35 m.y. 14 figures.

  17. Moving to the Powder River Basin in search of the American dream

    SciTech Connect

    Buchsbaum, L.

    2007-03-15

    As the Big Three American automakers cut jobs in Michigan, Wyoming's booming but isolated coal mining industry in the Powder River Basin is trying to lure some of these dissatisfied workers. DRM has attracted workers to the benefaction plant and P & H MinePro Services working on surface mining equipment has been successful, as have Peabody's Powder River coal subsidiary and Kiewitt's Buckshin mine. 2 photos.

  18. Retrieving river discharge from SWOT-like data time-series : a sample of rivers types

    NASA Astrophysics Data System (ADS)

    Garambois, Pierre-André; Roux, Hélène; Monnier, Jérôme

    2015-04-01

    The future Surface Water and Ocean Topography (SWOT) mission would provide new cartographic measurements of ocean surface and inland water surfaces dynamics, and especially river height, width and slope. The highlight of SWOT will be its almost global coverage and temporal revisits on the order of 1 to 4 times per 22 - days repeat cycle [1]. The estimation of hydraulic parameters from water surface observations is still an open question. Several methods have recently been proposed for retrieving river discharge from SWOT data ([2, 3, 4]). The method introduced by [2] and used in the present study is based on Manning equation. The first step consists in retrieving an equivalent bathymetry profile for a river given one in situ depth measurement and SWOT like data of the water surface, that is to say water elevation, free surface slope and width. From this equivalent bathymetry, the second step consists in solving mass and Manning equation in the least square sense. Nevertheless, for cases where no in situ measurement of water depth is available, it is still possible to solve a system formed by mass and Manning equations in the least square sense (or with other methods such as Bayesian ones, see e.g. [3]). The approach is tested with synthetic data generated from hydraulic models for several river reaches around the world (cf. [5]). We show that a good a priori knowledge of bathymetry and roughness is required for such methods. The identifiability of the roughness geometry couple is also investigated for different space time sampling and hydraulic regimes. Indeed, the knowledge of effective hydraulic representation and limitations might be a cornerstone in identifications of hydraulic or hydrologic variables through data assimilation chains. References [1] E. Rodriguez, "SWOT science requirements document," JPL document, JPL, 2012. [2] P. A. Garambois and J. Monnier, "Inference of river properties from remotly sensed observations of water surface," (minor revisions

  19. Effects of discharge on silver loading and transport in the Quinnipiac River, Connecticut.

    PubMed

    Rozan, T F; Hunter, K S

    2001-11-12

    Silver concentrations were measured in water and sediment samples collected from the Quinnipiac River in Connecticut. This river was chosen for study because of its history of industrialization and high levels of Ag contamination. Sewage treatment plant (STP) effluent accounts for approximately 15% of the total river discharge and approximately 60% of the dissolved Ag in the water column during baseflow conditions. Erosion of contaminated riverbank sediment is the primary source of particulate Ag in the river. Both dissolved and particulate Ag fractions vary as a function of river discharge. Increased discharge due to rain events decreases the relative importance of STP effluent, and thus dilutes the dissolved Ag concentration in the water column. Conversely, increasing discharge results in higher particulate Ag concentrations from increased erosion. The results of this study clearly indicate that both point and non-point sources contribute significantly to Ag loading in this river system, with the level of river discharge determining the relative importance of each.

  20. Using Cottonwood Dendrochronology to Reconstruct River Discharge and Floodplain Dynamics, Yellowstone River, Montana

    NASA Astrophysics Data System (ADS)

    Schook, D. M.; Friedman, J. M.; Rathburn, S. L.

    2014-12-01

    Ecosystems and societies worldwide have evolved to depend upon the timing and magnitude of river discharge, and understanding past flows can help guide modern water management. We used tree rings of riparian plains cottonwoods (Populus deltoides subsp. monilifera) to reconstruct the history of flow variation and channel migration of a 20 km reach of the Yellowstone River in eastern Montana. Dendrochronological flow reconstructions commonly use upland trees, but our study highlights the improved resolution when floodplain trees are integrated into the data set . Our sample of 240 cottonwoods dating back to 1751 permits flow reconstruction of the Yellowstone to before the voyage of Lewis and Clark. Our tree ring series intercorrelation coefficient is 0.58, and the ring width index correlates to annual discharge at R = 0.67. Flow reconstruction indicates that the decades of highest (1820s, 1850s) and lowest (1830s, 1900s) flows all occurred prior to the instrumental record, revealing the value of an extended perspective. Cottonwood age distribution indicates that, like other western rivers, the rate of channel migration on the Yellowstone declined in the 20th century. However, the Yellowstone uniquely lacks mainstem dams and substantial water extractions, revealing the occurrence of hydrological and ecological change on a relatively natural river. Our study reach is the most geomorphically active of the entire 1100 km river between Yellowstone National Park and the Missouri River, but cottonwood age distribution reveals that trees that have established since the 1960s are underrepresented. The lack of younger cottonwood trees is likely caused by a decline in river migration rates, which may be attributed to i) climate change directly leading to a decline in fluvial processes driving river migration, ii) a decoupling in the timing of the snowmelt runoff receding limb and cottonwood seed release, or iii) both. Even on this relatively unmodified river, it appears that

  1. A new method of quantifying discharge of small rivers into lakes and inland seas

    NASA Astrophysics Data System (ADS)

    Osadchiev, Alexander; Zavialov, Peter

    2014-05-01

    Continental discharge is an important component of the global hydrological cycle, providing the majority of the input part of the ocean water balance. Buoyant inflow usually causes surface density stratification at the large shelf areas, and plays a significant role in physical, chemical, and biological processes there that is especially important for the lakes and inland seas. Although there is a lack of discharge data for most of rivers in a global scale. Regular direct measurements of discharge are performed only for a relatively small number of rivers, generally the biggest ones or ones that flow through densely populated areas. Within this problem an indirect method of assuming a volume of river discharge was developed. The general idea of the method is the following. Firstly, the spatial surface spread of the plume generated by the considered river discharge is identified using high resolution satellite imagery of the coastal zone adjacent to the river estuary. Secondly, a series of numerical simulations of the river runoff spread is performed under various prescribed external forcing conditions which include the discharge rate. Varying forcing conditions we iteratively improve the accordance between simulated and observed river plumes therefore consequentially specifying the value of river discharge. The developed method was applied and validated against in situ date for several rivers feeding the Black Sea. Practical importance of this work consists in the fact, that the suggested method is an alternative for the expensive and laborious direct measurements of the river discharge, which are used nowadays.

  2. Hurricane Mitch: Peak Discharge for Selected River Reachesin Honduras

    USGS Publications Warehouse

    Smith, Mark E.; Phillips, Jeffrey V.; Spahr, Norman E.

    2002-01-01

    Hurricane Mitch began as a tropical depression in the Caribbean Sea on 22 October 1998. By 26 October, Mitch had strengthened to a Category 5 storm as defined by the Saffir-Simpson Hurricane Scale (National Climate Data Center, 1999a), and on 27 October was threatening the northern coast of Honduras (fig. 1). After making landfall 2 days later (29 October), the storm drifted south and west across Honduras, wreaking destruction throughout the country before reaching the Guatemalan border on 31 October. According to the National Climate Data Center of the National Oceanic and Atmospheric Administration (National Climate Data Center, 1999b), Hurricane Mitch ranks among the five strongest storms on record in the Atlantic Basin in terms of its sustained winds, barometric pressure, and duration. Hurricane Mitch also was one of the worst Atlantic storms in terms of loss of life and property. The regionwide death toll was estimated to be more than 9,000; thousands of people were reported missing. Economic losses in the region were more than $7.5 billion (U.S. Agency for International Development, 1999). Honduras suffered the most widespread devastation during the storm. More than 5,000 deaths, and economic losses of more than $4 billion, were reported by the Government of Honduras. Honduran officials estimated that Hurricane Mitch destroyed 50 years of economic development. In addition to the human and economic losses, intense flooding and landslides scarred the Honduran landscape - hydrologic and geomorphologic processes throughout the country likely will be affected for many years. As part of the U.S. Government's response to the disaster, the U.S. Geological Survey (USGS) conducted post-flood measurements of peak discharge at 16 river sites throughout Honduras (fig. 2). Such measurements, termed 'indirect' measurements, are used to determine peak flows when direct measurements (using current meters or dye studies, for example) cannot be made. Indirect measurements of

  3. Comment on Origin of Groundwater Discharge at Fall River Springs

    SciTech Connect

    Rose, T

    2006-10-20

    I'm writing at the request of the Pit River Tribe to offer my professional opinion as a geochemist regarding the origin of groundwater discharge at the Fall River Springs, Shasta Co., California. In 1997, I conducted a study of the large volume cold springs associated with the Cascade Volcanoes in northern California, in collaboration with one of my colleagues. This work was published as a Lawrence Livermore National Laboratory report (Davisson and Rose, 1997). The Fall River Springs emerge from the distal end of the Giant Crater Lava Field, a laterally extensive basalt flow that stretches from the southern flank of Medicine Lake Volcano southward for a distance of 40 km. Both Medicine Lake Volcano and the Giant Crater Lava Field have virtually no surface water drainages. Precipitation that falls in these areas is inferred to seep into fractures in the rock, where it is carried down gradient under the force of gravity. Mean annual precipitation rates on Medicine Lake Volcano and the Giant Crater Lava field are adequate to account for the {approx}1200 ft{sup 3}/sec discharge of the Fall River Springs. To evaluate the origin of the springs using geochemical methods, water samples were collected from the Fall River Springs and the Medicine Lake highlands and analyzed for oxygen and hydrogen isotope ratios. The isotope ratios measured for a groundwater sample are diagnostic of the average composition of the precipitation from which the water was derived. The isotope ratios of rain and snow also vary systematically with elevation, such that groundwater derived from recharge at higher elevations can be distinguished from that which originated at lower elevations. The stable isotope data for the Fall River Springs are consistent with groundwater recharge on the Medicine Lake Volcano and adjacent lava field. Mass balance calculations suggest that approximately half of the Fall River Springs flow is derived from the volcanic edifice. Rose and Davisson (1996) showed that the

  4. Hybrid Forecasting of Daily River Discharges Considering Autoregressive Heteroscedasticity

    NASA Astrophysics Data System (ADS)

    Szolgayová, Elena Peksová; Danačová, Michaela; Komorniková, Magda; Szolgay, Ján

    2017-06-01

    It is widely acknowledged that in the hydrological and meteorological communities, there is a continuing need to improve the quality of quantitative rainfall and river flow forecasts. A hybrid (combined deterministic-stochastic) modelling approach is proposed here that combines the advantages offered by modelling the system dynamics with a deterministic model and a deterministic forecasting error series with a data-driven model in parallel. Since the processes to be modelled are generally nonlinear and the model error series may exhibit nonstationarity and heteroscedasticity, GARCH-type nonlinear time series models are considered here. The fitting, forecasting and simulation performance of such models have to be explored on a case-by-case basis. The goal of this paper is to test and develop an appropriate methodology for model fitting and forecasting applicable for daily river discharge forecast error data from the GARCH family of time series models. We concentrated on verifying whether the use of a GARCH-type model is suitable for modelling and forecasting a hydrological model error time series on the Hron and Morava Rivers in Slovakia. For this purpose we verified the presence of heteroscedasticity in the simulation error series of the KLN multilinear flow routing model; then we fitted the GARCH-type models to the data and compared their fit with that of an ARMA - type model. We produced one-stepahead forecasts from the fitted models and again provided comparisons of the model's performance.

  5. 78 FR 23951 - Powder River Regional Coal Team Activities: Notice of Public Meeting in Casper, Wyoming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-23

    ... River Regional Coal Team (RCT) has scheduled a public meeting for June 19, 2013, to review coal management activities in the Powder River Coal Production Region. DATES: The RCT meeting will begin at 9 a.m... coal-related topics planned for the RCT meeting include: 1. Update on U.S. Geological Survey coal...

  6. Influence of wind and river discharge on the vertical exchange process in the Pearl River Estuary

    NASA Astrophysics Data System (ADS)

    Hong, B.; Peng, S.

    2016-02-01

    Vertical exchange process is controlled by the buoyancy input from river discharge and the momentum input by wind forcing. This study investigates the vertical exchange process in the Pearl River Estuary by using a 3-D numerical model. The vertical exchange time (VET) is used to quantify the magnitude of vertical exchange process in response to changing local wind and river discharge. During the dry season, it only takes about 2 days for the surface layer water mass being transported to the bottom layer. During the wet season, such transport will take more than 20 days in a large portion of the main channel. The water in the slope area can be well ventilated. Linear regression of VET indicates that water column stratification can be used to estimate the VET and up to 71% of the variance can be accounted. The estimation by using river runoff can only account for about 49% of the variance. The effects of wind speed and direction are investigated separately. Neither river runoff nor the stratification can properly predict the VET during the typical wet season. Further investigations are needed to reveal the dynamics of vertical exchange process and find out other factors that influence the VET during the wet season.

  7. Preliminary analysis for trends in selected water-quality characteristics, Powder River, Montana and Wyoming, water years 1952-85

    USGS Publications Warehouse

    Cary, L.E.

    1989-01-01

    Selected water-quality data from two streamflow-gaging stations on the Powder River, Montana and Wyoming, were statistically analyzed for trends using the seasonal Kendall test. Data for water years 1952-63 and 1975-85 from the Powder River near Locate, Montana, and water years 1967-68 and 1976-85 from the Powder River at Sussex, Wyoming, were analyzed. Data for the earlier period near Locate were discharge-weighted monthly mean values, whereas data for the late period near Locate and at Sussex were from periodic samples. For data from water years 1952-63 near Locate, increasing trends were detected in sodium and sodium-adsorption ratio; no trends were detected in specific conductance, hardness, non-carbonate hardness, alkalinity, dissolved solids, or sulfate. For data from water years 1975-85 near Locate, increasing trends were detected in specific conductance, sodium, sodium-adsorption ratio, and chloride; no trends were detected in hardness, noncarbonate hardness, alkalinity, dissolved solids, calcium, magnesium, potassium, or sulfate. At Sussex (water years 1967-68 and 1976-85), increasing trends were detected in sodium, sodium-adsorption ratio, and chloride, and a decreasing trend was detected in sulfate. No trends were detected in specific conductance, alkalinity, or dissolved solids. When the 1967-68 data were deleted and the analysis repeated for the 1976-85 data, only sodium-adsorption ratio displayed a significant (increasing) trend. Because the study was exploratory, causes and effects were not considered. The results might have been affected by sample size, number of seasons, heterogeneity, significance level, serial correlation, and data adjustment for changes in discharge. (USGS)

  8. Miocene Coral Skeleton Rare Earth Element Patterns Reflect River Discharge

    NASA Astrophysics Data System (ADS)

    Mertz-Kraus, R.; Brachert, T. C.; Jochum, K. P.

    2010-12-01

    Rare Earth Element (REE) patterns of modern coral skeletons usually reflect the REE composition of ambient seawater which is characterized by heavy REE enriched relative to light REE with NASC (North American Shale Composite) normalized La/Lu ratios of typically <0.4. The REE concentration in coral aragonite is enriched by 3 to 4 orders of magnitude compared to ambient seawater. Here we report trace element data including REE of coral skeletons of Late Miocene age (~9 Ma, Tortonian) from Crete (Eastern Mediterranean). Analyses were done using a 213 nm Nd:YAG laser coupled to an Element2 ICP-MS along the growth axis of the coral skeletons. The profiles show that Ba/Ca ratios have a seasonally induced pattern with high values around the winter months which are identified by δ18O analyses. REE/Ca ratios co-vary with Ba/Ca ratios. Since the Ba/Ca ratio is a proxy used to monitor river discharge, the co-variation suggests the REE/Ca ratio to be a proxy of comparable quality. NASC-normalized REE patterns of the Tortonian corals have negative Ce anomalies like modern corals. However, the Tortonian corals have REE patterns highly enriched in LREE with (La/Lu)N ratios of 4 to 30 which is 1 to 2 orders of magnitude higher compared to modern corals. Al concentrations are low (<10 ppm) and do not correlate with REE concentrations indicating an insignificant fraction of terrigenous material included in the skeleton. Applying distribution coefficients typical for modern corals, the REE composition of the Tortonian ambient water yields (La/Lu)N of about 2 to 16. This range can be explained by binary mixing of modern Eastern Mediterranean sea surface water ((La/Lu)N=0.35, sea surface salinity (SSS) ~38 ‰) with highly LREE-enriched river water ((La/Lu)N >3, salinity ~0.5 ‰) transporting suspended and colloid phases, also highly enriched, especially in LREE, at a ratio of ~9 (seawater):1 (river water). The river water component is considered because paleoenvironmental

  9. Surface modification of tungsten carbide by electrical discharge coating (EDC) using a titanium powder suspension

    NASA Astrophysics Data System (ADS)

    Janmanee, Pichai; Muttamara, Apiwat

    2012-07-01

    Surface modification by a titanium coating layer onto a tungsten carbide surface by electrical discharge coating (EDC) was studied by considering a titanium coating modification as well as the completeness of the tungsten carbide surface. This was carried out by electrical discharge machining (EDM). The tungsten carbide material was produced using a fluid dielectric oil, which was mixed with titanium powder. The current and duty cycles were varied resulting in a change in the titanium coating layer thickness. Also, an analysis of the chemical composition using energy dispersive spectroscopy (EDS) revealed that a titanium coating layer was formed causing the hardness of the titanium surface to be close to that of tungsten carbide. The completeness of the surface was evaluated using scanning electron microscopy (SEM) and a small number of microcracks were found on the surface since the microcracks were filled and substituted by titanium powder and carbon (a hydrocarbon) that decomposed from the dielectric that acted as a combiner (TiC). Also, the high concentration of carbon increased the amount of Ti and C combination and TiC was formed, which enhanced the surface hardness of the coated layer to 1750 HV. The surface roughness of the coated layer decreased and this reduced the formation of microcracks on the surface workpiece.

  10. Zero discharge organic coatings, powder paint - UV curable paint - E-coat. Volume 1. Final report, June 1993-June 1995

    SciTech Connect

    Leal, J.; Martin, D.R.; Spadafora, S.J.; Eng, A.T.; Stark, H.

    1995-06-01

    Zero Discharge Organic Coatings project developed powder paint, Ultraviolet (UV) curable paint, and electro- coating (E-coat) paint for military Applications. These technologies offer potential for high performance coatings with little or no volatile organic compound (VOC) emissions or hazardous waste generation. The ZDOC project focused on formulating non-toxic corrosion inhibitors into these coating technologies, and the applications development of powder coatings. Non-toxic replacements for traditional lead and chromate inhibitors were selected based on a previous NAWCADWAR investigation. Once incorporated, the performance of the coatings with and without inhibitors was compared. Also, the protective mechanisms of these inhibitors were studied. The applications development for powder coatings analyzed technologies to allow powder coating of non-conductive substrates and evaluated the use of IR energy to cure powder coatings. Inhibitors were successfully incorporated into electrocoatings and powder coatings, however corrosion performance results varied with coating formulation.

  11. Effects of river discharge on abundance and instantaneous growth of age-0 carpsuckers in the Oconee River, Georgia, USA

    USGS Publications Warehouse

    Peterson, Ronald C.; Jennings, C.A.

    2007-01-01

    The Oconee River in middle Georgia, U.S.A., has been regulated by the Sinclair Dam since 1953. Since then, the habitat of the lower Oconee River has been altered and the river has become more incised. The altered environmental conditions of the Oconee River may limit the success of various fish populations. Some obligate riverine fishes may be good indicator species for assessing river system integrity because they are intolerant to unfavourable conditions. For example, many sucker species require clean gravel for feeding and reproduction. Further, age-0 fishes are more vulnerable than adults to flow alterations because of their limited ability to react to such conditions. In this study, we investigated the relationship between abundance and growth of age-0 carpsuckers to river discharge in the Oconee River. A beach seine was used to collect age-0 carpsuckers (Carpiodes spp.) from littoral zones of the lower Oconee River from May through July of 1995 to 2001. Regression models were used to assess whether 12 river discharge categories (e.g. peak, low, seasonal flows) influenced age-0 carpsucker abundance or instantaneous growth. Our analysis indicated that abundance of age-0 carpsuckers was significantly negatively related to number of days river discharge was >85 m3 s-1(r2=0.61, p=0.04). Estimates of instantaneous growth ranged from 0.10 to 0.90. Instantaneous growth rates were significantly positively related to summer river discharge (r2=0.95, p<0.01). These results suggest that (1) moderate flows during spawning and rearing are important for producing strong-year classes of carpsuckers, and (2) river discharge is variable among years, with suitable flows for strong year-classes of carpsuckers occurring every few years. River management should attempt to regulate river discharge to simulate historic flows typical for the region when possible. Such an approach is best achieved when regional climatic conditions are considered.

  12. On the value of satellite-based river discharge and river flood data

    NASA Astrophysics Data System (ADS)

    Kettner, A. J.; Brakenridge, R.; van Praag, E.; Borrero, S.; Slayback, D. A.; Young, C.; Cohen, S.; Prades, L.; de Groeve, T.

    2015-12-01

    Flooding is the most common natural hazard worldwide. According to the World Resources Institute, floods impact 21 million people every year and affect the global GDP by $96 billion. Providing accurate flood maps in near-real time (NRT) is critical to their utility to first responders. Also, in times of flooding, river gauging stations on location, if any, are of less use to monitor stage height as an approximation for water surface area, as often the stations themselves get washed out or peak water levels reach much beyond their design measuring capacity. In a joint effort with NASA Goddard Space Flight Center, the European Commission Joint Research Centre and the University of Alabama, the Dartmouth Flood Observatory (DFO) measures NRT: 1) river discharges, and 2) water inundation extents, both with a global coverage on a daily basis. Satellite-based passive microwave sensors and hydrological modeling are utilized to establish 'remote-sensing based discharge stations'. Once calibrated, daily discharge time series span from 1998 to the present. Also, the two MODIS instruments aboard the NASA Terra and Aqua satellites provide daily floodplain inundation extent with global coverage at a spatial resolution of 250m. DFO's mission is to provide easy access to NRT river and flood data products. Apart from the DFO web portal, several water extent products can be ingested by utilizing a Web Map Service (WMS), such as is established with for Latin America and the Caribbean (LAC) region through the GeoSUR program portal. This effort includes implementing over 100 satellite discharge stations showing in NRT if a river is flooding, normal, or in low flow. New collaborative efforts have resulted in flood hazard maps which display flood extent as well as exceedance probabilities. The record length of our sensors allows mapping the 1.5 year, 5 year and 25 year flood extent. These can provide key information to water management and disaster response entities.

  13. Historical Changes in River Discharge in the Lower Columbia River: Impacts on River Stage, Tidal Range and Salmonid Habitat

    NASA Astrophysics Data System (ADS)

    Kukulka, T.; Jay, D. A.

    2001-12-01

    Juvenile salmonid access to favorable shallow water habitat in a tidal river and estuary is a function of river stage, tidal range, and the system's distribution of bed elevation. In this study, we investigate how historical changes in Columbia River discharge, due to climatic variability and flow regulation, affect river stage, tidal range, and salmonid access to shallow-water habitat in the lower Columbia River. Tidal height data collected (1980-2001) at gauging stations below Bonneville Dam (230 km from the ocean) are filtered to retrieve time-series of fluctuations in river stage, diurnal and semi-diurnal amplitude, overtides and tidal range. It is necessary to design a new filter bank, optimized with respect to time-frequency resolution, in order to capture the relevant physics of the non-stationary riverine-tidal processes. Tidal range and tidal amplitudes of the major tidal constituents are shown to have an approximately negative-exponential dependence on upriver distance and the square root of river flow. The river stage varies linearly with river flow to the first order. These results are consistent with solutions of the linearized St. Venant equations. Further, the results imply the division of the Lower Columbia River with respect to tidal damping and stage-flow dependency into fluvial and estuarine regimes. Stage and tidal range are more strongly related to river discharge in the fluvial than in the estuarine regime. The interface between the two regimes lies in the energy minimum region, roughly 50 km from the ocean, where dissipation is weak and about equally divided between tides and river flow. With these results and hypsometeric data, scenarios of historical flow variability and their impacts on shallow-water habitat access are reconstructed. We compare: a) tides during years with low-flow to those during years having strong freshets, and b) tides under highly regulated flows with those that would have prevailed without regulation. Because tides

  14. Modelling the fate of the Tijuana River discharge plume

    NASA Astrophysics Data System (ADS)

    van Ormondt, M.; Terrill, E.; Hibler, L. F.; van Dongeren, A. R.

    2010-12-01

    After rainfall events, the Tijuana River discharges excess runoff into the ocean in a highly turbid plume. The runoff waters contain large suspended solids concentrations, as well as high levels of toxic contaminants, bacteria, and hepatitis and enteroviruses. Public health hazards posed by the effluent often result in beach closures for several kilometers northward along the U.S. shoreline. A Delft3D model has been set up to predict the fate of the Tijuana River plume. The model takes into account the effects of tides, wind, waves, salinity, and temperature stratification. Heat exchange with the atmosphere is also included. The model consists of a relatively coarse outer domain and a high-resolution surf zone domain that are coupled with Domain Decomposition. The offshore boundary conditions are obtained from the larger NCOM SoCal model (operated by the US Navy) that spans the entire Southern California Bight. A number of discharge events are investigated, in which model results are validated against a wide range of field measurements in the San Diego Bight. These include HF Radar surface currents, REMUS tracks, drifter deployments, satellite imagery, as well as current and temperature profile measurements at a number of locations. The model is able to reproduce the observed current and temperature patterns reasonably well. Under calm conditions, the model results suggest that the hydrodynamics in the San Diego Bight are largely governed by internal waves. During rainfall events, which are typically accompanied by strong winds and high waves, wind and wave driven currents become dominant. An analysis will be made of what conditions determine the trapping and mixing of the plume inside the surfzone and/or the propagation of the plume through the breakers and onto the coastal shelf. The model is now also running in operational mode. Three day forecasts are made every 24 hours. This study was funded by the Office of Naval Research.

  15. Downstream ecosystem responses to middle reach regulation of river discharge in the Heihe River Basin, China

    NASA Astrophysics Data System (ADS)

    Zhao, Yan; Wei, Yongping; Li, Shoubo; Wu, Bingfang

    2016-11-01

    Understanding the oasis ecosystem responses to upstream regulation is a challenge for catchment management in the context of ecological restoration. This empirical study aimed to understand how oasis ecosystems, including water, natural vegetation and cultivated land, responded to the implementation of the Ecological Water Diversion Project (EWDP) in the Heihe River in China. The annual Landsat images from 1987 to 2015 were firstly used to characterize the spatial extent, frequency index and fractional coverage (for vegetation only) of these three oasis ecosystems and their relationships with hydrological (river discharge) and climatic variables (regional temperature and precipitation) were explored with linear regression models. The results show that river regulation of the middle reaches identified by the discharge allocation to the downstream basin experiences three stages, namely decreasing inflow (1987-1999), increasing inflow (2000-2007) and relative stable inflow (2008-2015). Both the current and previous years' combined inflow determines the surface area of the terminal lake (R2 = 0.841). Temperature has the most significant role in determining broad vegetation distribution, whereas hydrological variables had a significant effect only in near-river-channel regions. Agricultural development since the execution of the EWDP might have curtailed further vegetation recovery. These findings are important for the catchment managers' decisions about future water allocation plans.

  16. Modelling the impact of wind stress and river discharge on Danshuei River plume

    USGS Publications Warehouse

    Liu, W.-C.; Chen, W.-B.; Cheng, R.T.; Hsu, M.-H.

    2008-01-01

    A three-dimensional, time-dependent, baroclinic, hydrodynamic and salinity model, UnTRIM, was performed and applied to the Danshuei River estuarine system and adjacent coastal sea in northern Taiwan. The model forcing functions consist of tidal elevations along the open boundaries and freshwater inflows from the main stream and major tributaries in the Danshuei River estuarine system. The bottom friction coefficient was adjusted to achieve model calibration and verification in model simulations of barotropic and baroclinic flows. The turbulent diffusivities were ascertained through comparison of simulated salinity time series with observations. The model simulation results are in qualitative agreement with the available field data. The validated model was then used to investigate the influence of wind stress and freshwater discharge on Dasnhuei River plume. As the absence of wind stress, the anticyclonic circulation is prevailed along the north to west coast. The model results reveal when winds are downwelling-favorable, the surface low-salinity waters are flushed out and move to southwest coast. Conversely, large amounts of low-salinity water flushed out the Danshuei River mouth during upwelling-favorable winds, as the buoyancy-driven circulation is reversed. Wind stress and freshwater discharge are shown to control the plume structure. ?? 2007 Elsevier Inc. All rights reserved.

  17. Conceptual model of the uppermost principal aquifer systems in the Williston and Powder River structural basins, United States and Canada

    USGS Publications Warehouse

    Long, Andrew J.; Aurand, Katherine R.; Bednar, Jennifer M.; Davis, Kyle W.; McKaskey, Jonathan D.R.G.; Thamke, Joanna N.

    2014-01-01

    includes parts of Montana, North Dakota, South Dakota, and Wyoming in the United States and Manitoba and Saskatchewan in Canada. The glacial aquifer system is contained within glacial drift consisting primarily of till, with smaller amounts of glacial outwash sand and gravel deposits. The lower Tertiary and Upper Cretaceous aquifer systems are contained within several formations of the Tertiary and Cretaceous geologic systems, which are hydraulically separated from underlying aquifers by a basal confining unit. The lower Tertiary and Upper Cretaceous aquifer systems each were divided into three hydrogeologic units that correspond to one or more lithostratigraphic units. The period prior to 1960 is defined as the predevelopment period when little groundwater was extracted. From 1960 through 1990, numerous flowing wells were installed near the Yellowstone, Little Missouri and Knife Rivers, resulting in local groundwater declines. Recently developed technologies for the extraction of petroleum resources, which largely have been applied in the study area since about 2005, require millions of gallons of water for construction of each well, with additional water needed for long-term operation; therefore, the potential for an increase in groundwater extraction is high. In this study, groundwater recharge and discharge components were estimated for the period 1981–2005. Groundwater recharge primarily occurs from infiltration of rainfall and snowmelt (precipitation recharge) and infiltration of streams into the ground (stream infiltration). Total estimated recharge to the Williston and Powder River control volumes is 4,560 and 1,500 cubic feet per second, respectively. Estimated precipitation recharge is 26 and 15 percent of total recharge for the Williston and Powder River control volumes, respectively. Estimated stream infiltration is 71 and 80 percent of total recharge for the Williston and Powder River control volumes, respectively. Groundwater discharge primarily is to

  18. Predictability of current and future multi-river discharges: Ganges, Brahmaputra, Yangtze, Blue Nile, and Murray-Darling rivers

    NASA Astrophysics Data System (ADS)

    Jian, Jun

    2007-12-01

    Determining river discharge is of critical importance to many societies as they struggle with fresh water supply and risk of flooding. In Bangladesh, floods occur almost every year but with sufficient irregularity to have adverse social and economical consequences. Important goals are to predict the discharge to be used for the optimization of agricultural practices, disaster mitigation and water resource management. The aim of this study is to determine the predictability of river discharge in a number of major rivers on time scale varying from weeks to a century. We investigated predictability considering relationship between SST and discharge. Next, we consider IPCC model projections of river discharge while the models are statistically adjusted against observed discharges. In this study, we consider five rivers, the Ganges, the Brahmaputra, the Yangtze, the Blue Nile, and the Murray-Darling Rivers. On seasonal time scales, statistically significant correlations are found between mean monthly equatorial Pacific sea surface temperature (SST) and the summer Ganges discharge with lead times of 2-3 months due to oscillations of the El Nino-Southern Oscillation (ENSO) phenomena. In addition, there are strong correlations in the southwest and northeast Pacific. These, too, appear to be tied to the ENSO cycle. The Brahmaputra discharge, on the other hand, shows somewhat weaker relationships with tropical SST. Strong lagged correlations relationships are found with SST in the Bay of Bengal but these are the result of very warm SSTs and exceptional Brahmaputra discharge during the summer of 1998. When this year is removed from the time series, relationships weaken everywhere except in the northwestern Pacific for the June discharge and in areas of the central Pacific straddling the equator for the July discharge. The relationships are relative strong, but they are persistent from month to month and suggest that two different and sequential factors influence Brahmaputra

  19. Upstream Satellite Remote Sensing for River Discharge Forecasting: Application to Major Rivers in South Asia

    NASA Astrophysics Data System (ADS)

    Hopson, Thomas; Hirpa, Feyera; Brakenridge, G. Robert; Webster, Peter J.; De Groeve, Tom; Gebremichael, Mekonnen; Restrepo, Pedro

    2013-04-01

    In this work we demonstrate the utility of satellite remote sensing for river discharge nowcasting and forecasting for two major rivers, the Ganges and Brahmaputra, in southern Asia. Passive microwave sensing of the river and floodplain at more than twenty locations upstream of Hardinge Bridge (Ganges) and Bahadurabad (Brahmaputra) gauging stations are used to: 1) evaluate their use in producing stand-alone river flow nowcasts, and forecasts at 1-15 days lead time; and 2) how they can be combined to improve the skill of an ongoing ensemble weather forecast-based flood forecasting system. The pattern of correlation between upstream satellite data and in situ observations of downstream discharge is used to estimate wave propagation time. This pattern of correlation is combined with a cross-validation method to select the satellite sites that produce the most accurate river discharge estimates in a lagged regression model. The results show that the well-correlated satellite-derived flow (SDF) signals were able to detect the propagation of a river flow wave along both river channels. The daily river discharge (contemporaneous) nowcast produced from the upstream SDFs could be used to provide missing data estimates given its Nash-Sutcliffe coefficient of 0.8 for both rivers; and forecasts have considerably better skill than autoregressive moving-average (ARMA) model beyond 3-day lead time for Brahmaputra. Due to the expected better accuracy of the SDF for detecting large flows, the forecast error is found to be lower for high flows compared to low flows. Overall, we conclude that satellite-based flow estimates are a useful source of dynamical surface water information in data-scarce regions and that they could be used for model calibration and data assimilation purposes in near-time hydrologic forecast applications. The paper concludes by explore the utility of the SDF's in improving the skill of the existing Climate Forecasting Applications for Bangladesh (CFAB

  20. Trans-Himalayan water contributions to river discharge

    NASA Astrophysics Data System (ADS)

    Andermann, Christoff; Stieglitz, Thomas; Schuessler, Jan A.; Parajouli, Binod

    2017-04-01

    Hydrological processes in high mountains are not well understood. Groundwater is commonly considered to be of little importance in the mountain water balance, while direct runoff, snow and ice melt are thought to be the principal hydrological buffer. We present new insights into hydrological fluxes between major reservoirs in a trans-Himalayan catchment. The study area is the Kali Gandaki catchment, rising in the dry Tibetan interior, carving through the high Himalayas and draining the full width of the foothills to the Ganges foreland. The catchment has a well-defined monsoon climate, with pronounced annual wet and dry seasons and a clear separation of wind- and leeward regions. We have sampled the main river and its tributaries as well as several springs during the four hydrological seasons (winter, pre-monsoon, monsoon, post-monsoon). We have measured major element abundances as well as 222Rn in situ, as a tracer for groundwater contribution. These measurements are placed in a context of topographic analyses as well as continuous discharge and precipitation measurements. Furthermore, we have equipped two sites with continuous water samplers, sampling over > 4 monsoon seasons, allowing us to resolve the seasonal hydrological dynamic range on a very high temporal resolution. Chemical fluxes vary spatially over several orders of magnitude, showing a systematic downstream dilution trend for most major elements during all hydrological seasons. High initial concentrations derive from evaporite deposits in the uppermost part of the catchment, constituting a large scale, natural salt tracer experiment. The well-defined decline of solute concentrations along the main river, paired with constraints on the composition of lateral water inputs downstream allow the calculation of the spatial distribution of additional hydrological fluxes, by applying end member mixing modeling. Continuous river stage and bulk dissolved load (electrical conductivity) monitoring depict well

  1. Sediment transport and effective discharge of the North Platte, South Platte, and Platte Rivers in Nebraska

    USGS Publications Warehouse

    Kircher, J.E.

    1981-01-01

    Sediment discharge was computed for four locations along the North Platte, South Platte, and the Platte Rivers between North Platte and Grand Island, Nebraska in order to determine the effective discharge. The total-sediment discharge was computed by the Colby method and modified Einstein method so that comparisons could be made with the measured total-sediment discharge. The results agreed closely. The Colby method is the simplest and most convenient to use. The mean annual total-sediment discharge for the four sites investigated ranged from 150 tons per day for the South Platte River at North Platte to 1,260 tons per day for the Platte River near Grand Island. The effective discharge at the sites ranged from 41 to 158 cubic meters per second. The probability of the effective discharge being equaled or exceeded ranged from 1 to 30 percent for the four sites. (USGS)

  2. Climatic and anthropogenic factors affecting river discharge to the global ocean, 1951-2000

    USGS Publications Warehouse

    Milliman, John D.; Farnsworth, K.L.; Jones, P.D.; Xu, K.H.; Smith, L.C.

    2008-01-01

    During the last half of the 20th century, cumulative annual discharge from 137 representative rivers (watershed areas ranging from 0.3 to 6300 ?? 103??km2) to the global ocean remained constant, although annual discharge from about one-third of these rivers changed by more than 30%. Discharge trends for many rivers reflected mostly changes in precipitation, primarily in response to short- and longer-term atmospheric-oceanic signals; with the notable exception of the Parana, Mississippi, Niger and Cunene rivers, few of these "normal" rivers experienced significant changes in either discharge or precipitation. Cumulative discharge from many mid-latitude rivers, in contrast, decreased by 60%, reflecting in large part impacts due to damming, irrigation and interbasin water transfers. A number of high-latitude and high-altitude rivers experienced increased discharge despite generally declining precipitation. Poorly constrained meteorological and hydrological data do not seem to explain fully these "excess" rivers; changed seasonality in discharge, decreased storage and/or decreased evapotranspiration also may play important roles. ?? 2008 Elsevier B.V. All rights reserved.

  3. Fish assemblage shifts in the Powder River of Wyoming: an unregulated prairie river system previously considered to be relatively pristine.

    USGS Publications Warehouse

    Senecal, Anna C.; Walters, Annika W.; Hubert, Wayne A.

    2016-01-01

    Wyoming’s Powder River is considered an example of a pristine prairie river system. While the river hosts a largely native fish assemblage and remains unimpounded over its 1,146-km course to the Yellowstone River confluence, the hydrologic regime has been altered through water diversion for agriculture and natural gas extraction and there has been limited study of fish assemblage structure. We analyzed fish data collected from the mainstem Powder River in Wyoming between 1896 and 2008. Shifts in presence/absence and relative abundance of fish species, as well as fish assemblage composition, were assessed among historical and recent samples. The recent Powder River fish assemblage was characterized by increased relative abundances of sand shiner Notropis stramineus and plains killifish Fundulus zebrinus, and decreases in sturgeon chub Macrhybopsis gelida. Shifts in fish species relative abundance are linked to their reproductive ecology with species with adhesive eggs generally increasing in relative abundance while those with buoyant drifting eggs are decreasing. Assemblage shifts could be the result of landscape level changes, such as the loss of extreme high and low flow events and changing land use practices.

  4. Effect of glow discharge sintering in the properties of a composite material fabricated by powder metallurgy

    NASA Astrophysics Data System (ADS)

    Cardenas, A.; Pineda, Y.; Sarmiento Santos, A.; Vera, E.

    2016-02-01

    Composite samples of 316 stainless steel and SiC were produced by powder metallurgy. Starting materials were mixed in different proportions and compacted to 700MPa. Sintering stage was performed by abnormal glow discharge plasma with direct current in an inert atmosphere of argon. The process was conducted at a temperature of 1200°C±5°C with a heating rate of 100°C/min. This work shows, the effectiveness of plasma sintering process to generate the first contacts between particles and to reduce vacancies. This fact is confirmed by comparing green and sintered density of the material. The results of porosity show a decrease after plasma sintering. Wear tests showed the wear mechanisms, noting that at higher SiC contents, the wear resistance decreases due to poor matrix-reinforcement interaction and by the porosity presence which causes matrix-reinforcement sliding.

  5. Water-quality characteristics, including sodium-adsorption ratios, for four sites in the Powder River drainage basin, Wyoming and Montana, water years 2001-2004

    USGS Publications Warehouse

    Clark, Melanie L.; Mason, Jon P.

    2006-01-01

    The U.S. Geological Survey, in cooperation with the Wyoming Department of Environmental Quality, monitors streams throughout the Powder River structural basin in Wyoming and parts of Montana for potential effects of coalbed natural gas development. Specific conductance and sodium-adsorption ratios may be larger in coalbed waters than in stream waters that may receive the discharge waters. Therefore, continuous water-quality instruments for specific conductance were installed and discrete water-quality samples were collected to characterize water quality during water years 2001-2004 at four sites in the Powder River drainage basin: Powder River at Sussex, Wyoming; Crazy Woman Creek near Arvada, Wyoming; Clear Creek near Arvada, Wyoming; and Powder River at Moorhead, Montana. During water years 2001-2004, the median specific conductance of 2,270 microsiemens per centimeter at 25 degrees Celsius (?S/cm) in discrete samples from the Powder River at Sussex, Wyoming, was larger than the median specific conductance of 1,930 ?S/cm in discrete samples collected downstream from the Powder River at Moorhead, Montana. The median specific conductance was smallest in discrete samples from Clear Creek (1,180 ?S/cm), which has a dilution effect on the specific conductance for the Powder River at Moorhead, Montana. The daily mean specific conductance from continuous water-quality instruments during the irrigation season showed the same spatial pattern as specific conductance values for the discrete samples. Dissolved sodium, sodium-adsorption ratios, and dissolved solids generally showed the same spatial pattern as specific conductance. The largest median sodium concentration (274 milligrams per liter) and the largest range of sodium-adsorption ratios (3.7 to 21) were measured in discrete samples from the Powder River at Sussex, Wyoming. Median concentrations of sodium and sodium-adsorption ratios were substantially smaller in Crazy Woman Creek and Clear Creek, which tend to

  6. Impact of beaver ponds on river discharge and sediment deposition along the Chevral River, Ardennes, Belgium

    NASA Astrophysics Data System (ADS)

    Nyssen, Jan; Frankl, Amaury; Pontzeele, Jolien; De Visscher, Maarten; Billi, Paolo

    2013-04-01

    With the recovery of the European beaver (Castor fiber) and their capacity to engineer fluvial landscapes, questions arise as to how they influence river discharge and sediment transport. The Chevral river (Ardennes, Belgium) contains two beaver dam sequences which appeared in 2004 and count now about 30 dams. Flow discharges and sediment fluxes were measured at the in- and outflow of each dam sequence. Volumes of sediment deposited behind the dams were measured. Between 2004 and 2011, peak flows were topped off, and the magnitude of extreme events decreased. 1710 m³ of sediment were deposited behind the beaver dams, with an average sediment thickness of 25 cm. The thickness of the sediment layer is related to the area of the beaver ponds. Along the stream, beaver pond sediment thickness displayed a sinusoidal deposition pattern, in which ponds with thick sediment layers were preceded by a series of ponds with thinner sediment layers. A downstream textural coarsening in the dam sequences was also observed, probably due to dam failures subsequent to surges. Differences in sediment flux between the in- and outflow at the beaver pond sequence were related to the river hydrograph, with deposition taking place during the rising limbs and slight erosion during the falling limbs. The seven-year-old sequences have filtered 190 tons of sediment out of the Chevral river, which is of the same order of magnitude as the 374 tons measured in pond deposits, with the difference between the values corresponding to beaver excavations (60 tons), inflow from small tributaries, and runoff from the valley flanks. Hydrogeomorphic effects of C. fiber and C. canadensis activity are similar in magnitude. The detailed analysis of changes to hydrology in beaver pond sequences confirms the potential of beavers to contribute to river and wetland restoration and catchment management.

  7. High spin-dependent tunneling magnetoresistance in magnetite powders made by arc-discharge

    NASA Astrophysics Data System (ADS)

    Prakash, T.; Williams, G. V. M.; Kennedy, J.; Rubanov, S.

    2016-09-01

    We report the successful synthesis of ferrimagnetic magnetite powders made using an arc-discharge method in a partial oxygen atmosphere. X-ray and electron diffraction measurements show that the powders also contain some antiferromagnetic hematite and a small amount of FeO and Fe that has not oxidized. The Raman data show that there is a small fraction of ferrimagnetic maghemite that cannot be seen in the x-ray diffraction data. There is a wide particle size distribution where there are nanoparticles as small as 7 nm, larger faceted nanoparticles, and particles that are up to 25 μm in diameter. The saturation magnetization at high magnetic fields is ˜74% of that found in the bulk magnetite, where the lower value is due to the presence of some antiferromagnetic hematite. The temperature dependence of the saturation magnetization changes at the Verwey transition temperature, and it has a power low dependence with an exponent of 3/2 at low temperatures and 2.23 at high temperatures above the Verwey transition temperature. Electronic transport measurements were made on a cold-pressed pellet and the electrical resistance had an exponential dependence on temperature that may be due to electrostatic charging during tunneling between small nanoparticles. A large magnetoresistance from spin-dependent tunneling between the magnetite particles was observed that reached -9.5% at 120 K and 8 T.

  8. Terrace aggradation during the 1978 flood on Powder River, Montana, USA

    USGS Publications Warehouse

    Moody, J.A.; Meade, R.H.

    2008-01-01

    Flood processes no longer actively increase the planform area of terraces. Instead, lateral erosion decreases the area. However, infrequent extreme floods continue episodic aggradation of terraces surfaces. We quantify this type of evolution of terraces by an extreme flood in May 1978 on Powder River in southeastern Montana. Within an 89-km study reach of the river, we (1) determine a sediment budget for each geomorphic feature, (2) interpret the stratigraphy of the newly deposited sediment, and (3) discuss the essential role of vegetation in the depositional processes. Peak flood discharge was about 930??m3 s- 1, which lasted about eight??days. During this time, the flood transported 8.2??million tons of sediment into and 4.5??million tons out of the study reach. The masses of sediment transferred between features or eroded from one feature and redeposited on the same feature exceeded the mass transported out of the reach. The flood inundated the floodplain and some of the remnants of two terraces along the river. Lateral erosion decreased the planform area of the lower of the two terraces (~ 2.7??m above the riverbed) by 3.2% and that of the higher terrace (~ 3.5??m above the riverbed) by 4.1%. However, overbank aggradation, on average, raised the lower terrace by 0.16??m and the higher terrace by 0.063??m. Vegetation controlled the type, thickness, and stratigraphy of the aggradation on terrace surfaces. Two characteristic overbank deposits were common: coarsening-upward sequences and lee dunes. Grass caused the deposition of the coarsening-upward sequences, which had 0.02 to 0.07??m of mud at the base, and in some cases, the deposits coarsened upwards to coarse sand on the top. Lee dunes, composed of fine and very fine sand, were deposited in the wake zone downstream from the trees. The characteristic morphology of the dunes can be used to estimate some flood variables such as suspended-sediment particle size, minimum depth, and critical shear velocity

  9. Assessment of coal geology, resources, and reserves in the northern Wyoming Powder River Basin

    USGS Publications Warehouse

    Scott, David C.; Haacke, Jon E.; Osmonson, Lee M.; Luppens, James A.; Pierce, Paul E.; Rohrbacher, Timothy J.

    2010-01-01

    The abundance of new borehole data from recent coal bed natural gas development in the Powder River Basin was utilized by the U.S. Geological Survey for the most comprehensive evaluation to date of coal resources and reserves in the Northern Wyoming Powder River Basin assessment area. It is the second area within the Powder River Basin to be assessed as part of a regional coal assessment program; the first was an evaluation of coal resources and reserves in the Gillette coal field, adjacent to and south of the Northern Wyoming Powder River Basin assessment area. There are no active coal mines in the Northern Wyoming Powder River Basin assessment area at present. However, more than 100 million short tons of coal were produced from the Sheridan coal field between the years 1887 and 2000, which represents most of the coal production within the northwestern part of the Northern Wyoming Powder River Basin assessment area. A total of 33 coal beds were identified during the present study, 24 of which were modeled and evaluated to determine in-place coal resources. Given current technology, economic factors, and restrictions to mining, seven of the beds were evaluated for potential reserves. The restrictions included railroads, a Federal interstate highway, urban areas, and alluvial valley floors. Other restrictions, such as depth, thickness of coal beds, mined-out areas, and areas of burned coal, were also considered. The total original coal resource in the Northern Wyoming Powder River Basin assessment area for all 24 coal beds assessed, with no restrictions applied, was calculated to be 285 billion short tons. Available coal resources, which are part of the original coal resource that is accessible for potential mine development after subtracting all restrictions, are about 263 billion short tons (92.3 percent of the original coal resource). Recoverable coal, which is that portion of available coal remaining after subtracting mining and processing losses, was determined

  10. Ecological assessment of streams in the Powder River Structural Basin, Wyoming and Montana, 2005-06

    USGS Publications Warehouse

    Peterson, D.A.; Wright, P.R.; Edwards, G.P.; Hargett, E.G.; Feldman, D.L.; Zumberge, J.R.; Dey, Paul

    2009-01-01

    Energy and mineral development, particularly coalbed natural gas development, is proceeding at a rapid pace in the Powder River Structural Basin (PRB) in northeastern Wyoming. Concerns about the potential effects of development led to formation of an interagency working group of primarily Federal and State agencies to address these issues in the PRB in Wyoming and in Montana where similar types of resources exist but are largely undeveloped. Under the direction of the interagency working group, an ecological assessment of streams in the PRB was initiated to determine the current status (2005–06) and to establish a baseline for future monitoring.The ecological assessment components include assessment of stream habitat and riparian zones as well as assessments of macroinvertebrate, algal, and fish communities. All of the components were sampled at 47 sites in the PRB during 2005. A reduced set of components, consisting primarily of macroinvertebrate and fish community assessments, was sampled in 2006. Related ecological data, such as habitat and fish community data collected from selected sites in 2004, also are included in this report.The stream habitat assessment included measurement of channel features, substrate size and embeddedness, riparian vegetation, and reachwide characteristics. The width-to-depth ratio (bankfull width/bankfull depth) tended to be higher at sites on the main-stem Powder River than at sites on the main-stem Tongue River and at sites on tributary streams. The streambed substrate particle size was largest at sites on the main-stem Tongue River and smallest at sites on small tributary streams such as Squirrel Creek and Otter Creek. Total vegetative cover at the ground level, understory, and canopy layers ranged from less than 40 percent at a few sites to more than 90 percent at many of the sites. A bank-stability index indicated that sites in the Tongue River drainage were less at risk of bank failure than sites on the main-stem Powder River

  11. Modeling the impact of river discharge and wind on the hypoxia off Yangtze Estuary

    NASA Astrophysics Data System (ADS)

    Zheng, Jingjing; Gao, Shan; Liu, Guimei; Wang, Hui; Zhu, Xueming

    2016-12-01

    The phenomenon of low dissolved oxygen (known as hypoxia) in a coastal ocean system is closely related to a combination of anthropogenic and natural factors. Marine hypoxia occurs in the Yangtze Estuary, China, with high frequency and long persistence. It is related primarily to organic and nutrient enrichment influenced by river discharges and physical factors, such as water mixing. In this paper, a three-dimensional hydrodynamic model was coupled to a biological model to simulate and analyze the ecological system of the East China Sea. By comparing with the observation data, the model results can reasonably capture the physical and biochemical dynamics of the Yangtze Estuary. In addition, the sensitive experiments were also used to examine the role of physical forcing (river discharge, wind speed, wind direction) in controlling hypoxia in waters adjacent to the Yangtze Estuary. The results showed that the wind field and river discharge have significant impact on the hypoxia off the Yangtze Estuary. The seasonal cycle of hypoxia was relatively insensitive to synoptic variability in the river discharge, but integrated hypoxic areas were sensitive to the whole magnitude of river discharge. Increasing the river discharge was shown to increase hypoxic areas, while decreasing the river discharge tended to decrease hypoxic areas. The variations of wind speed and direction had a great impact on the integrated hypoxic areas.

  12. Improved error estimates of a discharge algorithm for remotely sensed river measurements: Test cases on Sacramento and Garonne Rivers

    NASA Astrophysics Data System (ADS)

    Yoon, Yeosang; Garambois, Pierre-André; Paiva, Rodrigo C. D.; Durand, Michael; Roux, Hélène; Beighley, Edward

    2016-01-01

    We present an improvement to a previously presented algorithm that used a Bayesian Markov Chain Monte Carlo method for estimating river discharge from remotely sensed observations of river height, width, and slope. We also present an error budget for discharge calculations from the algorithm. The algorithm may be utilized by the upcoming Surface Water and Ocean Topography (SWOT) mission. We present a detailed evaluation of the method using synthetic SWOT-like observations (i.e., SWOT and AirSWOT, an airborne version of SWOT). The algorithm is evaluated using simulated AirSWOT observations over the Sacramento and Garonne Rivers that have differing hydraulic characteristics. The algorithm is also explored using SWOT observations over the Sacramento River. SWOT and AirSWOT height, width, and slope observations are simulated by corrupting the "true" hydraulic modeling results with instrument error. Algorithm discharge root mean square error (RMSE) was 9% for the Sacramento River and 15% for the Garonne River for the AirSWOT case using expected observation error. The discharge uncertainty calculated from Manning's equation was 16.2% and 17.1%, respectively. For the SWOT scenario, the RMSE and uncertainty of the discharge estimate for the Sacramento River were 15% and 16.2%, respectively. A method based on the Kalman filter to correct errors of discharge estimates was shown to improve algorithm performance. From the error budget, the primary source of uncertainty was the a priori uncertainty of bathymetry and roughness parameters. Sensitivity to measurement errors was found to be a function of river characteristics. For example, Steeper Garonne River is less sensitive to slope errors than the flatter Sacramento River.

  13. Seasonal forecasting of discharge for the Raccoon River, Iowa

    NASA Astrophysics Data System (ADS)

    Slater, Louise; Villarini, Gabriele; Bradley, Allen; Vecchi, Gabriel

    2016-04-01

    The state of Iowa (central United States) is regularly afflicted by severe natural hazards such as the 2008/2013 floods and the 2012 drought. To improve preparedness for these catastrophic events and allow Iowans to make more informed decisions about the most suitable water management strategies, we have developed a framework for medium to long range probabilistic seasonal streamflow forecasting for the Raccoon River at Van Meter, a 8900-km2 catchment located in central-western Iowa. Our flow forecasts use statistical models to predict seasonal discharge for low to high flows, with lead forecasting times ranging from one to ten months. Historical measurements of daily discharge are obtained from the U.S. Geological Survey (USGS) at the Van Meter stream gage, and used to compute quantile time series from minimum to maximum seasonal flow. The model is forced with basin-averaged total seasonal precipitation records from the PRISM Climate Group and annual row crop production acreage from the U.S. Department of Agriculture's National Agricultural Statistics Services database. For the forecasts, we use corn and soybean production from the previous year (persistence forecast) as a proxy for the impacts of agricultural practices on streamflow. The monthly precipitation forecasts are provided by eight Global Climate Models (GCMs) from the North American Multi-Model Ensemble (NMME), with lead times ranging from 0.5 to 11.5 months, and a resolution of 1 decimal degree. Additionally, precipitation from the month preceding each season is used to characterize antecedent soil moisture conditions. The accuracy of our modelled (1927-2015) and forecasted (2001-2015) discharge values is assessed by comparison with the observed USGS data. We explore the sensitivity of forecast skill over the full range of lead times, flow quantiles, forecast seasons, and with each GCM. Forecast skill is also examined using different formulations of the statistical models, as well as NMME forecast

  14. Causes of change in 20th century global river discharge

    NASA Astrophysics Data System (ADS)

    Gerten, Dieter; Rost, Stefanie; von Bloh, Werner; Lucht, Wolfgang

    2008-10-01

    A global vegetation and hydrology model (LPJmL) was applied to quantify the contributions of changing precipitation, temperature, atmospheric CO2 content, land use and irrigation to worldwide trends in 20th century river discharge (Q). Consistently with observations, Q decreased in parts of Africa, central/southern Asia and south-eastern Europe, and increased especially in parts of North America and western Asia. Based on the CRU TS2.1 climatology, total global Q rose over 1901-2002 (trend, 30.8 km3 a-2, equaling 7.7%), due primarily to increasing precipitation (individual effect, +24.7 km3 a-2). Global warming (-3.1), rising CO2 (+4.4), land cover changes (+5.9) and irrigation (-1.1) also had discernible effects. However, sign and magnitude of trends exhibited pronounced decadal variability and differed among precipitation forcing datasets. Since recent trends in these and other drivers of Q are mainly anthropogenic, we conclude that humans exert an increasing influence on the global water cycle.

  15. Increasing summer river discharge in southern California, USA, linked to urbanization

    NASA Astrophysics Data System (ADS)

    Townsend-Small, Amy; Pataki, Diane E.; Liu, Hongxing; Li, Zhaofu; Wu, Qiusheng; Thomas, Benjamin

    2013-09-01

    southern California relies heavily on imported water for domestic use. A synthesis of river discharge data in this region reveals that summer (June, July, and August) river discharge in watersheds that have at least 50% urban, suburban, and/or commercial land cover has increased by 250% or more over the past half-century, without any substantial precipitation during these months. Total annual discharge in the Los Angeles River has also increased at levels up to several hundred percent. Three factors likely contribute to our observations: (1) increased groundwater recharge rates from leaking water pipelines, (2) inputs of treated wastewater into streams and rivers, and (3) increased runoff or recharge due to over-irrigation of ornamental landscaping. In the southwestern United States, water importation consumes large amounts of energy and contributes to decline of river flows in source regions. Here we show that water importation also increases river flows in urban areas.

  16. Effect of groundwater discharge and river topography on nutrient component of rivers in Southern Korea and Western Japan

    NASA Astrophysics Data System (ADS)

    Onodera, S.; Shimizu, Y.; Kato, Y.; Saito, M.; Jige, M.; Hwang, J.

    2010-12-01

    Nutrient condition in water environment controls the ecosystem. Groundwater discharge to the oceans is significant as nutrient supply (Slomp et al, 2004 etc). This situation is similar to the nutrient condition in rivers. Most of river line generally is discharge area of groundwater, but a part of river line is recharge area of groundwater. In addition, nutrient concentration changes by the trap in dammed lake in the way of flowing to downstream. On the other hand, recent human activity has caused the intensive and excessive supply of nutrient. To clarify the nutrient condition in river environment, it is necessary to confirm the groundwater discharge to river as well as estimate the nutrient load by human activity. However, these types of researches have not been conducted enough. In this research, we aimed to confirm effects of groundwater on nutrient supply to rivers of various properties. Our research areas are around Hiroshima of western Japan and around Busan of southern Korea. We collected river water samples from upstream to downstream. All water samples were analyzed in the laboratory for the 222Rn, nutrient and inorganic element concentration, respectively. In addition, water samples of groundwater around there, bottom sea water, and river water at some points around the station were collected. Spatial variations from upstream to downstream in 222Rn and nutrient concentrations indicated decreasing trends. These suggest that head water is source area of nutrient. But some areas in midstream had high values, and it indicated heterogeneous groundwater supply. Phosphorus concentration increased in downstream. It was higher at groundwater of discharge area and downstream. This also suggests phosphorus supply by groundwater to rivers. Especially, the phosphorus concentration was high in the tidal river. This would be supplied by the diffusion from river bed sediment as well as by groundwater discharge.

  17. Modeling Peak Discharge within the Marengo River Watershed: Lessons for Restoration in the Saint Louis River Watershed

    EPA Science Inventory

    To more fully understand the hydrologic condition of the Marengo River Watershed, and to map specific locations most likely to have increased discharge and flow velocity (leading to more erosion and higher sediment loads) we modeled peak discharge for 35 different sub-watersheds ...

  18. Modeling Peak Discharge within the Marengo River Watershed: Lessons for Restoration in the Saint Louis River Watershed

    EPA Science Inventory

    To more fully understand the hydrologic condition of the Marengo River Watershed, and to map specific locations most likely to have increased discharge and flow velocity (leading to more erosion and higher sediment loads) we modeled peak discharge for 35 different sub-watersheds ...

  19. Sensitivity of global river discharges under Holocene and future climate conditions

    NASA Astrophysics Data System (ADS)

    Aerts, J. C. J. H.; Renssen, H.; Ward, P. J.; de Moel, H.; Odada, E.; Bouwer, L. M.; Goosse, H.

    2006-10-01

    A comparative analysis of global river basins shows that some river discharges are more sensitive to future climate change for the coming century than to natural climate variability over the last 9000 years. In these basins (Ganges, Mekong, Volta, Congo, Amazon, Murray-Darling, Rhine, Oder, Yukon) future discharges increase by 6-61%. These changes are of similar magnitude to changes over the last 9000 years. Some rivers (Nile, Syr Darya) experienced strong reductions in discharge over the last 9000 years (17-56%), but show much smaller responses to future warming. The simulation results for the last 9000 years are validated with independent proxy data.

  20. Verification of 1921 peak discharge at Skagit River near Concrete, Washington, using 2003 peak-discharge data

    USGS Publications Warehouse

    Mastin, M.C.; Kresch, D.L.

    2005-01-01

    The 1921 peak discharge at Skagit River near Concrete, Washington (U.S. Geological Survey streamflow-gaging station 12194000), was verified using peak-discharge data from the flood of October 21, 2003, the largest flood since 1921. This peak discharge is critical to determining other high discharges at the gaging station and to reliably estimating the 100-year flood, the primary design flood being used in a current flood study of the Skagit River basin. The four largest annual peak discharges of record (1897, 1909, 1917, and 1921) were used to determine the 100-year flood discharge at Skagit River near Concrete. The peak discharge on December 13, 1921, was determined by James E. Stewart of the U.S. Geological Survey using a slope-area measurement and a contracted-opening measurement. An extended stage-discharge rating curve based on the 1921 peak discharge was used to determine the peak discharges of the three other large floods. Any inaccuracy in the 1921 peak discharge also would affect the accuracies of the three other largest peak discharges. The peak discharge of the 1921 flood was recalculated using the cross sections and high-water marks surveyed after the 1921 flood in conjunction with a new estimate of the channel roughness coefficient (n value) based on an n-verification analysis of the peak discharge of the October 21, 2003, flood. The n value used by Stewart for his slope-area measurement of the 1921 flood was 0.033, and the corresponding calculated peak discharge was 240,000 cubic feet per second (ft3/s). Determination of a single definitive water-surface profile for use in the n-verification analysis was precluded because of considerable variation in elevations of surveyed high-water marks from the flood on October 21, 2003. Therefore, n values were determined for two separate water-surface profiles thought to bracket a plausible range of water-surface slopes defined by high-water marks. The n value determined using the flattest plausible slope was 0

  1. Effective discharge for sediment transport: the sorting role of river flow regimes

    NASA Astrophysics Data System (ADS)

    Basso, Stefano; Sprocati, Riccardo; Frascati, Alessandro; Marani, Marco; Schirmer, Mario; Botter, Gianluca

    2016-04-01

    The effective discharge is a key concept in geomorphology, river engineering and restoration. It is used to design the most stable channel configuration, to estimate sedimentation rate and lifespan of reservoirs and to characterize the hydrologic forcing in models studying long-term evolution of rivers. Previous empirical, theoretical and numerical studies found the effective discharge to be affected by climate, landscape and river morphology, type of transport (dissolved, suspended or bedload), and by streamflow variability. However, the heterogeneity of values observed for the effective discharge challenges a clear understanding of its pivotal drivers, and a consistent framework which explains observations carried out in different catchments and geographic areas is still lacking. This work relates the observed diversity of effective discharge values to the underlying heterogeneity of river flow regimes. The effective ratio (i.e. the ratio between effective discharge and mean streamflow) is derived as a function of the empirical exponent of the sediment rating curve and the streamflow variability, resulting from climatic and landscape drivers. The proposed analytic expression helps to disentangle hydrologic and landscape controls on the effective discharge, and highlights distinct effective ratios of persistent and erratic hydrologic regimes (respectively characterized by low and high flow variability), attributable to intrinsically different streamflow dynamics. The framework captures observed values of effective discharge for suspended sediment transport in a set of catchments of the continental United States, and may allow for first-order estimates of effective discharge in rivers belonging to different climatic regions.

  2. Geologic application of thermal-inertia mapping from satellite. [Powder River Basin in Wyoming and Montana

    NASA Technical Reports Server (NTRS)

    Offield, T. W. (Principal Investigator); Miller, S. H.; Watson, K.

    1978-01-01

    The author has identified the following significant results. The proportional and linear relationship between absolute and relative thermal inertia was theoretically evaluated, and a more accurate expression for thermal inertia was proposed. Radiometric and meteorological data from three stations in the Powder River Basin were acquired, as well as 400 miles of low altitude scanner data between July 25-28.

  3. Structural control on paleovalley development, muddy sandstone, Powder River basin, Wyoming

    SciTech Connect

    Gustason, E.R.; Wheeler, D.A.; Ryer, T.A.

    1988-07-01

    A subaerial unconformity within the Lower Cretaceous Muddy Sandstone in the Powder River basin developed during a late Albian sea level lowstand and resulted in a markedly rectangular drainage pattern. Numerous right-angle bends and perpendicular confluences of Muddy paleovalleys are believed to reflect syndepositional movement on basement faults and dissolution of salts in the Goose Egg Formation. A detailed subsurface analysis of geophysical logs from closely spaced wells reveals that up to 30 ft of vertical displacement occurred along northwest- and northeast-trending faults prior to and during the development of the subaerial unconformity. An analysis of a high-resolution magnetic survey (NewMag) of the Powder River basin reveals that numerous paleovalleys parallel the boundaries, or basement shear zones, between basement blocks. Small, irregularly shaped, thin intervals of the Permian Goose Egg Formation, which resemble karst topography, also occur along these northwest- and northeast-trending basement faults beneath Muddy paleovalleys. An arcuate Muddy paleovalley located in the northern Powder River basin parallels contours of isopach and trend surface maps of the Goose Egg Formation. These relationships suggest that the location and orientation of Muddy paleovalleys were controlled by a combination of movement along northwest- and northeast-trending faults and syntectonic dissolution of salt within the Goose Egg Formation. Simultaneous dissolution of Goose Egg salts and headward erosion of Muddy paleovalleys along this conjugate fault pattern also indicate that the Powder River basin was influenced by wrench fault tectonics during the late Albian.

  4. Geospatial data for coal beds in the Powder River Basin, Wyoming and Montana

    USGS Publications Warehouse

    Kinney, Scott A.; Scott, David C.; Osmonson, Lee M.; Luppens, James A.

    2015-01-01

    The purpose of this report is to provide geospatial data for various layers and themes in a Geographic Information System (GIS) format for the Powder River Basin, Wyoming and Montana. In 2015, as part of the U.S. Coal Resources and Reserves Assessment Project, the U.S. Geological Survey (USGS) completed an assessment of coal resources and reserves within the Powder River Basin, Wyoming and Montana. This report is supplemental to USGS Professional Paper 1809 and contains GIS data that can be used to view digital layers or themes, including the Tertiary limit of the Powder River Basin boundary, locations of drill holes, clinker, mined coal, land use and technical restrictions, geology, mineral estate ownership, coal thickness, depth to the top of the coal bed (overburden), and coal reliability categories. Larger scale maps may be viewed using the GIS data provided in this report supplemental to the page-size maps provided in USGS Professional Paper 1809. Additionally, these GIS data can be exported to other digital applications as needed by the user. The database used for this report contains a total of 29,928 drill holes, of which 21,393 are in the public domain. The public domain database is linked to the geodatabase in this report so that the user can access the drill-hole data through GIS applications. Results of this report are available at the USGS Energy Resources Program Web site,http://energy.usgs.gov/RegionalStudies/PowderRiverBasin.aspx.

  5. Assessment of coal geology, resources, and reserve base in the Powder River Basin, Wyoming and Montana

    USGS Publications Warehouse

    Scott, David C.; Luppens, James A.

    2013-01-01

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated in-place resources of 1.07 trillion short tons of coal in the Powder River Basin, Wyoming and Montana. Of that total, with a maximum stripping ratio of 10:1, recoverable coal was 162 billion tons. The estimate of economically recoverable resources was 25 billion tons.

  6. Charge–discharge properties of a layered-type Li(Ni,Co,Ti)O2 powder library

    PubMed Central

    Fujimoto, Kenjiro; Ikezawa, Keita; Ito, Shigeru

    2011-01-01

    A powder library of layered Li(Ni,Co,Ti)O2 (Ni ≤ 0.8, Ti ≤ 0.2) compounds was prepared by electrostatic spray deposition. From powder x-ray diffraction patterns, most of the powder library sintered at 700 ○C was indexed as a single phase belonging to the space group Rm. These results were almost identical to those obtained from a study by combinatorial exploration. We investigated the charge–discharge characteristics of the Li(Ni,Co,Ti)O2 powder library in a voltage range from 4.2 to 2.8 V at 1 C and found favorable cycling properties in the LiNixCo0.9-xTi0.1O2 (0 ≤x ≤ 0.6) compounds. PMID:27877430

  7. Charge-discharge properties of a layered-type Li(Ni,Co,Ti)O2 powder library.

    PubMed

    Fujimoto, Kenjiro; Ikezawa, Keita; Ito, Shigeru

    2011-10-01

    A powder library of layered Li(Ni,Co,Ti)O2 (Ni ≤ 0.8, Ti ≤ 0.2) compounds was prepared by electrostatic spray deposition. From powder x-ray diffraction patterns, most of the powder library sintered at 700 (○)C was indexed as a single phase belonging to the space group R[Formula: see text]m. These results were almost identical to those obtained from a study by combinatorial exploration. We investigated the charge-discharge characteristics of the Li(Ni,Co,Ti)O2 powder library in a voltage range from 4.2 to 2.8 V at 1 C and found favorable cycling properties in the LiNi x Co0.9-x Ti0.1O2 (0 ≤x ≤ 0.6) compounds.

  8. The association of the population recruitment of gulf menhaden, Brevoortia patronus, with Mississippi River discharge

    NASA Astrophysics Data System (ADS)

    Govoni, John J.

    1997-08-01

    Gulf menhaden, Brevoortia patronus, which constitutes a major industrial reduction fishery in the USA, spawn across the northern Gulf of Mexico with a focus of spawning about the Mississippi Delta. This species is estuarine dependent; adults spawn over the continental shelf and their larvae are transported, by mechanisms that are presently not well understood, to estuarine nursery areas. Larval gulf menhaden, along with some other surface oriented larval fishes, appear to aggregate along the Mississippi River plume front, while evidence of the ecological consequences of this aggregation in terms of the feeding, growth, and survival of larvae is ambiguous. On an annual scale, Mississippi River discharge is negatively associated with numbers of half year old recruits. Discharge of the Mississippi River and the population recruitment of gulf menhaden may be plausibly linked through the action of the river's plume and its front on the shoreward transport of larvae. Greater river discharge results in an expansive plume that might project larvae farther offshore and prolong the shoreward transport of larvae. An indirect, decadal scale, positive response of recruitment and river discharge is possible, but not certain. Recruitment became elevated after 1975 when river discharge increased and became highly variable. This response might owe to enhanced primary and secondary production driven by nutrient influx from the Mississippi River.

  9. The Critical Role of the Routing Scheme in Simulating Peak River Discharge in Global Hydrological Models

    NASA Technical Reports Server (NTRS)

    Zhao, Fang; Veldkamp, Ted I. E.; Frieler, Katja; Schewe, Jacob; Ostberg, Sebastian; Willner, Sven; Schauberger, Bernhard; Gosling, Simon N.; Schmied, Hannes Muller; Portmann, Felix T.; hide

    2017-01-01

    Global hydrological models (GHMs) have been applied to assess global flood hazards, but their capacity to capture the timing and amplitude of peak river discharge which is crucial in flood simulations has traditionally not been the focus of examination. Here we evaluate to what degree the choice of river routing scheme affects simulations of peak discharge and may help to provide better agreement with observations. To this end we use runoff and discharge simulations of nine GHMs forced by observational climate data (1971-2010) within the ISIMIP2a (Inter-Sectoral Impact Model Intercomparison Project phase 2a) project. The runoff simulations were used as input for the global river routing model CaMa-Flood (Catchment-based Macro-scale Floodplain). The simulated daily discharge was compared to the discharge generated by each GHM using its native river routing scheme. For each GHM both versions of simulated discharge were compared to monthly and daily discharge observations from 1701 GRDC (Global Runoff Data Centre) stations as a benchmark. CaMa-Flood routing shows a general reduction of peak river discharge and a delay of about two to three weeks in its occurrence, likely induced by the buffering capacity of floodplain reservoirs. For a majority of river basins, discharge produced by CaMa-Flood resulted in a better agreement with observations. In particular, maximum daily discharge was adjusted, with a multi-model averaged reduction in bias over about two-thirds of the analysed basin area. The increase in agreement was obtained in both managed and near-natural basins. Overall, this study demonstrates the importance of routing scheme choice in peak discharge simulation, where CaMa-Flood routing accounts for floodplain storage and backwater effects that are not represented in most GHMs. Our study provides important hints that an explicit parameterisation of these processes may be essential in future impact studies.

  10. An intercomparison of remote sensing river discharge estimation algorithms from measurements of river height, width, and slope

    NASA Astrophysics Data System (ADS)

    Durand, M.; Gleason, C. J.; Garambois, P. A.; Bjerklie, D.; Smith, L. C.; Roux, H.; Rodriguez, E.; Bates, P. D.; Pavelsky, T. M.; Monnier, J.; Chen, X.; Di Baldassarre, G.; Fiset, J.-M.; Flipo, N.; Frasson, R. P. d. M.; Fulton, J.; Goutal, N.; Hossain, F.; Humphries, E.; Minear, J. T.; Mukolwe, M. M.; Neal, J. C.; Ricci, S.; Sanders, B. F.; Schumann, G.; Schubert, J. E.; Vilmin, L.

    2016-06-01

    The Surface Water and Ocean Topography (SWOT) satellite mission planned for launch in 2020 will map river elevations and inundated area globally for rivers >100 m wide. In advance of this launch, we here evaluated the possibility of estimating discharge in ungauged rivers using synthetic, daily "remote sensing" measurements derived from hydraulic models corrupted with minimal observational errors. Five discharge algorithms were evaluated, as well as the median of the five, for 19 rivers spanning a range of hydraulic and geomorphic conditions. Reliance upon a priori information, and thus applicability to truly ungauged reaches, varied among algorithms: one algorithm employed only global limits on velocity and depth, while the other algorithms relied on globally available prior estimates of discharge. We found at least one algorithm able to estimate instantaneous discharge to within 35% relative root-mean-squared error (RRMSE) on 14/16 nonbraided rivers despite out-of-bank flows, multichannel planforms, and backwater effects. Moreover, we found RRMSE was often dominated by bias; the median standard deviation of relative residuals across the 16 nonbraided rivers was only 12.5%. SWOT discharge algorithm progress is therefore encouraging, yet future efforts should consider incorporating ancillary data or multialgorithm synergy to improve results.

  11. Annual variation in recruitment of freshwater mussels and its relationship with river discharge

    USGS Publications Warehouse

    Ries, Patricia R.; Newton, Teresa; Haro, Roger J.; Zigler, Steven J.; Davis, Mike

    2016-01-01

    Understanding variation in recruitment dynamics of native mussels and its relationship to river discharge will be useful in designing effective management strategies to enhance conservation of this imperilled fauna.

  12. Circulation in a bay influenced by flooding of a river discharging outside the bay

    NASA Astrophysics Data System (ADS)

    Kakehi, Shigeho; Takagi, Takamasa; Okabe, Katsuaki; Takayanagi, Kazufumi

    2017-03-01

    To investigate the influence of a river discharging outside a bay on circulation in the bay, we carried out current and salinity measurements from mooring systems and hydrographic observations in Matsushima Bay, Japan, and off the Naruse River, which discharges outside the bay. Previously, enhancement of horizontal circulation in the bay induced by increased freshwater input from the Naruse River was reported to have degraded the seedling yield of wild Pacific oysters in the bay, but the freshwater inflow from the river was not directly measured. Our hydrographic observations in Katsugigaura Strait, approximately 3 km southwest of the Naruse River mouth, detected freshwater derived from the river. The mooring data revealed that freshwater discharged by the river flowed into Matsushima Bay via the strait and that the freshwater transport increased when the river was in flood. The inflow through straits other than Katsugigaura was estimated by a box model analysis to be 26-145 m3 s-1 under normal river discharge conditions, and it decreased to 6 m3 s-1 during flood conditions. During flood events, the salt and water budgets in the bay were maintained by the horizontal circulation: inflow occurred mainly via Katsugigaura Strait, and outflow was mainly via other straits.

  13. Geochemistry of inorganic nitrogen in waters released from coal-bed natural gas production wells in the Powder River Basin, Wyoming.

    PubMed

    Smith, Richard L; Repert, Deborah A; Hart, Charles P

    2009-04-01

    Water originating from coal-bed natural gas (CBNG) production wells typically contains ammonium and is often disposed via discharge to ephemeral channels. A study conducted in the Powder River Basin, Wyoming, documented downstream changes in CBNG water composition, emphasizing nitrogen-cycling processes and the fate of ammonium. Dissolved ammonium concentrations from 19 CBNG discharge points ranged from 95 to 527 microM. Within specific channels, ammonium concentrations decreased with transport distance, with subsequent increases in nitrite and nitrate concentrations. Removal efficiency, or uptake, oftotal dissolved inorganic nitrogen (DIN) varied between channel types. DIN uptake was greater in the gentle-sloped, vegetated channel as compared to the incised, steep, and sparsely vegetated channel and was highly correlated with diel patterns of incident light and dissolved oxygen concentration. In a larger main channel with multiple discharge inputs (n=13), DIN concentrations were >300 microM, with pH > 8.5, after 5 km of transport. Ammonium represented 25-30% of the large-channel DIN, and ammonium concentrations remained relatively constant with time, with only a weak diel pattern evident. In July 2003, the average daily large-channel DIN load was 23 kg N day(-1) entering the Powder River, an amount which substantially increased the total Powder River DIN load after the channel confluence. These results suggest that CBNG discharge may be an important source of DIN to western watersheds, at least at certain times of the year, and that net oxidation and/or removal is dependent upon the extent of contact with sediment and biomass, type of drainage channel, and time of day.

  14. Geochemistry of inorganic nitrogen in waters released from coal-bed natural gas production wells in the Powder River Basin, Wyoming

    USGS Publications Warehouse

    Smith, Richard L.; Repert, Deborah A.; Hart, Charles P.

    2009-01-01

    Water originating from coal-bed natural gas (CBNG) production wells typically contains ammonium and is often disposed via discharge to ephemeral channels. A study conducted in the Powder River Basin, Wyoming, documented downstream changes in CBNG water composition, emphasizing nitrogen-cycling processes and the fate of ammonium. Dissolved ammonium concentrations from 19 CBNG discharge points ranged from 95 to 527 μM. Within specific channels, ammonium concentrations decreased with transport distance, with subsequent increases in nitrite and nitrate concentrations. Removal efficiency, or uptake, of total dissolved inorganic nitrogen (DIN) varied between channel types. DIN uptake was greater in the gentle-sloped, vegetated channel as compared to the incised, steep, and sparsely vegetated channel and was highly correlated with diel patterns of incident light and dissolved oxygen concentration. In a larger main channel with multiple discharge inputs (n = 13), DIN concentrations were >300 μM, with pH > 8.5, after 5 km of transport. Ammonium represented 25−30% of the large-channel DIN, and ammonium concentrations remained relatively constant with time, with only a weak diel pattern evident. In July 2003, the average daily large-channel DIN load was 23 kg N day−1entering the Powder River, an amount which substantially increased the total Powder River DIN load after the channel confluence. These results suggest that CBNG discharge may be an important source of DIN to western watersheds, at least at certain times of the year, and that net oxidation and/or removal is dependent upon the extent of contact with sediment and biomass, type of drainage channel, and time of day.

  15. Geochemistry of inorganic nitrogen in waters released from coal-bed natural gas production wells in the powder river basin, wyoming

    USGS Publications Warehouse

    Smith, R.L.; Repert, D.A.; Hart, C.P.

    2009-01-01

    Water originating from coal-bed natural gas (CBNG) production wells typically contains ammonium and is often disposed via discharge to ephemeral channels. A. study conducted in the Powder River Basin, Wyoming, documented downstream changes in CBNG water composition, emphasizing nitrogen-cycling processes and the fate of ammonium. Dissolved ammonium concentrations from 19 CBNG discharge points ranged from 95 to 527 ??M. Within specific channels, ammonium concentrations decreased with transport distance, with subsequent increases in nitrite and nitrate concentrations. Removal efficiency, or uptake, of total dissolved inorganic nitrogen (DIN) varied between channel types. DIN uptake was greater in the gentle-sloped, vegetated channel as compared to the incised, steep, and sparsely vegetated channel and was highly correlated with diel patterns of incident light and dissolved oxygen concentration. In a larger main channel with multiple discharge inputs (n = 13), DIN concentrations were >300 ??M, with pH > 8.5, after 5 km of transport. Ammonium represented 25-30% of the large-channel DIN, and ammonium concentrations remained relatively constant with time, with only a weak diel pattern evident. In July 2003, the average daily large-channel DIN load was 23 kg N day-1 entering the Powder River, an amount which substantially increased the total Powder River DIN load after the channel confluence. These results suggest that CBNG discharge may be an important source of DIN to western watersheds, at least at certain times of the year, and that net oxidation and/or removal is dependent upon the extent of contact with sediment and biomass, type of drainage channel, and time of day. ?? 2009 American Chemical Society.

  16. Geochemistry of Inorganic Nitrogen in Waters Released from Coal-Bed Natural Gas Production Wells in the Powder River Basin, Wyoming

    USGS Publications Warehouse

    Smith, Richard L.; Repert, Deborah A.; Hart, Charles P.

    2009-01-01

    Water originating from coal-bed natural gas (CBNG) production wells typically contains ammonium and is often disposed via discharge to ephemeral channels. A study conducted in the Powder River Basin, Wyoming, documented downstream changes in CBNG water composition, emphasizing nitrogen-cycling processes and the fate of ammonium. Dissolved ammonium concentrations from 19 CBNG discharge points ranged from 95 to 527 µM. Within specific channels, ammonium concentrations decreased with transport distance, with subsequent increases in nitrite and nitrate concentrations. Removal efficiency, or uptake, of total dissolved inorganic nitrogen (DIN) varied between channel types. DIN uptake was greater in the gentle-sloped, vegetated channel as compared to the incised, steep, and sparsely vegetated channel and was highly correlated with diel patterns of incident light and dissolved oxygen concentration. In a larger main channel with multiple discharge inputs (n = 13), DIN concentrations were >300 µM, with pH > 8.5, after 5 km of transport. Ammonium represented 25-30% of the large-channel DIN, and ammonium concentrations remained relatively constant with time, with only a weak diel pattern evident. In July 2003, the average daily large-channel DIN load was 23 kg N day-1 entering the Powder River, an amount which substantially increased the total Powder River DIN load after the channel confluence. These results suggest that CBNG discharge may be an important source of DIN to western watersheds, at least at certain times of the year, and that net oxidation and/or removal is dependent upon the extent of contact with sediment and biomass, type of drainage channel, and time of day.

  17. Remote Sensing and River Discharge Forecasting for Major Rivers in South Asia (Invited)

    NASA Astrophysics Data System (ADS)

    Webster, P. J.; Hopson, T. M.; Hirpa, F. A.; Brakenridge, G. R.; De-Groeve, T.; Shrestha, K.; Gebremichael, M.; Restrepo, P. J.

    2013-12-01

    The South Asia is a flashpoint for natural disasters particularly flooding of the Indus, Ganges, and Brahmaputra has profound societal impacts for the region and globally. The 2007 Brahmaputra floods affecting India and Bangladesh, the 2008 avulsion of the Kosi River in India, the 2010 flooding of the Indus River in Pakistan and the 2013 Uttarakhand exemplify disasters on scales almost inconceivable elsewhere. Their frequent occurrence of floods combined with large and rapidly growing populations, high levels of poverty and low resilience, exacerbate the impact of the hazards. Mitigation of these devastating hazards are compounded by limited flood forecast capability, lack of rain/gauge measuring stations and forecast use within and outside the country, and transboundary data sharing on natural hazards. Here, we demonstrate the utility of remotely-derived hydrologic and weather products in producing skillful flood forecasting information without reliance on vulnerable in situ data sources. Over the last decade a forecast system has been providing operational probabilistic forecasts of severe flooding of the Brahmaputra and Ganges Rivers in Bangldesh was developed (Hopson and Webster 2010). The system utilizes ECMWF weather forecast uncertainty information and ensemble weather forecasts, rain gauge and satellite-derived precipitation estimates, together with the limited near-real-time river stage observations from Bangladesh. This system has been expanded to Pakistan and has successfully forecast the 2010-2012 flooding (Shrestha and Webster 2013). To overcome the in situ hydrological data problem, recent efforts in parallel with the numerical modeling have utilized microwave satellite remote sensing of river widths to generate operational discharge advective-based forecasts for the Ganges and Brahmaputra. More than twenty remotely locations upstream of Bangldesh were used to produce stand-alone river flow nowcasts and forecasts at 1-15 days lead time. showing that

  18. Numerical simulations of river discharges, nutrient flux and nutrient dispersal in Jakarta Bay, Indonesia.

    PubMed

    van der Wulp, Simon A; Damar, Ario; Ladwig, Norbert; Hesse, Karl-J

    2016-09-30

    The present application of numerical modelling techniques provides an overview of river discharges, nutrient flux and nutrient dispersal in Jakarta Bay. A hydrological model simulated river discharges with a total of 90 to 377m(3)s(-1) entering Jakarta Bay. Daily total nitrogen and total phosphorus loads ranged from 40 to 174tons and 14 to 60tons, respectively. Flow model results indicate that nutrient gradients are subject to turbulent mixing by tides and advective transport through circulation driven by wind, barotropic and baroclinic pressure gradients. The bulk of nutrient loads originate from the Citarum and Cisadane rivers flowing through predominantly rural areas. Despite lower nutrient loads, river discharges from the urban area of Jakarta exhibit the highest impact of nutrient concentrations in the near shore area of Jakarta Bay and show that nutrient concentrations were not only regulated by nutrient loads but were strongly regulated by initial river concentrations and local flow characteristics.

  19. Assessing natural and anthropogenic influences on water discharge and sediment load in the Yangtze River, China.

    PubMed

    Zhao, Yifei; Zou, Xinqing; Liu, Qing; Yao, Yulong; Li, Yali; Wu, Xiaowei; Wang, Chenglong; Yu, Wenwen; Wang, Teng

    2017-12-31

    The water discharge and sediment load of rivers are changing substantially under the impacts of climate change and human activities, becoming a hot issue in hydro-environmental research. In this study, the water discharge and sediment load in the mainstream and seven tributaries of the Yangtze River were investigated by using long-term hydro-meteorological data from 1953 to 2013. The non-parametric Mann-Kendall test and double mass curve (DMC) were used to detect trends and abrupt change-points in water discharge and sediment load and to quantify the effects of climate change and human activities on water discharge and sediment load. The results are as follows: (1) the water discharge showed a non-significant decreasing trend at most stations except Hukou station. Among these, water discharge at Dongting Lake and the Min River basin shows a significant decreasing trend with average rates of -13.93×10(8)m(3)/year and -1.8×10(8)m(3)/year (P<0.05), respectively. However, the sediment load exhibited a significant decreasing trend in all tributaries of the Yangtze River. (2) No significant abrupt change-points were detected in the time series of water discharge for all hydrological stations. In contrast, significant abrupt change-points were detected in sediment load, most of these changes appeared in the late 1980s. (3) The water discharge was mainly influenced by precipitation in the Yangtze River basin, whereas sediment load was mainly affected by climate change and human activities; the relative contribution ratios of human activities were above 70% for the Yangtze River. (4) The decrease of sediment load has directly impacted the lower Yangtze River and the delta region. These results will provide a reference for better resource management in the Yangtze River Basin. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Instream biological assessment of NPDES point source discharges at the Savannah River Site, 1997-1998

    SciTech Connect

    Specht, W.L.

    2000-02-28

    The Savannah River Site currently has 33 permitted NPDES outfalls that have been permitted by the South Carolina Department of Health an Environmental Control to discharge to SRS streams and the Savannah River. In order to determine the cumulative impacts of these discharges to the receiving streams, a study plan was developed to perform in-stream assessments of the fish assemblages, macroinvertebrate assemblages, and habitats of the receiving streams.

  1. The critical role of the routing scheme in simulating peak river discharge in global hydrological models

    NASA Astrophysics Data System (ADS)

    Zhao, Fang; Veldkamp, Ted I. E.; Frieler, Katja; Schewe, Jacob; Ostberg, Sebastian; Willner, Sven; Schauberger, Bernhard; Gosling, Simon N.; Müller Schmied, Hannes; Portmann, Felix T.; Leng, Gobias; Huang, Maoyi; Liu, Xingcai; Tang, Qiuhong; Hanasaki, Naota; Biemans, Hester; Gerten, Dieter; Satoh, Yusuke; Pokhrel, Yadu; Stacke, Tobias; Ciais, Philippe; Chang, Jinfeng; Ducharne, Agnes; Guimberteau, Matthieu; Wada, Yoshihide; Kim, Hyungjun; Yamazaki, Dai

    2017-07-01

    Global hydrological models (GHMs) have been applied to assess global flood hazards, but their capacity to capture the timing and amplitude of peak river discharge—which is crucial in flood simulations—has traditionally not been the focus of examination. Here we evaluate to what degree the choice of river routing scheme affects simulations of peak discharge and may help to provide better agreement with observations. To this end we use runoff and discharge simulations of nine GHMs forced by observational climate data (1971-2010) within the ISIMIP2a project. The runoff simulations were used as input for the global river routing model CaMa-Flood. The simulated daily discharge was compared to the discharge generated by each GHM using its native river routing scheme. For each GHM both versions of simulated discharge were compared to monthly and daily discharge observations from 1701 GRDC stations as a benchmark. CaMa-Flood routing shows a general reduction of peak river discharge and a delay of about two to three weeks in its occurrence, likely induced by the buffering capacity of floodplain reservoirs. For a majority of river basins, discharge produced by CaMa-Flood resulted in a better agreement with observations. In particular, maximum daily discharge was adjusted, with a multi-model averaged reduction in bias over about 2/3 of the analysed basin area. The increase in agreement was obtained in both managed and near-natural basins. Overall, this study demonstrates the importance of routing scheme choice in peak discharge simulation, where CaMa-Flood routing accounts for floodplain storage and backwater effects that are not represented in most GHMs. Our study provides important hints that an explicit parameterisation of these processes may be essential in future impact studies.

  2. Choice of routing scheme considerably influences peak river discharge simulation in global hydrological models

    NASA Astrophysics Data System (ADS)

    Zhao, Fang; Veldkamp, Ted; Schauberger, Bernhard; Willner, Sven; Yamazaki, Dai

    2017-04-01

    Global hydrological models (GHMs) have been applied to assess global flood hazards. However, their capacity to capture the timing and amplitude of peak river discharge—which is crucial in flood simulations—has traditionally not been the focus of examination. Here we evaluate to what degree the choice of river routing scheme affects simulations of peak discharge and may help to provide better agreement with observations. To this end we use runoff and discharge simulations of nine GHMs forced by observational climate data (1971-2010) within the ISIMIP2a project. The runoff simulations were used as input for the global river routing model CaMa-Flood. The simulated daily discharges were compared to the discharge generated by each GHM using its native river routing scheme. For each GHM both versions of simulated discharge were compared to monthly and daily discharge observations from 1701 GRDC stations as a benchmark. CaMa-Flood routing shows a general reduction of peak river discharge and a delay of about two to three weeks in its occurrence, probably induced by the buffering capacity of floodplain reservoirs. For most river basins, discharge produced by CaMa-Flood resulted in a better agreement with observations. In particular, maximum daily discharge was adjusted, with a multi-model averaged reduction in bias over more than 60% of the basin area. The increase in agreement was obtained in both managed and near-natural basins. Overall, this study demonstrates the importance of routing scheme in peak discharge simulation, where CaMa-Flood routing accounts for floodplain storage and backwater effects that are not present in most GHMs. Our study provides important hints that an explicit parameterisation of these processes may be essential in future impact studies.

  3. Interactions of river discharge parameterizations with the Madden Julian oscillation in the CESM

    NASA Astrophysics Data System (ADS)

    DeMott, C. A.; Tseng, Y. H.; Bryan, F.

    2016-12-01

    River discharge in the tropical Warm Pool is a source of fresh water to the upper ocean, which can help stabilize the upper ocean, reduce ocean mixing, and promote radiation-driven surface warming. Large rivers, such as the Ganges, that drain large land masses provide quasi-steady freshening during certain seasons. Freshening from rivers that drain smaller land masses, such as islands within the Maritime Continent, is more regulated by rainfall. The Madden Julian oscillation (MJO) regulates instraseasonal rainfall, SST, and surface salinity across the Warm Pool, and is sensitive to the ocean response to this forcing. The effects of estuarine river discharge on upper ocean stratification and interactions with the MJO are explored using two different estuary parameterizations in the Community Earth System Model (CESM). In the control simulation (CTR), river discharge is spread uniformly onto the ocean surface over an artificially chosen length scale using the virtual salt flux approach. In the experimental configuration, river discharge is confined to the ocean model grid point containing the river delta, and mixed vertically with a two-layer estuary box model (EBM). In EBM, the temperature and salinity distribution is driven mainly by oceanic mixing and advection without ad-hoc horizontal spreading. Compared to EBM, over-dispersal of river runoff in CTR leads to fresher surface waters, shallower ocean mixed layers, and more variable SSTs throughout the Warm Pool. In CTR, river discharge is transported to a larger area by surface currents. Specifically, fresh water from the Ganges contributes to a low salinity, warm SST band near 10N in the central Indian Ocean; in the Indonesian Seas, overly dispersed runoff contributes to a shallower mixed layer and larger SST increases during the MJO suppressed phase. MJO convection and propagation characteristics suggest that the MJO in CTR benefits from the overly dispersed river discharge, while the MJO in EBM is less impacted.

  4. Estimation of Direct and Indirect Discharge of Shallow Groundwater Nutrients into Rivers

    NASA Astrophysics Data System (ADS)

    Ouyang, Y.

    2008-05-01

    Pollution of the Lower St. Johns River, Florida due to leaching, discharging, and loading of excess nutrients is a problem of increasing environmental and ecological concern. While surface runoff and atmospheric deposition of excess nutrients into the LSJR have received great attention, the mechanisms by which nutrients enter the LSJR through shallow groundwater discharge have not been well documented. Currently, mixed results are reported regarding the contamination of streams with shallow groundwater nutrients. Some studies show that about 70-80 percent of groundwater nutrients are removed through the wetland before entering the streams, while others observe that groundwater discharge associated with nutrient seepage into estuaries and rivers can be significant across a wide range of temporal and spatial scales. More interestingly, one study demonstrates that discharge of shallow groundwater nutrients into the streams goes both indirectly through wetlands and directly beneath wetlands. In this study, a dynamic model for shallow groundwater nutrient discharge into rivers is developed using STELLA. The structure of the model consisted of time-dependent simultaneous discharge of water and nutrients from shallow aquifers into rivers indirectly through wetland attenuations and directly beneath wetlands. Field data are used to test the model prior to its application in a septic area of the LSJR basin. Our study suggests that the model, developed with STELLA, is a useful tool for estimating shallow groundwater nutrient discharge into rivers.

  5. Surface Preparation of Powder Metallurgical Tool Steels by Means of Wire Electrical Discharge Machining

    NASA Astrophysics Data System (ADS)

    Hatami, Sepehr; Shahabi-Navid, Mehrdad; Nyborg, Lars

    2012-09-01

    The surface of two types of powder metallurgical (PM) tool steels ( i.e., with and without nitrogen) was prepared using wire electrical discharge machining (WEDM). From each grade of tool steel, seven surfaces corresponding to one to seven passes of WEDM were prepared. The WEDM process was carried out using a brass wire as electrode and deionized water as dielectric. After each WEDM pass the surface of the tool steels was thoroughly examined. Surface residual stresses were measured by the X-ray diffraction (XRD) technique. The measured stresses were found to be of tensile nature. The surface roughness of the WEDM specimens was measured using interference microscopy. The surface roughness as well as the residual stress measurements indicated an insignificant improvement of these parameters after four passes of WEDM. In addition, the formed recast layer was characterized by means of scanning electron microscopy (SEM), XRD, and X-ray photoelectron spectroscopy (XPS). The characterization investigation clearly shows diffusion of copper and zinc from the wire electrode into the work material, even after the final WEDM step. Finally, the importance of eliminating excessive WEDM steps is thoroughly discussed.

  6. Application of Satellite Based Laser Altimetry to Estimation of River Hydraulics and Remote Estimation of River Discharge

    NASA Astrophysics Data System (ADS)

    Bjerklie, D. M.; Birkett, C. M.; Li, Y.; Hofton, M. A.

    2009-12-01

    The potential for using satellite-based measurements of water-surface elevation to assist in measuring and monitoring the flow of rivers has been well documented. We develop specific methods that use satellite-based altimetry and remote measurements of river width to estimate instantaneous discharge, and demonstrate a practical application by combining these estimates with ground-based river-monitoring data and hydrologic modeling to fill in gaps in the ground-based river gaging network. Data from the ICEASat GLAS laser altimeter for the period 2003 to 2009 (GLA14 and GLA06 products, Release 28 and 29) were retrieved, calibrated, and validated to obtain measures of water-surface elevation and water-surface slope within several reaches of the Mississippi and Missouri river channels. These measurements were coupled with Landsat-derived estimates of the river channel width for the same reaches to estimate the depth, velocity, and discharge of the rivers. The data are analyzed and used to provide reasonably accurate estimates of instantaneous and daily river discharge. We also assess the range of accuracy of the discharge estimates. An alternative application that combines satellite-based water-surface elevation and slope measurements with ground-based measurements and precipitation runoff modeling is demonstrated in the context of the potential development of a spatially contiguous river gaging network. We discuss and assess the implications of issues concerning the observation frequency, accuracy of the altimetric estimates of water-surface elevation at points and the resultant estimate of water-surface slope with regard to the resolution and monitoring of river hydraulic conditions.

  7. IDENTIFYING DISCHARGE ZONES OF ARSENIC IN THE GOOSE RIVER BASIN, MAINE

    EPA Science Inventory

    Groundwater discharge areas are simulated from water balance modeling and kriging of oxygen isotopes in groundwater within the Goose River basin. Groundwater fluxes of discharge range from -10 cm yr-1 to < -25 cm yr-1 and are associated with areas of elevated arsenic in wells. De...

  8. IDENTIFYING DISCHARGE ZONES OF ARSENIC IN THE GOOSE RIVER BASIN, MAINE

    EPA Science Inventory

    Groundwater discharge areas are simulated from water balance modeling and kriging of oxygen isotopes in groundwater within the Goose River basin. Groundwater fluxes of discharge range from -10 cm yr-1 to < -25 cm yr-1 and are associated with areas of elevated arsenic in wells. De...

  9. The effect on river discharge estimation by considering an interaction between land surface process and river routing process

    NASA Astrophysics Data System (ADS)

    Yorozu, K.; Tachikawa, Y.

    2015-06-01

    There is much research assessing the impact of climate change on the hydrologic cycle. However, it has often focused on a specific hydrologic process, without considering the interaction among hydrologic processes. In this study, a distributed hydrologic model considering the interaction between flow routing and land surface processes was developed, and its effect on river discharge estimation was investigated. The model enables consideration of flow routing, irrigation withdrawal from rivers at paddy fields, crop growth depending on water and energy status, and evapotranspiration based on meteorological, soil water and vegetation status. To examine the effects of hydrologic process interaction on river discharge estimation, a developed model was applied to the Chao Phraya river basin using near surface meteorological data collected by the Japanese Meteorological Research Institute's Atmospheric General Circulation Model (MRI-AGCM3.2S) with TL959 spatial resolution as forcing data. Also, a flow routing model, which was part of the developed model, was applied independently, using surface and subsurface runoff data from the same GCM. In the results, the developed model tended to estimate a smaller river discharge than was estimated by the river routing model, because of the irrigation effect. In contrast, the annual maximum daily discharge calculated by the developed model was 24% greater than that by the flow routing model. It is assumed that surface runoff in the developed model was greater than that in the flow routing model because the soil water content was maintained at a high level through irrigation withdrawal. As for drought discharge, which is defined as the 355th largest daily discharge, the developed model gave a discharge 2.7-fold greater than the flow routing model. It seems that subsurface runoff in the developed model was greater than that in the flow routing model. The results of this study suggest that considering hydrologic interaction in a

  10. SEASONAL VARIATIONS IN RIVER DISCHARGE AND NUTRIENT EXPORT TO A NORTHEASTERN PACIFIC ESTUARY (FINAL)

    EPA Science Inventory

    Seasonal variations in dissolved nitrogen and silica loadings were related to seasonal variability in river discharge. Dissolved nutrient concentrations measured weekly at three stations in the Yaquina River, Oregon from 1999 through 2001, and then monthly in 2002 were used as th...

  11. SEASONAL VARIATIONS IN RIVER DISCHARGE AND NUTRIENT EXPORT TO A NORTHEASTERN PACIFIC ESTUARY

    EPA Science Inventory

    Seasonal variations in dissolved nitrogen and silica loadings were related to seasonal variability in river discharge. Dissolved nutrient concentrations measured weekly at three stations in the Yaquina River, Oregon from 1999 through 2001, and then monthly in 2002 were used as th...

  12. SEASONAL VARIATIONS IN RIVER DISCHARGE AND NUTRIENT EXPORT TO A NORTHEASTERN PACIFIC ESTUARY

    EPA Science Inventory

    Seasonal variations in dissolved nitrogen and silica loadings were related to seasonal variability in river discharge. Dissolved nutrient concentrations measured weekly at three stations in the Yaquina River, Oregon from 1999 through 2001, and then monthly in 2002 were used as th...

  13. Toward global mapping of river discharge using satellite images and at-many-stations hydraulic geometry.

    PubMed

    Gleason, Colin J; Smith, Laurence C

    2014-04-01

    Rivers provide critical water supply for many human societies and ecosystems, yet global knowledge of their flow rates is poor. We show that useful estimates of absolute river discharge (in cubic meters per second) may be derived solely from satellite images, with no ground-based or a priori information whatsoever. The approach works owing to discovery of a characteristic scaling law uniquely fundamental to natural rivers, here termed a river's at-many-stations hydraulic geometry. A first demonstration using Landsat Thematic Mapper images over three rivers in the United States, Canada, and China yields absolute discharges agreeing to within 20-30% of traditional in situ gauging station measurements and good tracking of flow changes over time. Within such accuracies, the door appears open for quantifying river resources globally with repeat imaging, both retroactively and henceforth into the future, with strong implications for water resource management, food security, ecosystem studies, flood forecasting, and geopolitics.

  14. Discharge and other hydraulic measurements for characterizing the hydraulics of Lower Congo River

    USGS Publications Warehouse

    Oberg, Kevin; Shelton, John M.; Gardiner, Ned; Jackson, P. Ryan

    2009-01-01

    The first direct measurements of discharge of the Lower Congo River below Malebo Pool and upstream from Kinganga, Democratic Republic of Congo (DRC) were made in July 2008 using acoustic Doppler current profilers, differential GPS, and echo sounders. These measurements were made in support of research that is attempting to understand the distribution of fish species in the Lower Congo River and reasons for separation of species within this large river. Analyses of these measurements show that the maximum depth in the Lower Congo River was in excess of 200 m and maximum water velocities were greater than 4 m/s. The discharge measured near Luozi, DRC was 35,800 m3/s, and decreased slightly beginning midway through the study. Local bedrock controls seem to have a large effect on the flow in the river, even in reaches without waterfalls and rapids. Dramatic changes in bed topography are evident in transects across the river.

  15. Modeling the influence of river discharge on salt intrusion and residual circulation in Danshuei River estuary, Taiwan

    USGS Publications Warehouse

    Liu, W.-C.; Chen, W.-B.; Cheng, R.T.; Hsu, M.-H.; Kuo, A.Y.

    2007-01-01

    A 3-D, time-dependent, baroclinic, hydrodynamic and salinity model was implemented and applied to the Danshuei River estuarine system and the adjacent coastal sea in Taiwan. The model forcing functions consist of tidal elevations along the open boundaries and freshwater inflows from the main stream and major tributaries in the Danshuei River estuarine system. The bottom friction coefficient was adjusted to achieve model calibration and verification in model simulations of barotropic and baroclinic flows. The turbulent diffusivities were ascertained through comparison of simulated salinity time series with observations. The model simulation results are in qualitative agreement with the available field data. The validated model was then used to investigate the influence of freshwater discharge on residual current and salinity intrusion under different freshwater inflow condition in the Danshuei River estuarine system. The model results reveal that the characteristic two-layered estuarine circulation prevails most of the time at Kuan-Du station near the river mouth. Comparing the estuarine circulation under low- and mean flow conditions, the circulation strengthens during low-flow period and its strength decreases at moderate river discharge. The river discharge is a dominating factor affecting the salinity intrusion in the estuarine system. A correlation between the distance of salt intrusion and freshwater discharge has been established allowing prediction of salt intrusion for different inflow conditions. ?? 2007 Elsevier Ltd. All rights reserved.

  16. Shovelnose sturgeon spawning in relation to varying discharge treatments in a Missouri River tributary

    USGS Publications Warehouse

    Goodman, B.J.; Guy, C.S.; Camp, S.L.; Gardner, W.M.; Kappenman, K.M.; Webb, M.A.H.

    2013-01-01

    Many lotic fish species use natural patterns of variation in discharge and temperature as spawning cues, and these natural patterns are often altered by river regulation. The effects of spring discharge and water temperature variation on the spawning of shovelnose sturgeon Scaphirhynchus platorynchus have not been well documented. From 2006 through 2009, we had the opportunity to study the effects of experimental discharge levels on shovelnose sturgeon spawning in the lower Marias River, a regulated tributary to the Missouri River in Montana. In 2006, shovelnose sturgeon spawned in the Marias River in conjunction with the ascending, peak (134 m3/s) and descending portions of the spring hydrograph and water temperatures from 16°C to 19°C. In 2008, shovelnose sturgeon spawned in conjunction with the peak (118 m3/s) and descending portions of the spring hydrograph and during a prolonged period of increased discharge (28–39 m3/s), coupled with water temperatures from 11°C to 23°C in the lower Marias River. No evidence of shovelnose sturgeon spawning was documented in the lower Marias River in 2007 or 2009 when discharge remained low (14 and 20 m3/s) despite water temperatures suitable and optimal (12°C-24°C) for shovelnose sturgeon embryo development. A similar relationship between shovelnose sturgeon spawning and discharge was observed in the Teton River. These data suggest that discharge must reach a threshold level (28 m3/s) and should be coupled with water temperatures suitable (12°C-24°C) or optimal (16°C-20°C) for shovelnose sturgeon embryo development to provide a spawning cue for shovelnose sturgeon in the lower Marias River.

  17. Simulating river discharge in a snowy region of Japan using output from a regional climate model

    NASA Astrophysics Data System (ADS)

    Ma, X.; Kawase, H.; Adachi, S.; Fujita, M.; Takahashi, H. G.; Hara, M.; Ishizaki, N.; Yoshikane, T.; Hatsushika, H.; Wakazuki, Y.; Kimura, F.

    2013-07-01

    Snowfall amounts have fallen sharply along the eastern coast of the Sea of Japan since the mid-1980s. Toyama Prefecture, located approximately in the center of the Japan Sea region, includes high mountains of the northern Japanese Alps on three of its sides. The scarcity of meteorological observation points in mountainous areas limits the accuracy of hydrological analysis. With the development of computing technology, a dynamical downscaling method is widely applied into hydrological analysis. In this study, we numerically modeled river discharge using runoff data derived by a regional climate model (4.5-km spatial resolution) as input data to river networks (30-arcseconds resolution) for the Toyama Prefecture. The five main rivers in Toyama (the Oyabe, Sho, Jinzu, Joganji, and Kurobe rivers) were selected in this study. The river basins range in area from 368 to 2720 km2. A numerical experiment using climate comparable to that at present was conducted for the 1980s and 1990s. The results showed that seasonal river discharge could be represented and that discharge was generally overestimated compared with measurements, except for Oyabe River discharge, which was always underestimated. The average correlation coefficient for 10-year average monthly mean discharge was 0.8, with correlation coefficients ranging from 0.56 to 0.88 for all five rivers, whereas the Nash-Sutcliffe efficiency coefficient indicated that the simulation accuracy was insufficient. From the water budget analysis, it was possible to speculate that the lack of accuracy of river discharge may be caused by insufficient accuracy of precipitation simulation.

  18. Powder River: data for cross-channel profiles at 22 sites in southeastern Montana from 1975 through 2012

    USGS Publications Warehouse

    Moody, John A.; Meade, Robert H.

    2013-01-01

    Powder River rises in the Bighorn Mountains of Wyoming and flows northward through a semi-arid landscape in Wyoming and Montana to the Yellowstone River. The river drains an area of 34,700 km2 and has an average discharge of about 500 million m3 y-1 or 16 m3 s-1. This view of the river looking northward, and hence downstream, was taken in October 2012 (see study reach map), about 20 km north of the Wyoming-Montana state line, about 4 km downstream from an operating gaging station at Moorhead, Montana (USGS station number 06324500), and about 80 river km upstream from a discontinued gaging station at Broadus, Montana (USGS station number 06324710). The river is emerging from a narrowly-confined reach, and the valley widens northward, bordered by hills of the coal-bearing Fort Union Formation. The river in this photo is at about bed-full flow (12 m3 s-1, Moody and others, 1999), and several riffles with disturbed water can be seen downstream between smooth glassy reaches of the river. A narrow band (~2-4 m wide) of reddish sedge (Scirpus spp.) grows just above the bed-full level along the edge of water with a wider band of mixed grasses (Agropyron repens, A. pauciflorum, Bromus inermis, Elymus canadenis, Spartina pectinata, and S. cynosoroids), willow (Salix exigua), tamarisk (Tamirix ramosissima) and small cottonwood seedlings and trees (Populus sargentii) on the flood plain. Three terrace levels have been identified along the river (Leopold and Miller, 1954; Moody and Meade, 2008). The first is the Lightning terrace with small cottonwood trees (seen here without leaves) adjacent to the floodplain in the right-center of the photo. The second is the Moorcroft terrace seen best forming the left bank and extending as a flat surface to the left (west) with a few large cottonwood trees still retaining their green leaves. The third is the colluvial Kaycee terrace that grades slowly upwards and meets the hills of the Fort Union Formation. It can be seen on the right side

  19. Simulation of stream discharge and transport of nitrate and selected herbicides in the Mississippi River Basin

    USGS Publications Warehouse

    Broshears, R.E.; Clark, G.M.; Jobson, H.E.

    2001-01-01

    Stream discharge and the transport of nitrate, atrazine, and metolachlor in the Mississippi River Basin were simulated using the DAFLOW/BLTM hydrologic model. The simulated domain for stream discharge included river reaches downstream from the following stations in the National Stream Quality Accounting Network: Mississippi River at Clinton, IA; Missouri River at Hermann, MO: Ohio River at Grand Chain, IL: And Arkansas River at Little Rock, AR. Coefficients of hydraulic geometry were calibrated using data from water year 1996; the model was validated by favourable simulation of observed discharges in water years 1992-1994. The transport of nitrate, atrazine, and metolachlor was simulated downstream from the Mississippi River at Thebes, IL, and the Ohio River at Grand Chain. Simulated concentrations compared favourably with observed concentrations at Baton Rouge, LA. Development of this model is a preliminary step in gaining a more quantitative understanding of the sources and fate of nutrients and pesticides delivered from the Mississippi River Basin to the Gulf of Mexico.

  20. Simulation of stream discharge and transport of nitrate and selected herbicides in the Mississippi River Basin

    NASA Astrophysics Data System (ADS)

    Broshears, Robert E.; Clark, Gregory M.; Jobson, Harvey E.

    2001-05-01

    Stream discharge and the transport of nitrate, atrazine, and metolachlor in the Mississippi River Basin were simulated using the DAFLOW/BLTM hydrologic model. The simulated domain for stream discharge included river reaches downstream from the following stations in the National Stream Quality Accounting Network: Mississippi River at Clinton, IA; Missouri River at Hermann, MO; Ohio River at Grand Chain, IL; and Arkansas River at Little Rock, AR. Coefficients of hydraulic geometry were calibrated using data from water year 1996; the model was validated by favourable simulation of observed discharges in water years 1992-1994. The transport of nitrate, atrazine, and metolachlor was simulated downstream from the Mississippi River at Thebes, IL, and the Ohio River at Grand Chain. Simulated concentrations compared favourably with observed concentrations at Baton Rouge, LA. Development of this model is a preliminary step in gaining a more quantitative understanding of the sources and fate of nutrients and pesticides delivered from the Mississippi River Basin to the Gulf of Mexico. Published in 2001 by John Wiley & Sons, Ltd.

  1. How accurately will SWOT measurements be able to characterize river discharge?

    NASA Astrophysics Data System (ADS)

    Durand, M.; Alsdorf, D.; Bates, P.; Rodríguez, E.; Andreadis, K.; Clark, E.

    2008-12-01

    The Surface Water and Ocean Topography (SWOT) mission is a swath mapping radar altimeter that would provide new measurements of inland water surface elevation (WSE) for rivers, lakes, wetlands and reservoirs. SWOT has been recommended by the National Research Council Decadal Survey to measure ocean topography as well as WSE over land; the proposed launch date timeframe is between 2013 - 2016. SWOT WSE estimates would provide a source of information for characterizing streamflow globally. In this paper, we evaluate the accuracy of river discharge estimates obtained from SWOT measurements over the Ohio River and eight of its major tributaries within the context of a virtual mission (VM). SWOT VM measurements are obtained by simulation from the hydrodynamic model LISFLOOD, using USGS streamflow gages as boundary conditions and validation data. SWOT measurements are then input into an algorithm to obtain estimates of discharge variations. The algorithm is based on Manning's equation, in which river width and slope are obtained from SWOT, roughness is estimated a priori. Three different algorithms are used to estimate depth. SWOT discharge estimates are compared to the discharge simulated by LISFLOOD. In this way, we are able to characterize the accuracy of SWOT estimates of instantaneous discharge. More specifically, we characterize how SWOT accuracy varies as a function of the river characteristics and contributing area, such as Strahler order. More accurate depth and discharge estimates can be obtained by data assimilation, but will be more computationally expensive.

  2. Parameterization of SURFEX-TOPMODEL river velocity based on instant discharge dependency

    NASA Astrophysics Data System (ADS)

    Nedkov, Nikolay; Artinyan, Eram; Tsarev, Petko

    2016-04-01

    SURFEX-TOPMODEL distributed physical model is used to analyze and forecast stream flow discharges including flash floods occurring in a Mediterranean river basin in Bulgaria. River velocity is one of the parameters that need to be calibrated in order to achieve acceptable representation of peak floods but in the same time to produce a smooth hydrograph during the low flow periods. The coupled model showed great sensibility to the parameter but when focusing to reproduce high peaks low discharge hydrograph presented unrealistic small peaks too. The dependency between the measured instant discharge and mean section velocity was established for the Bulgarian hydrometric stations on rivers using 20 years of direct discharge-velocity measures of the National Institute of Meteorology and Hydrology of Bulgaria. The relationship is used to avoid the calibration of the velocity parameter for the measured cross-sections. It was coded within the model thus permitting dynamical adjustment of the velocity with respect to the computed instant discharge in the river section. We present the results of river flow simulations with the modified parameterization compared to those with the original model for the hydrological year 2014-2015. Keywords: SURFEX-TOP, river speed parameter

  3. Effects of River Discharge on Hyporheic Exchange Flows in Large Gravel-Bed Rivers: An Empirical Study

    NASA Astrophysics Data System (ADS)

    Hanrahan, T. P.

    2004-12-01

    Current in situ understanding of exchange flows in riverbeds, and the ecological implications, has been largely derived from research in small streams. Comparatively little research has been conducted in large rivers, making it difficult to "scale-up" (spatially and temporally) our knowledge from small streams to understand observations and develop predictive models for large rivers. The studies conducted on small streams typically encompass too few sites, over too small of a longitudinal scale, with discrete sampling events (versus continuous sampling), resulting in an understanding of processes that is not directly transferrable to the study of much larger rivers. In addition, very few of these studies evaluate the effects of variable river discharge on riverbed exchange flows. We studied exchange flows between the river and riverbed at 14 sites distributed throughout 160km of the Snake River in Hells Canyon, Idaho, USA. Interactions between river water and pore water within the riverbed were quantified through the use of self-contained temperature and water level data loggers suspended inside of piezometers. The data were recorded at 20 min intervals over a period of 200 days when the mean daily discharge was 218-605 m3 s-1, with hourly stage changes as large as 1.5 m. The effects of discharge on vertical exchange between the river and riverbed were evaluated through measured hydraulic and temperature gradients, and the application of a numerical model. The vertical hydraulic gradients (VHG) between the river and the riverbed suggested the potential for predominantly small magnitude vertical exchange. The VHG also showed little relationship to changes in river discharge at most sites. Despite the relatively small VHG at most sites, the results from the numerical modeling suggested that there was significant vertical hydrologic exchange during all time periods. Our observations confirm the presence, and quantify the relative importance, of both advective and

  4. Hydroacoustic Current Meters for the Measurement of Discharge in Shallow Rivers and Streams

    USGS Publications Warehouse

    Morlock, S.E.; Fisher, G.T.; ,

    2002-01-01

    The U.S. Geological Survey (USGS) is evaluating the use of hydroacoustic current meters for making discharge measurements in shallow rivers and streams. The USGS historically has made discharge measurements in shallow rivers using mechanical, impellor-type current meters attached to a wading rod. The evaluation project has focused on three categories of hydroacoustic meters: an acoustic Doppler velocimeter (ADV) called a Flowtracker3, an acoustic Doppler velocity profiler (BoogieDopp), and bottom-tracking acoustic Doppler current profilers (ADCPs). The USGS role in this project includes providing USGS discharge-computation methods and algorithms to instrument manufacturers and evaluating instruments in the laboratory and field. An ADV (Flowtracker) designed for making discharge measurements in shallow rivers, has been tested in a USGS tow tank and was found to meet USGS calibration standards for mechanical, impellor-type current meters. The Flowtracker was field tested by USGS offices in five states; the tests were conducted by comparing discharge measurements made with the ADV to discharge measurements made with mechanical, impellor-type current meters. In general, the comparisons of Flowtracker performance to mechanical-meter results were favorable. An acoustic Doppler velocity profiler (BoogieDopp) is being evaluated for making discharge measurements in shallow rivers. The Boogiedopp will measure vertical velocity profiles at stationary positions across a channel, and the velocity profiles will be used to compute discharge. Discharge-computation software based on USGS methods and algorithms is under development for the acoustic Doppler velocity profiler. The USGS will evaluate bottom-tracking ADCPs from two manufacturers for making discharge measurements in shallow water. The bottom-tracking feature allows ADCPs to compute discharge from a moving platform as the platform moves across the channel.

  5. High resolution synoptic salinity mapping to identify groundwater--surface water discharges in lowland rivers.

    PubMed

    Pai, Henry; Villamizar, Sandra R; Harmon, Thomas C

    2015-04-21

    Quantifying distributed lateral groundwater contributions to surface water (GW-SW discharges) is a key aspect of tracking nonpoint-source pollution (NPSP) within a watershed. In this study, we characterized distributed GW-SW discharges and associated salt loading using elevated GW specific conductance (SC) as a tracer along a 38 km reach of the Lower Merced River in Central California. High resolution longitudinal surveys for multiple flows (1.3-150 m(3) s(-1)) revealed river SC gradients that mainly decreased with increasing flow, suggesting a dilution effect and/or reduced GW-SW discharges due to hydraulic gradient reductions. However, exceptions occurred (gradients increasing with increasing flow), pointing to complex spatiotemporal influences on GW-SW dynamics. The surveys revealed detailed variability in salinity gradients, from which we estimated distributed GW-SW discharge and salt loading using a simple mixing model. Modeled cumulative GW discharges for two surveys unaffected by ungauged SW discharges were comparable in magnitude to differential gauging-based discharge estimates and prior GW-SW studies along the same river reach. Ungauged lateral inlets and sparse GW data limited the study, and argue for enhancing monitoring efforts. Our approach provides a rapid and economical method for characterizing NPSP for gaining rivers in the context of integrated watershed modeling and management.

  6. Wastewater discharge impact on drinking water sources along the Yangtze River (China).

    PubMed

    Wang, Zhuomin; Shao, Dongguo; Westerhoff, Paul

    2017-12-01

    Unplanned indirect (de facto) wastewater reuse occurs when wastewater is discharged into surface waters upstream of potable drinking water treatment plant intakes. This paper aims to predict percentages and trends of de facto reuse throughout the Yangtze River watershed in order to understand the relative contribution of wastewater discharges into the river and its tributaries towards averting water scarcity concerns. The Yangtze River is the third longest in the world and supports more than 1/15 of the world's population, yet the importance of wastewater on the river remains ill-defined. Municipal wastewater produced in the Yangtze River Basin increased by 41% between 1998 and 2014, from 2580m(3)/s to 3646m(3)/s. Under low flow conditions in the Yangtze River near Shanghai, treated wastewater contributions to river flows increased from 8% in 1998 to 14% in 2014. The highest levels of de facto reuse appeared along a major tributary (Han River) of the Yangtze River, where de facto reuse can exceed 20%. While this initial analysis of de facto reuse used water supply and wastewater data from 110 cities in the basin and 11 gauging stations with >50years of historic streamflow data, the outcome was limited by the lack of gauging stations at more locations (i.e., data had to be predicted using digital elevation mapping) and lack of precise geospatial location of drinking water intakes or wastewater discharges. This limited the predictive capability of the model relative to larger datasets available in other countries (e.g., USA). This assessment is the first analysis of de facto wastewater reuse in the Yangtze River Basin. It will help identify sections of the river at higher risk for wastewater-related pollutants due to presence of-and reliance on-wastewater discharge that could be the focus of field studies and model predictions of higher spatial and temporal resolution. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Spatiotemporal interpolation of discharge across a river network by using synthetic SWOT satellite data

    NASA Astrophysics Data System (ADS)

    Paiva, Rodrigo C. D.; Durand, Michael T.; Hossain, Faisal

    2015-01-01

    Recent efforts have sought to estimate river discharge and other surface water-related quantities using spaceborne sensors, with better spatial coverage but worse temporal sampling as compared with in situ measurements. The Surface Water and Ocean Topography (SWOT) mission will provide river discharge estimates globally from space. However, questions on how to optimally use the spatially distributed but asynchronous satellite observations to generate continuous fields still exist. This paper presents a statistical model (River Kriging-RK), for estimating discharge time series in a river network in the context of the SWOT mission. RK uses discharge estimates at different locations and times to produce a continuous field using spatiotemporal kriging. A key component of RK is the space-time river discharge covariance, which was derived analytically from the diffusive wave approximation of Saint Venant's equations. The RK covariance also accounts for the loss of correlation at confluences. The model performed well in a case study on Ganges-Brahmaputra-Meghna (GBM) River system in Bangladesh using synthetic SWOT observations. The correlation model reproduced empirically derived values. RK (R2=0.83) outperformed other kriging-based methods (R2=0.80), as well as a simple time series linear interpolation (R2=0.72). RK was used to combine discharge from SWOT and in situ observations, improving estimates when the latter is included (R2=0.91). The proposed statistical concepts may eventually provide a feasible framework to estimate continuous discharge time series across a river network based on SWOT data, other altimetry missions, and/or in situ data.

  8. Predicting River Discharge Rates in California Watersheds of the Russian River and Other North Coast River Basins

    NASA Astrophysics Data System (ADS)

    Shupe, J.; Potter, C. S.; Gross, P. M.; Genovese, V. B.; Klooster, S. A.

    2010-12-01

    This study describes applications of the Carnegie-Ames-Stanford Approach (CASA) ecosystem model coupled with a surface hydrologic routing scheme previously called the Hydrological Routing Algorithm (HYDRA) to model river discharge rates across selected California watersheds in the North Coast region of the state. For mountainous areas, CASA-HYDRA snowmelt algorithms have been modified with equations from the USDA Snowmelt Runoff Model (SRM), which has been refined to predict daily stream flow in mountain basins where snowmelt is a notable runoff factor. Results show that, based on CASA-HYDRA model predictions of monthly flow rates across the ten complete stream gauges in the Russian River basin from 2000 to 2007, the typical model-to-measurement correlation between monthly river flow rates was R squared = 0.76 (with E = 0.61). Similar validation results for seasonal and annual flow predictions have been developed for numerous coastal redwood forest watersheds where streams support critical wild fisheries habitat. Future model applications for land cover and climate change in northern California’s coastal watersheds are outlined, with emphasis on impacts of municipal and agricultural water demands.

  9. Convective heat discharge of Wood River group of springs in the vicinity of Crater Lake, Oregon

    USGS Publications Warehouse

    Nathenson, Manuel; Mariner, Robert H.; Thompson, J. Michael

    1994-01-01

    Data sets for spring and stream chemistry are combined to estimate convective heat discharge and discharge anomalous amounts of sodium and chloride for the Wood River group of springs south of Crater Lake. The best estimate of heat discharge is 87 MWt based on chloride inventory; this value is 3-5 times the heat input to Crater Lake itself. Anomalous discharges of sodium and chloride are also larger that into Crater Lake. Difference between the chemical and thermal characteristics of the discharge into Crater Lake and those from the Wood River group of springs suggest that the heat sources for the two systems may be different, although both ultimately related to the volcanic system.

  10. Discharge Estimation Using Satellite Gravity During Flood Seasons at the Óbidos Gauge Station, Amazon River

    NASA Astrophysics Data System (ADS)

    Eom, J.; Seo, K. W.; Lee, Y. K.

    2014-12-01

    Reliable measurement of river discharge is important for management of water resource and understanding of hydrological cycles particularly associated with global and regional climate changes. Practically, to obtain continuous time series of river discharge, regression analysis of an empirical relationship between accumulated water level and discharge data is used. During wet season, however, the relationship includes more uncertainty due to the difficulty of accurate discharge measurement. This is particularly true for the Amazon River because significant amount of water flows outside river channel during flooding. For an alternative way to estimate river discharge, we use GRACE time-varying gravity measurement from January 2003 to December 2012. We first apply Empirical Orthogonal Function (EOF) for GRACE time-varying gravity fields in Amazon and successfully isolate gravity signal in the main stream. The EOF time series represents relative river discharge variations without larger uncertainty during flooding season compared to conventional in-situ discharge estimate. Estimates of Amazon River discharge based on GRACE data are very close to those from observed at gauge stations during dry seasons. However, our estimates are larger than in-situ data in high water seasons, and the difference is the maximum at the 2009 flooding. This is probably because in-situ observation underestimates river discharge during wet season due possibly to detoured water in river pathway developed during flooding while GRACE observes integrated water mass variations in river channels.

  11. Assessment of coal geology, resources, and reserves in the Southwestern Powder River Basin, Wyoming

    USGS Publications Warehouse

    Osmonson, Lee M.; Scott, David C.; Haacke, Jon E.; Luppens, James A.; Pierce, Paul E.

    2011-01-01

    A total of 37 coal beds were identified during this assessment, 23 of which were modeled and evaluated to determine in-place coal resources. The total original coal resource in the Southwestern Powder River Basin assessment area for these 23 coal beds, with no restrictions applied was calculated to be 369 billion short tons. Available coal resources, which are part of the original resource that is accessible for potential mine development after subtracting all restrictions, are about 341 billion short tons (92.4 percent of the total original resource). Approximately 61 percent are at depths between 1,000 and 2,000 ft, with a modeled price of about $30 per short ton. Therefore, the majority of coal resources in the South-western Powder River Basin assessment area are considered sub-economic.

  12. Toward global mapping of river discharge using satellite images and at-many-stations hydraulic geometry

    PubMed Central

    Gleason, Colin J.; Smith, Laurence C.

    2014-01-01

    Rivers provide critical water supply for many human societies and ecosystems, yet global knowledge of their flow rates is poor. We show that useful estimates of absolute river discharge (in cubic meters per second) may be derived solely from satellite images, with no ground-based or a priori information whatsoever. The approach works owing to discovery of a characteristic scaling law uniquely fundamental to natural rivers, here termed a river’s at-many-stations hydraulic geometry. A first demonstration using Landsat Thematic Mapper images over three rivers in the United States, Canada, and China yields absolute discharges agreeing to within 20–30% of traditional in situ gauging station measurements and good tracking of flow changes over time. Within such accuracies, the door appears open for quantifying river resources globally with repeat imaging, both retroactively and henceforth into the future, with strong implications for water resource management, food security, ecosystem studies, flood forecasting, and geopolitics. PMID:24639551

  13. Sediment discharge into a subsiding Louisiana deltaic estuary through a Mississippi River diversion

    USGS Publications Warehouse

    Snedden, G.A.; Cable, J.E.; Swarzenski, C.; Swenson, E.

    2007-01-01

    Wetlands of the Mississippi River deltaic plain in southeast Louisiana have been hydrologically isolated from the Mississippi River by containment levees for nearly a century. The ensuing lack of fluvial sediment inputs, combined with natural submergence processes, has contributed to high coastal land loss rates. Controlled river diversions have since been constructed to reconnect the marshes of the deltaic plain with the river. This study examines the impact of a pulsed diversion management plan on sediment discharge into the Breton Sound estuary, in which duplicate 185 m3 s-1-diversions lasting two weeks each were conducted in the spring of 2002 and 2003. Sediment delivery during each pulse was highly variable (11,300-43,800 metric tons), and was greatest during rising limbs of Mississippi River flood events. Overland flow, a necessary transport mechanism for river sediments to reach the subsiding backmarsh regions, was induced only when diversion discharge exceeded 100 m3 s-1. These results indicate that timing and magnitude of diversion events are both important factors governing marsh sediment deposition in the receiving basins of river diversions. Though the diversion serves as the primary source of river sediments to the estuary, the inputs observed here were several orders of magnitude less than historical sediment discharge through crevasses and uncontrolled diversions in the region, and are insufficient to offset present rates of relative sea level rise. ?? 2006 Elsevier Ltd. All rights reserved.

  14. Sediment discharge into a subsiding Louisiana deltaic estuary through a Mississippi River diversion

    NASA Astrophysics Data System (ADS)

    Snedden, Gregg A.; Cable, Jaye E.; Swarzenski, Christopher; Swenson, Erick

    2007-01-01

    Wetlands of the Mississippi River deltaic plain in southeast Louisiana have been hydrologically isolated from the Mississippi River by containment levees for nearly a century. The ensuing lack of fluvial sediment inputs, combined with natural submergence processes, has contributed to high coastal land loss rates. Controlled river diversions have since been constructed to reconnect the marshes of the deltaic plain with the river. This study examines the impact of a pulsed diversion management plan on sediment discharge into the Breton Sound estuary, in which duplicate 185 m 3 s -1-diversions lasting two weeks each were conducted in the spring of 2002 and 2003. Sediment delivery during each pulse was highly variable (11,300-43,800 metric tons), and was greatest during rising limbs of Mississippi River flood events. Overland flow, a necessary transport mechanism for river sediments to reach the subsiding backmarsh regions, was induced only when diversion discharge exceeded 100 m 3 s -1. These results indicate that timing and magnitude of diversion events are both important factors governing marsh sediment deposition in the receiving basins of river diversions. Though the diversion serves as the primary source of river sediments to the estuary, the inputs observed here were several orders of magnitude less than historical sediment discharge through crevasses and uncontrolled diversions in the region, and are insufficient to offset present rates of relative sea level rise.

  15. Possible impact of treated wastewater discharge on incidence of antibiotic resistant bacteria in river water.

    PubMed

    Iwane, T; Urase, T; Yamamoto, K

    2001-01-01

    Escherichia coli and coliform group bacteria resistant to seven antibiotics were investigated in the Tama River, a typical urbanized river in Tokyo, Japan, and at a wastewater treatment plant located on the river. The percentages of antibiotic resistance in the wastewater effluent were, in most cases, higher than the percentages in the river water, which were observed increasing downstream. Since the possible increase in the percentages in the river was associated with treated wastewater discharges, it was concluded that the river, which is contaminated by treated wastewater with many kinds of pollutants, is also contaminated with antibiotic resistant coliform group bacteria and E. coli. The percentages of resistant bacteria in the wastewater treatment plant were mostly observed decreasing during the treatment process. It was also demonstrated that the percentages of resistance in raw sewage are significantly higher than those in the river water and that the wastewater treatment process investigated in this study works against most of resistant bacteria in sewage.

  16. Regional thermal-inertia mapping from an experimental satellite ( Powder River basin, Wyoming).

    USGS Publications Warehouse

    Watson, K.

    1982-01-01

    A new experimental satellite has provided, for the first time, thermal data that should be useful in reconnaissance geologic exploration. Thermal inertia, a property of geologic materials, can be mapped from these data by applying an algorithm that has been developed using a new thermal model. A simple registration procedure was used on a pair of day and night images of the Powder River basin, Wyoming, to illustrate the method.-from Author

  17. Estimated monthly percentile discharges at ungaged sites in the Upper Yellowstone River Basin in Montana

    USGS Publications Warehouse

    Parrett, Charles; Hull, J.A.

    1986-01-01

    Once-monthly streamflow measurements were used to estimate selected percentile discharges on flow-duration curves of monthly mean discharge for 40 ungaged stream sites in the upper Yellowstone River basin in Montana. The estimation technique was a modification of the concurrent-discharge method previously described and used by H.C. Riggs to estimate annual mean discharge. The modified technique is based on the relationship of various mean seasonal discharges to the required discharges on the flow-duration curves. The mean seasonal discharges are estimated from the monthly streamflow measurements, and the percentile discharges are calculated from regression equations. The regression equations, developed from streamflow record at nine gaging stations, indicated a significant log-linear relationship between mean seasonal discharge and various percentile discharges. The technique was tested at two discontinued streamflow-gaging stations; the differences between estimated monthly discharges and those determined from the discharge record ranged from -31 to +27 percent at one site and from -14 to +85 percent at the other. The estimates at one site were unbiased, and the estimates at the other site were consistently larger than the recorded values. Based on the test results, the probable average error of the technique was + or - 30 percent for the 21 sites measured during the first year of the program and + or - 50 percent for the 19 sites measured during the second year. (USGS)

  18. Estimates of River Discharge to the Arctic Ocean and Northern Seas

    NASA Astrophysics Data System (ADS)

    Lammers, R. B.; Shiklomanov, A. I.; Rawlins, M. A.; Vorosmarty, C. J.; Fekete, B. M.

    2004-05-01

    Several estimates of pan-Arctic freshwater flux to the ocean are made using observed river discharge data, modeled results, and a composite of the two. For observed data we report on an updated version of the R-ArcticNet river discharge database. This database now contains over 5000 gauges from Alaska, Canada, Scandinavia, and Russia. Modeled results use the Permafrost Water Balance Model (P/WBM) to characterize runoff, and other key hydrological variables, throughout the pan-Arctic region. The composite runoff field uses a hybrid of the observed data and modeled results to provide a "best guess" river discharge estimate. All estimates are carried out using the 25 km resolution digital river network based on the NSIDC Northern Hemisphere EASE grid. This river network contains over 3089 drainage basins within 18 Sea Basins throughout the pan-Arctic drainage system. An intercomparison of the different methods of estimating discharge to the ocean provides us with a range in expected outcomes which will yield those regions with increased uncertainty in discharge. The resultant database will be of use to Arctic Ocean modelers and those interested in the flux of freshwater continental shelves in the Arctic Seas.

  19. Low-Flow Characteristics and Mean Annual Discharge of North Branch Manitowoc River at Potter, Wisconsin

    USGS Publications Warehouse

    Holmstrom, B.K.

    1976-01-01

    The low-flow characteristics presented in this report are the annual minimum 7-day mean flows at the 2-year recurrence interval and 10-year recurrence interval. They were determined just downstream from the confluence of the three streams forming the North Branch Manitowoc River and, based on natural-flow conditions, are 0.0 cubic foot per second (0.0 cubic metre per second). Observations made in October 1974 showed that the natural discharge of the three streams forming the North Branch Manitowoc River was 0.0 cubic foot per second (0.0 cubic metre per second). A discharge of 0.30 cubic foot per second (0.008 cubic metre per second) was measured in the tributary from Hilbert but this was predominantly effluent from the sewage-treatment plant and a cheese factory in Hilbert. The mean annual discharge for the North Branch Manitowoc River at Potter is 27 cubic feet per second (0.76 cubic metre per second). This was based on the estimated and recorded discharge for June 1, 1974, to May 31, 1975, for the North Branch Manitowoc River at Potter site and an adjustment based on the long-term mean annual discharge at gaging station 04086000, Sheboygan River at Sheboygan.

  20. Reconstruction of Ob River, Russia, discharge from ring widths of floodplain trees

    NASA Astrophysics Data System (ADS)

    Agafonov, Leonid I.; Meko, David M.; Panyushkina, Irina P.

    2016-12-01

    The Ob is the third largest Eurasian river supplying heat and freshwater to the Arctic Ocean. These inputs influence water salinity, ice coverage, ocean temperatures and ocean circulation, and ultimately the global climate system. Variability of Ob River flow on long time scales is poorly understood, however, because gaged flow records are short. Eleven tree-ring width chronologies of Pinus sibirica and Larix sibirica are developed from the floodplain of the Lower Ob River, analyzed for hydroclimatic signal and applied as predictors in a regression model to reconstruct 8-month average (December-July) discharge of the Ob River at Salekhard over the interval 1705-2012 (308 yrs). Correlation analysis suggests the signal for discharge comes through air temperature: high discharge and floodplain water levels favor cool growing-season air temperature, which limits tree growth for the sampled species at these high latitudes. The reconstruction model (R2 = 0.31, 1937-2009 calibration period) is strongly supported by cross-validation and analysis of residuals. Correlation of observed with reconstructed discharge improves with smoothing. The long-term reconstruction correlates significantly with a previous Ob River reconstruction from ring widths of trees outside the Ob River floodplain and extends that record by another century. Results suggest that large multi-decadal swings in discharge have occurred at irregular intervals, that variations in the 20th and 21st centuries have been within the envelope of natural variability of the past 3 centuries, and that discharge data for 1937-2009 underestimate both the variability and persistence of discharge in the last 3 centuries. The reconstruction gives ecologists, climatologists and water resource planners a long-term context for assessment of climate change impacts.

  1. Hyperpycnal sediment discharge from semiarid southern California rivers: Implications for coastal sediment budgets

    USGS Publications Warehouse

    Warrick, J.A.; Milliman, John D.

    2003-01-01

    Southern California rivers discharge hyperpycnal (river density greater than ocean density) concentrations of suspended sediment (>40 g/L, according to buoyancy theory) during flood events, mostly during El Nin??o-Southern Oscillation (ENSO) conditions. Because hyperpycnal river discharge commonly occurs during brief periods (hours to occasionally days), mean daily flow statistics often do not reveal the magnitude of these events. Hyperpycnal events are particularly important in rivers draining the Transverse Range and account for 75% of the cumulative sediment load discharged by the Santa Clara River over the past 50 yr. These events are highly pulsed, totaling only ??? 30 days (??? 0.15% of the total 50 yr period). Observations of the fate of sediment discharge, although rare, are consistent with hyperpycnal river dynamics and the high likelihood of turbidity currents during these events. We suggest that much of the sediment load initially bypasses the littoral circulation cells and is directly deposited on the adjacent continental shelf, thus potentially representing a loss of immediate beach sand supply. During particularly exceptional events (>100 yr recurrence intervals), flood underflows may extend past the shelf and escape to offshore basins.

  2. Estimating river discharge using multiple-tide gauges distributed along a channel

    NASA Astrophysics Data System (ADS)

    Moftakhari, H. R.; Jay, D. A.; Talke, S. A.

    2016-04-01

    Reliable estimation of freshwater inflow to the ocean from large tidal rivers is vital for water resources management and climate analyses. Discharge gauging stations are typically located beyond the tidal intrusion reach, such that inputs and losses occurring closer to the ocean are not included. Here, we develop a method of estimating river discharge using multiple gauges and time-dependent tidal statistics determined via wavelet analysis. The Multiple-gauge Tidal Discharge Estimate (MTDE) method is developed using data from the Columbia River and Fraser River estuaries and calibrated against river discharge. Next, we evaluate the general applicability of MTDE by testing an idealized two-dimensional numerical model, with a convergent cross-sectional profile, for eighty-one cases in which nondimensional numbers for friction, river flow, and convergence length scale are varied. The simulations suggest that MTDE is applicable to a variety of tidal systems. Model results and data analyses together suggest that MTDE works best with at least three gauges: a reference station near the river mouth, and two upstream gauges that respond strongly to distinct portions of the observed range of flow. The balance between tidal damping and amplifying factors determines the favorable location of the gauges. Compared to previous studies, the MTDE method improves the time resolution of estimates (from 2.5 to <1 week) and is applicable to systems with mixed diurnal/semidiurnal tides. However, model results suggest that tide-induced residual flows such as the Stokes drift may still affect the accuracy of MTDE at seaward locations during periods of low river discharge.

  3. Effects of river discharge on hyporheic exchange flows in salmon spawning areas of a large gravel-bed river

    SciTech Connect

    Hanrahan, Timothy P.

    2008-01-01

    The flow magnitude and timing from hydroelectric dams in the Snake River basin of the Pacific northwestern United States is managed in part for the benefit of salmon. The objective of this research was to evaluate the effects of current Hells Canyon Dam discharge operations on hydrologic exchange flows between the river and riverbed in Snake River fall Chinook salmon spawning areas. Interactions between river water and pore water within the upper 1 m of the riverbed were quantified through the use of self-contained temperature and water level data loggers suspended inside of piezometers. The data were recorded at 20 min intervals over a period of 200 days when the mean daily discharge was 218–605 m3 s–1, with hourly stage changes as large as 1.9 m. Differences in head pressure between the river and riverbed were small, often within ±2 cm. Measured temperature gradients in the riverbed indicated significant interactions between the surface and subsurface water. Neither hydraulic nor temperature gradients at most sites were significantly affected by either short- or long-term changes in discharge operations from Hells Canyon Dam. Only 2 out of 14 study sites exhibited acute flux reversals between the river and riverbed resulting from short-term, large magnitude changes in discharge. The findings suggest small-scale piezometric head differences play a minor role in the hydrologic exchange between the river and riverbed at the study sites. The processes controlling hydrologic exchange at the study sites are likely to be bedform-induced advective pumping, turbulence at the riverbed surface, and large-scale hydraulic gradients along the longitudinal profile of the riverbed. By incorporating the knowledge of hydrologic exchange processes into water management planning, regional agencies will be better prepared to manage the limited water resources among competing priorities that include salmon recovery, flood control, irrigation supply, hydropower production, and

  4. Multi-scale analysis of the fluxes between terrestrial water storage, groundwater, and stream discharge in the Columbia River Basin

    EPA Science Inventory

    The temporal relationships between the measurements of terrestrial water storage (TWS), groundwater, and stream discharge were analyzed at three different scales in the Columbia River Basin (CRB) for water years 2004 - 2012. Our nested watershed approach examined the Snake River ...

  5. Multi-scale analysis of the fluxes between terrestrial water storage, groundwater, and stream discharge in the Columbia River Basin

    EPA Science Inventory

    The temporal relationships between the measurements of terrestrial water storage (TWS), groundwater, and stream discharge were analyzed at three different scales in the Columbia River Basin (CRB) for water years 2004 - 2012. Our nested watershed approach examined the Snake River ...

  6. Groundwater Discharges to Rivers in the Western Canadian Oil Sands Region

    NASA Astrophysics Data System (ADS)

    Ellis, J.; Jasechko, S.

    2016-12-01

    Groundwater discharges into rivers impacts the movement and fate of nutrients and contaminants in the environment. Understanding groundwater-surface water interactions is especially important in the western Canadian oil sands, where groundwater contamination risks are elevated and baseline water chemistry data is lacking, leading to substantial uncertainties about anthropogenic influences on local river quality. High salinity groundwater springs sourced from deep aquifers, comprised of Pleistocene-aged glacial meltwater, are known to discharge into many rivers in the oil sands. Understanding connections between deep aquifers and surficial waterways is important in order to determine natural inputs into these rivers and to assess the potential for injected wastewater or oil extraction fluids to enter surface waters. While these springs have been identified, their spatial distribution along rivers has not been fully characterized. Here we present river chemistry data collected along a number of major river corridors in the Canadian oil sands region. We show that saline groundwater springs vary spatially along the course of these rivers and tend to be concentrated where the rivers incise Devonian- or Cretaceous-aged aquifers along an evaporite dissolution front. Our results suggest that water sourced from Devonian aquifers may travel through bitumen-bearing Cretaceous units and discharge into local rivers, implying a strong groundwater-surface water connection in specialized locations. These findings indicate that oil sands process-affected waters that are injected at depth have the potential to move through these aquifers and reach the rivers at the surface at some time in the future. Groundwater-surface water interactions remain key to understanding the risks oil sands activities pose to aquatic ecosystems and downstream communities.

  7. Calibration of satellite measurements of river discharge using a global hydrology model

    NASA Astrophysics Data System (ADS)

    Robert Brakenridge, G.; Cohen, Sagy; Kettner, Albert J.; De Groeve, Tom; Nghiem, Son V.; Syvitski, James P. M.; Fekete, Balazs M.

    2012-12-01

    SummaryMeasurements of river discharge and watershed runoff are essential to water resources management, efficient hydropower generation, accurate flood prediction and control, and improved understanding of the global water cycle. Previous work demonstrates that orbital remote sensing can measure river discharge variation in a manner closely analogous to its measurement at ground stations, and using reach flow surface area instead of stage as the discharge estimator. For international measurements, hydrological modeling can, in principle, be used to provide the needed calibration of sensor data to discharge. The present study tests this approach and investigates the accuracy of the results. We analyze six sites within the US where gauging station, satellite measurements, and WBM model results are all available. Knowledge is thereby gained concerning how accurately satellite sensors can measure discharge, if the signal is calibrated only from global modeling results without any ground-based information. The calibration (rating) equations obtained for the remote sensing signal are similar, whether based on gauging station or on model information: r2 correlation coefficients for least squares fits at one example site (#524; White River, Indiana) are both .66 (n = 144, comparing monthly daily maxima, minima, and mean, 2003-2006). Space-based 4-day mean discharge values for this site when using the model calibration are accurate to within ±67% on the average (n = 1824; largest percent errors occur at low discharges), and annual total runoff is accurate to ±9%, 2003-2008. Comparison of gauging station versus modeled discharge commonly indicates a small positive model bias; the observed errors of satellite-observed annual runoff are also positive and could be improved by bias removal from the rating curves. Also, analysis of a large flood event, along the Indus River in 2010, shows that the model does not capture flood wave attenuation by overbank flow, and thus

  8. Enhanced Coal Bed Methane Recovery and CO2 Sequestration in the Powder River Basin

    SciTech Connect

    Eric P. Robertson

    2010-06-01

    Unminable coal beds are potentially large storage reservoirs for the sequestration of anthropogenic CO2 and offer the benefit of enhanced methane production, which can offset some of the costs associated with CO2 sequestration. The objective of this report is to provide a final topical report on enhanced coal bed methane recovery and CO2 sequestration to the U.S. Department of Energy in fulfillment of a Big Sky Carbon Sequestration Partnership milestone. This report summarizes work done at Idaho National Laboratory in support of Phase II of the Big Sky Carbon Sequestration Partnership. Research that elucidates the interaction of CO2 and coal is discussed with work centering on the Powder River Basin of Wyoming and Montana. Sorption-induced strain, also referred to as coal swelling/shrinkage, was investigated. A new method of obtaining sorption-induced strain was developed that greatly decreases the time necessary for data collection and increases the reliability of the strain data. As coal permeability is a strong function of sorption-induced strain, common permeability models were used to fit measured permeability data, but were found inadequate. A new permeability model was developed that can be directly applied to coal permeability data obtained under laboratory stress conditions, which are different than field stress conditions. The coal permeability model can be used to obtain critical coal parameters that can be applied in field models. An economic feasibility study of CO2 sequestration in unminable coal seams in the Powder River Basin of Wyoming was done. Economic analyses of CO2 injection options are compared. Results show that injecting flue gas to recover methane from CBM fields is marginally economical; however, this method will not significantly contribute to the need to sequester large quantities of CO2. Separating CO2 from flue gas and injecting it into the unminable coal zones of the Powder River Basin seam is currently uneconomical, but can

  9. Discharge ratings for control gates at Mississippi River lock and dam 21, Quincy, Illinois

    USGS Publications Warehouse

    Heinitz, A.J.

    1987-01-01

    The water levels of the navigation pools on the Mississippi River are maintained by the operation of tainter and roller gates at the locks and dams. Discharge ratings for the gates on Lock and Dam 21, at Quincy, Illinois, were developed from current meter discharge measurements made in the forebays of the gate structures. Methodology is given to compute the gate openings of the tainter gates accurately. Discharge coefficients , in equations that express discharge as a function of tailwater head, forebay head, and height of gate opening, were determined for conditions of submerged orifice and free weir flow. A comparison of the rating discharges to the hydraulic model rating discharges is given for submerged orifice flow for the tainter and roller gates.

  10. Discharge ratings for control gates at Mississippi River lock and dam 12, Bellevue, Iowa

    USGS Publications Warehouse

    Heinitz, Albert J.

    1986-01-01

    The water level of the navigation pools on the Mississippi River are maintained by the operation of tainter and roller gates at the locks and dams. Discharge ratings for the gates on Lock and Dam 12, at Bellevue, Iowa, were developed from current-meter discharge measurements made in the forebays of the gate structures. Methodology is given to accurately compute the gate openings of the tainter gates. Discharge coefficients, in equations that express discharge as a function of tailwater head , forebay head, and height of gate opening, were determined for conditions of submerged-orifice and fee-weir flow. A comparison of the rating discharges to the hydraulic-model rating discharges is given for submerged orifice flow for the tainter and roller gates.

  11. Predicting the Discharge Rate Contribution of the Binuwang Watershed to the Agos River, Philippines

    NASA Astrophysics Data System (ADS)

    Aquino, Dakila; Paningbatan, Eduardo; Mahar Francisco Lagmay, Alfredo

    2014-05-01

    In 2004, Typhoon Winnie brought torrential rains which triggered massive landslides and floods which devastated the provinces of Infanta, Real and General Nakar in the Philippines. Winnie inflicted USD 111.14 million worth of damage to crops, livestock and infrastructure and left thousands dead or homeless. The Binuwang River is a sub-tributary of the Agos River, but the extent to which it contributes to flooding has not yet been determined. This study measures the depth of the Binuwang River to estimate the discharge rate contribution of the Binuwang River Watershed to the Agos River using an automatic rain gauge recorder and water level loggers set to record at 5-minute intervals. Flood-generating rainfall events were monitored during the onset of Typhoon Nesat (locally called 'Pedring') September 26-27, 2011. The automated rain gauge recorded 227 mm cumulative rainfall over a 6-hour and 41-minute period. It reached a peak rainfall intensity of 17.5 mm per 5-minute interval that generated a discharge height increase of 1.8 m at the monitoring station and a total discharge volume of 99,823 m3 over a 35-hour duration. An 8.81-hour lag time from the peak rainfall to the peak discharge concentration was recorded. A PCRaster-based hydrologic model was used to predict the total discharge hydrograph of the Binuwang River Watershed. A Digital Elevation Model (DEM) and soil and land use maps were prepared to parameterize the model. The observed and predicted discharge hydrographs were found to be highly correlated. Among the parameters used to calibrate the model hydrologic output, most sensitive are the infiltration saturation coefficient and Manning's roughness coefficient. An increase in the infiltration saturation coefficient resulted in a decreased discharge height, while an increase of Manning's roughness coefficient lengthened the lag time. The predicted discharge volume and height were used to simulate the impact of reforestation and land conversion to cultivated

  12. Orbital forcing of Cretaceous river discharge in tropical Africa and ocean response.

    PubMed

    Beckmann, Britta; Flögel, Sascha; Hofmann, Peter; Schulz, Michael; Wagner, Thomas

    2005-09-08

    The tropics have been suggested as the drivers of global ocean and atmosphere circulation and biogeochemical cycling during the extreme warmth of the Cretaceous period; but the links between orbital forcing, freshwater runoff and the biogeochemistry of continental margins in extreme greenhouse conditions are not fully understood. Here we present Cretaceous records of geochemical tracers for freshwater runoff obtained from a sediment core off the Ivory Coast that indicate that alternating periods of arid and humid African climate were driven by orbital precession. Our simulations of the precession-driven patterns of river discharge with a global climate model suggest that ocean anoxia and black shale sedimentation were directly caused by high river discharge, and occurred specifically when the northern equinox coincided with perihelion (the minimum distance between the Sun and the Earth). We conclude that, in a warm climate, the oceans off tropical continental margins respond rapidly and sensitively to even modest changes in river discharge.

  13. On the exploitation of optical and thermal band for river discharge estimation: synergy with radar altimetry

    NASA Astrophysics Data System (ADS)

    Tarpanelli, Angelica; Filippucci, Paolo; Brocca, Luca

    2017-04-01

    River discharge is recognized as a fundamental physical variable and it is included among the Essential Climate Variables by GCOS (Global Climate Observing System). Notwithstanding river discharge is one of the most measured components of the hydrological cycle, its monitoring is still an open issue. Collection, archiving and distribution of river discharge data globally is limited, and the currently operating network is inadequate in many parts of the Earth and is still declining. Remote sensing, especially satellite sensors, have great potential in offering new ways to monitor river discharge. Remote sensing guarantees regular, uniform and global measurements for long period thanks to the large number of satellites launched during the last twenty years. Because of its nature, river discharge cannot be measured directly and both satellite and traditional monitoring are referred to measurements of other hydraulic variables, e.g. water level, flow velocity, water extent and slope. In this study, we illustrate the potential of different satellite sensors for river discharge estimation. The recent advances in radar altimetry technology offered important information for water levels monitoring of rivers even if the spatio-temporal sampling is still a limitation. The multi-mission approach, i.e. interpolating different altimetry tracks, has potential to cope with the spatial and temporal resolution, but so far few studies were dedicated to deal with this issue. Alternatively, optical sensors, thanks to their frequent revisit time and large spatial coverage, could give a better support for the evaluation of river discharge variations. In this study, we focus on the optical (Near InfraRed) and thermal bands of different satellite sensors (MODIS, MERIS, AATSR, Landsat, Sentinel-2) and particularly, on the derived products such as reflectance, emissivity and land surface temperature. The performances are compared with respect to the well-known altimetry (Envisat/Ra-2, Jason

  14. Evolution of cutoffs across meander necks in Powder River, Montana, USA

    USGS Publications Warehouse

    Gay, G.R.; Gay, H.H.; Gay, W.H.; Martinson, H.A.; Meade, R.H.; Moody, J.A.

    1998-01-01

    Over a period of several decades, gullies have been observed in various stages of forming, growing and completing the cutoff of meander necks in Powder River. During one episode of overbank flow, water flowing over the down-stream bank of the neck forms a headctu. The headcut migrates up-valley, forming a gully in its wake, until it has traversed the entire neck, cutting off the meander. The river then follows the course of the gully, which is subsequently enlarged as the river develops its new channel. The complete process usually requires several episodes of high water: in only one of the five cases described herein was a meander cutoff initiated and completed during a single large flood.

  15. Assessment of coal geology, resources, and reserves in the Montana Powder River Basin

    USGS Publications Warehouse

    Haacke, Jon E.; Scott, David C.; Osmonson, Lee M.; Luppens, James A.; Pierce, Paul E.; Gunderson, Jay A.

    2013-01-01

    The purpose of this report is to summarize geology, coal resources, and coal reserves in the Montana Powder River Basin assessment area in southeastern Montana. This report represents the fourth assessment area within the Powder River Basin to be evaluated in the continuing U.S. Geological Survey regional coal assessment program. There are four active coal mines in the Montana Powder River Basin assessment area: the Spring Creek and Decker Mines, both near Decker; the Rosebud Mine, near Colstrip; and the Absaloka Mine, west of Colstrip. During 2011, coal production from these four mines totaled approximately 36 million short tons. A fifth mine, the Big Sky, had significant production from 1969-2003; however, it is no longer in production and has since been reclaimed. Total coal production from all five mines in the Montana Powder River Basin assessment area from 1968 to 2011 was approximately 1.4 billion short tons. The Rosebud/Knobloch coal bed near Colstrip and the Anderson, Dietz 2, and Dietz 3 coal beds near Decker contain the largest deposits of surface minable, low-sulfur, subbituminous coal currently being mined in the assessment area. A total of 26 coal beds were identified during this assessment, 18 of which were modeled and evaluated to determine in-place coal resources. The total original coal resource in the Montana Powder River Basin assessment area for the 18 coal beds assessed was calculated to be 215 billion short tons. Available coal resources, which are part of the original coal resource remaining after subtracting restrictions and areas of burned coal, are about 162 billion short tons. Restrictions included railroads, Federal interstate highways, urban areas, alluvial valley floors, state parks, national forests, and mined-out areas. It was determined that 10 of the 18 coal beds had sufficient areal extent and thickness to be evaluated for recoverable surface resources ([Roland (Baker), Smith, Anderson, Dietz 2, Dietz 3, Canyon, Werner

  16. Observed river discharge changes due to hydropower operations in the Upper Mekong Basin

    NASA Astrophysics Data System (ADS)

    Räsänen, Timo A.; Someth, Paradis; Lauri, Hannu; Koponen, Jorma; Sarkkula, Juha; Kummu, Matti

    2017-02-01

    The Upper Mekong Basin is undergoing extensive hydropower development and its largest dams have recently become operational. Hydropower is built to improve the regional energy supply, but at the same time, it has considerable transboundary impacts on downstream discharge regime and further on aquatic ecosystems, riparian livelihoods and food security. Despite the transboundary significance of the impacts, there is no public information on the hydropower operations or on the already observed downstream discharge impacts since the completion of the largest dams. Therefore, in this study we assess the discharge changes using observed river discharge data and a distributed hydrological model over the period of 1960-2014. Our findings indicate that the hydropower operations have considerably modified the river discharges since 2011 and the largest changes were observed in 2014. According to observed and simulated discharges, the most notable changes occurred in northern Thailand (Chiang Saen) in March-May 2014 when the discharge increased by 121-187% and in July-August 2014 when the discharge decreased by 32-46% compared to average discharges. The respective changes in Cambodia (Kratie) were 41-74% increase in March-May 2014 and 0-6% decrease in July-August 2014 discharges. The earlier model-based predictions of the discharge changes are well in line with the observed changes, although observed changes are partly larger. The discharge impacts are expected to vary from year to year depending on hydropower operations. Altogether, the results highlight the need for strong transboundary cooperation for managing the downstream impacts.

  17. Effects of Mackenzie River Discharge and Bathymetry on Sea Ice in the Beaufort Sea

    NASA Technical Reports Server (NTRS)

    Nghiem, S. V.; Hall, D. K.; Rigor, I. G; Li, P.; Neumann, G.

    2014-01-01

    Mackenzie River discharge and bathymetry effects on sea ice in the Beaufort Sea are examined in 2012 when Arctic sea ice extent hit a record low. Satellite-derived sea surface temperature revealed warmer waters closer to river mouths. By 5 July 2012, Mackenzie warm waters occupied most of an open water area about 316,000 sq km. Surface temperature in a common open water area increased by 6.5 C between 14 June and 5 July 2012, before and after the river waters broke through a recurrent landfast ice barrier formed over the shallow seafloor offshore the Mackenzie Delta. In 2012, melting by warm river waters was especially effective when the strong Beaufort Gyre fragmented sea ice into unconsolidated floes. The Mackenzie and other large rivers can transport an enormous amount of heat across immense continental watersheds into the Arctic Ocean, constituting a stark contrast to the Antarctic that has no such rivers to affect sea ice.

  18. Runoff properties of extreme discharges on Paraná and Uruguay rivers

    NASA Astrophysics Data System (ADS)

    Vargas, W.; Bischoff, S.; Naumann, G.; Marcuzzi, E.

    2010-05-01

    Climate variability in different spatial scales is a study area which has reached interest in application, especially during de last years. River discharges can be considered as a robust integrator of the properties of the basin; under these premises the goal of this work is to analyse flows from the Paraná and Uruguay rivers in several gauge stations and study the behavior of positive and negative anomalies and their extremes. The variable to be analysed was defined as the number of anomalies with the same sign per year. Results show that the structures are different for both rivers, which implies a different stochastic process. Identical representativeness was found between the anomaly series in each river. The risk estimation of extremes in both rivers indicates that it is possible to establish a decision model. Additionally, the series of annual number of anomalies presented a climatic jump in the seventies, for both rivers.

  19. Prediction of mean monthly river discharges in Colombia through Empirical Mode Decomposition

    NASA Astrophysics Data System (ADS)

    Carmona, A. M.; Poveda, G.

    2015-04-01

    The hydro-climatology of Colombia exhibits strong natural variability at a broad range of time scales including: inter-decadal, decadal, inter-annual, annual, intra-annual, intra-seasonal, and diurnal. Diverse applied sectors rely on quantitative predictions of river discharges for operational purposes including hydropower generation, agriculture, human health, fluvial navigation, territorial planning and management, risk preparedness and mitigation, among others. Various methodologies have been used to predict monthly mean river discharges that are based on "Predictive Analytics", an area of statistical analysis that studies the extraction of information from historical data to infer future trends and patterns. Our study couples the Empirical Mode Decomposition (EMD) with traditional methods, e.g. Autoregressive Model of Order 1 (AR1) and Neural Networks (NN), to predict mean monthly river discharges in Colombia, South America. The EMD allows us to decompose the historical time series of river discharges into a finite number of intrinsic mode functions (IMF) that capture the different oscillatory modes of different frequencies associated with the inherent time scales coexisting simultaneously in the signal (Huang et al. 1998, Huang and Wu 2008, Rao and Hsu, 2008). Our predictive method states that it is easier and simpler to predict each IMF at a time and then add them up together to obtain the predicted river discharge for a certain month, than predicting the full signal. This method is applied to 10 series of monthly mean river discharges in Colombia, using calibration periods of more than 25 years, and validation periods of about 12 years. Predictions are performed for time horizons spanning from 1 to 12 months. Our results show that predictions obtained through the traditional methods improve when the EMD is used as a previous step, since errors decrease by up to 13% when the AR1 model is used, and by up to 18% when using Neural Networks is combined with the

  20. Effect of the river discharge implementation in an operational model for the West Iberia coastal area.

    NASA Astrophysics Data System (ADS)

    Campuzano, Francisco; Brito, David; Juliano, Manuela; Fernandes, Rodrigo; Neves, Ramiro

    2015-04-01

    In the Iberian Peninsula, most of the largest rivers discharge on the Atlantic coast draining almost two thirds of the territory. It is an important source of nutrients and sediments to these coastal areas. Rivers discharges in the Atlantic area when compared with the ones in the Mediterranean side present the particularity that their water before is released into the ocean is previously mixed in their estuaries in a different ratio depending of the estuarine residence time and the discharged flow. In order to evaluate the relative importance of the inland waters in the circulation patterns of Western Iberia, the rivers discharges were implemented in the PCOMS model application (Portuguese Coast Operational Modelling System). To reproduce the water continuum including the different spatial and temporal scales, a methodology consisting in a system of integrated models using the Mohid model was designed. At the watershed level, the Mohid Land model calculated operationally water flow and properties, including nutrients, for the main river catchments of Western Iberian with a 2 km horizontal resolution. Downstream, several operational hydrodynamic and biological estuarine applications used those outcomes as model inputs, filling the gaps in the observation network. From the estuarine models, the tidally modulated water and properties fluxes to the coast were obtained. These fluxes were finally imposed in the Portuguese Coast Operational Modelling System (PCOMS), a fully 3D baroclinic hydrodynamic and ecological regional model that covers the Iberian Atlantic front. The fate of the rivers discharges were analysed by integrating model results in boxes, comparing the climatologies obtained with and without rivers and the rivers area of influence was obtained by lagrangian tracers simulations.

  1. Meteorological, water-temperature, and discharge data for the Mattole River basin, Humboldt County, California

    USGS Publications Warehouse

    Noble, R.D.; Jackman, Alan P.

    1983-01-01

    To overcome a major difficulty in the testing of the validity of river-temperature models - the lack of adequate precise synoptic data for an entire river basin - synoptic meteorologic, water-temperature, and discharge data were obtained in the Mattole River Basin in northern California during the period June 10 through August 31, 1975. The variables monitored were water temperature in the main channel and major tributaries, wind velocity, wet-bulb and dry-bulb air temperature, total hemispherical incoming radiation, total incoming shortwave radiation, discharge in the main channel and major tributaries, and average velocity and axial dispersion coefficients in the main channel. This report describes the experimental design and the instrumentation and procedures followed to insure the best possible information, and it presents a detailed set of data which can be used in testing river-temperature models. (USGS)

  2. Discharge, gage height, and elevation of 100-year floods in the Hudson River basin, New York

    USGS Publications Warehouse

    Archer, Roger J.

    1978-01-01

    The flood discharge that may be expected to be equaled or exceeded on the average of once in 100 years (100-year flood) was computed by the log-Pearson Type-III frequency relation for 72 stations in the Hudson River basin. These discharges and, where available, their corresponding gage height and elevation above mean sea level are presented in tabular form. A short explanation of computation methods is included. The data are to be used as part of a federally funded study of the water resources and related land resources of the Hudson River basin. (Woodard-USGS)

  3. Chronic toxicity evaluation of the Savannah River Site DETF discharges and three locations on Tims Branch

    SciTech Connect

    Not Available

    1990-10-01

    Chronic toxicity tests with Ceriodaphnia dubia were conducted June 6--August 1, 1990, on the Savannah River Site M-Area supernate discharge effluent (M-004), the A-014 effluent discharge with and without DETF process flow, and for stream samples collected in Tims Branch upstream and downstream from A-014. A secondary objective of the study was to determine what DETF flow rate would not cause instream impact to the aquatic community. 2 figs., 68 tabs.

  4. Revising time series of the Elbe river discharge for flood frequency determination at gauge Dresden

    NASA Astrophysics Data System (ADS)

    Bartl, S.; Schümberg, S.; Deutsch, M.

    2009-11-01

    The German research programme RIsk MAnagment of eXtreme flood events has accomplished the improvement of regional hazard assessment for the large rivers in Germany. Here we focused on the Elbe river at its gauge Dresden, which belongs to the oldest gauges in Europe with officially available daily discharge time series beginning on 1 January 1890. The project on the one hand aimed to extend and to revise the existing time series, and on the other hand to examine the variability of the Elbe river discharge conditions on a greater time scale. Therefore one major task were the historical searches and the examination of the retrieved documents and the contained information. After analysing this information the development of the river course and the discharge conditions were discussed. Using the provided knowledge, in an other subproject, a historical hydraulic model was established. Its results then again were used here. A further purpose was the determining of flood frequency based on all pre-processed data. The obtained knowledge about historical changes was also used to get an idea about possible future variations under climate change conditions. Especially variations in the runoff characteristic of the Elbe river over the course of the year were analysed. It succeeded to obtain a much longer discharge time series which contain fewer errors and uncertainties. Hence an optimized regional hazard assessment was realised.

  5. Nature of natural gas in anomalously thick coal beds, Powder River basin, Wyoming

    SciTech Connect

    Rice, D.D.; Flores, R.M. )

    1989-09-01

    Anomalously thick coal beds (as much as 250 ft thick) occur in the Paleocene Tongue River Member of the Fort Union Formation in the Powder River basin, Wyoming. These laterally discontinuous coal beds were deposited in raised, ombrotrophic peat bogs of fluvial environments. The coal beds include the Anderson-Canyon, Wyodak-Anderson, and Big George zones in the Powder River-Recluse area, Gillette area, and central part of the basin, respectively. The coal resources in these areas are approximately 155 billion short tons. The average maceral composition of the coals is 88% huminite (vitrinite), 5% liptinite, and 7% inertinite. The coals vary in rank from subbituminous C to A (R{sub 0} values of 0.4 to 0.5%). Natural gas desorbed and produced from the coal beds and adjacent sandstones is composed mainly of methane with lesser amounts of CO{sub 2} (less than 10%). The methane is isotopically light ({delta}{sup 13}C{sup 1} values of {minus}56.7 to {minus}60.9%). Based on the chemical and isotopic composition of the gases and on the low rank of the coals, the gases are interpreted to be microbial in origin: they were generated by anaerobic bacteria that broke down the coals at low temperatures, prior to the main phase of thermogenic methane generation by devolatilization. The adsorbed amounts of methane-rich microbial gas per unit of coal in the Powder River basin are relatively low compared to amounts of thermogenic coal-bed gases from other basins. However, the total coal-bed gas resource is considered to be large (as much as several trillion cubic feet) because of the vast coal resources.

  6. Numerical Modeling of Medium Term Morphological Changes at Manavgat River Mouth Due to Combined Action of Waves and River Discharges

    NASA Astrophysics Data System (ADS)

    Demirci, E.; Baykal, C.; Guler, I.

    2016-12-01

    In this study, hydrodynamic conditions due to river discharge, wave action and sea level fluctuations within a seven month period and the morphological response of the Manavgat river mouth are modeled with XBeach, a two-dimensional depth-averaged (2DH) numerical model developed to compute the natural coastal response during time-varying storm and hurricane conditions (Roelvink et al., 2010). The study area shows an active behavior on its nearshore morphology, thus, two jetties were constructed at the river mouth between years 1996-2000. Recently, Demirci et al. (2016) has studied the impacts of an excess river discharge and concurrent wave action and tidal fluctuations on the Manavgat river mouth morphology for the duration of 12 days (December 4th and 15th, 1998) while the construction of jetties were carried on. It is concluded that XBeach has presumed the final morphology fairly well with the calibrated set of input parameters. Here, the river mouth modeled at a further past date before the construction of jetties with the similar set of input parameters (between August 1st, 1995-March 8th, 1996) to reveal the drastic morphologic change near the mouth due to high river discharge and severe storms happened in a longer period of time. Wave climate effect is determined with the wave hindcasting model, W61, developed by Middle East Technical University-OERC with the NCEP-CFSR wind data as well as the sea level data. River discharge, wave and sea level data are introduced as input parameters in the XBeach numerical model and the final output morphological change is compared with the final bed level measurements. References:Demirci, E., Baykal, C., Guler, I., Ergin, A., & Sogut, E. (postponed). Numerical Modelling on Hydrodynamic Flow Conditions and Morphological Changes Using XBeach Near Manavgat River Mouth. Accepted as Oral presentation at the 35thInt. Conf. on Coastal Eng., Istanbul, Turkey. Guler, I., Ergin, A., Yalçıner, A. C., (2003). Monitoring Sediment

  7. Probability analysis of the relation of salinity to freshwater discharge in the St. Sebastian River, Florida

    USGS Publications Warehouse

    Wicklein, S.M.; Gain, W.S.

    1999-01-01

    The St. Sebastian River lies in the southern part of the Indian River basin on the east coast of Florida. Increases in freshwater discharge due to urbanization and changes in land use have reduced salinity in the St. Sebastian River and, consequently, salinity in the Indian River, affecting the commercial fishing industry. Wind, water temperature, tidal flux, freshwater discharge, and downstream salinity all affect salinity in the St. Sebastian River estuary, but freshwater discharge is the only one of these hydrologic factors which might be affected by water-management practices. A probability analysis of salinity conditions in the St. Sebastian River estuary, taking into account the effects of freshwater discharge over a period from May 1992 to March 1996, was used to determine the likelihood (probability) that salinities, as represented by daily mean specific- conductance values, will fall below a given threshold. The effects of freshwater discharge on salinities were evaluated with a simple volumetric model fitted to time series of measured specific conductance, by using nonlinear optimization techniques. Specific-conductance values for two depths at monitored sites represent stratified flow which results from differences in salt concentration between freshwater and saltwater. Layering of freshwater and saltwater is assumed, and the model is applied independently to each layer with the assumption that the water within the layer is well mixed. The model of specific conductance as a function of discharge (a salinity response model) was combined with a model of residual variation to produce a total probability model. Flow distributions and model residuals were integrated to produce a salinity distribution and determine differences in salinity probabilities as a result of changes in water-management practices. Two possible management alternatives were analyzed: stormwater detention (reducing the peak rate of discharge but not reducing the overall flow volume) and

  8. Effects of the Changjiang (Yangtze) River discharge on planktonic community respiration in the East China Sea

    NASA Astrophysics Data System (ADS)

    Chen, Chung-Chi; Shiah, Fuh-Kwo; Chiang, Kuo-Ping; Gong, Gwo-Ching; Kemp, W. Michael

    2009-03-01

    Planktonic communities tend to flourish on the western margins of the East China Sea (ECS) fueled by substrates delivered largely from the Changjiang River, the fifth largest river in the world. To study the effects of the Changjiang River discharge on planktonic community respiration (CR), physical-chemical variables and key processes were measured in three consecutive summers in the ECS. Results showed that concentrations of nitrate and Chl a, protozoan biomass, bacterial production, as well as CR in the surface water were all negatively correlated with sea surface salinity, reflecting the strong influence of river discharge on the ECS shelf ecosystem. Moreover, mean values of nitrate, Chl a concentrations, and CR rates were proportionally related to the area of Changjiang diluted water (CDW; salinity ≤31.0 practical salinity units (psu)), an index of river discharge rate. Presumably, higher river flow delivers higher nutrient concentrations which stimulate phytoplankton growth, which in turn fuels CR. CR exhibited significant monthly and interannual variability, and rates appear to be dominated by bacteria and phytoplankton. Although the plankton community was relatively productive (mean = 0.8 mg C m-2 d-1) in the CDW, the mean ratio of production to respiration was low (0.42). This suggests that the heterotrophic processes regulating CR were supported by riverine organic carbon input in addition to in situ autotrophic production.

  9. Discharge-measurement system using an acoustic Doppler current profiler with applications to large rivers and estuaries

    USGS Publications Warehouse

    Simpson, Michael R.; Oltmann, Richard N.

    1993-01-01

    Discharge measurement of large rivers and estuaries is difficult, time consuming, and sometimes dangerous. Frequently, discharge measurements cannot be made in tide-affected rivers and estuaries using conventional discharge-measurement techniques because of dynamic discharge conditions. The acoustic Doppler discharge-measurement system (ADDMS) was developed by the U.S. Geological Survey using a vessel-mounted acoustic Doppler current profiler coupled with specialized computer software to measure horizontal water velocity at 1-meter vertical intervals in the water column. The system computes discharge from water-and vessel-velocity data supplied by the ADDMS using vector-algebra algorithms included in the discharge-measurement software. With this system, a discharge measurement can be obtained by engaging the computer software and traversing a river or estuary from bank to bank; discharge in parts of the river or estuarine cross sections that cannot be measured because of ADDMS depth limitations are estimated by the system. Comparisons of ADDMS-measured discharges with ultrasonic-velocity-meter-measured discharges, along with error-analysis data, have confirmed that discharges provided by the ADDMS are at least as accurate as those produced using conventional methods. In addition, the advantage of a much shorter measurement time (2 minutes using the ADDMS compared with 1 hour or longer using conventional methods) has enabled use of the ADDMS for several applications where conventional discharge methods could not have been used with the required accuracy because of dynamic discharge conditions.

  10. Groundwater Discharge and Salinity Sources to an Impaired Major River in a Semi-Arid Coastal Region: Nueces River, Texas

    NASA Astrophysics Data System (ADS)

    Murgulet, V.; Murgulet, D.; Hay, R.

    2015-12-01

    Nueces River, an impaired stream located on the South Texas Gulf coast area, has shown water quality degradation due to to increased salinity levels in areas adjacent to the Calallen saltwater reservoir dam. This study investigates the role of submarine groundwater discharge in delivering increased salt contents to the river and how the subsurface hydrology is affected by the presence of a salt barrier (i.e. saltwater dam) which separates the tidal and non-tidal parts of the Nueces river basin. Thus, a combination of resistivity profiling and elemental and stable isotope geochemistry methods has been applied to portions of the river located downstream (tidal) and upstream (non-tidal) of the dam. Preliminary data show that salinity levels gradually increases at the river bank indicating that groundwater is likely a source of solutes to the river in the upper, non-tidal portion. The presence of vertical upwelling of conductive groundwater plumes is also revealed by marine resistivity profiles collected along the river. Different sampling during the spring and summer of 2014 show higher concentration values of major ions (i.e., calcium, magnesium, sodium, potassium, chloride, etc.) and salinity of pore water for the upstream river at several locations while it remains relatively constant for bottom- and surface water. In addition, because the groundwater and porewater have slightly lower pH values, a shift to more acidic surface water accompanied by some increases in dissolved major ion concentrations and salinity suggest that groundwater might represent a source of increased salt content in the upper portion of the river. On the other hand, downstream dissolved major ion concentrations generally decrease in pore- and bottom water from spring to summer and are correlated with decreases in salinity while surface water becomes more saline with an increase in major ions. Therefore, these preliminary data indicate different hydrology systems of the two portions of the

  11. Climate dynamics and interdecadal discharge fluctuations in the Ural River basin

    NASA Astrophysics Data System (ADS)

    Vasil'ev, D. Yu.; Sivohip, J. T.; Chibilev, A. A.

    2016-07-01

    Data gathered from the mean annual water expenditures of the Ural River basin, obtained at 15 hydrological stations over a 70-year observation period was used to analyze its water content fluctuations and the correlation of discharge oscillations with different climate indices. Based on the Morlet-6 wavelet, the method of continuous wavelet transformation was applied to reveal latent periodicities in the discharge series. To establish factors responsible for discharge cycles, a cross wavelet analysis was performed on solar activity, types of Vangengeim atmospheric circulation, and three climate indices: the Atlantic Multidecadal Oscillation, the North Atlantic Oscillation, and the Arctic Oscillation.

  12. A PCE groundwater plume discharging to a river: influence of the streambed and near-river zone on contaminant distributions.

    PubMed

    Conant, Brewster; Cherry, John A; Gillham, Robert W

    2004-09-01

    An investigation of a tetrachloroethene (PCE) groundwater plume originating at a dry cleaning facility on a sand aquifer and discharging to a river showed that the near-river zone strongly modified the distribution, concentration, and composition of the plume prior to discharging into the surface water. The plume, streambed concentration, and hydrogeology were extensively characterized using the Waterloo profiler, mini-profiler, conventional and driveable multilevel samplers (MLS), Ground Penetrating Radar (GPR) surveys, streambed temperature mapping (to identify discharge zones), drivepoint piezometers, and soil coring and testing. The plume observed in the shallow streambed deposits was significantly different from what would have been predicted based on the characteristics of the upgradient plume. Spatial and temporal variations in the plume entering the near-river zone contributed to the complex contaminant distribution observed in the streambed where concentrations varied by factors of 100 to 5000 over lateral distances of less than 1 to 3.5 m. Low hydraulic conductivity semi-confining deposits and geological heterogeneities at depth below the streambed controlled the pattern of groundwater discharge through the streambed and influenced where the plume discharged into the river (even causing the plume to spread out over the full width of the streambed at some locations). The most important effect of the near-river zone on the plume was the extensive anaerobic biodegradation that occurred in the top 2.5 m of the streambed, even though essentially no biodegradation of the PCE plume was observed in the upgradient aquifer. Approximately 54% of the area of the plume in the streambed consisted solely of PCE transformation products, primarily cis-1,2-dichloroethene (cDCE) and vinyl chloride (VC). High concentrations in the interstitial water of the streambed did not correspond to high groundwater-discharge zones, but instead occurred in low discharge zones and are

  13. Biogeochemical transport in the Loxahatchee River estuary, Florida: The role of submarine groundwater discharge

    USGS Publications Warehouse

    Swarzenski, P.W.; Orem, W.H.; McPherson, B.F.; Baskaran, M.; Wan, Y.

    2006-01-01

    The distributions of dissolved organic carbon (DOC), Ba, U, and a suite of naturally occurring radionuclides in the U/Th decay series (222Rn, 223,224,226,228Ra) were studied during high- and low-discharge conditions in the Loxahatchee River estuary, Florida to examine the role of submarine groundwater discharge in estuarine transport. The fresh water endmember of this still relatively pristine estuary may reflect not only river-borne constituents, but also those advected during active groundwater/surface water (hyporheic) exchange. During both discharge conditions, Ba concentrations indicated slight non-conservative mixing. Such Ba excesses could be attributed either to submarine groundwater discharge or particle desorption processes. Estuarine dissolved organic carbon concentrations were highest at salinities closest to zero. Uranium distributions were lowest in the fresh water sites and mixed mostly conservatively with an increase in salinity. Suspended particulate matter (SPM) concentrations were generally lowest ( 28??dpm L- 1) at the freshwater endmember of the estuary and appear to identify regions of the river most influenced by the discharge of fresh groundwater. Activities of four naturally occurring isotopes of Ra (223,224,226,228Ra) in this estuary and select adjacent shallow groundwater wells yield mean estuarine water-mass transit times of less than 1 day; these values are in close agreement to those calculated by tidal prism and tidal frequency. Submarine groundwater discharge rates to the Loxahatchee River estuary were calculated using a tidal prism approach, an excess 226Ra mass balance, and an electromagnetic seepage meter. Average SGD rates ranged from 1.0 to 3.8 ?? 105??m3 d- 1 (20-74??L m- 2 d- 1), depending on river-discharge stage. Such calculated SGD estimates, which must include both a recirculated as well as fresh water component, are in close agreement with results obtained from a first-order watershed mass balance. Average submarine

  14. Abnormal pressure, natural fractures, and prolific hydrocarbon production in Fall river Sandstone, deep Powder River basin, Wyoming

    SciTech Connect

    Sonnenberg, S.A.; Meissner, F.F.

    1986-08-01

    Prolific hydrocarbon production from the Lower Cretaceous Fall River (Dakota) sandstone occurs in several fields in the deep overpressured portion of the Powder River basin. Most of the production to date comes from Buck Draw field at depths greater than 12,000 ft (3657 m). Individual wells in the field are capable of producing more than 2000 BOPD and have cumulatively produced in excess of 1 million bbl. Production comes mainly from stratigraphic traps. The Fall River Formation consists of fluvial, deltaic, and marine sandstones. Most of the productive sandstones in the Buck Draw area are interpreted to be fluvial (point bar) in origin. This interpretation is based upon log-curve shape, mapped subsurface trends, and the vertical sequence of sedimentary structures, lithologic textures, and mineralogic composition that was observed in cores. The fluvial sandstones were deposited by a meandering river that incised through previously deposited delta-front and marine sandstones. The delta-front and marine sandstones are in transitional contact with the underlying Fuson Shale, whereas the fluvial sandstones are in erosional contact with the Fuson. The updip traps to the fluvial sandstones are clay plugs in abandoned meander loops and the less-permeable delta-front and marine sandstones.

  15. Spatio-temporal variation of water flow and sediment discharge in the Mahanadi River, India

    NASA Astrophysics Data System (ADS)

    Bastia, Fakira; Equeenuddin, Sk. Md.

    2016-09-01

    The transport of sediments by rivers to the oceans represents an important link between the terrestrial and marine ecosystem. Therefore, this work aims to study spatio-temporal variation of the sediment discharge and erosion rate in the Mahanadi river, one of the biggest rivers in India, over past three decades vis-à-vis their controlling factors. To understand the sediment load variation, the trend analysis in the time series data of rainfall, water and sediment discharge of the Mahanadi river were also attempted. The non-parametric Mann-Kendall and Sen's methods were used to determine whether there was a positive or negative trend in the time series data with their statistical significance. The occurrence of abrupt changes was detected using Pettitt test. The trend test result represents that sediment load delivered from the Mahanadi river to the global ocean has decreased sharply at the rate of 0.515 × 106 tons/year between 1980 and 2010. Water discharge and rainfall in the basin showed no significant decreasing trend except at only one tributary. The decline in sediment discharge from the basin to the Bay of Bengal is mainly due to the increase in the number of dams, which has recorded the increase from 70 to 253 during the period of 1980 to 2010. Over the past 30 years the Mahanadi river has discharged about 49.0 ± 20.5 km3 of water and 17.4 ± 12.7 × 106 tons of sediment annually to the Bay of Bengal whereas the mean erosional rate is 265 ± 125 tons/km2/year over the period of 30 years in the basin. Based on the current data (2000-2001 to 2009-2010), sediment flux and water discharge to the ocean are 12 ± 5 × 106 tons/year and 49 ± 16 km3/year respectively; and ranking Mahanadi river second in terms of water discharge and sediment flux to the ocean among the peninsular rivers in India.

  16. Integrating lateral contributions along river reaches to improve SWOT discharge estimates

    NASA Astrophysics Data System (ADS)

    Beighley, E.; Zhao, Y.; Feng, D.; Fisher, C. K.; Raoufi, R.; Durand, M. T.; David, C. H.; Lee, H.; Boone, A. A.; Cretaux, J. F.

    2016-12-01

    Understanding the potential impacts of climate and land cover change at continental to global scales with a sufficient resolution for community scale planning and management requires an improved representation of the hydrologic cycle that is possible based on existing measurement networks and current Earth system models. The Surface Water and Ocean Topography (SWOT) mission, scheduled to launch in 2021, has the potential to address this challenge by providing measurements of water surface elevation, slope and extent for rivers wider than roughly 50-100 meters at a temporal sampling frequency ranging from days to weeks. The global uniformity and space/time resolution of the proposed SWOT measurements will enable hydrologic discovery, model advancements and new applications addressing the above challenges that are not currently possible or likely even conceivable. One derived data product planned for the SWOT mission is river discharge. Although there are several discharge algorithms that perform well for a range of conditions, this effort is focused on the MetroMan discharge algorithm. For example, in MetroMan, lateral inflow assumptions have been shown to impact performance. Here, the role of lateral inflows on discharge estimate performance is investigated. Preliminary results are presented for the Ohio River Basin. Lateral inflows are quantified for SWOT-observable river reaches using surface and subsurface runoff from North American Land Data Assimilation System (NLDAS) and lateral routing in the Hillslope River Routing (HRR) model. Frequency distributions for the fraction of reach-averaged discharge resulting from lateral inflow are presented. Future efforts will integrate lateral inflow characteristics into the MetroMan discharge algorithm and quantify the potential value of SWOT measurement in flood insurance applications.

  17. The effect of Congo River freshwater discharge on Tropical Atlantic and Africa climate variability

    NASA Astrophysics Data System (ADS)

    Materia, Stefano; Gualdi, Silvio; Navarra, Antonio

    2010-05-01

    Eastern Tropical Atlantic (ETA) collects a huge quantity of freshwater due to discharge from several rivers. Every year, the Congo river alone releases 1270 km3 of freshwater into the ocean (Weldeab et al., 2007), which is the second-largest flow in the world second only to the Amazon River. This study aims to understand the role of Congo freshwater discharge in driving circulation over ETA. In particular, the effect of the secondary peak discharge at Brazzaville river station is here analysed. This maximum occurs in late spring and releases freshwater into the Gulf of Guinea (GG) during boreal summer, namely the season characterized by the greatest sea surface temperature (SST) variability in the Gulf. 50-year observations show that large peak discharge positive anomalies are preceded by anomalously high SSTs over north-eastern Tropical Atlantic, linked with wet springs over Congo river catchment. Intense freshwater amounts into the ocean provoke a water warming beginning at the African coast in May and extending over the GG during June and July. This SST anomaly is related to highly wet rainy season over western Africa. Conversely, low spring discharges are associated with noticeable positive SST anomalies over Tropical South Atlantic in winter, with maxima around 20-25° S, and warm temperatures persist through the summer. In these years, over April the African coast starts being subject to anomalously cold SSTs which extend to the GG during the succeeding months, with the coldest anomaly registered in June. Western Africa heads toward very dry summer, again suggesting a strong linkage with GG SSTs. The long-term objective of this study is a better understanding of Tropical Atlantic variability and climate variability over Africa, through the introduction of a forcing, the continental freshwater discharge, often neglected by previous studies.

  18. Stage-discharge prediction in natural rivers using an innovative approach

    NASA Astrophysics Data System (ADS)

    Maghrebi, Mahmoud F.; Ahmadi, Arash

    2017-02-01

    Determination of stage-discharge relationships in natural rivers is extremely important in flood control projects. Observational data at various stages cannot be collected simultaneously. It may take a considerable amount of time and a great deal of difficulty to collect the data required for establishing the rating curves. The main purpose of the current paper is to estimate the discharge using the concept of isovel contours with the corresponding hydro-geometric parameters of the cross sections which was first introduced by Maghrebi (2006). Although the accuracy of the contours is not very high, it is believed that when the sum of the whole cross sectional contour values is used as a single parameter in the proposed relationship the accuracy of discharge estimation is surprisingly high. A relationship based on dimensional analysis is used to interrelate the discharges at two different stages by simply using the geometrical parameters such the cross-sectional area, wetted perimeter, the width of the free surface and a quantity which is related to the summations of isovel contours. Then, the most accurate relationship that is obtained by minimization of the differences between the calculated and analytical discharges at two different stages is introduced. For verification, the results of the proposed method are compared with the observed stage-discharge data taken from the Main and Severn rivers in UK, the Tomebamba River in Ecuador and the Yangtze River in China. The results indicate the high accuracy of the proposed method such that the mean values of MAPE and NRMSE of all selected rivers do not exceed 8.7% and 0.09, respectively.

  19. Evaluation of Acoustic Doppler Current Profiler measurements of river discharge

    USGS Publications Warehouse

    Morlock, S.E.

    1996-01-01

    The standard deviations of the ADCP measurements ranged from approximately 1 to 6 percent and were generally higher than the measurement errors predicted by error-propagation analysis of ADCP instrument performance. These error-prediction methods assume that the largest component of ADCP discharge measurement error is instrument related. The larger standard deviations indicate that substantial portions of measurement error may be attributable to sources unrelated to ADCP electronics or signal processing and are functions of the field environment.

  20. An Object-Based Method for Estimation of River Discharge from Remotely-Sensed Imagery

    NASA Astrophysics Data System (ADS)

    Burgett, D. A.; Blesius, L.; Davis, J. D.

    2010-12-01

    High resolution satellite and aerial imagery of fluvial systems contain much information about planform river channel features. However, not much is known about how these forms quantitatively related to river channel process, specifically, discharge. This research explores methods for remote image-based river discharge estimation through Object-Based Image Processing (OBIA) and GIS techniques. Previous efforts in image-based discharge estimation have relied primarily on manual delineation of river features and the input of reach-averaged values of these features into statistically based models for estimation. In addition to analyzing OBIA techniques for channel feature delineation and measurement, this approach investigates techniques of discharge estimation model design, validation, and correction along a reach, utilizing variation in “standard” channel features (e.g. water surface width), along with less tangible channel feature metrics derived from OBIA. Rather than predefine the channel unit of analysis, this work also considers the accuracy of model parameters derived from a range of channel scales, from longer reach-averaged to cross-sectional. High resolution (1 m) color infrared orthoimagery from 2005 and 2009 National Agricultural Inventory Program (NAIP) of 50 river reaches (ranging in discharge from approximately 13 m3s-1 to 856 m3s-1) were utilized for this analysis. These reaches, all near United States Geological Survey (USGS) river gages in California, USA, were split randomly and evenly into 25 reaches each for model design and validation, respectively. This approach allows better isolation of error resulting from user bias in channel feature measurement, and moves toward a more precise, standardized system of measurement for remotely observable channel form.

  1. Effects of discharge of municipal waste on water quality of the lower Mississippi River

    NASA Astrophysics Data System (ADS)

    Hanor, Jeffrey S.

    1988-12-01

    The effects of discharge of municipal wastes on water quality within the lower Mississippi River below Old River have been reevaluated using published water quality data in the Louisiana reach of the river for the water years 1974 1984. A novel graphical technique has facilitated the evaluation of upriver controls on water quality and the identification of sources and sinks along the lower Mississippi. Comparison of calculated annual fluxes at different downstream monitoring stations has simplified some of the problems inherent in evaluating analyses of samples collected from different water masses during a typical sampling run. The absolute concentrations of chloride, nitrite plus nitrate, total phosphorous, dissolved oxygen, BOD, and COD are all strongly dependent on processes occurring upriver. Nonpoint influx of materials from agricultural wastes and natural plant debris may be the dominant upstream sources of N, P, BOD, and COD. Increases in chloride and phosphorous downstream within the Lower Mississippi appear to be caused by discharge of industrial wastes. Nitrogen fluxes decrease downriver, except where there is local discharge of high-N, high-P industrial waste water, possibly from fertilizer plants. Removal of N and increases in BOD may be due in part to biological uptake. High river discharge rates and efficient, natural processes of reaeration maintain high oxygen saturation levels. With the exception of an increase in bacterial count, the discharge of municipal waste into the Mississippi River in Louisiana appears to have had no significant effect on water quality, a finding consistent with the earlier U.S. Geological Survey study of Wells (1980). It would be highly desirable for future mass balance studies if existing water quality programs on the Mississippi River were to adopt a Lagrangian sampling approach.

  2. A River Discharge Model for Coastal Taiwan during Typhoon Morakot

    DTIC Science & Technology

    2012-08-01

    such as the cold dome), the interaction of the Taiwan Strait shelf jets and currents, and surface and internal tides, internal waves , and solitons [7... mountainous region in the southern half of the island [1]. During the peak of the storm, runoff from the extreme amount of precipitation led to river...southwestern sides of Taiwan than in the surrounding regions. This likely resulted from exposure of the western slopes of the mountains to sustained

  3. Joint probability of sea waves and river discharges: a case study

    NASA Astrophysics Data System (ADS)

    Viola, Francesco; Besio, Giovanni; Mentaschi, Lorenzo

    2015-04-01

    The main drivers of physical processes acting in estuarine areas are river discharge and sea waves. The first is responsible for fresh water fluxes, sediment, nutrient and pollutants transport, the second for the diffusion and for littoral dynamics. The description of phenomena evolving between the end of a river and the proximal sea area is challenging because of the difference in water stage, salinity, direction of water fluxes and currents. Rarely coastal areas and proximal rivers mouths are studied in a coupled way, but indeed they should be seen as a continuum and not as two uncorrelated realities separated by a rigid edge. Indeed observations suggest how extreme events as wave storm and river floods are often simultaneous because they are generated by the same large perturbations. In this work we explore the bivariate distribution of daily river discharge and daily average of sea waves with reference to estuarine areas. We will consider three points on the Sicilian (Italy) shoreline as case studies: one on the North, one in the East and the latter in the South-West coast. Each considered point is an outlet of a basin where measured or reconstructed streamflow series are available from 1979 to 2010. The considered basins differ also in area, ranging from 100 up to 4000 km2. In the same time slot, wave series have been obtained taking advantage of a reanalysis database elaborated on a hourly basis with a model implemented at DICCA (www.dicca.unige.it/meteocean) on the whole Mediterranean basin. Results show large part of relative frequencies in the range of low discharge and small waves and an exponential decrease for increasing wave height and river flow. Extreme floods never occur in calm sea conditions as sea storms are often accompanied by high levels of river discharges.

  4. Use of a Smartphone for Collecting Data on River Discharge and Communication of Flood Risk.

    NASA Astrophysics Data System (ADS)

    Pena-Haro, S.; Lüthi, B.; Philippe, T.

    2015-12-01

    Although many developed countries have well-established systems for river monitoring and flood early warning systems, the population affected in developing countries by flood events is unsettled. Even more, future climate development is likely to increase the intensity and frequency of extreme weather events and therefore bigger impacts on the population can be expected.There are different types of flood forecasting systems, some are based on hydrologic models fed with rainfall predictions and observed river levels. Flood hazard maps are also used to increase preparedness in case of an extreme event, however these maps are static since they do not incorporate daily changing conditions on river stages. However, and especially in developing countries, data on river stages are scarce. Some of the reasons are that traditional fixed monitoring systems do not scale in terms of costs, repair is difficult as well as operation and maintenance, in addition vandalism poses additional challenges. Therefore there is a need of cheaper and easy-to-use systems for collecting information on river stage and discharge. We have developed a mobile device application for determining the water stage and discharge of open-channels (e.g. rivers, artificial channels, irrigation furrows). Via image processing the water level and surface velocity are measured, combining this information with priori knowledge on the channel geometry the discharge is estimated. River stage and discharge measurement via smart phones provides a non-intrusive, accurate and cost-effective monitoring method. No permanent installations, which can be flooded away, are needed. The only requirement is that the field of view contains two reference markers with known scale and with known position relative to the channel geometry, therefore operation and maintenance costs are very low. The other advantage of using smartphones, is that the data collected can be immediately sent via SMS to a central database. This

  5. Gradients in coral reef communities exposed to muddy river discharge in Pohnpei, Micronesia

    NASA Astrophysics Data System (ADS)

    Golbuu, Yimnang; Fabricius, Katharina; Victor, Steven; Richmond, Robert H.

    2008-01-01

    This study analyzed how coral communities change along a gradient of increasing exposure to a mud-discharging river in the Enipein Catchment, Pohnpei, Micronesia. Using video transects, we quantified benthic communities at five sites along a gradient moving away from the river mouth towards the barrier reef. The most river-impacted site was characterized by a high accumulation of mud, low coral cover and low coral diversity. Although coral cover leveled off at ˜400 m from the river mouth to values found at the outer-most sites, coral diversity continued to increase with increasing distance, suggesting that the most distant site was still impacted by the river discharges. Fungiidae, Pavona, Acropora, Pachyseris and Porites rus all significantly increased in cover with distance from the river, while Turbinaria decreased. The combined presence and abundance of these six species groups, together with coral species richness, may help to indicate the effects of terrestrial runoff in similar runoff-exposed settings around Micronesia, whereas coral cover is not a sensitive indicator for river impact. Coral reefs are important resources for the people of Pohnpei. To prevent further degradation of this important resource, an integrated watershed approach is needed to control terrestrial activities.

  6. Heated Discharge Control and Management Alternatives: Small Water Bodies and Rivers.

    ERIC Educational Resources Information Center

    MacLaren, James F.

    Basic concepts of waste heat management on shallow and deep small water bodies and rivers are reviewed and examples are given. This study defines a small water body as a body in which the far field hydrothermal effects of a heated discharge can be detected in a major portion or practically all of the water body. Environmental effects due to…

  7. Continuous measurement of suspended-sediment discharge in rivers by use of optical backscatterance sensors

    USGS Publications Warehouse

    Schoellhamer, D.H.; Wright, S.A.; Bogen, J.; Fergus, T.; Walling, D.

    2003-01-01

    Optical sensors have been used to measure turbidity and suspended-sediment concentration by many marine and estuarine studies, and optical sensors can provide automated, continuous time series of suspended-sediment concentration and discharge in rivers. Three potential problems with using optical sensors are biological fouling, particle-size variability, and particle-reflectivity variability. Despite varying particle size, output from an optical backscatterance sensor in the Sacramento River at Freeport, California, USA, was calibrated successfully to discharge-weighted, cross-sectionally averaged suspended-sediment concentration, which was measured with the equal discharge-, or width-increment, methods and an isokinetic sampler. A correction for sensor drift was applied to the 3-year time series. However, the calibration of an optical backscatterance sensor used in the Colorado River at Cisco, Utah, USA, was affected by particle-size variability. The adjusted time series at Freeport was used to calculate hourly suspended-sediment discharge that compared well with daily values from a sediment station at Freeport. The appropriateness of using optical sensors in rivers should be evaluated on a site-specific basis and measurement objectives, potential particle size effects, and potential fouling should be considered.

  8. Modern pollen distribution in the Adriatic Sea reflecting river discharge provenance.

    NASA Astrophysics Data System (ADS)

    Ruiz Soto, Salvador; Zonneveld, Karin A. F.; Donders, Timme; Sangiorgi, Francesca

    2017-04-01

    It is well known that the pollen/spores observed in marine sediments can have an alluvial or fluviatile origin. However, to date detailed information about the transport and settlement processes in marine environments in the vicinity of river mouths is relatively limited. Here we present information about these transport and settling processes along the western Adriatic Sea margin. In this region numerous rivers drain into the Adriatic Sea, though the water discharge varies depending on the season. Due to the local ocean current system these discharge waters are pressed against the eastern Italian coast resulting in the presence of a band of southward flowing discharge waters that mix slowly with Mediterranean Sea waters on their way south. We provide information about the pollen/spore association in surface sediments from marine sediments and selected river. We compare the association of river sediments previous to entering the marine realm and to associations at locations in the marine extension of the discharge waters. We discuss transport, mixing and settling processes and provide information about to what extent the pollen/spore association reflect the vegetation in the catchment of the studied region.

  9. Emerging and Conventional Contaminants in River Waters Discharging into the Black Sea along the Ukrainian Coast

    EPA Science Inventory

    The major rivers of Ukraine, including the Dnieper, Dniester, Southern Bug and Danube, discharge approximately 8500 m3/s of freshwater into the northern and western portions of the Black Sea. As one of the largest countries in Europe, Ukraine also has one of the largest human po...

  10. Discharge of the nile river: a barometer of short-period climate variation.

    PubMed

    Riehl, H; Meitín, J

    1979-12-07

    Eight events of climate variation with durations of the order of 100 years have been found in the history of annual Nile River discharge dating from the year 622. They cease during the "little climatic optimum" in the North Atlantic and then reappear and intensify; this behavior suggests that control is from the belt of the polar westerlies.

  11. Submarine fresh groundwater discharge into Laizhou Bay comparable to the Yellow River flux

    PubMed Central

    Wang, Xuejing; Li, Hailong; Jiao, Jiu Jimmy; Barry, D. A.; Li, Ling; Luo, Xin; Wang, Chaoyue; Wan, Li; Wang, Xusheng; Jiang, Xiaowei; Ma, Qian; Qu, Wenjing

    2015-01-01

    Near- and off-shore fresh groundwater resources become increasingly important with the social and economic development in coastal areas. Although large scale (hundreds of km) submarine groundwater discharge (SGD) to the ocean has been shown to be of the same magnitude order as river discharge, submarine fresh groundwater discharge (SFGD) with magnitude comparable to large river discharge is never reported. Here, we proposed a method coupling mass-balance models of water, salt and radium isotopes based on field data of 223Ra, 226Ra and salinity to estimate the SFGD, SGD. By applying the method in Laizhou Bay (a water area of ~6000 km2), we showed that the SFGD and SGD are 0.57 ~ 0.88 times and 7.35 ~ 8.57 times the annual Yellow River flux in August 2012, respectively. The estimate of SFGD ranges from 4.12 × 107 m3/d to 6.36 × 107 m3/d, while SGD ranges from 5.32 × 108 m3/d to 6.20 × 108 m3/d. The proportion of the Yellow River input into Laizhou Bay was less than 14% of the total in August 2012. Our method can be used to estimate SFGD in various coastal waters. PMID:25742712

  12. Submarine fresh groundwater discharge into Laizhou Bay comparable to the Yellow River flux.

    PubMed

    Wang, Xuejing; Li, Hailong; Jiao, Jiu Jimmy; Barry, D A; Li, Ling; Luo, Xin; Wang, Chaoyue; Wan, Li; Wang, Xusheng; Jiang, Xiaowei; Ma, Qian; Qu, Wenjing

    2015-03-06

    Near- and off-shore fresh groundwater resources become increasingly important with the social and economic development in coastal areas. Although large scale (hundreds of km) submarine groundwater discharge (SGD) to the ocean has been shown to be of the same magnitude order as river discharge, submarine fresh groundwater discharge (SFGD) with magnitude comparable to large river discharge is never reported. Here, we proposed a method coupling mass-balance models of water, salt and radium isotopes based on field data of (223)Ra, (226)Ra and salinity to estimate the SFGD, SGD. By applying the method in Laizhou Bay (a water area of ~6000 km(2)), we showed that the SFGD and SGD are 0.57 ~ 0.88 times and 7.35 ~ 8.57 times the annual Yellow River flux in August 2012, respectively. The estimate of SFGD ranges from 4.12 × 10(7) m(3)/d to 6.36 × 10(7) m(3)/d, while SGD ranges from 5.32 × 10(8) m(3)/d to 6.20 × 10(8) m(3)/d. The proportion of the Yellow River input into Laizhou Bay was less than 14% of the total in August 2012. Our method can be used to estimate SFGD in various coastal waters.

  13. Emerging and Conventional Contaminants in River Waters Discharging into the Black Sea along the Ukrainian Coast

    EPA Science Inventory

    The major rivers of Ukraine, including the Dnieper, Dniester, Southern Bug and Danube, discharge approximately 8500 m3/s of freshwater into the northern and western portions of the Black Sea. As one of the largest countries in Europe, Ukraine also has one of the largest human po...

  14. Heated Discharge Control and Management Alternatives: Small Water Bodies and Rivers.

    ERIC Educational Resources Information Center

    MacLaren, James F.

    Basic concepts of waste heat management on shallow and deep small water bodies and rivers are reviewed and examples are given. This study defines a small water body as a body in which the far field hydrothermal effects of a heated discharge can be detected in a major portion or practically all of the water body. Environmental effects due to…

  15. Sediment-discharge characteristics of the Toutle River following the Mount St. Helens eruption

    USGS Publications Warehouse

    Culbertson, J.K.; Dinehart, R.L.

    1982-01-01

    Dinehart, R.L., Culbertson, J.K., 1982, Sediment-discharge characteristics of the Toutle River following the Mount St. Helens eruption, [abs.]: in Proceedings from the Conference on Mount St. Helens— Effects on water resources: State of Washington Water Research Center, p. 149.

  16. Organic geochemistry and petroleum potential of Pennsylvanian black shales, Powder River and Denver basins

    SciTech Connect

    Clayton, J.L.; Lubeck, C.M.; King, J.D.; Daws, T.A.

    1987-05-01

    Thin, Middle Pennsylvanian organic-rich black shales (cumulative thickness generally less than 7 m) underlie much of the northern Denver basin and the southeastern Powder River basin. In the Powder River basin, these shales are part of the middle member of the Minnelusa Formation. During Desmoinesian time, the present-day area of the southeastern Powder River basin and the Nebraska panhandle was a shallow, at times highly saline restricted sea. In contrast, the black shales were deposited in a marine environment with normal salinity in the present-day area of northeastern Colorado, which was probably continuous with the Mid-Continent Pennsylvanian sea. Total organic carbon content of all the black shales is high (up to 20 wt. %) except along the margins of the ancient seaway and along the boundary between the open sea and the restricted basin (TOC < 2 wt. %). Extractable organic matter in the black shales is predominantly of marine origin. Evidence for marine organic material includes a predominance of low-molecular-weight alkanes (< C20) and absence of long-chain alkanes (> C25), very low saturated/aromatic hydrocarbon ratios (avg. 0.5), and relatively low pristane/phytane ratios (0.7-1.3). Although the black shales were apparently deposited in uniformly low-oxygen marine conditions, the restricted basin and open marine environments can be differentiated by organic geochemical analysis. Chloroform extracts from black shales from the restricted basin environment contain abundant red pigments, most likely derived from bacteria or algae requiring high salinity for growth. In contrast, extracts from the open marine shales, although equally organic rich, are devoid of pigments, suggesting depositional under conditions of normal seawater salinity. In bulk, organic matter in black shales from both environments is type II and has good potential for generation of liquid hydrocarbons during catagenesis.

  17. Hydrogeologic controls on ground-water and contaminant discharge to the Columbia River near the Hanford Townsite

    SciTech Connect

    Luttrell, S.P.; Newcomer, D.R.; Teel, S.S.; Vermeul, V.R.

    1992-11-01

    The purpose of this study is to quantify ground-water and contaminant discharge to the Columbia River in the Hanford Townsite vicinity. The primary objectives of the work are to: describe the hydrogeologic setting and controls on ground-water movement and contaminant discharge to the Columbia River; understand the river/aquifer relationship and its effects on contaminant discharge to the Columbia River; quantify the ground-water and contaminant mass discharge to the Columbia River; and provide data that may be useful for a three-dimensional model of ground-water flow and contaminant transport in the Hanford Townsite study area. The majority of ground-water contamination occurs within the unconfined aquifer; therefore, ground-water and contaminant discharge from the unconfined aquifer is the emphasis of this study. The period of study is primarily from June 1990 through March 1992.

  18. Hydrogeologic controls on ground-water and contaminant discharge to the Columbia River near the Hanford Townsite

    SciTech Connect

    Luttrell, S.P.; Newcomer, D.R.; Teel, S.S.; Vermeul, V.R.

    1992-11-01

    The purpose of this study is to quantify ground-water and contaminant discharge to the Columbia River in the Hanford Townsite vicinity. The primary objectives of the work are to: describe the hydrogeologic setting and controls on ground-water movement and contaminant discharge to the Columbia River; understand the river/aquifer relationship and its effects on contaminant discharge to the Columbia River; quantify the ground-water and contaminant mass discharge to the Columbia River; and provide data that may be useful for a three-dimensional model of ground-water flow and contaminant transport in the Hanford Townsite study area. The majority of ground-water contamination occurs within the unconfined aquifer; therefore, ground-water and contaminant discharge from the unconfined aquifer is the emphasis of this study. The period of study is primarily from June 1990 through March 1992.

  19. Trend Analysis of Golestan's Rivers Discharges Using Parametric and Non-parametric Methods

    NASA Astrophysics Data System (ADS)

    Mosaedi, Abolfazl; Kouhestani, Nasrin

    2010-05-01

    One of the major problems in human life is climate changes and its problems. Climate changes will cause changes in rivers discharges. The aim of this research is to investigate the trend analysis of seasonal and yearly rivers discharges of Golestan province (Iran). In this research four trend analysis method including, conjunction point, linear regression, Wald-Wolfowitz and Mann-Kendall, for analyzing of river discharges in seasonal and annual periods in significant level of 95% and 99% were applied. First, daily discharge data of 12 hydrometrics stations with a length of 42 years (1965-2007) were selected, after some common statistical tests such as, homogeneity test (by applying G-B and M-W tests), the four mentioned trends analysis tests were applied. Results show that in all stations, for summer data time series, there are decreasing trends with a significant level of 99% according to Mann-Kendall (M-K) test. For autumn time series data, all four methods have similar results. For other periods, the results of these four tests were more or less similar together. While, for some stations the results of tests were different. Keywords: Trend Analysis, Discharge, Non-parametric methods, Wald-Wolfowitz, The Mann-Kendall test, Golestan Province.

  20. River discharge controls phytoplankton dynamics in the northern San Francisco Bay estuary

    USGS Publications Warehouse

    Cloern, J.E.; Alpine, A.E.; Cole, B.E.; Wong, R.L.J.; Arthur, J.F.; Ball, M.D.

    1983-01-01

    Phytoplankton dynamics in the upper reach of the northern San Francisco Bay estuary are usually characterized by low biomass dominated by microflagellates or freshwater diatoms in winter, and high biomass dominated by neritic diatoms in summer. During two successive years of very low river discharge (the drought of 1976-77), the summer diatom bloom was absent. This is consistent with the hypothesis that formation of the diatom population maximum is a consequence of the same physical mechanisms that create local maxima of suspended sediments in partially-mixed estuaries: density-selective retention of particles within an estuarine circulation cell. Because the estuary is turbid, calculated phytoplankton growth rates are small in the central deep channel but are relatively large in lateral shallow embayments where light limination is less severe. When river discharge falls within a critical range (100-350 m3 s-1) that positions the suspended particulate maximum adjacent to the productive shallow bays, the population of neritic diatoms increases. However, during periods of high discharge (winter) or during periods of very low discharge (drought), the suspended particulate maximum is less well-defined and is uncoupled (positioned downstream or upstream) from the shallow bays of the upper estuary, and the population of neritic diatoms declines. Hence, the biomass and community composition of phytoplankton in this estuary are controlled by river discharge. ?? 1983.

  1. Salt Plug Formation Caused by Decreased River Discharge in a Multi-channel Estuary

    PubMed Central

    Shaha, Dinesh Chandra; Cho, Yang-Ki

    2016-01-01

    Freshwater input to estuaries may be greatly altered by the river barrages required to meet human needs for drinking water and irrigation and prevent salt water intrusion. Prior studies have examined the salt plugs associated with evaporation and salt outwelling from tidal salt flats in single-channel estuaries. In this work, we discovered a new type of salt plug formation in the multi-channel Pasur River Estuary (PRE) caused by decreasing river discharges resulting from an upstream barrage. The formation of a salt plug in response to changes in river discharge was investigated using a conductivity-temperature-depth (CTD) recorder during spring and neap tides in the dry and wet seasons in 2014. An exportation of saline water from the Shibsa River Estuary (SRE) to the PRE through the Chunkhuri Channel occurred during the dry season, and a salt plug was created and persisted from December to June near Chalna in the PRE. A discharge-induced, relatively high water level in the PRE during the wet season exerted hydrostatic pressure towards the SRE from the PRE and thereby prevented the intrusion of salt water from the SRE to the PRE. PMID:27255892

  2. Salt Plug Formation Caused by Decreased River Discharge in a Multi-channel Estuary

    NASA Astrophysics Data System (ADS)

    Shaha, Dinesh Chandra; Cho, Yang-Ki

    2016-06-01

    Freshwater input to estuaries may be greatly altered by the river barrages required to meet human needs for drinking water and irrigation and prevent salt water intrusion. Prior studies have examined the salt plugs associated with evaporation and salt outwelling from tidal salt flats in single-channel estuaries. In this work, we discovered a new type of salt plug formation in the multi-channel Pasur River Estuary (PRE) caused by decreasing river discharges resulting from an upstream barrage. The formation of a salt plug in response to changes in river discharge was investigated using a conductivity-temperature-depth (CTD) recorder during spring and neap tides in the dry and wet seasons in 2014. An exportation of saline water from the Shibsa River Estuary (SRE) to the PRE through the Chunkhuri Channel occurred during the dry season, and a salt plug was created and persisted from December to June near Chalna in the PRE. A discharge-induced, relatively high water level in the PRE during the wet season exerted hydrostatic pressure towards the SRE from the PRE and thereby prevented the intrusion of salt water from the SRE to the PRE.

  3. Application for 3d Scene Understanding in Detecting Discharge of Domesticwaste Along Complex Urban Rivers

    NASA Astrophysics Data System (ADS)

    Ninsalam, Y.; Qin, R.; Rekittke, J.

    2016-06-01

    In our study we use 3D scene understanding to detect the discharge of domestic solid waste along an urban river. Solid waste found along the Ciliwung River in the neighbourhoods of Bukit Duri and Kampung Melayu may be attributed to households. This is in part due to inadequate municipal waste infrastructure and services which has caused those living along the river to rely upon it for waste disposal. However, there has been little research to understand the prevalence of household waste along the river. Our aim is to develop a methodology that deploys a low cost sensor to identify point source discharge of solid waste using image classification methods. To demonstrate this we describe the following five-step method: 1) a strip of GoPro images are captured photogrammetrically and processed for dense point cloud generation; 2) depth for each image is generated through a backward projection of the point clouds; 3) a supervised image classification method based on Random Forest classifier is applied on the view dependent red, green, blue and depth (RGB-D) data; 4) point discharge locations of solid waste can then be mapped by projecting the classified images to the 3D point clouds; 5) then the landscape elements are classified into five types, such as vegetation, human settlement, soil, water and solid waste. While this work is still ongoing, the initial results have demonstrated that it is possible to perform quantitative studies that may help reveal and estimate the amount of waste present along the river bank.

  4. Geologic applications of thermal-inertia mapping from satellite. [Powder River Basin, Wyoming

    NASA Technical Reports Server (NTRS)

    Offield, T. W. (Principal Investigator); Miller, S. H.; Watson, K.

    1979-01-01

    The author has identified the following significant results. After digitization, a noise rejection filter was applied to data obtained by USGS aircraft. An albedo image was formed by combining three bands of visible data. Along with the day and nighttime thermal data, the albedo image was used to construct a relative thermal-inertia image. This image, registered to a topographic base, shows there are thermal property differences in the vicinity of the contact between the Fort Union and Wasatch formations in the Powder River Basin, Wyoming.

  5. Stratigraphic framework of the upper Fort Union Formation, TA Hills, Western Powder River basin, Wyoming

    USGS Publications Warehouse

    Weaver, Jean N.; Flores, Romeo M.

    1985-01-01

    The purpose of this study is to interpret a relationship between the stratigraphy and the environment of deposition of the upper part of the Fort Union Formation in the TA Hills in the western part of the Powder River Basin, Johnson County, Wyoming.  This framework was used to map and correlate coal beds with those mapped by Hose (1955) and Mapel (1959) in the southern and northern parts of the study area, respectively.  More specifically, the established stratigraphic and environmental relationships of the coal beds and associated rocks contribute to a depositional model for the upper part of the Fort Union Formation in the TA Hills.

  6. Estimated resources on non-leased federal coal, Powder River basin, Montana and Wyoming

    USGS Publications Warehouse

    Trent, V.A.

    1986-01-01

    From V. A. Trent, 1986, USGS Map MF-1887     Maps are generated by combining digital ownership data with geologic resource estimates and other spatial coal data in a geographic information system (GIS). For example, we merged the newly compiled Federal coal ownership files with resource calculations from the 1970's for the Powder River Basin (Trent, 1986). For the first time, we are able to visually display the location of Federally owned coal in each 7.5' quadrangle along with the published coal resource estimates for those areas (fig. 8).

  7. Geology and water-yielding characteristics of rocks of the northern Powder River basin, southeastern Montana

    USGS Publications Warehouse

    Lewis, Barney D.; Roberts, Robert S.

    1978-01-01

    Numerous and widespread subbituminous and lignite coal deposits occur in the Powder River Basin in southeastern Montana, principally within the Fort Union Formation. Many of the coal beds are less than 250 feet (76.2 m) below land surface and are, therefore, mineable by surface methods. Individual cola beds are commonly 20-30 feet (6.1-9.1 m) thick, but may be as much as 80 feet (24 m). These factors, coupled with the low-sulfur content of the coal, make it attractive as a major energy resource. 

  8. Geologic application of thermal-inertia mapping from satellite. [Powder River Basin, Wyoming

    NASA Technical Reports Server (NTRS)

    Offield, T. W. (Principal Investigator); Miller, S. H.; Watson, K.

    1980-01-01

    The author has identified the following significant results. Two night-time thermal images of the Powder River Basin, Wyoming distinctly show a major thermal feature. This feature is substantially coincident with a drainage divide and the southward facing slope appears cooler, suggesting a lower thermal inertia. An initial examination of regional geologic maps provides no clear evidence to suggest what type of geologic feature or structure may be present, although it can be noted that its northeastern end passes directly through Lead, South Dakota where the Homestake Gold Mine is located.

  9. Observed shift towards earlier spring discharge in the main Alpine rivers.

    PubMed

    Zampieri, Matteo; Scoccimarro, Enrico; Gualdi, Silvio; Navarra, Antonio

    2015-01-15

    In this study, we analyse the observed long-term discharge time-series of the Rhine, the Danube, the Rhone and the Po rivers. These rivers are characterised by different seasonal cycles reflecting the diverse climates and morphologies of the Alpine basins. However, despite the intensive and varied water management adopted in the four basins, we found common features in the trend and low-frequency variability of the spring discharge timings. All the discharge time-series display a tendency towards earlier spring peaks of more than two weeks per century. These results can be explained in terms of snowmelt, total precipitation (i.e. the sum of snowfall and rainfall) and rainfall variability. The relative importance of these factors might be different in each basin. However, we show that the change of seasonality of total precipitation plays a major role in the earlier spring runoff over most of the Alps.

  10. Image analysis techniques to estimate river discharge using time-lapse cameras in remote locations

    NASA Astrophysics Data System (ADS)

    Young, David S.; Hart, Jane K.; Martinez, Kirk

    2015-03-01

    Cameras have the potential to provide new data streams for environmental science. Improvements in image quality, power consumption and image processing algorithms mean that it is now possible to test camera-based sensing in real-world scenarios. This paper presents an 8-month trial of a camera to monitor discharge in a glacial river, in a situation where this would be difficult to achieve using methods requiring sensors in or close to the river, or human intervention during the measurement period. The results indicate diurnal changes in discharge throughout the year, the importance of subglacial winter water storage, and rapid switching from a "distributed" winter system to a "channelised" summer drainage system in May. They show that discharge changes can be measured with an accuracy that is useful for understanding the relationship between glacier dynamics and flow rates.

  11. Description of data reanalysis of daily discharge and gauge height over the Amazon River Basin

    NASA Astrophysics Data System (ADS)

    Sviercoski, R. F.; Travis, B. J.; Eggert, K.

    2016-10-01

    The Amazon River is the world's largest, discharging more water to the ocean than any other river. Study of the world's freshwater resources becomes more significant with increasing awareness of global climate change and its potential effect on those resources and atmospheric forcing. In this work, a reanalysis of the daily discharge and gauge height data for 87 active gauge stations throughout the Amazon River Basin is presented. The data was originally obtained from the web site maintained by ANEEL - Brazilian Electricity Regulatory Agency. We describe the problems encountered in trying to use the original data and the assumptions applied in the reanalysis procedure. The reanalysis consisted of filtering inconsistencies in the comma (decimal) notation, filling in missing data, and replacing inconsistent data values by applying the assumption of a stationary Markov process. The reanalyzed data is available to the community through an anonymous ftp-site.

  12. The Quality of Water Discharging From the New River and Clear Fork Basins, Tennessee

    USGS Publications Warehouse

    Parker, R.S.; Carey, W.P.

    1980-01-01

    The quality of water discharging from a strip-mined basin and a relatively unmined basin on the Cumberland Plateau in Tennessee are examined and compared. The chemical and aesthetic quality of these waters will directly affect the chemical and aesthetic quality of the water flowing through a proposed national river and recreation area. Water from the heavily mined New River basin is characterized by neutral pH, low dissolved solids (less than 300 milligrams per liter), and high concentrations of suspended sediment. More than 90 percent of the suspended sediment is silt and clay. Suspended-sediment concentrations in the thousands of milligrams per liter are not uncommon for New River and often impart a highly turbid appearance to the water. Approximately 590,000 tons of suspended sediment were discharged from the New River basin in 1977, as compared to an estimated 20,000 tons from the relatively unmined Clear Fork basin. In association with these fine-grain suspended sediments are sorbed trace metals. In 1977 the New River basin discharged an estimated 17,000 tons of suspended iron while Clear Fork discharged an estimated 600 tons. Suspended-sediment concentration was found to be highly correlated with both suspended and total trace-metal concentrations. This correlation coupled with the nearly neutral pH of the water indicates that trace metals are transported primarily in the suspended phase. The most promising indicator of the presence of coal mining was found to be dissolved sulfate. All unmined basins sampled in this study showed dissolved sulfate concentrations less than 20 milligrams per liter, whereas all mined basins had dissolved-sulfate concentrations in excess of 20 milligrams per liter regardless of basin size or discharge.

  13. Discharge, water quality, and native fish abundance in the Virgin River, Utah, Nevada, and Arizona, in support of Pah Tempe Springs discharge remediation efforts

    USGS Publications Warehouse

    Miller, Matthew P.; Lambert, Patrick M.; Hardy, Thomas B.

    2014-01-01

    Pah Tempe Springs discharge hot, saline, low dissolved-oxygen water to the Virgin River in southwestern Utah, which is transported downstream to Lake Mead and the Colorado River. The dissolved salts in the Virgin River negatively influence the suitability of this water for downstream agricultural, municipal, and industrial use. Therefore, various remediation scenarios to remove the salt load discharged from Pah Tempe Springs to the Virgin River are being considered. One concern about this load removal is the potential to impact the ecology of the Virgin River. Specifically, information is needed regarding possible impacts of Pah Tempe Springs remediation scenarios on the abundance, distribution, and survival of native fish in the Virgin River. Future efforts that aim to quantitatively assess how various remediation scenarios to reduce the load of dissolved salts from Pah Tempe Springs into the Virgin River may influence the abundance, distribution, and survival of native fish will require data on discharge, water quality, and native fish abundance. This report contains organized accessible discharge, water quality, and native fish abundance data sets from the Virgin River, documents the compilation of these data, and discusses approaches for quantifying relations between abiotic physical and chemical conditions, and fish abundance.

  14. Diagnostics and Prediction of Anomalous River Discharge in Northern South America.

    NASA Astrophysics Data System (ADS)

    Hastenrath, Stefan

    1990-10-01

    The annual cycles of rainfall and river discharge in northern South America are dominated by the seasonal latitude migration of the intertropical convergence zone. The catchments in the west (Madden. Magdalena and Orinoco) have their high stands between August and December, while those of the Guyanas (Cuyuni, Essequibo, Suriname, Maroni and Oyapock) peak between May and July. Anomalously abundant discharge is in almost all catchments (except Orinoco) associated with the high SO phase (defined by anomalously high/low pressure at Tahiti/Darwin), weakened Caribbean tradewinds. and accelerated cross-equatorial southerly flow over the eastern Pacific.In a series of experiments a sharp distinction was kept between a `dependent' dataset (1940-70, or the part available in the river series) used as training period and an `independent' portion of the record (1971-87) reserved for prediction. Stepwise multiple regression models for bimonthly `seasons' used as input river discharge as regressand, and as regressors index series of Tahiti minus Darwin pressure difference, equatorial Pacific sea surface temperature PWT, zonal wind component over the Caribbean and meridional wind component over the eastern equatorial Pacific, all two seasons earlier. The resulting equations were then used to predict the discharge anomalies in the independent dataset 1971-87. There is considerable predictive skill for various rivers/seasons, with the overall best predictability for the low discharge time of year. In particular, for Magdalena 55% and for Essequibo 74% of the interannual variance of January-February discharge during 1971-87 is predictable by this method, in which for Essequibo PWT serves as sole predictor.

  15. Assessing modern rates of river sediment discharge to the ocean using satellite gravimetry

    NASA Astrophysics Data System (ADS)

    Mouyen, Maxime; Longuevergne, Laurent; Steer, Philippe; Crave, Alain; Lemoine, Jean-Michel; Save, Himanshu; Robin, Cécile

    2017-04-01

    Worldwide rivers annually export about 19 Gigatons of sediments to the ocean that mostly accumulate in the coastal zones and on the continental shelves. This sediment discharge testifies of the intensity of continental erosion and records changes in climate, tectonics and human activity. However, natural and instrumental uncertainties inherent to the in-situ measurements of sediment discharge prevent from conclusive estimates to better understand these linkages. Here we develop a new method, using the Gravity Recovery and Climate Experiment (GRACE) satellite data, to infer mass-integrative estimates of sediment discharge of large rivers to the ocean. GRACE satellite provides global gravity time series that have proven useful for quantifying mass transport, including continental water redistribution at the Earth surface (ice sheets and glaciers melting, groundwater storage variations) but has been seldom used for monitoring sediment mass transfers so far. Here we pair the analysis of regularized GRACE solutions at high spatial resolution corrected from all known contributions (hydrology, ocean, atmosphere) to a particle tracking model that predicts the location of the sediment sinks for 13 rivers with the highest sediments loads in the world. We find that the resulting GRACE-derived sediment discharges off the mouth of the Amazon, Ganges-Brahmaputra, Changjiang (Yangtze), Indus, Magdalena, Godavari and Mekong rivers are consistent with in-situ measurements. Our results suggest that the lack of time continuity and of global coverage in terrestrial sediment discharge measurements could be reduced by using GRACE, which provides global and continuous data since 2002. GRACE solutions are regularly improved and new satellite gravity missions are being prepared hence making our approach even more relevant in a near future. The accumulation of sediments over time will keep increasing the signal to noise ratio of the gravity time series, which will improve the precision of

  16. River discharge and flood inundation over the Amazon based on IPCC AR5 scenarios

    NASA Astrophysics Data System (ADS)

    Paiva, Rodrigo; Sorribas, Mino; Jones, Charles; Carvalho, Leila; Melack, John; Bravo, Juan Martin; Beighley, Edward

    2015-04-01

    Climate change and related effects over the hydrologic regime of the Amazon River basin could have major impacts over human and ecological communities, including issues with transportation, flood vulnerability, fisheries and hydropower generation. We examined future changes in discharge and floodplain inundation within the Amazon River basin. We used the hydrological model MGB-IPH (Modelo de Grandes Bacias - Instituto de Pesquisas Hidráulicas) coupled with a 1D river hydrodynamic model simulating water storage over the floodplains. The model was forced using satellite based precipitation from the TRMM 3B42 dataset, and it had a good performance when validated against discharge and stage measurements as well as remotely sensed data, including radar altimetry-based water levels, gravity anomaly-based terrestrial water storage and flood inundation extent. Future scenarios of precipitation and other relevant climatic variables for the 2070 to 2100 time period were taken from five coupled atmosphere-ocean general circulation models (AOGCMs) from IPCC's Fifth Assessment Report (AR5) Coupled Model Intercomparison Project Phase 5 (CMIP5). The climate models were chosen based on their ability to represent the main aspects of recent (1970 to 2000) Amazon climate. A quantile-quantile bias removal procedure was applied to climate model precipitation to mitigate unreliable predictions. The hydrologic model was then forced using past observed climate data altered by delta change factors based on the past and future climate models aiming to estimate projected discharge and floodplain inundation in climate change scenario at several control points in the basin. The climate projections present large uncertainty, especially the precipitation rate, and predictions using different climate models do not agree on the sign of changes on total Amazon flood extent or discharge along the main stem of the Amazon River. However, analyses of results at different regions indicate an increase

  17. Evolution of the hydromorphodynamics of mountain river confluences for varying discharge ratios and junction angles

    NASA Astrophysics Data System (ADS)

    Guillén-Ludeña, S.; Franca, M. J.; Cardoso, A. H.; Schleiss, A. J.

    2016-02-01

    Mountain river confluences are characterized by narrow and steep tributaries that supply abundant sediment load to a main channel that, in turn, provides the dominant flow discharge. In addition, bed sediments consist of poorly sorted mixtures that promote bed armoring. The knowledge of the hydrodynamics and morphodynamics of mountain river confluences is sparse because most of the existent studies on confluence dynamics focus on lowland confluences. This study aims at examining the influence of the junction angle (α) and discharge ratio (Qr = Qt / Qm) on flow dynamics and bed morphology of mountain river confluences. This study presents the results of six laboratory experiments in which three discharge ratios were tested (Qr = Qt / Qm = 0.11, 0.15, 0.23) with two different junction angles (α = 90° and 70°). The experiments were conducted under movable bed conditions and with continuous sediment supply to both flumes. Measurements consisted of systematic bed topography and water surface surveys performed at different instants during the experiments and at equilibrium, i.e., when the outgoing sediment rate coincided with the incoming and bed topography reached a steady state. The results show that the discharge ratio and the junction angle parameters are major controls of the dynamics of mountain river confluences. Also, the evolution of bed morphology and flow dynamics for varying junction angles and discharge ratios present some patterns that contrast with those reported for lowland confluences. Among these patterns are the different flow regimes adopted by the tributary for different junction angles and the decrease of the height of the bank-attached bar for increasing discharge ratios. Moreover, results show that the abundant sediment load of the tributary plays a major role on the dynamics of this type of confluence. This load resulted in a marked bed discordance that, in turn, influenced flow dynamics and bed morphology of the confluence.

  18. Does Water Management Reduce uncertainty of Projected Climate Change Impacts on River Discharge?

    NASA Astrophysics Data System (ADS)

    Pohle, I.; Koch, H.; Gaedeke, A.; Hinz, C.; Grünewald, U.

    2015-12-01

    Climate change impact studies are associated with error propagation and amplification of uncertainties through model chains. Water management, especially reservoir management, reduces discharge variability. In this study we investigated how water management influences uncertainty propagation of climate change scenarios. We applied a model ensemble of (i) the regional climate model STAR (STAR 0K: no further climate change, STAR 2K and 3K: increase of mean annual temperature by 2 K and 3 K resp.; each scenario is represented by 100 realizations), (ii) the hydrological models SWIM and EGMO, and (iii) the water management model WBalMo. The study was performed in the two neighbouring catchments of the Schwarze Elster River (Germany) and the Spree River (Germany and Czech Republic). These catchments have similar climate, topography and land use, but differ in their water management. The Spree River has a higher reservoir capacity, more withdrawals and discharges from water users and more water transfers. The projected natural runoff in both catchments is similar. Compared to STAR 0K, the natural runoff decreases remarkably in the other climate scenarios. The uncertainties related to the climate projection are propagated through the hydrological model. In the Schwarze Elster River catchment, these uncertainties are slightly increased by the water management model, whereas in the Spree River catchment, due to a higher reservoir capacity and more water transfers, interannual variability and uncertainty of managed discharge are strongly moderated by water management. The results of this study imply that generally, effective water management can reduce uncertainty related to climate change impacts on river discharge. Catchments with a high storage ratio are less vulnerable to changing climate conditions. This underlines the role of water management in coping with climate change impacts. Yet, due to decreasing reservoir volumes in drought periods, reservoir management alone

  19. Determination of trace elements in high purity alumina powder by helium enhanced direct current glow discharge mass spectrometry

    NASA Astrophysics Data System (ADS)

    Jung, Sehoon; Kim, Sunhye; Hinrichs, Joachim

    2016-08-01

    Trace impurities in high purity alumina powder were determined by fast flow direct current glow discharge mass spectrometry (GD-MS). The non-conductive samples were prepared with high purity graphite powder and used as a sample binder and as a secondary cathode. To improve the sensitivity of the GD-MS analysis, helium was introduced as an additional glow discharge gas to argon plasma. The quantification results of the GD-MS measurement were calculated by external calibration with matrix matched certified reference materials. The GD-MS results for the determination of Na, Mg, Si, Ca, Ti, V, Cr, Fe, Cu, Zn and Ga in the alumina samples agreed well with the certified values of a reference material and the results of chemical analysis using wet sample digestion with inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). The GD-MS analysis is a rapid analysis technique to determine trace elements in non-conductive alumina to below mg·kg- 1 levels.

  20. State-discharge relations at dams on the Illinois and Des Plaines rivers in Illinois

    USGS Publications Warehouse

    Mades, Dean M.

    1981-01-01

    Stage-discharge relations were developed for the Brandon Road Dam on the Des Plainse River and the Dresden Island, Marseilles, Starved Rock, Peoria, and La Grange Dams on the Illinois River. At Brandon Road Dam, streamflow is regulated by the operation of tainter gates and headgates. Tainter gates are operated to regulate streamflow at the Dresden Island, Marseilles, and Starved Rock Dams. Peoria Dam and La Grange Dam comprise timber Chanoine wickets which are lowered to a horizontal position on the streambed when used for streamflow regulation. Both dams have concrete abutments housing butterfly valves that are also used for regulation. A total of 50 discharge measurements ranging from 49.0 to 2,450 cubic meter per second were used to determine discharge coefficients in equations expressing discharge as a function of headwater depth, tailwater depth, and gate opening. A stage-discharge relation for Chanoine wicket dams developed from a U.S. Army Corps of Engineers hydraulic model study in 1937 and 1938 was verified with discharge measurements made downstream from the Peoria and La Grange Dams. (USGS)

  1. Geospatial database of estimates of groundwater discharge to streams in the Upper Colorado River Basin

    USGS Publications Warehouse

    Garcia, Adriana; Masbruch, Melissa D.; Susong, David D.

    2014-01-01

    The U.S. Geological Survey, as part of the Department of the Interior’s WaterSMART (Sustain and Manage America’s Resources for Tomorrow) initiative, compiled published estimates of groundwater discharge to streams in the Upper Colorado River Basin as a geospatial database. For the purpose of this report, groundwater discharge to streams is the baseflow portion of streamflow that includes contributions of groundwater from various flow paths. Reported estimates of groundwater discharge were assigned as attributes to stream reaches derived from the high-resolution National Hydrography Dataset. A total of 235 estimates of groundwater discharge to streams were compiled and included in the dataset. Feature class attributes of the geospatial database include groundwater discharge (acre-feet per year), method of estimation, citation abbreviation, defined reach, and 8-digit hydrologic unit code(s). Baseflow index (BFI) estimates of groundwater discharge were calculated using an existing streamflow characteristics dataset and were included as an attribute in the geospatial database. A comparison of the BFI estimates to the compiled estimates of groundwater discharge found that the BFI estimates were greater than the reported groundwater discharge estimates.

  2. Copper speciation in continental inputs to the Vigo Ria: sewage discharges versus river fluxes.

    PubMed

    Santos-Echeandia, Juan; Laglera, Luis M; Prego, Ricardo; van den Berg, Constant M G

    2008-02-01

    Continental inputs of copper via rivers and sewage into the Vigo Ria were evaluated. The main fluvial input is not contaminated and the most degraded discharges occur on the southern margin of the middle ria. Continental inputs of copper and ligands to the ria are dominated by sewage treatment plants (136 mol Cu day(-1), 124 mol L day(-1)) supported by rivers (15 mol Cu day(-1), 21 mol L day(-1)). The dissolved fraction is the main channel of discharge for rivers (66%) with particulate matter being predominant in sewage (63%). Dissolved copper is organically complexed both in rivers (99.8%) and sewage (99.9%). This minor difference may be attributed to the fact that the stability of sewage complexes is greater than those in rivers. Moreover, ligand concentrations are higher in sewage than in rivers. Thus, the natural continental inputs of copper and ligands into the ria are magnified by anthropogenic inputs (5-15 and 3-5 times higher for copper and ligands, respectively).

  3. An improved methodology to estimate river stage and discharge using Jason-2 satellite data

    NASA Astrophysics Data System (ADS)

    Dubey, A. K.; Gupta, P. K.; Dutta, S.; Singh, R. P.

    2015-10-01

    Satellite altimetry over inland water bodies is a technique to estimate water level of rivers, lakes and reservoirs. In this study river flow characteristics such as water level and discharge is estimated using Jason-2, 20 Hz waveform data. An improved approach is adopted to retrieve the water level information over the braided reaches of the Brahmaputra river. The morphological dynamics of braided rivers often makes it difficult to retrieve water level accurately. In the proposed methodology, supplementary information from microwave and optical images of monsoon and non-monsoon seasons is used to establish the virtual stations over the main channel of the river. A nested approach is adopted to create dynamic virtual stations to address the frequent channel shifting phenomena over the braided reaches of the river. The results indicate that, there is high variation in backscattering coefficient, which ranges from mean value of 35 dB during the non-monsoon season to 48 dB during the monsoon season. It clearly highlights the seasonal variability of river flow in the Brahmaputra. The water level retrieval is done using Ice-1 retracking algorithm. The statistical analysis of retrieved water level have shown good agreement with in situ (observed) water levels when compared for Jason-2 satellite tracks 53, 166, 231 and 242 passing over the Brahmaputra river. The water level information is converted into discharge time series for the satellite 166 using the rating curve of Guwahati gauge station. The root mean square error of retrieved water levels is in the range of 50-55 cm. Water level retrieved using proposed methodology are compared with Hydroweb and DAHITI water level product. It was found that proposed methodology has enhanced the altimeter derived water level accuracy for the different reaches of the braided Brahmaputra river.

  4. Understanding the relationship between rainfall and river discharge: trends in an Amazonian watershed

    NASA Astrophysics Data System (ADS)

    Nóbrega, Rodolfo; Guzha, Alphonce; Freire, Paula; Santos, Celso; Gerold, Gerhard

    2013-04-01

    A research challenge in the Amazon rainforest is to understand different environmental patterns in a five million km2 region which with poor and/or unavailable environmental data. Deforestation and degradation in this forest have motivated intense monitoring activities in order to understand its impact and support the formulation of sustainable environmental policies. Time series analysis of hydrologic data is often use as a tool to evaluate watershed responses to climatic and anthropogenic influences. In this study, trend analysis of stream discharge from a 35600 km² watershed (Curuá River), located in southern Amazon was performed using 31 years discharge and rainfall data (1976-2006). The Curuá River is a tributary of Xingu River, site of the controversial Belo Monte dam. The aim of this work was to investigate the temporal variability of discharge, in relation to associated rainfall variability in order to contribute to a better understanding of the hydrological status of the watershed. The Mann Kendall non parametric tests were performed on daily, seasonal and annual discharge data. Frequency analysis using wavelet transform was also done, and annual and seasonal rainfall data was analyzed and correlated to discharge. Results from this study indicate decreasing trends in discharge (intra- and inter-annual) but while there is no evidence of a decreasing trend in in rainfall. Further interpretation of the data for possible causes of discharge changes is needed at the local study level, and implications of these results discussed in the context of climate change, deforestation and water resource management (including dam's constructions last decades). Results from this study do not confirm findings from other regional scale trend analyses, and therefore is it important to quantify the spatial extension of these decreasing stream flow trends in the Amazonia.

  5. Re-Evaluation of the 1921 Peak Discharge at Skagit River near Concrete, Washington

    USGS Publications Warehouse

    Mastin, M.C.

    2007-01-01

    The peak discharge record at the U.S. Geological Survey (USGS) gaging station at Skagit River near Concrete, Washington, is a key record that has come under intense scrutiny by the scientific and lay person communities in the last 4 years. A peak discharge of 240,000 cubic feet per second for the flood on December 13, 1921, was determined in 1923 by USGS hydrologist James Stewart by means of a slope-area measurement. USGS then determined the peak discharges of three other large floods on the Skagit River (1897, 1909, and 1917) by extending the stage-discharge rating through the 1921 flood measurement. The 1921 estimate of peak discharge was recalculated by Flynn and Benson of the USGS after a channel roughness verification was completed based on the 1949 flood on the Skagit River. The 1949 recalculation indicated that the peak discharge probably was 6.2 percent lower than Stewart's original estimate but the USGS did not officially change the peak discharge from Stewart's estimate because it was not more than a 10-percent change (which is the USGS guideline for revising peak flows) and the estimate already had error bands of 15 percent. All these flood peaks are now being used by the U.S. Army Corps of Engineers to determine the 100-year flood discharge for the Skagit River Flood Study so any method to confirm or improve the 1921 peak discharge estimate is warranted. During the last 4 years, two floods have occurred on the Skagit River (2003, 2006) that has enabled the USGS to collect additional data, do further analysis, and yet again re-evaluate the 1921 peak discharge estimate. Since 1949, an island/bar in the study reach has reforested itself. This has complicated the flow hydraulics and made the most recent recalculation of the 1921 flood based on channel roughness verification that used 2003 and 2006 flood data less reliable. However, this recent recalculation did indicate that the original peak-discharge calculation by Stewart may be high, and it added to a

  6. Comparing Postprocessing Approaches to Calibrating Operational River Discharge Forecasts

    NASA Astrophysics Data System (ADS)

    Hopson, T. M.; Webster, P. J.; Wood, A. W.

    2010-12-01

    With rare exceptions, current operational ensemble weather and hydrologic forecast systems require a final post-processing step to steer the forecast products towards satisfying the twin constraints of greater reliability while retaining (or enhancing) forecast sharpness. Such post-processing of model output can be viewed as an extension of the modeling effort itself, such as in the case of under-dispersive ensemble forecasts, where post-processing of the ensemble dispersion can implicitly account for missing scales of variability or mis-representation of physical processes. Over the last decade a number of different approaches have emerged that show consistent utility in calibrating ensembles derived from a variety of forecasting systems. In this work we compare and contrast four such approaches under differing operational constraints (e.g. data size limitations): logistic regression, an analogue approach, Bayesian model averaging, and quantile regression. The setting for this study is the Climate Forecasting Applications for Bangladesh (CFAB) forecast system, which over the last decade has been providing operational probabilistic forecasts of severe flooding of the Brahmaputra and Ganges Rivers as part of a humanitarian effort to mitigate the impacts of these events on the country of Bangladesh. The flood forecasting system developed utilizes weather forecast uncertainty information provided by the European Centre for Medium-Range Weather Forecasts (ECMWF) ensemble weather forecasts, rain gauge and satellite-derived precipitation estimates from NASA and NOAA, along with near-real-time river stage observations provided by the Flood Forecasting and Warning Centre of Bangladesh. This paper will discuss both the results of the post-processing comparison study more generally, and also within the unique context of this ongoing flood forecasting effort for Bangladesh.

  7. Effects of fluvial discharges on meiobenthic and macrobenthic variability in the Vistula River prodelta (Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Włodarska-Kowalczuk, Maria; Mazurkiewicz, Mikołaj; Jankowska, Emilia; Kotwicki, Lech; Damrat, Mateusz; Zajączkowski, Marek

    2016-05-01

    The role of environmental variability produced by river discharges in shaping the spatial and seasonal patterns of meiobenthic and macrobenthic communities was studied in the Vistula River (Baltic Sea) prodelta. Seven stations located in the delta front, the plume influence area and the distal zone of the prodelta were visited over the four seasons of 2012. Meiofauna, macrofauna, water (temperature, salinity, and suspended matter) and sediments (grain size, POC, TN, δ15N and δ13C and photosynthetic pigments) were analysed. The seasonal variations in the river discharges (with maximum flows in spring) resulted in a strong temporal variability in the studied environmental characteristics. In the benthic biota, the signals of seasonal variability, if present, were much weaker than spatial zonation. The benthic communities inhabiting the delta front where the main bulk of fluvial materials was deposited were taxonomically impoverished. The richest fauna dwelled within the plume influence area where the physical disturbance ceased and primary marine production was enhanced by river transported nutrients. In the distal zone outside the river influence, the fauna was dominated by deeper dwelling species, and the numbers of individuals and taxa decreased. Factors related to the riverine discharges (i.e., salinity, mineral suspension, POC and δ13C in the water and sediments) were identified as having high correlation with variability in the meiofaunal and macrofaunal community descriptors. Evidently, the interplay of food (i.e., the quantity and quality of organic matter) and disturbance (i.e., the deposition of river transported minerals) constraints shaped the patterns of benthic variability in the prodelta of the second largest river entering the Baltic Sea.

  8. River-discharge variability and trends in southeastern Central Andes since 1940

    NASA Astrophysics Data System (ADS)

    Castino, Fabiana; Bookhagen, Bodo; Strecker, Manfred R.

    2017-04-01

    The southern Central Andes in NW Argentina comprise small to medium drainage basins (102-104 km2) particularly sensitive to climate variability. In this area and in contrast to larger drainage basins such as the Amazon or La Plata rivers, floodplains or groundwater reservoirs either do not exist or are small. This reduces their dampening effect on discharge variability. Previous studies highlighted a rapid discharge increase up to 40% in seven years in the southern Central Andes during the 1970s, inferred to have been associated with the global 1976-77 climate shift. To better understand the processes that drive variations in river discharge in this region, we analyze discharge variability on different timescales, relying on four time series of monthly discharge between 1940 and 2015. Since river discharge in this complex mountain environment results in a pronounced non-stationary and non-linear character, we apply the Hilbert-Huang Transform (HHT) to evaluate non-stationary oscillatory modes of variability and trends. An Ensemble Empirical Mode Decomposition (EEMD) analysis revealed that discharge variability in this region can be decomposed in four quasi-periodic, statistically significant oscillatory modes, associated with timescales varying from 1 to ˜20y. In addition, statistically significant long-term trends show increasing discharge during the period between 1940 and 2015, documenting an intensification of the hydrological cycle during this period. Furthermore, time-dependent intrinsic correlation (TDIC) analysis shows that discharge variability is most likely linked to the phases of the Pacific Decadal Oscillation (PDO) at multi-decadal timescales (˜20y) and, to a lesser degree, to the Tropical South Atlantic SST anomaly (TSA) variability at shorter timescales (˜2-5y). Finally, our results suggest that the rapid discharge increased occurred during the 1970s coincides with the periodic enhancement of discharge mainly linked to the rise of the PDO

  9. Assessments of Environmental Impacts and Beneficial Use of Coalbed Methane Produced Water in the Powder River Basin

    SciTech Connect

    Jeff Morris

    2009-03-15

    Impact on water quality and the beneficial use of the coal bed methane (CBM) produced water are imminent questions to be answered due to the rapidly growing CBM exploration in the Powder River Basin (PRB). The practice of discharging large volumes of water into drainage channels or using it to irrigate rangeland areas has the potential of causing serious problems. The elevated salinity and sodicity in the CBM water may be detrimental to soils, plants and the associated microbial communities. There are limited studies on CBM water characterization; however, a comprehensive understanding of CBM water influence on the local ecosystem is lacking. It is very important that the water applied to soils meets the favorable combination of salinity and sodicity that will allow the plants to grow at good production levels and that will maintain the structure of the soils. The purpose of this study was to access various CBM water treatment technologies and the influence of the treated water on local biogeochemical settings in order to evaluate and identify the proper technologies to treat the CBM produced water from CBM operations, and use it in an environmentally safe manner. Unfortunately, a suitable field site was not identified and the funds for this effort were moved to a different project.

  10. Assessing Geologic Controls on Groundwater Discharge in the Loup River Basin of Nebraska by Using Aerial Thermal-Infrared Imagery

    NASA Astrophysics Data System (ADS)

    Hobza, C. M.; Schepers, A.

    2016-12-01

    Streamflows in the Loup River basin are sensitive to groundwater withdrawals because of the close hydrologic connection between groundwater and surface water. Groundwater discharge contributes more than 90 percent of streamflow in the Loup River basin in the Nebraska Sand Hills. The U.S. Geological Survey, in cooperation with the Upper and Lower Loup Natural Resources Districts, and the Nebraska Environmental Trust, are studying the temporal and spatial characteristics of surface-water/groundwater interaction within the Loup River basin. Streams in the Loup River basin are known to receive a combination of focused discharge (groundwater discharge as springs) and diffuse discharge. To map focused groundwater discharge points, aerial thermal-infrared imagery was collected over two stream reaches prior to onset of ice cover in late 2015, when warm thermal anomalies in stream-surface temperatures indicated areas of focused groundwater discharge. Zones of focused groundwater discharge were detected along the upper South Loup, North Fork of South Loup, and Dismal Rivers. Within the active stream channel, the Dismal River is incising into the Ogallala Formation, which is locally characterized as fine-grained sandstone interbedded with siltstone. Some points of focused discharge along the Dismal River result from local confining beds within the Ogallala Formation that create strong vertical gradients near the stream margin. A series of focused groundwater discharge points was detected along the upper South Loup River where the river has incised into Pliocene-age gravel deposits. Stream surface temperatures from the aerial thermal-infrared imagery were plotted against distance downstream. Results showed a substantial increase in the groundwater component of streamflow originating from diffuse groundwater discharge located upstream from mapped springs.

  11. Effective and bankfull discharges of streams in the Yampa River basin, Colorado and Wyoming

    USGS Publications Warehouse

    Andrews, E.D.

    1980-01-01

    The effective discharge is defined as the increment of discharge that transports the largest fraction of the annual sediment load over a period of years. Increments of the average annual total sediment load transported by various discharges were calculated by the flow-duration, sediment-transport-curve method for 15 gaging stations in the Yampa River basin of Colorado and Wyoming. A total sediment-transport curve was constructed for each gaging station by adding measured instantaneous suspended-sediment discharges to bedload-sediment discharges computed by the Meyer-Peter and Mueller relation. The streamflow durations were compiled from the respective gaging-station records. The quantity of sediment transported by discharges having various frequencies may be computed by combining these two relations. The 15 gaging stations had diverse hydraulic and sediment characteristics. Contributing drainage area ranged from 51.8 to 9,960 km2, and mean-annual discharge ranged from 0.040 to 43.9 m3/s. The median diameter of bed material ranged from 0.4 to 86 mm. Mean-annual sediment load from the drainage basins studied ranged from 500 to 1.3??106 metric tons per year. The effective discharges at the 15 gaging stations were equaled or exceeded on the average of between 1.5 days per year (0.4% of the time) and 11 days per year (3.0% of the time). The recurrence interval of the effective discharges ranged from 1.18 to 3.26 yr. on the annual flood series. To compare the effective discharge with the bankfull discharge, cross-sections were surveyed in a self-formed reach of the channel in the vicinity of each gaging station. The bankfull discharge was defined as the discharge which filled the channel to the level of the floodplain. At all gaging stations, the effective discharge and the bankfull discharge were nearly equal. Thus, the stream channels appear to be adjusted to their effective discharge. ?? 1980.

  12. Geochemical and isotopic characterization of groundwater discharge to the Athabasca River: Insights into sources of salinity

    NASA Astrophysics Data System (ADS)

    Birks, S. J.; Moncur, M. C.; Gibson, J. J.; YI, Y.; Fennell, J.; Jasechko, S.

    2013-12-01

    The Athabasca Oil Sands Region (AOSR) of Northern Alberta represents an important oil reserve for Canada and the world. Identifying impacts of oil sands development to water quality requires indicators of anthropogenic impacts that can be clearly separated from natural background variability. Identifying suitable water quality parameters is complicated in this region because the Athabasca River and its tributaries are incised directly into bitumen saturated sands of the McMurray Formation, as well as other saline Cretaceous and Devonian Formations. Previous work has suggested that the natural input of saline groundwater from these formations may be the the cause for the large increases in chloride observed between Fort McMurray and Old Fort, but more detailed understanding the background inorganic and organic inputs from the different geological units along this stretch of the river will improve our understanding of the natural hydrogeochemical setting of the region and our ability to identify anthropogenic inputs. Here we compile and compare new isotope data collected from various seep sampling campaigns with regional groundwater and river water datasets to better understand the potential sources of dissolved solutes entering the Athabasca River from natural groundwater discharge. Geophysical surveys conducted along the Athabasca River were used to identify areas with elevated terrain conductivity where high salinity groundwater could be discharging to the river. Samples of porewater from the in the hyporheic zone in these areas were obtained using drive point piezometers installed between 1- 3m below the sediment interface. The porewater, groundwater and river water isotope data provide information about the sources of the water (δ18O and δ2H), and solutes (δ34S-SO4, 87Sr/86Sr, δ37Cl, δ11B, δ13C-DIC, δ13C-DOC) as well as information on groundwater ages (3H, 14C). The porewater in the alluvial sediment showed variable degrees of mixing with the overlying

  13. Basin analysis studies of lower Paleozoic rocks, Powder River basin, Wyoming and Montana

    SciTech Connect

    Macke, D.L.

    1988-07-01

    The lower Paleozoic (Cambrian through Mississippian) sedimentary rocks of the Powder River basin represent nearly half of Phanerozoic time, yet they remain virtually unexplored in the subsurface. Rocks of the same age in the Big Horn and Williston basins and in the Central Montana trough have produced much oil and gas, as have the overlying Pennsylvanian strata of the Powder River basin. A synthesis of published stratigraphic information, together with a regional analysis of sedimentary sequences, has been undertaken to evaluate the economic potential of the lower Paleozoic formations. The lack of an economic impetus to study these rocks has hampered the development of precise depositional models for these sequences. Furthermore, the depths of prospective beds, as well as long-standing misconceptions about the regional stratigraphy, have also served to restrain exploration. Stratigraphic studies have documented a succession of marine transgressions and regressions on the flanks of a highland in southeastern Wyoming. The highland persisted as a subdued geographic feature through most of early Paleozoic time, until it rose at the end of the Mississippian. Erosion during the Late Silurian and Devonian removed much of the depositional record in the area, but onlap can be demonstrated with relative certainty for Ordovician and Mississippian rocks. The repetition of sedimentologic features indicates persistent geologic controls in the region and suggests that these paleoenvironments might provide good targets for exploration.

  14. Multi-Seam Well Completion Technology: Implications for Powder River Basin Coalbed Methane Production

    SciTech Connect

    Office of Fossil Energy; National Energy Technology Laboratory

    2003-09-01

    The purpose of this study is to evaluate the potential benefits of applying multiseam [well] completion (MSC) technology to the massive stack of low-rank coals in the Powder River Basin. As part of this, the study objectives are: Estimate how much additional CBM resource would become accessible and technically recoverable--compared to the current practice of drilling one well to drain a single coal seam; Determine whether there are economic benefits associated with MSC technology utilization (assuming its widespread, successful application) and if so, quantify the gains; Briefly examine why past attempts by Powder River Basin CBM operators to use MSC technology have been relatively unsuccessful; Provide the underpinnings to a decision whether a MSC technology development and/or demonstration effort is warranted by DOE. To a great extent, this assessment builds on the previously published study (DOE, 2002), which contains many of the key references that underlie this analysis. It is available on the U.S. Department of Energy, National Energy technology Laboratory, Strategic Center for Natural Gas website (www.netl.doe.gov/scng). It is suggested that readers obtain a copy of the original study to complement the current report.

  15. A field conference on Impacts of coalbed methane development in the Powder River basin, Wyoming

    USGS Publications Warehouse

    Flores, Romeo M.; Stricker, Gary D.; Meyer, Joseph F.; Doll, Thomas E.; Norton, Pierce H.; Livingston, Robert J.; Jennings, M. Craig; Kinney, Scott; Mitchell, Heather; Dunn, Steve

    2001-01-01

    Coalbed methane (CBM) development from the Paleocene Fort Union Formation coal beds in the Powder River Basin in Wyoming has been rapidly expanding since 1993.  During the past ten years the number of CBM producing wells rose to about 4,000 wells as of October, 2000.  About 3,500 of these wells were completed since 1998.  About 13-14 percent of these CBM wells are on Federal lands while the majority are on State and private lands.  More than 50 percent of the lands in the Powder River Basin contains mineral rights owned by the Federal government.  CBM development on Federal lands creates impacts in the basin resulting from associated drilling, facilities, gas gathering systems (e.g., pipeline networks), access roads, and withdrawal and disposal of co-produced water from CBM wells.  The Bureau of Land Management (BLM) assesses the land-use management and impacts of drilling CBM wells on lands where mineral rights are controlled by the Federal government.

  16. Simple statistical models for relating river discharge with precipitation and air temperature—Case study of River Vouga (Portugal)

    NASA Astrophysics Data System (ADS)

    Stoichev, T.; Espinha Marques, J.; Almeida, C. M.; de Diego, A.; Basto, M. C. P.; Moura, R.; Vasconcelos, V. M.

    2017-03-01

    Simple statistical models were developed to relate available meteorological data with daily river discharge (RD) for rivers not influenced by melting of ice and snow. In a case study of the Vouga River (Portugal), the RD could be determined by a linear combination of the recent (P R) and non-recent (P NR) atmospheric precipitation history. It was found that a simple linear model including only P R and P NR cannot account for low RD. The model was improved by including non-linear terms of precipitation that accounted for the water loss. Additional improvement of the models was possible by including average monthly air temperature (T). The best model was robust when up to 60% of the original data were randomly removed. The advantage is the simplicity of the models, which take into account only P R, P NR and T. These models can provide a useful tool for RD estimation from current meteorological data.

  17. Water-quality characteristics and trend analyses for the Tongue, Powder, Cheyenne, and Belle Fourche River drainage basins, Wyoming and Montana, for selected periods, water years 1991 through 2010

    USGS Publications Warehouse

    Clark, Melanie L.

    2012-01-01

    The Powder River structural basin in northeastern Wyoming and southeastern Montana is an area of ongoing coalbed natural gas (CBNG) development. Waters produced during CBNG development are managed with a variety of techniques, including surface impoundments and discharges into stream drainages. The interaction of CBNG-produced waters with the atmosphere and the semiarid soils of the Powder River structural basin can affect water chemistry in several ways. Specific conductance and sodium adsorption ratios (SAR) of CBNG-produced waters that are discharged to streams have been of particular concern because they have the potential to affect the use of the water for irrigation. Water-quality monitoring has been conducted since 2001 at main-stem and tributary sites in the Tongue, Powder, Cheyenne, and Belle Fourche River drainage basins in response to concerns about CBNG effects. A study was conducted to summarize characteristics of stream-water quality for water years 2001–10 (October 1, 2000, to September 30, 2010) and examine trends in specific conductance, SAR, and primary constituents that contribute to specific conductance and SAR for changes through time (water years 1991–2010) that may have occurred as a result of CBNG development. Specific conductance and SAR are the focus characteristics of this report. Dissolved calcium, magnesium, and sodium, which are primary contributors to specific conductance and SAR, as well as dissolved alkalinity, chloride, and sulfate, which are other primary contributors to specific conductance, also are described. Stream-water quality in the Tongue, Powder, Cheyenne, and Belle Fourche River drainage basins was variable during water years 2001–10, in part because of variations in streamflow. In general, annual runoff was less than average during water years 2001–06 and near or above average during water years 2007–10. Stream water of the Tongue River had the smallest specific conductance values, sodium adsorption ratios

  18. The role of discharge variation in scaling of drainage area and food chain length in rivers.

    PubMed

    Sabo, John L; Finlay, Jacques C; Kennedy, Theodore; Post, David M

    2010-11-12

    Food chain length (FCL) is a fundamental component of food web structure. Studies in a variety of ecosystems suggest that FCL is determined by energy supply, environmental stability, and/or ecosystem size, but the nature of the relationship between environmental stability and FCL, and the mechanism linking ecosystem size to FCL, remain unclear. Here we show that FCL increases with drainage area and decreases with hydrologic variability and intermittency across 36 North American rivers. Our analysis further suggests that hydrologic variability is the mechanism underlying the correlation between ecosystem size and FCL in rivers. Ecosystem size lengthens river food chains by integrating and attenuating discharge variation through stream networks, thereby enhancing environmental stability in larger river systems.

  19. The role of discharge variation in scaling of drainage area and food chain length in rivers

    USGS Publications Warehouse

    Sabo, John L.; Finlay, Jacques C.; Kennedy, Theodore A.; Post, David M.

    2010-01-01

    Food chain length (FCL) is a fundamental component of food web structure. Studies in a variety of ecosystems suggest that FCL is determined by energy supply, environmental stability, and/or ecosystem size, but the nature of the relationship between environmental stability and FCL, and the mechanism linking ecosystem size to FCL, remain unclear. Here we show that FCL increases with drainage area and decreases with hydrologic variability and intermittency across 36 North American rivers. Our analysis further suggests that hydrologic variability is the mechanism underlying the correlation between ecosystem size and FCL in rivers. Ecosystem size lengthens river food chains by integrating and attenuating discharge variation through stream networks, thereby enhancing environmental stability in larger river systems.

  20. Continuous river discharge monitoring with bottom-mounted current profilers at narrow tidal estuaries

    NASA Astrophysics Data System (ADS)

    Garel, E.; D'Alimonte, D.

    2017-02-01

    The objective of this study is to verify whether accurate and continuous estimates of freshwater discharge at the mouth of a narrow estuary with a single channel can be obtained from a bottom-mounted current profiler (ADCP). The focus is on moderate- to high-discharge events that significantly affect the water circulation corresponding to low river flow conditions. Observations at the Guadiana Estuary (southern Iberia) indicate lateral subtidal flow variability, constant cross-channel area, and quasi-steady response of the axial velocity to discharge events. Based on the concept of maximum entropy, the mean and maximum channel velocities were related by a constant ratio, Ω, using data from three cross-channel surveys. This relationship was then used to estimate the freshwater discharge at the mouth based on the maximum velocity obtained from the detided ADCP velocity profiles. This approach was possible because the ADCP was deployed near the position of maximum current velocity, that is, over the deepest part of the channel. The results show good correspondence with observations, indicating that the entropy model can complete or substitute the records from upstream gauged stations that do not include the contribution from downstream tributaries. A Multilayer Perceptron neural net (MLP) based on the entropy approach was then implemented with the purpose of estimating the discharge when Ω is unknown. This latter analysis showsthat the relationship between maximum velocity and discharge is quasi-stationary. Consequently, the MLP can successfully estimate freshwater runoff if the training data represent all statistical properties of the river discharge dynamics. The results also indicate that Ω may vary not only with concomitant hydrographic conditions, but also with the recent (i.e., several days prior) discharge magnitude.

  1. The Influence of Dam Discharge Regime and Canyon Orientation on Ecosystem Metabolism in the Colorado River

    NASA Astrophysics Data System (ADS)

    Kennedy, T. A.; Tietjen, T.; Wright, S.

    2005-05-01

    Since the closure of Glen Canyon Dam and the beginning of flow regulation of the Colorado River in Grand Canyon in 1963, considerable efforts have been directed toward understanding the aquatic ecology of this altered ecosystem. Understanding what controls resource availability has been a central focus of these efforts because the Colorado River supports populations of sport fish and endangered humpback chub, both of which appear to be strongly resource limited. There is evidence that dam discharge regime and canyon orientation influence algal standing crop due to their effects on water velocity (scour) and solar insolation, respectively. We explored whether these physical factors influenced rates of primary production and ecosystem respiration, two different metrics of resource availability, in the clear tailwater section of the Colorado River by conducting whole system metabolism measurements across a range of discharge regimes and in reaches with different orientation (i.e. N-S vs. E-W). We found that while both discharge regime and canyon orientation influence rates of primary production, seasonal changes in light availability appear to have a far stronger influence on rates of primary production in the Colorado River. Water temperature appeared to be the main driver of ecosystem respiration.

  2. Impact of river discharge on the California coastal ocean circulation and variability

    NASA Astrophysics Data System (ADS)

    Leiva, J.; Chao, Y.; Farrara, J. D.; Zhang, H.

    2016-12-01

    A real-time California coastal ocean nowcast and forecast system is used to quantify the impact of river discharge on the California coastal ocean circulation and variability. River discharge and freshwater runoff is monitored by an extensive network of stream gages maintained through the U.S. Geological Survey, that offers archived stream flow records as well as real-time datasets. Of all the rivers monitored by the USGS, 25 empty into the Pacific Ocean and contribute a potential source of runoff data. Monthly averages for the current water year yield discharge estimates as high as 6,000 cubic meters per second of additional freshwater input into our present model. Using Regional Ocean Modeling System (ROMS), we performed simulations from October 2015 to May 2016 with and without the river discharge. Results of these model simulations are compared with available observations including both in situ and satellite. Particular attention is paid to the salinity simulation. Validation is done with comparisons to sea glider data available through Oregon State University and UC San Diego, which provides depth profiles along the California coast during this time period. Additional validation is performed through comparisons with sea surface salinity measurements from the Soil Moisture and Ocean Salinity (SMOS) mission. Continued testing for previous years, e.g. between 2011 and 2015, is being made using the Aquarius sea surface salinity data. Discharge data collected by the USGS stream gages provides a necessary source of freshwater input that must be accounted for. Incorporating a new runoff source produces a more robust model that generates improved forecasts. Following validation with available sea glider and satellite data, the enhanced model can be adapted to real-time forecasting.

  3. River Discharge and Bathymetry Estimation from Hydraulic Inversion of Surface Currents and Water Surface Elevation Observations

    NASA Astrophysics Data System (ADS)

    Simeonov, J.; Holland, K. T.

    2015-12-01

    We developed an inversion model for river bathymetry and discharge estimation based on measurements of surface currents, water surface elevation and shoreline coordinates. The model uses a simplification of the 2D depth-averaged steady shallow water equations based on a streamline following system of coordinates and assumes spatially uniform bed friction coefficient and eddy viscosity. The spatial resolution of the predicted bathymetry is related to the resolution of the surface currents measurements. The discharge is determined by minimizing the difference between the predicted and the measured streamwise variation of the total head. The inversion model was tested using in situ and remote sensing measurements of the Kootenai River east of Bonners Ferry, ID. The measurements were obtained in August 2010 when the discharge was about 223 m3/s and the maximum river depth was about 6.5 m. Surface currents covering a 10 km reach with 8 m spatial resolution were estimated from airborne infrared video and were converted to depth-averaged currents using acoustic Doppler current profiler (ADCP) measurements along eight cross-stream transects. The streamwise profile of the water surface elevation was measured using real-time kinematic GPS from a drifting platform. The value of the friction coefficient was obtained from forward calibration simulations that minimized the difference between the predicted and measured velocity and water level along the river thalweg. The predicted along/cross-channel water depth variation was compared to the depth measured with a multibeam echo sounder. The rms error between the measured and predicted depth along the thalweg was found to be about 60cm and the estimated discharge was 5% smaller than the discharge measured by the ADCP.

  4. Synoptic Discharge, Water-Property, and pH Measurements for Muddy River Springs Area and Muddy River, Nevada, February 7, 2001

    USGS Publications Warehouse

    Beck, David A.; Wilson, Jon W.

    2006-01-01

    On February 7, 2001, synoptic discharge measurements at selected sites along the Muddy River in Nevada, indicated three trends in discharge resulting from contributions of spring discharge, influences of diversionary flow, and contributions from shallow ground water. Effects from diversionary and tributary flow were local in nature and resulted in a net gain of 2.6 cubic feet per second throughout the measured reach. The minor increase in discharge may be the result of contributions from ground-water flow and measurement error. Comparison of 1963 and 2001 discharge measurements within the Muddy River Springs area indicated that discharge rates and trends from these source waters were similar. Along the mainstem of the Muddy River, water-temperature measurements indicated a net decrease of 8.8 degrees Celsius. Water samples collected and analyzed for specific conductance indicated a net increase of 390 microsiemens per centimeter at 25 degrees Celsius, whereas pH measurements remained relatively constant.

  5. A Particular River-Whiting Phenomenon Caused by Discharge of Hypolimnetic Water from a Stratified Reservoir

    PubMed Central

    Chen, Jingan; Yang, Haiquan; Zhang, David Dian; Xu, Dan; Luo, Jing; Wang, Jingfu

    2015-01-01

    A particular river-whiting phenomenon occurred in the early 2000s in the Xiaoche River and since then it has been reoccurring from June to November each year. Residents were surprised by this phenomenon and worried about it. This study was designed to reveal the forming mechanism of the river-whiting phenomenon. A comparison of T, EC, ORP, DO, TDS and δ34S in the culvert water and discharge pipe water with that in the water column of Aha Reservoir strongly indicated that the culvert water and discharge pipe water derived primarily from the hypolimnetic reservoir water. When the hypolimnetic water enriched in SO42- and H2S, through seepage from the penstock, flows into the Xiaoche River, the water's supersaturation degree with respect to CaSO4 is increased as a result of increased temperature and DO, thus colloid CaSO4 can be formed. This is the essential cause of the river-whiting phenomenon. The sources of high concentrations of SO42- and H2S in hypolimnetic water include not only direct SO42- and H2S input of acid mine drainage as a result of irrational coal mining in the watershed, but also the sulfur-enriched surface sediments which may release H2S through the sulfate reduction processes. The contaminated sediment has acted as an important contamination source for sulfur to the overlying water in Aha Reservoir. There are more than 50,000 large dams in the world until now. With the increase of reservoir age and the persistent accumulation of pollutants within the reservoir system, discharged hypolimnetic water may contain high levels of pollutants and lead to unpredicted disasters. More investigations are needed to illuminate the water quality condition of discharge water from reservoirs and estimate its impacts on the downstream eco-environment. PMID:26361219

  6. Intercomparison of global river discharge simulations focusing on dam operation—multiple models analysis in two case-study river basins, Missouri-Mississippi and Green-Colorado

    NASA Astrophysics Data System (ADS)

    Masaki, Yoshimitsu; Hanasaki, Naota; Biemans, Hester; Müller Schmied, Hannes; Tang, Qiuhong; Wada, Yoshihide; Gosling, Simon N.; Takahashi, Kiyoshi; Hijioka, Yasuaki

    2017-05-01

    We performed an intercomparison of river discharge regulated by dams under four meteorological forcings among five global hydrological models for a historical period by simulation. This is the first global multimodel intercomparison study on dam-regulated river flow. Although the simulations were conducted globally, the Missouri-Mississippi and Green-Colorado Rivers were chosen as case-study sites in this study. The hydrological models incorporate generic schemes of dam operation, not specific to a certain dam. We examined river discharge on a longitudinal section of river channels to investigate the effects of dams on simulated discharge, especially at the seasonal time scale. We found that the magnitude of dam regulation differed considerably among the hydrological models. The difference was attributable not only to dam operation schemes but also to the magnitude of simulated river discharge flowing into dams. That is, although a similar algorithm of dam operation schemes was incorporated in different hydrological models, the magnitude of dam regulation substantially differed among the models. Intermodel discrepancies tended to decrease toward the lower reaches of these river basins, which means model dependence is less significant toward lower reaches. These case-study results imply that, intermodel comparisons of river discharge should be made at different locations along the river's course to critically examine the performance of hydrological models because the performance can vary with the locations.

  7. Water discharge affects Atlantic salmon Salmo salar smolt production: a 27 year study in the River Orkla, Norway.

    PubMed

    Hvidsten, N A; Diserud, O H; Jensen, A J; Jensås, J G; Johnsen, B O; Ugedal, O

    2015-01-01

    A model that explains 48% of the annual variation in Atlantic salmon Salmo salar smolt production in the River Orkla, Norway, has been established. This variation could be explained by egg deposition, minimum daily discharge during the previous winter and minimum weekly discharge during the summer 3 years before smolt migration. All coefficients in the model were positive, which indicates that more eggs and higher minimum discharge levels during the winter before smolt migration and the summer after hatching benefit smolt production. Hence, when the spawning target of the river is reached, the minimum levels of river discharge, in both winter and summer, are the main bottlenecks for the parr survival, and hence for smolt production. The River Orkla was developed for hydropower production in the early 1980s by the construction of four reservoirs upstream of the river stretch accessible to S. salar. Although no water has been removed from the catchment, the dynamics of water flow has been altered, mainly by increasing discharges during winter and reducing spring floods. In spite of the higher than natural winter discharges, minimum winter discharge is still a determinant of smolt production. Hence, in regulated rivers, the maintenance of discharges to ensure that they are as high as possible during dry periods is an important means of securing high S. salar smolt production.

  8. Sediment discharge in the Santa Clara River Basin, Ventura and Los Angeles Counties, California

    USGS Publications Warehouse

    Williams, Rhea P.

    1979-01-01

    Sediment data collected in the Santa Clara River in California basin, during the 1967-75 water years were analyzed to determine the particle size and quantity of sediment transported past three gaging stations. The total sediment discharge of the basin , computed from records of Santa Clara River at Montalvo for water years 1968-75, was 63.5 million tons, of which 59.5 million tons was carried in suspension and an estimated 4 million tons was transported as unsampled sediment discharge. About 17.7 million tons, or 28 percent of the total sediment discharge, was coarse sediment (particles larger than 0.062 millimeter). Most of the sediment was transported during only a few days of floodflow each year. During the 1968-75 water years, approximately 55 percent of the total sediment was transported in 2 days and 92 percent was transported in 53 days. The long-term (1928-75) average annual sediment discharge of the Santa Clara River at Montalvo is estimated at 3.67 million tons. Of that quantity, 2.58 million tons consisted of fine sediment and 1.09 million tons consisted of coarse sediment. A sediment budget for the Santa Clara River basin was estimated for sediment discharges under both natural and actual conditions. The major difference between natural and actual sediment discharges of the Santa Clara River basin is the sediment intercepted upstream from Lake Piru. The combined trap efficiency of Lake Piru and Pyramid Lake approaches 100 percent. Sediment deposited in these reservoirs resulted in about a 6-percent reduction of sediment to the Santa Clara River basin during the historical period (1928-75) and a 12-percent reduction during the period most affected by dams (1953-75). Sediment losses to the basin by gravel mining, diversion of flows, and interception of sediment in the Castaic Creek basin resulted in additional reductions of 2 percent during the period 1928-75 and 4 percent during the period 1953-75. (Kosco-USGS)

  9. Climate change impacts on Yangtze River discharge at the Three Gorges Dam

    NASA Astrophysics Data System (ADS)

    Birkinshaw, Steve J.; Guerreiro, Selma B.; Nicholson, Alex; Liang, Qiuhua; Quinn, Paul; Zhang, Lili; He, Bin; Yin, Junxian; Fowler, Hayley J.

    2017-04-01

    The Yangtze River basin is home to more than 400 million people and contributes to nearly half of China's food production. Therefore, planning for climate change impacts on water resource discharges is essential. We used a physically based distributed hydrological model, Shetran, to simulate discharge in the Yangtze River just below the Three Gorges Dam at Yichang (1 007 200 km2), obtaining an excellent match between simulated and measured daily discharge, with Nash-Sutcliffe efficiencies of 0.95 for the calibration period (1996-2000) and 0.92 for the validation period (2001-2005). We then used a simple monthly delta change approach for 78 climate model projections (35 different general circulation models - GCMs) from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to examine the effect of climate change on river discharge for 2041-2070 for Representative Concentration Pathway 8.5. Projected changes to the basin's annual precipitation varied between -3.6 and +14.8 % but increases in temperature and consequently evapotranspiration (calculated using the Thornthwaite equation) were projected by all CMIP5 models, resulting in projected changes in the basin's annual discharge from -29.8 to +16.0 %. These large differences were mainly due to the predicted expansion of the summer monsoon north and west into the Yangtze Basin in some CMIP5 models, e.g. CanESM2, but not in others, e.g. CSIRO-Mk3-6-0. This was despite both models being able to simulate current climate well. Until projections of the strength and location of the monsoon under a future climate improve, large uncertainties in the direction and magnitude of future change in discharge for the Yangtze will remain.

  10. Specific Conductivity Synoptic Surveys to Map Groundwater-Surface Water Discharges in a Lowland River

    NASA Astrophysics Data System (ADS)

    Pai, H.; Villamizar, S. R.; Harmon, T. C.

    2014-12-01

    Quantifying distributed groundwater-surface water (GW-SW) discharges at the watershed scale is a challenging but important aspect of tracking nonpoint-source pollutants and their potential impacts on riverine water quality. This work analyzes high spatiotemporal longitudinal river sampling along a 38 km reach of the lower Merced River (LMR) in California's San Joaquin River (SJR) watershed and estimates GW-SW discharges using a simple discretized mixing model. The LMR flow is dam-controlled upstream and has several distributed surface discharges from SW diversions, SW canal inputs, and potential GW discharges influenced by the surrounding agricultural and municipal landscapes. We collected longitudinal datasets covering a wide range of flows (1.3 to 150 m3/s), sampling georeferenced water specific conductance (SC) at intervals of less than 1 minute. Whole-reach gradients of SW specific conductance (SC), representing GW-SW salinity loading (mS/cm/river km), decreased in proportion to the flow and stage, indicating either (1) a simple dilution effect or (2) reduced GW-SW discharges due to a reduced GW-SW hydraulic gradient at higher stages. With respect to distributed discharges, local gradients were significant (p < 0.05), with estimated local salinity loads varying from -0.4 to 8.9 mS/cm/river km for the LMR conditions. Using local groundwater salinity estimates, we inverted a discretized mixing model to estimate distributed groundwater fluxes. Summation of the fluxes agreed well with stream gage estimates. However, local flux estimates were nonuniform, with mid-reach values consistently increasing to a maximum value at intermediate stream flows, then decreasing for greater flows. Causes for this behavior remain uncertain but may be due to one or more of the following: (1) uncertainty in the groundwater salinity data, (2) salinity reduction in the hyporheic zone (e.g., denitrification), and (3) access to preferential GW-SW flowpaths at intermediate flows and stages

  11. Morphometric Discharge Relationships in the Cosumnes River Drainage Basin, Sierra Nevada, California

    NASA Astrophysics Data System (ADS)

    Cornwell, K.; Meyer, R.

    2002-12-01

    Hydrographic similarities between disparate gaging stations in the Consumnes River drainage basin suggest that it may be possible to extend stream gage records in areas with limited or missing records. This has led to an analysis of the relationship between recorded daily discharge values and bankfull channel conditions in the basin using USGS gage data from three sites in the basin [11335000 Cosumnes River at Michigan Bar (MBAR - period of record 1907-2002), 11333500 North Fork Cosumnes near El Dorado (NFELDO - period of record 1911-1941 and 1948-1987) and the 11334200 Middle Fork Cosumnes near Somerset (MFSOM - period of record 1957-1971)], 3-day mean discharge values and bank-full conditions (discharge recurrence interval of ~1.5 years) were calculated. Utilizing the bank-full discharge of the mainstem gage (MBAR) as a threshold, we compared discharge values between MBAR and two of its tributaries (NFELDO and MFSOM) and observed strong linear trends in the data sets. Mathematical expressions were derived to characterize the relations between the individual tributaries and the mainstem gage. When calibrated against the complete gage records of the tributaries we encountered overall error rates of less than 5 percent from both tributary data sets. This suggests that it is possible to extend stream gage records in areas with limited existing records or where occasional activiation and de-activation of gage sites result in incomplete long-term records.

  12. Hydrogeologic framework of the uppermost principal aquifer systems in the Williston and Powder River structural basins, United States and Canada

    USGS Publications Warehouse

    Thamke, Joanna N.; LeCain, Gary D.; Ryter, Derek W.; Sando, Roy; Long, Andrew J.

    2014-01-01

    Regionally, water in the lower Tertiary and Upper Cretaceous aquifer systems flows in a northerly or northeasterly direction from the Powder River structural basin to the Williston structural basin. Groundwater flow in the Williston structural basin generally is easterly or northeasterly. Flow in the uppermost hydrogeologic units generally is more local and controlled by topography where unglaciated in the Williston structural basin than is flow in the glaciated part and in underlying aquifers. Groundwater flow in the Powder River structural basin generally is northerly with local variations greatest in the uppermost aquifers. Groundwater is confined, and flow is regional in the underlying aquifers.

  13. Evaluation of seepage and discharge uncertainty in the middle Snake River, southwestern Idaho

    USGS Publications Warehouse

    Wood, Molly S.; Williams, Marshall L.; Evetts, David M.; Vidmar, Peter J.

    2014-01-01

    The U.S. Geological Survey, in cooperation with the State of Idaho, Idaho Power Company, and the Idaho Department of Water Resources, evaluated seasonal seepage gains and losses in selected reaches of the middle Snake River, Idaho, during November 2012 and July 2013, and uncertainty in measured and computed discharge at four Idaho Power Company streamgages. Results from this investigation will be used by resource managers in developing a protocol to calculate and report Adjusted Average Daily Flow at the Idaho Power Company streamgage on the Snake River below Swan Falls Dam, near Murphy, Idaho, which is the measurement point for distributing water to owners of hydropower and minimum flow water rights in the middle Snake River. The evaluated reaches of the Snake River were from King Hill to Murphy, Idaho, for the seepage studies and downstream of Lower Salmon Falls Dam to Murphy, Idaho, for evaluations of discharge uncertainty. Computed seepage was greater than cumulative measurement uncertainty for subreaches along the middle Snake River during November 2012, the non-irrigation season, but not during July 2013, the irrigation season. During the November 2012 seepage study, the subreach between King Hill and C J Strike Dam had a meaningful (greater than cumulative measurement uncertainty) seepage gain of 415 cubic feet per second (ft3/s), and the subreach between Loveridge Bridge and C J Strike Dam had a meaningful seepage gain of 217 ft3/s. The meaningful seepage gain measured in the November 2012 seepage study was expected on the basis of several small seeps and springs present along the subreach, regional groundwater table contour maps, and results of regional groundwater flow model simulations. Computed seepage along the subreach from C J Strike Dam to Murphy was less than cumulative measurement uncertainty during November 2012 and July 2013; therefore, seepage cannot be quantified with certainty along this subreach. For the uncertainty evaluation, average

  14. Evaluation of the depth-integration method of measuring water discharge in large rivers

    USGS Publications Warehouse

    Moody, J.A.; Troutman, B.M.

    1992-01-01

    The depth-integration method oor measuring water discharge makes a continuos measurement of the water velocity from the water surface to the bottom at 20 to 40 locations or verticals across a river. It is especially practical for large rivers where river traffic makes it impractical to use boats attached to taglines strung across the river or to use current meters suspended from bridges. This method has the additional advantage over the standard two- and eight-tenths method in that a discharge-weighted suspended-sediment sample can be collected at the same time. When this method is used in large rivers such as the Missouri, Mississippi and Ohio, a microwave navigation system is used to determine the ship's position at each vertical sampling location across the river, and to make accurate velocity corrections to compensate for shift drift. An essential feature is a hydraulic winch that can lower and raise the current meter at a constant transit velocity so that the velocities at all depths are measured for equal lengths of time. Field calibration measurements show that: (1) the mean velocity measured on the upcast (bottom to surface) is within 1% of the standard mean velocity determined by 9-11 point measurements; (2) if the transit velocity is less than 25% of the mean velocity, then average error in the mean velocity is 4% or less. The major source of bias error is a result of mounting the current meter above a sounding weight and sometimes above a suspended-sediment sampling bottle, which prevents measurement of the velocity all the way to the bottom. The measured mean velocity is slightly larger than the true mean velocity. This bias error in the discharge is largest in shallow water (approximately 8% for the Missouri River at Hermann, MO, where the mean depth was 4.3 m) and smallest in deeper water (approximately 3% for the Mississippi River at Vickbsurg, MS, where the mean depth was 14.5 m). The major source of random error in the discharge is the natural

  15. Influence of river discharge and ocean currents on coastal optical properties

    NASA Astrophysics Data System (ADS)

    Cherukuru, Nagur; Brando, Vittorio E.; Schroeder, Thomas; Clementson, Lesley A.; Dekker, Arnold G.

    2014-08-01

    The variability in the optical properties of a coastal region influenced by river runoff and multiple ocean currents in a southern hemisphere setting has been studied. The study area, Tasmanian coastal waters, is influenced by subtropical currents such as the East Australian Current (EAC) and the Zeehan Current (ZC) mix with cooler sub-Antarctic water (SAW). Freshwater discharges from rivers around the island and their mixing with the ocean currents also influence Tasmanian coastal waters. This study was performed to understand the influence of hydrodynamic processes on coastal optical properties and underwater light propagation. Physical, biogeochemical and optical properties were measured in Tasmanian coastal water during the austral autumn of 2007. In this study we found that physical properties have a good correlation with optical properties indicating the role played by hydrodynamic processes in distribution of optically active substances, optical properties of the water mass and underwater light propagation. Analysis of in situ salinity and temperature confirmed the presence of relatively cooler ZC in the South-West region, a cooler mixture of the ZC and SAW in the South-East, warm and saline EAC waters along the East coast and relatively cooler and fresh Bass straight waters along the North coast. In Tasmanian coastal waters light absorption in the water column is controlled by Coloured Dissolved Organic Matter (CDOM) with regionally varying contributions from Non-Algal Particulate (NAP) matter and phytoplankton. Absorption due to CDOM and NAP show a conservative mixing behaviour indicating that these biogeochemical components were delivered by the river and diluted in the coastal water. Suspended particulate matter in Tasmanian coastal water are highly scattering in nature and the beam attenuation is mainly due to light scattering. Variability in probability of light backscattering was mainly due to varying availability of non-algal particulate matter in

  16. Watershed land use influences on river discharge and channel characteristics across northern New Jersey

    NASA Astrophysics Data System (ADS)

    Galster, J. C.; Palmer, K.; Birrer, M.; Espinosa, S.; Pope, G. A.; Feng, H.; Wu, M. S.

    2012-12-01

    River characteristics such as sediment size, channel dimensions, and discharges can be strongly controlled by watershed land use. This project investigated three watersheds in northern New Jersey with varying degrees of forested, agriculture, and urban land uses to determine the effects of land use on these rivers. The watersheds are the Flatbrook, the Wallkill, and the Rockaway rivers and are predominantly forested, forested/agricultural, and forested/urban respectively. Eight sites across these fourth and fifth-order watersheds were investigated including: 1) the grain size using the Wolman pebble count method, 2) channel dimensions (slope, width, depth) with a total station, and 3) channel stability using the rapid geomorphic assessment (RGA). Channel width changes from 1930 to present were determined using historic aerial photographs, and river discharge characteristics were compiled using custom software to determine the flashiness (as measured by the Reynolds-Baker Index) and the Baseflow Index. The three adjacent watersheds have minimal variations in potential confounding variables such as watershed slope, climate, and precipitation, allowing for the isolation of the effects of land use changes. While some of the general relationship between how land use changes affect rivers (e.g., urban streams typically have larger grain sizes and flashier discharges), studies such as this one are important in determining how rivers respond locally. Across the studied watersheds, forested land uses are positively associated with rapid geomorphic assessments scores, indicating the influence of upstream land use and the importance of vegetation. Forested land use is also associated with efficient discharges as measured by hydraulic radius, although there were not significant changes in channel width from 1930 to present. The flashiness of all rivers has increased over time while the baseflow index has decreased, which may be a climatic signal as opposed to being influenced

  17. Including stage-dependent roughness coefficient in algorithms to estimate river discharge from remotely sensed water elevation, width, and slope

    NASA Astrophysics Data System (ADS)

    Durand, M. T.; Gleason, C. J.; Bjerklie, D. M.; Garambois, P. A.; Smith, L. C.; Roux, H.; Rodriguez, E.; Tuozzolo, S.

    2016-12-01

    The Surface Water and Ocean Topography (SWOT) mission will measure water elevation, width, and slope for global rivers wider than 100 m, and perhaps as narrow as 50 m. Inference of river discharge from the measurements requires either prior information about river flows, or solving an ill-posed inverse problem to infer unmeasured river hydraulic quantities, often using Manning's equation. Previous studies have shown that reach averaging Manning's equation introduces flow-dependent variations in the effective roughness coefficient. We present a dataset of model-derived effective roughness coefficient timeseries, and power-law type models for how the roughness coefficient varies with flow and with stage, for ten rivers. We then provide side-by-side comparisons of discharge algorithm performance including and omitting the variable roughness coefficient. We explore empirical and physically-based methods of approximating the parameters in the roughness coefficient model. Finally, we characterize the expected discharge accuracy from these approaches in various types of rivers.

  18. Methods to estimate annual mean spring discharge to the Snake River between Milner Dam and King Hill, Idaho

    USGS Publications Warehouse

    Kjelstrom, L.C.

    1995-01-01

    Many individual springs and groups of springs discharge water from volcanic rocks that form the north canyon wall of the Snake River between Milner Dam and King Hill. Previous estimates of annual mean discharge from these springs have been used to understand the hydrology of the eastern part of the Snake River Plain. Four methods that were used in previous studies or developed to estimate annual mean discharge since 1902 were (1) water-budget analysis of the Snake River; (2) correlation of water-budget estimates with discharge from 10 index springs; (3) determination of the combined discharge from individual springs or groups of springs by using annual discharge measurements of 8 springs, gaging-station records of 4 springs and 3 sites on the Malad River, and regression equations developed from 5 of the measured springs; and (4) a single regression equation that correlates gaging-station records of 2 springs with historical water-budget estimates. Comparisons made among the four methods of estimating annual mean spring discharges from 1951 to 1959 and 1963 to 1980 indicated that differences were about equivalent to a measurement error of 2 to 3 percent. The method that best demonstrates the response of annual mean spring discharge to changes in ground-water recharge and discharge is method 3, which combines the measurements and regression estimates of discharge from individual springs.

  19. Sustain and address discharge characteristics of AC-PDP with MgO surface coated by MgO nano crystal powders.

    PubMed

    Kim, J H; Park, C S; Park, H D; Tae, H S; Lee, S H

    2013-05-01

    This paper examined the sustain and address discharge characteristics of ac-PDPs with MgO surface coated by MgO nano crystal powders. The MgO nano crystal powder was deposited by about 5% on the MgO surface by using the spray method. To investigate the effects of the partial addition of MgO nano crystal powders on the sustain discharge as well as the address discharge, the luminance, IR spectra of 823, 828 nm, cathodoluminance, and firing voltage were measured with the measurement of the address delay times and wall voltage variation in the 42-inch ac-PDP module with a high Xe content of 17%. As a result, the statistical delay characteristics were improved considerably especially under the low panel temperature of -5 degrees C for the MgO surface with MgO nano crystal powder. However, both MgO surfaces with and without the MgO nano crystal powder showed almost similar sustain and address discharge characteristics except the statistical delay characteristics.

  20. The offshore export of sand during exceptional discharge from California rivers

    USGS Publications Warehouse

    Warrick, Jonathan A.; Barnard, Patrick L.

    2012-01-01

    Littoral cells along active tectonic margins receive large inputs of sand and gravel from coastal watersheds and commonly lose this sediment to submarine canyons. One hypothesis is that the majority of coarse (sand and gravel) river sediment discharge will be emplaced within and immediately “resupply” local littoral cells. A competing hypothesis is that the infrequent, large floods that supply the majority of littoral sediment may discharge water-sediment mixtures within negatively buoyant hyperpycnal plumes that transport sediment offshore of the littoral cell. Here we summarize pre- and post-flood surveys of two wave-dominated California (United States) river deltas during record to near-record floods to help evaluate these hypotheses: the 1982–1983 delta at the San Lorenzo River mouth and the 2005 delta at the Santa Clara River mouth. Flood sedimentation at both deltas resulted in several meters of aggradation and hundreds of meters of offshore displacement of isobaths. One substantial difference between these deltas was the thick (>2 m) aggradation of sand on the inner shelf of the Santa Clara River delta that contained substantial amounts (∼50%) of littoral-grade sediment. Once deposited on the inner shelf, only a fraction (∼20%) of this river sand was observed to migrate toward the beach over the following 5 yr. Furthermore, simple hypopycnal plume behavior could not explain deposition of this sand on the inner shelf. Thus, during an exceptional flood a substantial amount of littoral-grade sand was exported offshore of the littoral system at the Santa Clara River mouth—likely from hyperpycnal plume processes—and was deposited on the inner shelf.

  1. Comparative evaluation of ensemble Kalman filter, particle filter and variational techniques for river discharge forecast

    NASA Astrophysics Data System (ADS)

    Hirpa, F. A.; Gebremichael, M.; LEE, H.; Hopson, T. M.

    2012-12-01

    Hydrologic data assimilation techniques provide a means to improve river discharge forecasts through updating hydrologic model states and correcting the atmospheric forcing data via optimally combining model outputs with observations. The performance of the assimilation procedure, however, depends on the data assimilation techniques used and the amount of uncertainty in the data sets. To investigate the effects of these, we comparatively evaluate three data assimilation techniques, including ensemble Kalman filter (EnKF), particle filter (PF) and variational (VAR) technique, which assimilate discharge and synthetic soil moisture data at various uncertainty levels into the Sacramento Soil Moisture accounting (SAC-SMA) model used by the National Weather Service (NWS) for river forecasting in The United States. The study basin is Greens Bayou watershed with area of 178 km2 in eastern Texas. In the presentation, we summarize the results of the comparisons, and discuss the challenges of applying each technique for hydrologic applications.

  2. Freshwater fluxes in the Berau estuary and shelf during peak river discharge conditions

    NASA Astrophysics Data System (ADS)

    Van Der Vegt, M.; Tarya, A.; Hoitink, A.

    2011-12-01

    The Berau Continental Shelf is located close to the Equator in the Indonesian Archipelago, hosting a complex of coral reefs and atolls along its oceanic edge. It is important to understand how river water, sediments, and other materials derived from land are carried to reefs by physical mechanisms, since they can have beneficial as well as negative effects. Furthermore, at several of the atolls unique seagrass meadows are found. These ecosystems need exclusively marine conditions and are intolerant to freshwater. In the Berau Continental shelf much uncertainty remains about how much of the riverine water reaches the reefs and the atolls. In a recent study we showed that tides are the main contributor to the spreading of freshwater at the Berau Continental Shelf under average conditions: relatively small river discharge, weak winds, strong tides. A three-dimensional model (ECOMSED) was calibrated and validated with observational data collected in the context of the East Kalimantan Research Programme. Data-model comparison showed high skill scores and small systematic errors. Model analysis has shown that tides effect the plume by causing vertical mixing, by stratifying the plume due to tidal straining and by transporting freshwater. This causes the depth-integrated freshwater transport to be mainly north-eastward, toward the barrier reef. Under these average conditions freshwater does not reach the atolls. The main aim of this study is to study plume dynamics at the Berau shelf during peak river discharge and peak wind conditions. Because the Berau delta is urbanizing rapidly increasing peak river discharges and sediment loads are expected. In addition, although the yearly mean wind is small, peak wind events concurrent with peak floods might push the stratified top layer of the water column towards the reefs and atolls. Using the results of a hydrological model we estimated realistic peak values of the river discharge based on scenarios for the economical

  3. An automated system to simulate the River discharge in Kyushu Island using the H08 model

    NASA Astrophysics Data System (ADS)

    Maji, A.; Jeon, J.; Seto, S.

    2015-12-01

    Kyushu Island is located in southwestern part of Japan, and it is often affected by typhoons and a Baiu front. There have been severe water-related disasters recorded in Kyushu Island. On the other hand, because of high population density and for crop growth, water resource is an important issue of Kyushu Island.The simulation of river discharge is important for water resource management and early warning of water-related disasters. This study attempts to apply H08 model to simulate river discharge in Kyushu Island. Geospatial meteorological and topographical data were obtained from Japanese Ministry of Land, Infrastructure, Transport and Tourism (MLIT) and Automated Meteorological Data Acquisition System (AMeDAS) of Japan Meteorological Agency (JMA). The number of the observation stations of AMeDAS is limited and is not quite satisfactory for the application of water resources models in Kyushu. It is necessary to spatially interpolate the point data to produce grid dataset. Meteorological grid dataset is produced by considering elevation dependence. Solar radiation is estimated from hourly sunshine duration by a conventional formula. We successfully improved the accuracy of interpolated data just by considering elevation dependence and found out that the bias is related to geographical location. The rain/snow classification is done by H08 model and is validated by comparing estimated and observed snow rate. The estimates tend to be larger than the corresponding observed values. A system to automatically produce daily meteorological grid dataset is being constructed.The geospatial river network data were produced by ArcGIS and they were utilized in the H08 model to simulate the river discharge. Firstly, this research is to compare simulated and measured specific discharge, which is the ratio of discharge to watershed area. Significant error between simulated and measured data were seen in some rivers. Secondly, the outputs by the coupled model including crop growth

  4. Cyclic powder formation during pulsed injection of hexamethyldisiloxane in an axially asymmetric radiofrequency argon discharge

    SciTech Connect

    Despax, B.; Makasheva, K.; Caquineau, H.

    2012-11-01

    A new approach of periodic production of dusty plasma consisting of pulsed injection of hexamethyldisiloxane (HMDSO) in argon axially asymmetric radiofrequency (RF) discharge was investigated in this work. The range of plasma operating conditions in which this dusty plasma can exist was closely examined. The obtained results clearly show that a net periodicity in the formation/disappearance of dust particles in the plasma can be maintained on a very large scale of discharge duration. The significance of discharge axial asymmetry to the dust particles behaviour in the plasma is revealed by the development of an asymmetric in shape void shifted towards the powered RF electrode. The key role of the reactive gas and its pulsed injection on each stage of the oscillating process of formation/disappearance of dust particles is disclosed by optical and electrical measurements. It is shown that the period of dusty plasma formation/disappearance is inversely related to the HMDSO injection time. Moreover, the impact of time injection over short period (5 s) is examined. It indicates the conflicting role played by the HMDSO on the reduction of dusty plasma during the reactive gas injection and the reappearance of particles in the plasma during the time off. The electronegative behavior of the plasma in the presence of negatively charged particles seems to explain the energetic modifications in the discharge. A frequency analysis of the floating potential reveals all these cyclic processes. Particularly, in the 10-200 Hz frequency range, the presence and the evolution of dust particles in the plasma over one generation can be observed.

  5. Effects of Rainfall Properties on Peak-Discharge Scaling Structure in a Mesoscale River Basin

    NASA Astrophysics Data System (ADS)

    Ayalew, T. B.; Krajewski, W. F.; Mantilla, R.

    2013-12-01

    A number of empirical studies have shown that peak-discharge quantiles exhibit scale invariance with respect to drainage area and can be described by the power law formula Q(A)=αAθ. However, its use for flood prediction purpose at the event scale requires understanding how multiple aspects of the rainfall-runoff process control both the intercept (α) and the exponent (θ). To this end, recent research has focused on understanding the physical basis for the observed scaling structure of peak-discharges that occur in a nested watershed following a runoff generating rainfall event. To date, only empirical studies over a small 21 km2 Goodwin Creek Experimental Watershed (GCEW) in northern Mississippi determined the event scale dependence of α and θ on excess rainfall properties. We expanded the analysis to the 32,700 km2 Iowa River basin in Iowa and examined the river basin response across multiple spatial scales. There are 41 streamflow gauging sites that monitor subcatchments with drainage area as small as 6.7 km2. The streamflow data is complemented by the Stage-IV radar rainfall product since 2002. Our results show that a scale-invariant peak flow scaling structure emerges when the rainfall event covers the entire river basin. Most importantly, we show that θ increases with increasing rainfall duration and its value ranges between the scaling exponent of the width function maxima (β=0.47) and unity. We also show that α increases with increasing rainfall intensity and is independent of the rainfall duration. Our results show that peak-discharges generated following snow melt also exhibit scale invariance with θ values closer to one. These results provide the early empirical evidence for the occurrence and property of scale invariant peak-discharges in a mesoscale river basin following single rainfall events.

  6. Discharge and Nitrogen Transfer Modelling in the Berze River: A HYPE Setup and Calibration

    NASA Astrophysics Data System (ADS)

    Veinbergs, Arturs; Lagzdins, Ainis; Jansons, Viesturs; Abramenko, Kaspars; Sudars, Ritvars

    2017-05-01

    This study is focused on water quality and quantity modelling in the Berze River basin located in the Zemgale region of Latvia. The contributing basin area of 872 km2 is furthermore divided into 15 sub-basins designated according to the characteristics of hydrological network and water sampling programme. The river basin of interest is a spatially complex system with agricultural land and forests as two predominant land use types. Complexity of the system reflects in the discharge intensity and diffuse pollution of nitrogen compounds into the water bodies of the river basin. The presence of urban area has an impact as the load from the existing wastewater treatment plants consist up to 76 % of the total nitrogen load in the Berze River basin. Representative data sets of land cover, agricultural field data base for crop distribution analysis, estimation of crop management, soil type map, digital elevation model, drainage conditions, network of water bodies and point sources were used for the modelling procedures. The semi-distributed hydro chemical model HYPE has a setup to simulate discharge and nitrogen transfer. In order to make the model more robust and appropriate for the current study the data sets previously stated were classified by unifying similar spatially located polygons. The data layers were overlaid and 53 hydrological response units (SLCs) were created. Agricultural land consists of 48 SLCs with the details of soils, drainage conditions, crop types, and land management practices. Manual calibration procedure was applied to improve the performance of discharge simulation. Simulated discharge values showed good agreement with the observed values with the Nash-Sutcliffe efficiency of 0.82 and bias of -6.6 %. Manual calibration of parameters related to nitrogen leakage simulation was applied to test the most sensitive parameters.

  7. Heterogeneous hyporheic zone dechlorination of a TCE groundwater plume discharging to an urban river reach.

    PubMed

    Freitas, Juliana G; Rivett, Michael O; Roche, Rachel S; Durrant Neé Cleverly, Megan; Walker, Caroline; Tellam, John H

    2015-02-01

    The typically elevated natural attenuation capacity of riverbed-hyporheic zones is expected to decrease chlorinated hydrocarbon (CHC) groundwater plume discharges to river receptors through dechlorination reactions. The aim of this study was to assess physico-chemical processes controlling field-scale variation in riverbed-hyporheic zone dechlorination of a TCE groundwater plume discharge to an urban river reach. The 50-m long pool-riffle-glide reach of the River Tame in Birmingham (UK) studied is a heterogeneous high energy river environment. The shallow riverbed was instrumented with a detailed network of multilevel samplers. Freeze coring revealed a geologically heterogeneous and poorly sorted riverbed. A chlorine number reduction approach provided a quantitative indicator of CHC dechlorination. Three sub-reaches of contrasting behaviour were identified. Greatest dechlorination occurred in the riffle sub-reach that was characterised by hyporheic zone flows, moderate sulphate concentrations and pH, anaerobic conditions, low iron, but elevated manganese concentrations with evidence of sulphate reduction. Transient hyporheic zone flows allowing input to varying riverbed depths of organic matter are anticipated to be a key control. The glide sub-reach displayed negligible dechlorination attributed to the predominant groundwater baseflow discharge condition, absence of hyporheic zone, transition to more oxic conditions and elevated sulphate concentrations expected to locally inhibit dechlorination. The tail-of-pool-riffle sub-reach exhibited patchy dechlorination that was attributed to sub-reach complexities including significant flow bypass of a low permeability, high organic matter, silty unit of high dechlorination potential. A process-based conceptual model of reach-scale dechlorination variability was developed. Key findings of practitioner relevance were: riverbed-hyporheic zone CHC dechlorination may provide only a partial, somewhat patchy barrier to CHC

  8. Influence of wind and river discharge on the hypoxia in a shallow bay

    NASA Astrophysics Data System (ADS)

    Xia, Meng; Jiang, Long

    2015-05-01

    Perdido Bay is a shallow bay with narrow inlets connecting with Gulf of Mexico. It is affected by severe hypoxia problem due to its narrow tidal range of around 0.4 m. An existing calibrated eutrophication model, as described in Xia et al. (J Coastal Res 719: 73-86, 2011a), was used to simulate the bottom hypoxia of Perdido Bay in response to the changing local wind and river discharge. In addition, the response of nutrient dynamics and algae distribution to these physical forces was also discussed, in order to understand the hypoxia dynamics. Compared to a no wind case, we found that southerly (onshore) and westerly favorable winds with speed of 3 m/s or less inhibited the nutrient and algae transport, while easterly favorable winds and northerly (offshore) winds favored nutrient and algae transport. Onshore and westerly winds were most effective at inducing significantly broader and thicker hypoxic/anoxic conditions. Increasing wind speed could limit the nutrient-rich freshwater to the upper bay. On the other hand, a 5-m/s southerly wind or above was sufficient to make vertical distribution of nutrients uniform, significantly reducing areal coverage of hypoxia/anoxia. We also discovered that increasing river discharge drove the nutrient-rich, high algae waters down to the bay mouth. Under a high-volume river discharge (100 m3/s, henceforth denoted as cms), the freshwater could reach the bottom in shallow areas (e.g., depth < 1 m), whereby the severity of anoxia and hypoxia was reduced, while increasing river discharge had little effect on the bottom hypoxia and nutrient variation in deepwater.

  9. Isotopic investigation of the discharge driven nitrogen dynamics in a mesoscale river catchment

    NASA Astrophysics Data System (ADS)

    Mueller, Christin; Zink, Matthias; Krieg, Ronald; Rode, Michael; Merz, Ralf; Knöller, Kay

    2016-04-01

    Nitrate in surface and groundwater has increased in the last decades due to landuse change, the application of different fertilizer for agricultural landuse and industrial dust in the atmospheric deposition. Increasing nitrate concentrations have a major impact on eutrophication, especially for coastal ecosystems. Therefore it is important to quantify potential nitrate sources and determine nitrate process dynamics with its drivers. The Bode River catchment (total size of 3200 m2) in the Harz Mountains in Germany was intensively investigated by a monitoring approach with 133 sampling points representing the same number of sub-catchments for a period of two years. The area is characterized by a strong anthropogenic gradient, with forest conservation areas in the mountain region, grassland, and intensively mixed farming in the lowlands. Consecutive discharge simulations by a mesoscale hydrological model (mhM) allow a quantitative analysis of nitrate fluxes for all observed tributaries. The investigation of nitrate isotopic signatures for characteristic landscape types allows the delineation of dominant NO3- sources: coniferous forests are characterized by recycled nitrified soil nitrogen; grassland is mainly impacted by organic fertilizer (manure) and nitrified soil-N; in agricultural land use areas nitrate predominantly derives from synthetic fertilizer application. Besides source delineation, the relationship between runoff and nitrate dynamics was analyzed for the entire Bode river catchment and, more detailed, for one major tributary with minor artificial reservoirs (Selke River). Thereby, it becomes apparent that nitrate isotopic variations increase with decreasing discharge. This effect might be due to a local, more intense impact of bacterial denitrification under low discharge conditions (higher residence time) in the anoxic soil zone, in the groundwater that discharges into the river and in the hyporheic zone. Generally, δ15N and δ18Oof nitrate decrease

  10. Effects of high salinity wastewater discharges on unionid mussels in the Allegheny River, Pennsylvania

    USGS Publications Warehouse

    Kathleen Patnode,; Hittle, Elizabeth A.; Robert Anderson,; Lora Zimmerman,; Fulton, John W.

    2015-01-01

    We examined the effect of high salinity wastewater (brine) from oil and natural gas drilling on freshwater mussels in the Allegheny River, Pennsylvania, during 2012. Mussel cages (N = 5 per site) were deployed at two sites upstream and four sites downstream of a brine treatment facility on the Allegheny River. Each cage contained 20 juvenile northern riffleshell mussels Epioblasma torulosa rangiana). Continuous specific conductance and temperature data were recorded by water quality probes deployed at each site. To measure the amount of mixing throughout the entire study area, specific conductance surveys were completed two times during low-flow conditions along transects from bank to bank that targeted upstream (reference) reaches, a municipal wastewater treatment plant discharge upstream of the brine-facility discharge, the brine facility, and downstream reaches. Specific conductance data indicated that high specific conductance water from the brine facility (4,000–12,000 µS/cm; mean 7,846) compared to the reference reach (103–188 µS/cm; mean 151) is carried along the left descending bank of the river and that dilution of the discharge via mixing does not occur until 0.5 mi (805 m) downstream. Juvenile northern riffleshell mussel survival was severely impaired within the high specific conductance zone (2 and 34% at and downstream of the brine facility, respectively) and at the municipal wastewater treatment plant (21%) compared to background (84%). We surveyed native mussels (family Unionidae) at 10 transects: 3 upstream, 3 within, and 4 downstream of the high specific conductance zone. Unionid mussel abundance and diversity were lower for all transects within and downstream of the high conductivity zone compared to upstream. The results of this study clearly demonstrate in situ toxicity to juvenile northern riffleshell mussels, a federally endangered species, and to the native unionid mussel assemblage located downstream of a brine discharge to the

  11. Reconnaissance investigations of the discharge and water quality of the Amazon River

    USGS Publications Warehouse

    Oltman, Roy Edwin

    1968-01-01

    Selected published estimates of the discharge of Amazon River in the vicinity of Obidos and the mouth are presented to show the great variance of available information. The most reasonable estimates prepared by those who measured some parameters of the flow were studied by Maurice Parde, who concluded that the mean annual discharge is 90,000 to 100,000 cms (cubic meters per second) or 3,200,000 to 3,500,000 cfs (cubic feet per second). A few published estimates of discharge at mouth of 110,000 cms (3,900,000 cfs) based on rainfall-runoff relationships developed for other humid regions of the world are available. Three measurements of discharge made at the Obidos narrows in 1963-64 by a joint Brazil-United States expedition at high, low, and medium river stage are referred to the datum used at the Obidos gage during the period of operation, 1928-46, and a relationship between stage and discharge prepared on the basis of the measurements and supplementary data and computations. Recovery of the original Obidos gage datum is verified by referring the 1963-64 concurrent river stages at Manaus, Obidos, and Taperinha to gage relation curves developed for Manaus-Obidos and Obidos-Taperinha for periods of concurrent operation, 1928-46 and 1931-46, respectively. The average discharge, based on the stage-discharge relation and record of river stage for the period 1928-46, is computed to be 5,500,000 cfs (157,000 cms) for the Obidos site. The greatest known flood at Obidos, that of June 1953, is computed to have been a flow of 12,500,000 cfs (350,000 cms) at stage of 7.6 meters (24.9 feet) in the main channel and an indeterminate amount of overflow which, under the best assumed overflow conditions, may have amounted to about 10 percent of the main channel flow. Overflow discharge at stage equivalent to mean annual discharge is judged to be an insignificant percentage of flow down the main channel. Miscellaneous data collected during the flow measurements show that the tidal

  12. Analysis for Elasticity of Rainfall - Discharge - Pollutant Loads considering Climate Change in Nakdong River Basin

    NASA Astrophysics Data System (ADS)

    Shon, T.; Kim, M.; Jang, Y.; Yi, J.; Shin, H.

    2012-12-01

    Climate change has been settled as pending issues to consider water resources and environment all over the world. However, scientific and quantitative assessment methods of climate change have never been standardized. When South Korea headed toward water deficiency nation, the study is not only required analysis of atmospheric or hydrologic factors, but also demanded analysis of correlation with water quality environment factors to gain management policies about climate change. Therefore, this study explored appropriate monthly rainfall-discharge elasticity in chosen 41 unit watersheds in Nakdong river which is one of the most important basin in Korea and applied monitored discharge data in 2004 to 2008 with monthly rainfall that estimated area rainfall . And each unit watershed drew elasticity between discharge and loads such as BOD, COD, SS, TN, and TP. Elasticity of monthly rainfall and discharge has estimated similarly value between total average and upstream, midstream and downstream average. And Elasticity of discharge and loads has estimated high value of all factors. Especially elasticity of discharge and SS loads is the highest value of all factors. Afterwards, this study will be continued to try different factors considerations in the near future and expected deepen research to overcome and improve limitation in this study.

  13. Preliminary stage-discharge relations for Tombigbee River at Aliceville lock and dam, near Pickensville, Alabama

    USGS Publications Warehouse

    Nelson, G.H.; Ming, C.O.

    1983-01-01

    The construction of Aliceville lock and dam and other related channel alterations, completed in 1979, has resulted in changes to the stage-discharge relations in the vicinity. The scarcity of current-meter measurements, coupled with backwater conditions, makes definition of a single stage-discharge relation impossible. However, limit curves can be defined that would encompass such a relation. Backwater is defined as water backed up or retarded in its course as compared with water flowing under normal or natural conditions. This results in a rise in stage above normal water level while the discharge remains unaffected. Backwater is usually caused by temporary obstruction(s) to flow downstream. Backwater at Aliceville Dam results from a variety of river conditions. Some of these conditions are large tributary inflow, return of flood plain flows to the main channel during recessions, and operations at Gainesville Dam during low flows. The discharges obtained from 26 current-meter measurements, along with computed discharges through the dam, are plotted versus stage. The plot illustrates, by the scatter of data points, the variations in backwater. Curves are drawn to envelope the extreme plot patterns showing possible ranges of several feet in stage for any given discharge. The upper end of the curves were extrapolated based on the results of a step-backwater analysis.

  14. Forward to the Future: Estimating River Discharge with McFLI

    NASA Astrophysics Data System (ADS)

    Gleason, C. J.; Durand, M. T.; Garambois, P. A.

    2016-12-01

    The global surface water budget is still poorly understood, and improving our understanding of freshwater budgets requires coordination between in situ observations, models, and remote sensing. The upcoming launch of the NASA/CNES Surface Water and Ocean Topography (SWOT) satellite has generated considerable excitement as a new tool enabling hydrologists to tackle some of the most pressing questions facing their discipline. One question in particular which SWOT seems well suited to answer is river discharge (flow rate) estimation in ungauged basins: SWOT's anticipated measurements of river surface height and area have ushered in a new technique in hydrology- what we are here calling Mass conserved Flow Law Inversions, or McFLI. McFLI algorithms leverage classic hydraulic flow expressions (e.g. Manning's Equation, hydraulic geometry) within mass conserved river reaches to construct a simplified but still underconstrained system of equations to be solved for an unknown discharge. Most existing McFLI techniques have been designed to take advantage of SWOT's measurements and Manning's Equation: SWOT will observe changes in cross sectional area and river surface slope over time, so the McFLI need only solve for baseflow area and Manning's roughness coefficient. Recently published preliminary results have indicated that McFLI can be a viable tool in a global hydrologist's toolbox (discharge errors less than 30% as compared to gauges are possible in most cases). Therefore, we here outline the progress to date for McFLI techniques, and highlight three key areas for future development: 1) Maximize the accuracy and robustness of McFLI by incorporating ancillary data from satellites, models, and in situ observations. 2) Develop new McFLI techniques using novel or underutilized flow laws. 3) Systematically test McFLI to define different inversion classes of rivers with well-defined error budgets based on geography and available data for use in gauged and ungauged basins alike.

  15. Hydrologic control of carbon cycling and aged carbon discharge in the Congo River basin

    NASA Astrophysics Data System (ADS)

    Schefuß, Enno; Eglinton, Timothy I.; Spencer-Jones, Charlotte L.; Rullkötter, Jürgen; de Pol-Holz, Ricardo; Talbot, Helen M.; Grootes, Pieter M.; Schneider, Ralph R.

    2016-09-01

    The age of organic material discharged by rivers provides information about its sources and carbon cycling processes within watersheds. Although elevated ages in fluvially transported organic matter are usually explained by erosion of soils and sedimentary deposits, it is commonly assumed that mainly young organic material is discharged from flat tropical watersheds due to their extensive plant cover and rapid carbon turnover. Here we present compound-specific radiocarbon data of terrigenous organic fractions from a sedimentary archive offshore the Congo River, in conjunction with molecular markers for methane-producing land cover reflecting wetland extent. We find that the Congo River has been discharging aged organic matter for several thousand years, with apparently increasing ages from the mid- to the Late Holocene. This suggests that aged organic matter in modern samples is concealed by radiocarbon from atmospheric nuclear weapons testing. By comparison to indicators for past rainfall changes we detect a systematic control of organic matter sequestration and release by continental hydrology, mediating temporary carbon storage in wetlands. As aridification also leads to exposure and rapid remineralization of large amounts of previously stored labile organic matter, we infer that this process may cause a profound direct climate feedback that is at present underestimated in carbon cycle assessments.

  16. Passive acoustic monitoring of bed load discharge in a large gravel bed river

    NASA Astrophysics Data System (ADS)

    Geay, T.; Belleudy, P.; Gervaise, C.; Habersack, H.; Aigner, J.; Kreisler, A.; Seitz, H.; Laronne, J. B.

    2017-02-01

    Surrogate technologies to monitor bed load discharge have been developed to supplement and ultimately take over traditional direct methods. Our research deals with passive acoustic monitoring of bed load flux using a hydrophone continuously deployed near a river bed. This passive acoustic technology senses any acoustic waves propagated in the river environment and particularly the sound due to interparticle collisions emitted during bed load movement. A data set has been acquired in the large Alpine gravel-bedded Drau River. Analysis of the short-term frequency response of acoustic signals allows us to determine the origin of recorded noises and to consider their frequency variations. Results are compared with ancillary field data of water depth and bed load transport inferred from the signals of a geophone array. Hydrophone and geophone signals are well correlated. Thanks to the large network of deployed geophones, analysis of the spatial resolution of hydrophone measurements shows that the sensor is sensitive to bed load motion not only locally but over distances of 5-10 m (10-20% of river width). Our results are promising in terms of the potential use of hydrophones for monitoring bed load transport in large gravel bed rivers: acoustic signals represent a large river bed area, rather than being local; hydrophones can be installed in large floods; they can be deployed at a low cost and provide continuous monitoring at high temporal resolution.

  17. Steroid estrogens profiles along river stretches arising from sewage treatment works discharges.

    PubMed

    Williams, Richard J; Johnson, Andrew C; Smith, Jennifer J L; Kanda, Rakesh

    2003-05-01

    Concentrations of estradiol, estrone, and ethinylestradiol were measured in the water column (daily for 28 or 14 days) and in the bed sediment (weekly over the same period) of the River Nene and the River Lea, U.K., upstream and downstream of sewage treatment works (STW). The concentrations of the three steroids in the STW effluents were also measured. Estrone was detected at the highest concentration and in almost all samples from the three STW effluents, concentrations ranging from <0.4 to 12.2 ng/L. Estradiol was also detected frequently (<0.4-4.3 ng/L), but ethinylestradiol was detected infrequently (<0.4-3.4 ng/L). Positive detections were only found for estrone in the sediment, and these seemed to be unrelated to the water column concentrations. Levels of estrone were clearly raised above background levels in the rivers as a result of the STW discharges. Levels of estradiol and ethinylestradiol were too close to their detection limits to assess the STW impact. River water estrone concentration declined downstream at a rate that was in excess of that due to dilution. The most likely cause of this decline is a combination of sorption and biodegradation equivalent to a first-order decay half-life of 2.5 days for the River Nene and 0.5 days for the River Lea.

  18. Correlative estimates of discharge for three sites in the upper Lewis River Basin, Washington

    USGS Publications Warehouse

    Bodhaine, G.L.

    1957-01-01

    In response to increased interest in the power possibilities of tributary streams in the headwater of Lewis River stream-gaging stations were reestablished in 1955 at three sites in the upper Lewis River basin, Washington. The one year of recent record now available and the four years of record obtained during water years 1928-31 provide a reasonable basis for estimates of monthly discharge during the intervening years. In view of the current interest in the discharge of these streams estimates of monthly discharge have been made in the Tacoma district office of the Surface Water Branch of the U.S. Geological Survey. These estimates and a description of the method of correlation are attached. The three stations and the period covered by the correlative estimates are as follows: Big Creek below Skookum Meadow near Trout Lake, Washington: Oct. 1931 to Sept. 1955 Meadow Creek below Lone Butte Meadow near Trout Lake, Washington: Oct. to Dec. 1928; Oct. 1931 to Sept. 1955 Rush Creek above falls, near Cougar, Wash.: Oct. to Dec. 1928; Dec. 1931 to Sept. 1955 Published records for water years 1928-31 and 1956 are included in the tabulation to provide discharge for the full period Oct. 1927 to Sept. 1956.

  19. Reconstruction of North American drainage basins and river discharge since the Last Glacial Maximum

    NASA Astrophysics Data System (ADS)

    Wickert, Andrew D.

    2016-11-01

    Over the last glacial cycle, ice sheets and the resultant glacial isostatic adjustment (GIA) rearranged river systems. As these riverine threads that tied the ice sheets to the sea were stretched, severed, and restructured, they also shrank and swelled with the pulse of meltwater inputs and time-varying drainage basin areas, and sometimes delivered enough meltwater to the oceans in the right places to influence global climate. Here I present a general method to compute past river flow paths, drainage basin geometries, and river discharges, by combining models of past ice sheets, glacial isostatic adjustment, and climate. The result is a time series of synthetic paleohydrographs and drainage basin maps from the Last Glacial Maximum to present for nine major drainage basins - the Mississippi, Rio Grande, Colorado, Columbia, Mackenzie, Hudson Bay, Saint Lawrence, Hudson, and Susquehanna/Chesapeake Bay. These are based on five published reconstructions of the North American ice sheets. I compare these maps with drainage reconstructions and discharge histories based on a review of observational evidence, including river deposits and terraces, isotopic records, mineral provenance markers, glacial moraine histories, and evidence of ice stream and tunnel valley flow directions. The sharp boundaries of the reconstructed past drainage basins complement the flexurally smoothed GIA signal that is more often used to validate ice-sheet reconstructions, and provide a complementary framework to reduce nonuniqueness in model reconstructions of the North American ice-sheet complex.

  20. Drill hole data for coal beds in the Powder River Basin, Montana and Wyoming

    USGS Publications Warehouse

    Haacke, Jon E.; Scott, David C.

    2013-01-01

    This report by the U.S. Geological Survey (USGS) of the Powder River Basin (PRB) of Montana and Wyoming is part of the U.S. Coal Resources and Reserves Assessment Project. Essential to that project was the creation of a comprehensive drill hole database that was used for coal bed correlation and for coal resource and reserve assessments in the PRB. This drill hole database was assembled using data from the USGS National Coal Resources Data System, several other Federal and State agencies, and selected mining companies. Additionally, USGS personnel manually entered lithologic picks into the database from geophysical logs of coalbed methane, oil, and gas wells. Of the 29,928 drill holes processed, records of 21,393 are in the public domain and are included in this report. The database contains location information, lithology, and coal bed names for each drill hole.

  1. Seismic amplitude anomalies associated with thick First Leo sandstone lenses, eastern Powder River basin, Wyoming.

    USGS Publications Warehouse

    Balch, A.H.; Lee, M.W.; Miller, J.J.; Ryder, R.T.

    1981-01-01

    Several new discoveries of oil production in the Leo sandstone, an economic unit in the Pennsylvanian middle member of the Minnelusa formation, eastern Powder River basin, Wyoming-Nebraska-South Dakota, have renewed exploration interest in this area. Vertical seismic profiles (VSP) and model studies suggested that a measurable seismic amplitude anomaly is frequently associated with the thick First Leo sandstone lenses. To test this concept, a surface reflection seismic profile was run between two wells about 12 miles apart. The First Leo was present and productive in one well and thin and barren in the other. The surface profile shows the predicted amplitude anomaly at the well where a thick lens is known to exist. Two other First Leo amplitude anomalies also appear on the surface seismic profile between the two wells, which may indicate the presence of additional lenses.-Authors

  2. Coal aquifer contribution to streams in the Powder River Basin, Montana

    NASA Astrophysics Data System (ADS)

    Meredith, Elizabeth Brinck

    2016-06-01

    Groundwater contributions to streams can be reduced by groundwater withdrawal associated with coalbed methane and coal mine production. Quantifying the groundwater contribution to streams aids the assessment of potential impacts to in-stream flow and provides information necessary for energy producers to use coproduced water for beneficial purposes, rather than treating it as a waste product. Stream flow, field parameters, common ions, and isotopes of carbon and strontium were measured on Otter Creek and the Powder River in southeastern Montana. Direct streamflow measurements were ineffective because of the magnitude and nature of coalbed contribution. The coal groundwater contribution did not exceed the geochemical detection threshold on two nearby streams. Geochemical models based on isotopic data proved to be the most effective analytical method, resulting in baseflow measurements from coal aquifers of 28-275 l s-1.

  3. The influence of extreme river discharge conditions on the quality of suspended particulate matter in Rivers Meuse and Rhine (The Netherlands).

    PubMed

    Hamers, Timo; Kamstra, Jorke H; van Gils, Jos; Kotte, Marcel C; van Hattum, Albertus G M

    2015-11-01

    As a consequence of climate change, increased precipitation in winter and longer periods of decreased precipitation in summer are expected to cause more frequent episodes of very high or very low river discharge in the Netherlands. To study the impact of such extreme river discharge conditions on water quality, toxicity profiles and pollutant profiles were determined of suspended particulate matter (SPM) collected from Rivers Meuse and Rhine. Archived (1993-2003) and fresh (2009-2011) SPM samples were selected from the Dutch annual monitoring program of the national water bodies (MWTL), representing episodes with river discharge conditions ranging from very low to regular to very high. SPM extracts were tested in a battery of in vitro bioassays for their potency to interact with the androgen receptor (AR), the estrogen receptor (ER), the arylhydrocarbon receptor (AhR), and the thyroid hormone transporter protein transthyretin (TTR). SPM extracts were further tested for their mutagenic potency (Ames assay) and their potency to inhibit bacterial respiration (Vibrio fischeri bioluminescence assay). Target-analyzed pollutant concentrations of the SPM samples and additional sample information were retrieved from a public database of MWTL results. In vitro toxicity profiles and pollutant profiles were analyzed in relation to discharge conditions and in relation to each other using correlation analysis and multivariate statistics. Compared to regular discharge conditions, composition of SPM during very high River Meuse and Rhine discharges shifted to more coarse, sandy, organic carbon (OC) poor particles. On the contrary, very low discharge led to a shift to more fine, OC rich material, probably dominated by algae. This shift was most evident in River Meuse, which is characterized by almost stagnant water conditions during episodes of drought. During such episodes, SPM extracts from River Meuse demonstrated increased potencies to inhibit bacterial respiration and to

  4. Discharge ratings for control structures at McHenry Dam on the Fox River, Illinois

    USGS Publications Warehouse

    Fisk, G.G.

    1988-01-01

    Twenty-three measurement of discharge were used to determine discharge ratings for the five adjustable sluice gates, spillway and fish ladder at McHenry Dam on the Fox River in Illinois. Discharge ratings were determined for free weir, free orifice, and submerged orifice flow regimes. Hydraulic conditions that identify flow regimes at McHenry Dam are defined by ratios between headwater depth (h1), tailwater depth (h3), and gate opening (hg). Flow under the sluice gates is identified as weir flow when the ratio of gate opening to headwater depth is greater than 0.73, and as orifice flow when hg/H1 is less than 0.73. Free orifice flow occurs when the ratio of tailwater depth to gate opening is less than 1.3, and submerged orifice flow occurs when h3/hg is greater than 1.3. Flow under the sluice gates is identified as free weir flow when the ratio of tailwater depth to headwater depth is less than 0.75, and as submerged weir flow when h3/h1 is greater than 0.75. Flow over the spillway is identified as free weir flow when the ratio of tailwater depth to headwater depth is less than 0.60, and as submerged weir flow when h3/h1 is greater than 0.60. Discharge coefficients to be used in equations to compute discharge for various hydraulic conditions were determined. Four discharge measurement, ranging from 169 to 2990 cu ft/sec, were used to define discharge coefficients that varies from 2.61 to 3.14 for free weir flow over the spillway. Nineteen discharge measurements, ranging from 180 to 4050 cu ft/sec, were used to define discharge coefficients for free weir, free orifice, and submerged orifice flow under the sluice gates. The average value of the discharge coefficient for free weir flow under the sluice gates is 3.17. Discharge coefficients for free orifice flow varied from 0.48 to 0.66 and the discharge coefficients for submerged orifice flow from the two measurements were 0.59 and 0.67. (Author 's abstract)

  5. A model study of the effects of river discharges and winds on hypoxia in summer in the Pearl River Estuary.

    PubMed

    Wei, Xing; Zhan, Haigang; Ni, Peitong; Cai, Shuqun

    2016-12-15

    The deterioration of dissolved oxygen conditions in the Pearl River Estuary (PRE) in summer has recently attracted considerable-scientific and political-attention. This paper documents the development, calibration, and verification of a coupled three-dimensional hydrodynamic and water quality model for the PRE. A comparison of the model's performance against field observations indicated that the model is capable of reproducing key hydrodynamic and water quality characteristics of the estuary within an acceptable range of accuracy. Furthermore, a scenario analysis showed that the extent of the hypoxic zone responds differently to changes in the river discharge at different inlets. Moreover, the hypoxic zone also changes in response to variations in the southwest wind in summer; specifically, a larger hypoxic zone develops as southwest winds blow in a more southward direction. However, the hypoxic conditions are much more sensitive to changes in the wind speed than changes in the wind direction. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Sediment discharge of the rivers of Catalonia, NE Spain, and the influence of human impacts

    NASA Astrophysics Data System (ADS)

    Liquete, Camino; Canals, Miquel; Ludwig, Wolfgang; Arnau, Pedro

    2009-03-01

    SummaryThe environmental and anthropogenic factors controlling sediment delivery to the sea are numerous, intricate and usually difficult to quantify. Mediterranean watersheds are historically amongst the most heavily impacted by human activities in the world. This study analyzes some of these factors for nine river systems from Catalonia, NE Spain, that open into the Northwestern Mediterranean Sea, and discusses the results obtained from sediment yield models and sediment concentration data series. General models indicate that the natural suspended sediment yield by individual Catalan rivers ranged within a fork from 94 to 621 t km -2 yr -1. Such a sediment yield would be noticeably reduced (moving the fork to 7-148 t km -2 yr -1) because of lithological factors and direct anthropogenic and, possibly, climatic impacts. Damming, water extraction and urbanization appear as the most important direct anthropogenic impacts in Catalonia. Water discharge and sediment concentration measurements by basin authorities provide much lower sediment yield estimations, from 0.4 to 19.8 t km -2 yr -1, which is probably due to the lack of measured sediment loads during flood events, as it is the case in many other Mediterranean rivers. The Catalan watersheds have some of the smallest runoff values amongst Mediterranean rivers. Of the nine river systems studied, water discharge tends to decrease in two and to increase in one. The other six river systems do not show any clear tendency. Related to climatic parameters, temperature raised in all the watersheds between 1961 and 1990, while precipitation did not show significant trends.

  7. Multi-parameter Analysis and Visualization of Groundwater Quality during High River Discharge Events

    NASA Astrophysics Data System (ADS)

    Page, R. M.; Huggenberger, P.; Lischeid, G.

    2010-12-01

    The filter capacity of alluvial aquifers enables many groundwater extraction wells near rivers to provide high-quality drinking water during average flow and surface water quality conditions. However, during high river discharge events, the bacterial load of the groundwater is increased and the extracted water is no longer safe for the production of drinking water without treatment. Optimal management of production wells requires well-founded knowledge of the river - groundwater interaction and transport of microorganisms over this interface. Due to the spatial and temporal variability of river - groundwater interaction, monitoring individual parameters does not always correctly identify the actual potential risk of contamination of drinking water. Identifying situations where the quality is insufficient can be difficult in systems that are influenced by many factors including natural and artificial recharge, as well as extraction. As high-resolution sampling for waterborne pathogens during flood events is cost and time intensive, proxies are usually used in addition to short-term microbial monitoring studies. The resulting datasets are multi-dimensional and have variable temporal resolutions. For these reasons, it is necessary to apply procedures where multivariate datasets can be considered simultaneously and inherent patterns visualized. These patterns are important for determining the governing processes and can be used to assess the actual potential risk of contamination due to infiltrating surface water. In this study, a multi-parameter dataset, including specific conductivity and faecal indicators (Escherichia coli, enterococci and aerobic mesophilic germs), was analyzed using a combination of the Self-Organizing Map (SOM) and Sammon's mapping techniques. The SOM analysis allowed to differentiate between the effects of groundwater extraction and fluctuations of the river table on groundwater levels, electric conductivity and temperature in the well field

  8. Powder River Basin Coalbed Methane Development and Produced Water Management Study

    SciTech Connect

    Advanced Resources International

    2002-11-30

    Coalbed methane resources throughout the entire Powder River Basin were reviewed in this analysis. The study was conducted at the township level, and as with all assessments conducted at such a broad level, readers must recognize and understand the limitations and appropriate use of the results. Raw and derived data provided in this report will not generally apply to any specific location. The coal geology in the basin is complex, which makes correlation with individual seams difficult at times. Although more than 12,000 wells have been drilled to date, large areas of the Powder River Basin remain relatively undeveloped. The lack of data obviously introduces uncertainty and increases variability. Proxies and analogs were used in the analysis out of necessity, though these were always based on sound reasoning. Future development in the basin will make new data and interpretations available, which will lead to a more complete description of the coals and their fluid flow properties, and refined estimates of natural gas and water production rates and cumulative recoveries. Throughout the course of the study, critical data assumptions and relationships regarding gas content, methane adsorption isotherms, and reservoir pressure were the topics of much discussion with reviewers. A summary of these discussion topics is provided as an appendix. Water influx was not modeled although it is acknowledged that this phenomenon may occur in some settings. As with any resource assessment, technical and economic results are the product of the assumptions and methodology used. In this study, key assumptions as well as cost and price data, and economic parameters are presented to fully inform readers. Note that many quantities shown in various tables have been subject to rounding; therefore, aggregation of basic and intermediate quantities may differ from the values shown.

  9. Hydrologic properties of coal-beds in the Powder River Basin, Montana. II. Aquifer test analysis

    USGS Publications Warehouse

    Weeks, E.P.

    2005-01-01

    A multiple well aquifer test to determine anisotropic transmissivity was conducted on a coal-bed in the Powder River Basin, southeastern Montana, as part of a multidisciplinary investigation to determine hydrologic conditions of coal-beds in the area. For the test, three wells were drilled equidistant from and at different angles to a production well tapping the Flowers-Goodale coal seam, a 7.6-m thick seam confined at a depth of about 110 m. The test was conducted by air-lift pumping for 9 h, and water levels were monitored in the three observation wells using pressure transducers. Drawdown data collected early in the test were affected by interporosity flow between the coal fracture network and the matrix, but later data were suitable to determine aquifer anisotropy, as the slopes of the late-time semilog time-drawdown curves are nearly identical, and the zero-drawdown intercepts are different. The maximum transmissivity, trending N87??E, is 14.9 m2/d, and the minimum transmissivity 6.8 m2/d, giving an anisotropy ratio of 2.2:1. Combined specific storage of the fractures and matrix is 2??10 -5/m, and of the fracture network alone 5??10-6/m. The principal direction of the anisotropy tensor is not aligned with the face cleats, but instead is aligned with another fracture set and with dominant east-west tectonic compression. Results of the test indicate that the Flowers-Goodale coal-bed is more permeable than many coals in the Powder River Basin, but the anisotropy ratio and specific storage are similar to those found for other coal-beds in the basin.

  10. Groundwater chemistry near an impoundment for produced water, Powder River Basin, Wyoming, USA

    USGS Publications Warehouse

    Healy, R.W.; Bartos, T.T.; Rice, C.A.; McKinley, M.P.; Smith, B.D.

    2011-01-01

    The Powder River Basin is one of the largest producers of coal-bed natural gas (CBNG) in the United States. An important environmental concern in the Basin is the fate of the large amounts of groundwater extracted during CBNG production. Most of this produced water is disposed of in unlined surface impoundments. A 6-year study of groundwater flow and water chemistry at one impoundment, Skewed Reservoir, has produced the most detailed data set for any impoundment in the Basin. Data were collected from a network of 21 observation wells and three suction lysimeters. A groundwater mound formed atop bedrock within initially unsaturated, unconsolidated deposits underlying the reservoir. Heterogeneity in physical and chemical properties of sediments resulted in complex groundwater flow paths and highly variable groundwater chemistry. Sulfate, bicarbonate, sodium, and magnesium were the dominant ions in all areas, but substantial variability existed in relative concentrations; pH varied from less than 3 to more than 9, and total dissolved solids concentrations ranged from less than 5000 to greater than 100,000. mg/L. Selenium was a useful tracer of reservoir water; selenium concentrations exceeded 300 ??g/L in samples obtained from 18 of the 24 sampling points. Groundwater travel time from the reservoir to a nearby alluvial aquifer (a linear distance of 177. m) was calculated at 474. days on the basis of selenium concentrations. The produced water is not the primary source of solutes in the groundwater. Naturally occurring salts and minerals within the unsaturated zone, dissolved and mobilized by infiltrating impoundment water, account for most of the solute mass in groundwater. Gypsum dissolution, cation-exchange, and pyrite oxidation appear to be important reactions. The complex geochemistry and groundwater flow paths at the study site underscore the difficulty in assessing effects of surface impoundments on water resources within the Powder River Basin. ?? 2011.

  11. Viability of underground coal gasification in the 'deep coals' of the Powder River Basin, Wyoming

    SciTech Connect

    2007-06-15

    The objective of this work is to evaluate the PRB coal geology, hydrology, infrastructure, environmental and permitting requirements and to analyze the possible UCG projects which could be developed in the PRB. Project economics on the possible UCG configurations are presented to evaluate the viability of UCG. There are an estimated 510 billion tons of sub-bituminous coal in the Powder River Basin (PRB) of Wyoming. These coals are found in extremely thick seams that are up to 200 feet thick. The total deep coal resource in the PRB has a contained energy content in excess of twenty times the total world energy consumption in 2002. However, only approximately five percent of the coal resource is at depths less than 500 feet and of adequate thickness to be extracted by open pit mining. The balance is at depths between 500 and 2,000 feet below the surface. These are the PRB 'deep coals' evaluated for UCG in this report. The coal deposits in the Powder River Basin of Wyoming are thick, laterally continuous, and nearly flat lying. These deposits are ideal for development by Underground Coal Gasification. The thick deep coal seams of the PRB can be harvested using UCG and be protective of groundwater, air resources, and with minimum subsidence. Protection of these environmental values requires correct site selection, site characterization, impact definition, and impact mitigation. The operating 'lessons learned' of previous UCG operations, especially the 'Clean Cavity' concepts developed at Rocky Mountain 1, should be incorporated into the future UCG operations. UCG can be conducted in the PRB with acceptable environmental consequences. The report gives the recommended development components for UCG commercialization. 97 refs., 31 figs., 57 tabs., 1 app.

  12. Groundwater chemistry near an impoundment for produced water, Powder River Basin, Wyoming, USA

    NASA Astrophysics Data System (ADS)

    Healy, Richard W.; Bartos, Timothy T.; Rice, Cynthia A.; McKinley, Michael P.; Smith, Bruce D.

    2011-06-01

    SummaryThe Powder River Basin is one of the largest producers of coal-bed natural gas (CBNG) in the United States. An important environmental concern in the Basin is the fate of the large amounts of groundwater extracted during CBNG production. Most of this produced water is disposed of in unlined surface impoundments. A 6-year study of groundwater flow and water chemistry at one impoundment, Skewed Reservoir, has produced the most detailed data set for any impoundment in the Basin. Data were collected from a network of 21 observation wells and three suction lysimeters. A groundwater mound formed atop bedrock within initially unsaturated, unconsolidated deposits underlying the reservoir. Heterogeneity in physical and chemical properties of sediments resulted in complex groundwater flow paths and highly variable groundwater chemistry. Sulfate, bicarbonate, sodium, and magnesium were the dominant ions in all areas, but substantial variability existed in relative concentrations; pH varied from less than 3 to more than 9, and total dissolved solids concentrations ranged from less than 5000 to greater than 100,000 mg/L. Selenium was a useful tracer of reservoir water; selenium concentrations exceeded 300 μg/L in samples obtained from 18 of the 24 sampling points. Groundwater travel time from the reservoir to a nearby alluvial aquifer (a linear distance of 177 m) was calculated at 474 days on the basis of selenium concentrations. The produced water is not the primary source of solutes in the groundwater. Naturally occurring salts and minerals within the unsaturated zone, dissolved and mobilized by infiltrating impoundment water, account for most of the solute mass in groundwater. Gypsum dissolution, cation-exchange, and pyrite oxidation appear to be important reactions. The complex geochemistry and groundwater flow paths at the study site underscore the difficulty in assessing effects of surface impoundments on water resources within the Powder River Basin.

  13. Effects of river discharge and high-tide stage on salinity intrusion in the Weeki Wachee, Crystal, and Withlacoochee River estuaries, southwest Florida

    USGS Publications Warehouse

    Yobbi, D.K.; Knochenmus, L.A.

    1989-01-01

    The Weeki Wachee, Crystal, and Withlacoochee Rivers are coastal streams flowing into the Gulf of Mexico that may be affected by either future surface water or groundwater withdrawals. Reduction of river discharge will affect the upstream extent of saltwater intrusion in the rivers; however, under certain reduced low-flow discharges, the estimated change in upstream extent of saltwater intrusion is on the order of several tenths of a mile and frequently is within the range of predicted error. Data on flow, tides, and salinity describe the physical characteristics of the Weeki Wachee, Crystal, and Withlacoochee River systems. Vertical and longitudinal salinity profiles indicate that salinity of the rivers increases downstream and varies substantially at any given location. The Weeki Wachee River system is the best mixed of the three. The Crystal River system exhibited the next best mixed system, and the Withlacoochee River system exhibited the most variation in its salinity regime. The daily maximum upstream extent of salinity intrusion is described by multiple linear-regression analysis based on daily mean streamflow of each river and high-tide stage of the gulf. The equations are used to show the effects of discharge on the daily maximum upstream extent of salinity intrusion in the rivers. (USGS)

  14. User's guide for RIV2; a package for routing and accounting of river discharge for a modular, three-dimensional, finite-difference, ground- water flow model

    USGS Publications Warehouse

    Miller, Roger S.

    1988-01-01

    RIV2 is a package for the U.S. Geological Survey 's modular, three-dimensional, finite-difference, groundwater flow model developed by M. G. McDonald and A. W. Harbaugh that simulates river-discharge routing. RIV2 replaces RIVI, the original river package used in the model. RIV2 preserves the basic logic of RIV1, but better represents river-discharge routing. The main features of RIV2 are (1) The river system is divided into reaches and simulated river discharge is routed from one node to the next. (2) Inflow (river discharge) entering the upstream end of a reach can be specified. (3) More than one river can be represented at one node and rivers can cross, as when representing a siphon. (4) The quantity of leakage to or from the aquifer at a given node is proportional to the hydraulic-head difference between that specified for the river and that calculated for the aquifer. Also, the quantity of leakage to the aquifer at any node can be limited by the user and, within this limit, the maximum leakage to the aquifer is the discharge available in the river. This feature allows for the simulation of intermittent rivers and drains that have no discharge routed to their upstream reaches. (5) An accounting of river discharge is maintained. Neither stage-discharge relations nor storage in the river or river banks is simulated. (USGS)

  15. NOM degradation during river infiltration: effects of the climate variables temperature and discharge.

    PubMed

    Diem, Samuel; Rudolf von Rohr, Matthias; Hering, Janet G; Kohler, Hans-Peter E; Schirmer, Mario; von Gunten, Urs

    2013-11-01

    Most peri-alpine shallow aquifers fed by rivers are oxic and the drinking water derived by riverbank filtration is generally of excellent quality. However, observations during past heat waves suggest that water quality may be affected by climate change due to effects on redox processes such as aerobic respiration, denitrification, reductive dissolution of manganese(III/IV)- and iron(III)(hydr)oxides that occur during river infiltration. To assess the dependence of these redox processes on the climate-related variables temperature and discharge, we performed periodic and targeted (summer and winter) field sampling campaigns at the Thur River, Switzerland, and laboratory column experiments simulating the field conditions. Typical summer and winter field conditions could be successfully simulated by the column experiments. Dissolved organic matter (DOM) was found not to be a major electron donor for aerobic respiration in summer and the DOM consumption did not reveal a significant correlation with temperature and discharge. It is hypothesized that under summer conditions, organic matter associated with the aquifer material (particulate organic matter, POM) is responsible for most of the consumption of dissolved oxygen (DO), which was the most important electron acceptor in both the field and the column system. For typical summer conditions at temperatures >20 °C, complete depletion of DO was observed in the column system and in a piezometer located only a few metres from the river. Both in the field system and the column experiments, nitrate acted as a redox buffer preventing the release of manganese(II) and iron(II). For periodic field observations over five years, DO consumption showed a pronounced temperature dependence (correlation coefficient r = 0.74) and therefore a seasonal pattern, which seemed to be mostly explained by the temperature dependence of the calculated POM consumption (r = 0.7). The river discharge was found to be highly and positively correlated

  16. Tracking groundwater discharge to a large river using tracers and geophysics.

    PubMed

    Harrington, Glenn A; Gardner, W Payton; Munday, Tim J

    2014-01-01

    Few studies have investigated large reaches of rivers in which multiple sources of groundwater are responsible for maintaining baseflow. This paper builds upon previous work undertaken along the Fitzroy River, one of the largest perennial river systems in north-western Australia. Synoptic regional-scale sampling of both river water and groundwater for a suite of environmental tracers ((4) He, (87) Sr/(86) Sr, (222) Rn and major ions), and subsequent modeling of tracer behavior in the river, has enabled definition and quantification of groundwater input from at least three different sources. We show unambiguous evidence of both shallow "local" groundwater, possibly recharged to alluvial aquifers beneath the adjacent floodplain during recent high-flow events, and old "regional" groundwater introduced via artesian flow from deep confined aquifers. We also invoke hyporheic exchange and either bank return flow or parafluvial flow to account for background (222) Rn activities and anomalous chloride trends along river reaches where there is no evidence of the local or regional groundwater inputs. Vertical conductivity sections acquired through an airborne electromagnetic (AEM) survey provide insights to the architecture of the aquifers associated with these sources and general groundwater quality characteristics. These data indicate fresh groundwater from about 300 m below ground preferentially discharging to the river, at locations consistent with those inferred from tracer data. The results demonstrate how sampling rivers for multiple environmental tracers of different types-including stable and radioactive isotopes, dissolved gases and major ions-can significantly improve conceptualization of groundwater-surface water interaction processes, particularly when coupled with geophysical techniques in complex hydrogeological settings. © 2013, National Ground Water Association.

  17. Measuring the Discharge of River Flood Using Witnesses Movies Found on the Internet

    NASA Astrophysics Data System (ADS)

    Hauet, A.; Le Coz, J.; Le Boursicaud, R.; Pénard, L.

    2014-12-01

    The knowledge of the discharge of river during extreme flood is of prime importance for the scientific and the research community. Unfortunately, measuring discharge using conventional methods is impossible because the high velocities and the floating debris endanger the operators and the equipment. The typical time-scale for gauging does not match up to the time scale of the dynamic of extreme flood. Finally, floods are mesoscale events that affect generally several watersheds at the same time, and gauging teams do not have the capabilities for covering the whole region of interest. Recently, non intrusive method for measuring discharge have been developed and tested in flood conditions. Doppler surface velocity radar and Large Scale Particle Image Velocimetry (LSPIV) showed their efficiency for measuring discharge during extreme events, but those methods need to be deployed by operators and the problems of time-scale and space-scale covering aforementioned are not solved. In this study, authors present how flood discharge measurement can benefits from the huge development, the last 10 years, of internet and of the on-line sharing of files. Floods are impressive phenomena, and hundreds of witnesses movies can be found on the internet after every important event. The different steps in order to apply LSPIV analysis to witness movie are detailed: (i) selection of the video of interest; (ii) contact with the author of the video; (iii) preparing the video for the LSPIV analysis : stabilization of the images, field campaigns; (iv) LSPIV analysis, providing surface velocity field; and (v)discharge computation. A case study on the major flash flood of 18 June 2013 of the Gave River at Cauterets, French Pyrennees, is presented. Results show that witnesses movies can bring useful information and allow estimating discharges values. Capabilities and limitations of LSPIV applied to witnesses movies are detailed. Finally, the paper presents an approach conducted within the

  18. Sources of particulate organic matter discharged by the Lena River using lignin phenols

    NASA Astrophysics Data System (ADS)

    Winterfeld, M.; Trojahn, S.; Hefter, J.; Pittauer, D.; Zubrzycki, S.; Han, P.; Rethemeyer, J.; Mollenhauer, G.

    2016-12-01

    Particulate organic matter (POM) discharged by rivers and deposited offshore their mouths is generally assumed to record an integrated signal from the watershed and therefore provides an archive of past environmental changes. Yet, in large river systems the riverine POM might be trapped in flood plains and the lower reaches resulting in an inefficient transport of POM particularly from the distal parts of the watershed. Further, the POM likely undergoes degradation during transport from source to sink. The Lena River is one of these large river systems stretching from 53°N to 71°N in central Siberia. The watershed can be broadly divided into two different biomes, taiga in the south and tundra in the northernmost part. The relative contribution of these biomes to the POM load of the river and its discharge to the ocean as well as the changes it is undergoing during transport are not well understood. Here we present the lignin phenol composition of different grain size fractions (bulk, 2mm-63µm, <63µm) of soil samples taken along a latitudinal transect (63°N to 72°N) as well as in marine surface sediments and two short sediment cores covering the last 120 years offshore the main Lena discharge channels. The lignin phenol composition of the soil samples (bulk, 2mm-63µm, <63µm) reflects the change in vegetation from south to north with increasing contribution of tundra vegetation. The degree of degradation between the soil sample locations as well as grain size fractions was very heterogeneous and did not show a clear trend. However, the POM seems to be slightly more degraded in the tundra, which is unexpected as the summer period when degradation in the upper thawed part of the soil can take place is shorter in the tundra compared to the southern taiga region. The marine surface sediments were dominated by gymnosperm-derived POM, particularly close to the river mouth and in the <63µm fraction. Because of the large heterogeneity of organic matter degradation

  19. Self-consolidation mechanism of porous-surfaced Ti implant compacts induced by electro-discharge-sintering of spherical Ti powders

    NASA Astrophysics Data System (ADS)

    Jo, Y. H.; Kim, Y. H.; Jo, Y. J.; Seong, J. G.; Chang, S. Y.; Reucroft, P. J.; Kim, S. B.; Lee, W. H.

    2015-03-01

    Porous-surfaced Ti implant compacts, with a solid core surrounded by a porous layer, were self-assembled by electro-discharge-sintering directly from spherical Ti powders. During an electro-discharge, instant high temperatures through the Ti powder column ranged from 1093 to 4925 °C were generated in times as short as 86-153 µsec. At the same time, pinch pressures ranging from 11 to 38 MPa were applied, especially to the middle of the Ti powder column. The solid core size depended on both the pinch pressure magnitude and the heat generated during a discharge. Both the pinch pressure (to squeeze and deform Ti powder particles), and the heat (to weld them together), were key factors in the production of porous-surfaced Ti implant compacts. It is thus suggested that the input energy at constant capacitance is a controllable electro-discharge parameter affecting the porosity and strength of the porous-surfaced Ti implant compacts.

  20. Simulated long-term changes in river discharge and soil moisture due to global warming

    USGS Publications Warehouse

    Manabe, S.; Milly, P.C.D.; Wetherald, R.

    2004-01-01

    By use of a coupled ocean atmosphere-land model, this study explores the changes of water availability, as measured by river discharge and soil moisture, that could occur by the middle of the 21st century in response to combined increases of greenhouse gases and sulphate aerosols based upon the "IS92a" scenario. In addition, it presents the simulated change in water availability that might be realized in a few centuries in response to a quadrupling of CO2 concentration in the atmosphere. Averaging the results over extended periods, the radiatively forced changes, which are very similar between the two sets of experiments, were successfully extracted. The analysis indicates that the discharges from Arctic rivers such as the Mackenzie and Ob' increase by up to 20% (of the pre-Industrial Period level) by the middle of the 21st century and by up to 40% or more in a few centuries. In the tropics, the discharges from the Amazonas and Ganga-Brahmaputra rivers increase substantially. However, the percentage changes in runoff from other tropical and many mid-latitude rivers are smaller, with both positive and negative signs. For soil moisture, the results of this study indicate reductions during much of the year in many semiarid regions of the world, such as the southwestern region of North America, the northeastern region of China, the Mediterranean coast of Europe, and the grasslands of Australia and Africa. As a percentage, the reduction is particularly large during the dry season. From middle to high latitudes of the Northern Hemisphere, soil moisture decreases in summer but increases in winter.

  1. Discharge forecasting using MODIS and radar altimetry: potential application for transboundary flood risk management in Niger-Benue River basin

    NASA Astrophysics Data System (ADS)

    Tarpanelli, Angelica; Amarnath, Giriraj; Brocca, Luca; Moramarco, Tommaso

    2016-04-01

    Flooding is one of most widespread natural disasters in the world. Its impact is particularly severe and destructive in Asia and Africa, because the living conditions of some settlements are inadequate to cope with this type of natural hazard. In this context, the estimation of discharge is extremely important to address water management and flood risk assessment. However, the inadequate monitoring network hampers any control and prediction activity that could improve these disastrous situations. In the last few years, remote sensing sensors have demonstrated their effectiveness in retrieving river discharge, especially in supporting discharge nowcasting and forecasting activities. Recently, the potential of radar altimetry was apparent when used for estimating water levels in an ungauged river site with good accuracy. It has also become a very useful tool for estimation and prediction of river discharge. However, the low temporal resolution of radar altimeter observations (10 or 35 days, depending on the satellite mission) may be not suitable for day-by-day hydrological forecasting. Differently, MODerate resolution Imaging Spectroradiometer (MODIS), considering its proven potential for quantifying the variations in discharge of the rivers at daily time resolution may be more suited to this end. For these reasons, MODIS and radar altimetry data were used in this study to predicting and forecasting the river discharge along the Niger-Benue River, where severe flooding with extensive damage to property and loss of lives occurred. Therefore, an effective method to forecast flooding can support efforts towards creating an early warning system. In order to estimate river discharge, four MODIS products (daily, 8-day, and from AQUA and TERRA satellites) connected at three sites (two gauged and one ungauged) were used. The capability of remote sensing sensors to forecast discharge a few days in advance at a downstream section using MODIS and ENVISAT radar altimetry data

  2. A joined multi-metric calibration of river discharge and nitrate loads with different performance measures

    NASA Astrophysics Data System (ADS)

    Haas, Marcelo B.; Guse, Björn; Pfannerstill, Matthias; Fohrer, Nicola

    2016-05-01

    Hydrological models are useful tools to investigate hydrology and water quality in catchments. The calibration of these models is a crucial step to adapt the model to the catchment conditions, allowing effective simulations of environmental processes. In the model calibration, different performance measures need to be considered to represent different hydrology and water quality conditions in combination. This study presents a joined multi-metric calibration of discharge and nitrate loads simulated with the ecohydrological model SWAT. For this purpose, a calibration approach based on flow duration curves (FDC) is advanced by also considering nitrate duration curves (NDC). Five segments of FDCs and of NDCs are evaluated separately to consider the different phases of hydrograph and nitrograph. To consider both magnitude and dynamics in river discharge and nitrate loads, the Kling-Gupta Efficiency (KGE) is used additionally as a statistical performance metric to achieve a joined multi-variable calibration. The results show that a separate assessment of five different magnitudes improves the calibrated nitrate loads. Subsequently, adequate model runs with good performance for different hydrological conditions both for discharge and nitrate are detected in a joined approach based on FDC, NDC, and KGE. In that manner, plausible results were obtained for discharge and nitrate loads in the same model run. Using a multi-metric performance approach, the simultaneous multi-variable calibration led to a balanced model result for all magnitudes of discharge and nitrate loads.

  3. Extensional tectonic influence on lower and upper cretaceous stratigraphy and reservoirs, southern Powder River basin, Wyoming

    SciTech Connect

    Mitchell, G.C.; Rogers, M.H.

    1993-04-01

    The southern Powder River basin has been influenced significantly by an extensional system affecting Lower Cretaceous, Upper Cretaceous and Tertiary units. The system is composed of small throw, nearly vertical normal faults which are identified in the Cretaceous marine shales and that we believe are basement derived. Resultant fractures were present at erosional/depositional surfaces, both marine and nonmarine, that, in part, controlled erosion and subsequent deposition of Lower and Upper Cretaceous rocks. The normal faults also affected coal deposition in the Tertiary, now exposed at the surface. The erosion and resultant deposition formed extensive stratigraphic traps in Cretaceous units in both conventional and unconventional reservoirs. These reservoirs are interbedded with mature source rocks that have generated and expelled large amounts of hydrocarbons. Resulting overpressuring in the Fall River through the Niobrara formations has kept fractures open and has preserved primary porosity in the reservoirs. The normal faults offset thin sandstone reservoirs forming permeability barriers. Associated fractures may have provided vertical pathways for organic acids that assisted development of secondary porosity in Upper Cretaceous sandstones. These normal...faults and fractures provide significant potential for the use of horizontal drilling techniques to evaluate fractured, overpressured conventional and unconventional reservoirs.

  4. Petrographic analyses of Knobloch coal seam (Paleocene), Powder River County, southeastern Montana

    SciTech Connect

    Daniel, J.A.

    1986-08-01

    A single core of Knobloch coal from Powder River County, southeast Montana, was drilled to obtain samples for coal quality studies. The coal occurs in the lower Tongue River Member of the Paleocene Fort Union Formation. The Knobloch coal core (63 ft long) was divided into 1-ft increments and analyzed using chemical and petrographic methods. Definite variations in maceral content were seen. Preliminary studies show relationship between ash, gelinite, inertinite, and humodetrinite contents. A zone of low gelinite, low humodetrinite, and high inertinite, located in the lower quarter of the seam, implies a period of severe oxidation occurred, possibly as swamp fires. Four zones of high inertinite and high humodetrinite (three in the upper half and one in the lower half of the seam) indicate fluctuations in the water table, allowing moderate oxidation and weathering of plant material and subsequent mechanical reworking of humic grains. Near the center of the seam, a zone of high inertinite, high humodetrinite, and high ash content suggests water levels were high enough to allow significant sediment influx as well as reworking of the humic materials. These conclusions suggest the Knobloch coal is autochthonous and hypautochthonous in origin, a result of several water-table fluctuations and/or climatic changes due to drought.

  5. Determination of major nonmetallic impurities in magnesium by glow discharge mass spectrometry with a fast flow source using sintered and pressed powder samples.

    PubMed

    Plotnikov, Alexei; Pfeifer, Jens; Richter, Silke; Kipphardt, Heinrich; Hoffmann, Volker

    2014-11-01

    Fast flow glow discharge mass spectrometry with a Grimm-type ion source providing a high sputter rate was used for the determination of major nonmetallic impurities in magnesium. The analytical signal was found to be strongly influenced by the electrical discharge parameters. For calibration by standard addition, synthetic standard samples were produced in two different ways-namely, by pressing and by sintering doped metal powders. The observed sensitivity of the calibration curves was shown to depend on the particle size of the powder. For the magnesium powders, the mass fractions of oxygen, nitrogen, boron, and silicon were determined to be about 0.01 kg·kg(-1) (relative standard deviation approximately 10-20 %), 2,700 mg·kg(-1), 150 mg·kg(-1), and 300 mg·kg(-1), respectively.

  6. Plunge location of sediment driven hyperpycnal river discharges considering bottom friction, lateral entrainment, and particle settling

    NASA Astrophysics Data System (ADS)

    Strom, K. B.; Bhattacharya, J.

    2012-12-01

    River discharges with very high sediment loads have the potential to develop into plunging hyperpycnal flows that transition from a river jet to a turbidity current at some location basinward of the river mouth due to the density difference between the turbid river and the receiving water body. However, even if the bulk density of the turbid river is greater than that of the receiving lake or ocean, some distance is needed for the forward inertia of the river to dissipate so that the downward gravitational pull can cause the system to collapse into a subaqueous turbidity current. This collapsing at the plunge point has been found to occur when the densimetric Froude number decreases to a value between 0.3 < Frd < 0.7 (Fang and Stefan 2000, Parker and Toniolo 2007, Dai and Garcia 2010, Lamb et al. 2010). In 2D channel flow analysis at the plunge point, this has led to the concept of a two-fold criterion for plunging. The first is simply for the need of high enough suspended sediment concentration to overcome the density difference between the river fluid and the fluid of the receiving water. The second is the need for sufficiently deep water to reduce the densimetric Froude below the critical value for plunging, which leads to dependence of plunging on the receiving water basin topography (Lamb et al. 2010). In this analysis, we expand on past work by solving a system of ODE river jet equations to account for bottom friction, lateral entrainment of ambient fluid, and particle settling between the river mouth and the plunge location. Typical entrainment and bottom friction coefficients are used and the model is tested against the laboratory density current data of Fang and Stefan (1991). A suite of conditions is solved with variable river discharge velocity, aspect ratio, suspended sediment concentration, and particle size; a range of salinity values and bottom slopes are used for the receiving water body. The plunge location is then expressed as a function of the

  7. Discharge and sediment loads at the Kings River Experimental Forest in the Southern Sierra Nevada of California

    Treesearch

    S.M. Eagan; C.T. Hunsaker; C.R. Dolanc; M.E. Lynch; C.R. Johnson

    2007-01-01

    The Kings River Experimental Watershed (KREW) is now in its third year of data collection on eight small perennial watersheds. We are collecting meteorology, stream discharge, sediment load, water chemistry, shallow soil water chemistry, vegetation, macro-invertebrate, stream microclimate, and air quality data. This paper primarily examines discharge and sediment data...

  8. A study on river discharge and salinity variability in the Middle Atlantic Bight and Long Island Sound

    NASA Astrophysics Data System (ADS)

    Whitney, Michael M.

    2010-02-01

    This study quantitatively characterizes annual, interannual, and decadal variability of Middle Atlantic Bight (MAB) river discharges, MAB surface salinities, Long Island Sound (LIS) surface salinities, and LIS salinity stratification via wavelet analysis. Links among rivers, salinities, and standard climate indices are investigated through correlation analysis of the complete data records and low-pass time series (including periods greater than 1.5 years). All rivers and salinities analyzed have strong annual cycles that are distinguishable from random noise. All records have interannual power, but this variability is indistinguishable from the noise background. Some MAB rivers have significant multi-decadal power (near either 18-year or 26-year periods). Correlations are strong among MAB rivers, salinities at different shelf sections, and salinities at LIS stations. Negative correlations between MAB rivers and surface salinities account for a significant part of the observed variance: up to 29% for shelf salinities and 46% for LIS salinities. Shelf and estuary salinities are positively correlated; accounting for at most 61% of the variance. LIS salinity stratification is positively correlated with river discharge (up to 36% of the variance). Interannual variability exhibits similar statistical relationships with higher correlations. Average annual cycles indicate a 1-2-month sequential lag between peak river discharge, minimum estuary salinity, and minimum shelf salinity. Weak but significant correlations indicate a tendency for high discharge, low LIS salinity, and high LIS stratification to coincide with positive intervals of the North Atlantic Oscillation Index.

  9. Low-flow characteristics and discharge profiles for selected streams in the Neuse River basin, North Carolina

    USGS Publications Warehouse

    Weaver, J.C.

    1998-01-01

    An understanding of the magnitude and frequency of low-flow discharges is an important part of evaluating surface-water resources and planning for municipal and industrial economic expansion. Low-flow characteristics are summarized in this report for 50 continuous-record gaging stations and 113 partial-record measuring sites in the Neuse River Basin in North Carolina. Records of discharge collected through the 1996 water year were used in the analyses. Flow characteristics included in the summary are (1) average annual unit flow; (2) 7Q10 low-flow discharge, the minimum average discharge for a 7-consecutive-day period occurring, on average, once in 10 years; (3) 30Q2 low-flow discharge; (4) W7Q10 low-flow discharge, similar to 7Q10 discharge except that only flow during November through March is considered; and (5) 7Q2 low-flow discharge.

  10. Geologic history of natural coal-bed fires, Powder River basin, USA

    USGS Publications Warehouse

    Heffern, E.L.; Coates, D.A.

    2004-01-01

    Coal-bed fires ignited by natural processes have baked and fused overlying sediments to form clinker, a hard red or varicolored rock, through much of the northern Great Plains of the United States (USA). The gently dipping coal beds in the region burn when regional downwasting brings them above the local water table. The resulting clinker forms a rim along the exposed edge of the coal bed in an ongoing process through geologic time. The resistant clinker is left capping buttes and ridges after the softer unbaked strata erode away. Clinker outcrops cover more than 4100 km2 in the Powder River basin (PRB), which lies in Wyoming (WY) and Montana (MT). The clinker in place records tens of billions of tons of coal that have burned, releasing gases into the atmosphere. The amount of clinker that has eroded away was at least an order of magnitude greater than the clinker that remains in place. Fission-track and uranium-thorium/ helium ages of detrital zircon crystals in clinker, and paleomagnetic ages of clinker, show that coal beds have burned naturally during at least the past 4 million years (Ma). The oldest in-place clinker that has been dated, collected from a high, isolated, clinker-capped ridge, has a fission track age of 2.8??0.6 Ma. Evidence of erosion and downcutting is also preserved by clinker clasts in gravel terraces. One clinker boulder in a terrace 360 m above the Yellowstone River has a fission track age of 4.0??0.7 Ma. Coal-bed fires are caused by lightning, wildfires, spontaneous combustion, or human activity on coal outcrops and in mines. Miners, government agencies, and ranchers have extinguished thousands of coal bed fires, but natural ignition continues where fresh coal has access to air. At any given time, hundreds of fires, mostly small, are burning. In the Powder River basin, the total amount of coal burned by natural fires in the last 2 Ma is one to two orders of magnitude greater than the total amount of coal removed by mining in the past

  11. Early Holocene Sediment Discharge from Taiwanese Rivers: Intensified Asian Monsoon and Climate Change

    NASA Astrophysics Data System (ADS)

    Hsu, Ho-Han; Liu, Char-Shine; Milliman, John; Chen, Tzu-Ting; Chang, Jih-Hsin; Wang, Yunshuen

    2016-04-01

    Temporal variations of fluvial sediment discharge can reflect the significant climatic variation. In this study, high-resolution sedimentary records - on the millennial scale - from onshore wells, offshore cores and seismic profiles are used to quantify sediment discharge from small mountainous rivers around Taiwan since the last glacial maximum. While significantly high sediment accumulation rates have been observed in the modern flood plain, shelf and deep-sea basins during the late Pleistocene and Holocene, early Holocene rates are unusually high. In northeast Taiwan, for example, sediment flux from the Lanyang River between 10-12 ka BP appears to have been 10 mt/yr, about 4 fold greater than measured annual discharge prior to 1960. In the southwest Taiwan, the highest sedimentation rate happened during 10-12 ka BP. Long-term average discharge since 8 ka BP has been ~12 mt/yr), less than half the 29 mt/yr that was deposited on the Kaohsiung-Pingtung Plain. These and other sedimentation histories around Taiwan as well as in the South China Sea and the Bay of Bengal indicate that the occurrence of high sediment load cannot be explained solely by general circulation model of sea-level change; climate and climatic change also should be taken into account. We suggest that the intensification of the Asian monsoon, particularly in the case of Taiwan, typhoons, which occurred during the early Holocene may have been the root cause of the increased rainfall and thus increased erosion and sediment delivery. This study reconstructs the long-term sedimentary history of the region since the late Quaternary, especially focuses on the increased sediment discharges during the particularly warm and humid paleo-climatic period in NE and SW Taiwan. Moreover, it could help to better understand and predict fluvial sediment fluxes and their geological and societal impacts in response to future global warming.

  12. Do sewage treatment plant discharges substantially impair fish reproduction in polluted rivers?

    PubMed

    Douxfils, Jessica; Jessica, Douxfils; Mandiki, Robert; Robert, Mandiki; Silvestre, Frédéric; Frédéric, Silvestre; Bertrand, Arnaud; Arnaud, Bertrand; Leroy, Delphine; Delphine, Leroy; Thomé, Jean-Pierre; Jean-Pierre, Thomé; Kestemont, Patrick; Patrick, Kestemont

    2007-01-01

    Sewage treatment plants are frequently associated with the release of xenobiotics and, consequently, with alterations of the reproductive function induced by many of these substances in aquatic organisms. In order to assess the impacts of sewage treatment plant (STP) discharges in polluted rivers, two sentinel species (gudgeon Gobio gobio and stoneloach Barbatula barbatula) were caught during their reproductive cycle upstream and downstream two STPs (STP1--Goffontaine, STP2--Wegnez). Gonadosomatic index, histological (testicular and ovarian stages, atretic follicles, intersexuality) and endocrine (sex steroids, aromatase activity, alkali-labile phosphorus) parameters were assayed. In brief, the results revealed no systematic significant differences (p<0.05) between upstream and downstream sites, whatever the STP, species or sampling period. However, stoneloach females displayed some signs of reproductive impairment and endocrine disruption downstream STP1 (reduced GSI, oocyte diameter and ALP concentrations, increased proportion of atretic follicles) and STP2 (changes in gonadal aromatase activity and plasma levels of 11-KT and T). Few significant changes were observed for gudgeon males and females while there were no significant differences between upstream and downstream sites for stoneloach males. Moreover, plasma E(2) concentrations recorded in gudgeon males sampled in all sites were as high as in females and this was confirmed by high ALP levels. Besides, spermatogenesis of gudgeon males was delayed in STP1 upstream and downstream sites compared to the corresponding sites in STP2. These observations for gudgeon males do not seem related to STP discharge but to a probable estrogenicity of the river. Therefore, as shown by the results, stoneloach seemed more sensitive than gudgeon to STP discharges. In the present study, sewage treatment plant discharges do not substantially impair fish reproduction. In this respect, caution is required when generalising

  13. Hydrologic properties of coal beds in the Powder River Basin, Montana I. Geophysical log analysis

    USGS Publications Warehouse

    Morin, R.H.

    2005-01-01

    As part of a multidisciplinary investigation designed to assess the implications of coal-bed methane development on water resources for the Powder River Basin of southeastern Montana, six wells were drilled through Paleocene-age coal beds along a 31-km east-west transect within the Tongue River drainage basin. Analysis of geophysical logs obtained in these wells provides insight into the hydrostratigraphic characteristics of the coal and interbedded siliciclastic rocks and their possible interaction with the local stress field. Natural gamma and electrical resistivity logs were effective in distinguishing individual coal beds. Full-waveform sonic logs were used to determine elastic properties of the coal and an attendant estimate of aquifer storage is in reasonable agreement with that computed from a pumping test. Inspection of magnetically oriented images of the borehole walls generated from both acoustic and optical televiewers and comparison with coal cores infer a face cleat orientation of approximately N33??E, in close agreement with regional lineament patterns and the northeast trend of the nearby Tongue River. The local tectonic stress field in this physiographic province as inferred from a nearby 1984 earthquake denotes an oblique strike-slip faulting regime with dominant east-west compression and north-south extension. These stress directions are coincident with those of the primary fracture sets identified from the televiewer logs and also with the principle axes of the drawdown ellipse produced from a complementary aquifer test, but oblique to apparent cleat orientation. Consequently, examination of these geophysical logs within the context of local hydrologic characteristics indicates that transverse transmissivity anisotropy in these coals is predominantly controlled by bedding configuration and perhaps a mechanical response to the contemporary stress field rather than solely by cleat structure.

  14. Nekton community response to a large-scale Mississippi River discharge: Examining spatial and temporal response to river management

    USGS Publications Warehouse

    Piazza, Bryan P.; La Peyre, M.K.

    2011-01-01

    Freshwater flow is generally held to be one of the most influential factors affecting community structure and production in estuaries. In coastal Louisiana, the Caernarvon Freshwater Diversion (CFD) is managed to control freshwater discharge from the Mississippi River into Breton Sound basin. Operational since 1991, CFD has undergone several changes in management strategy including pulsed spring flooding, which was introduced in 2001. We used a 20-yr time series of fisheries-independent data to investigate how variation in freshwater inflow (i.e., pre- and post-CFD, and pre and post spring pulsing management) influences the downstream nekton community (abundance, diversity, and assemblage). Analyses of long-term data demonstrated that while there were effects from the CFD, they largely involved subtle changes in community structure. Spatially, effects were largely limited to the sites immediately downstream of the diversion and extended only occasionally to more down-estuary sites. Temporally, effects were 1) immediate (detected during spring diversion events) or 2) delayed (detected several months post-diversion). Analysis of river management found that pulsed spring-time inflow resulted in more significant changes in nekton assemblages, likely due to higher discharge rates that 1) increased marsh flooding, thus increasing marsh habitat accessibility for small resident marsh species, and 2) reduced salinity, possibly causing displacement of marine pelagic species down estuary. ?? 2010.

  15. Dependency of high coastal water level and river discharge at the global scale

    NASA Astrophysics Data System (ADS)

    Ward, Philip; Haigh, Ivan; Muis, Sanne; Veldkamp, Ted; Wahl, Thomas

    2017-04-01

    It is widely recognized that floods cause huge socioeconomic impacts. From 1980-2013, global flood losses exceeded 1 trillion, with 220,000 fatalities. These impacts are particularly hard felt in low-lying densely populated deltas and estuaries, whose location at the coast-land interface makes them naturally prone to flooding. When river and coastal floods coincide, their impacts in these deltas and estuaries are often worse than when they occur in isolation. Such floods are examples of so-called 'compound events'. In this paper, we present the first global scale analysis of the statistical dependency of high coastal water levels (and the storm surge component alone) and river discharge. This is essential for understanding the likelihood of compound flood events occurring at locations around the world as well as for accurate flood risk assessments and effective flood risk management. To date, most flood risk assessments at the large scale assume statistical independence between coastal and river flooding. However, several local and continental studies in recent years have shown that this is not the case. We analysed the statistical dependency between observed coastal water levels (and the storm surge component) and river discharge using gauged data from stations all around the world. We show that the relationship is strong over large regions of the world. We use copula functions to show how the likelihood of design events is strongly influenced by this dependency; when the dependency is included, the likelihood of flood defence failure is higher than when statistical independence is assumed. Nevertheless, the gauged data used in this study provide an incomplete picture, since there are large parts of the world for which no data are available. We therefore discuss our ongoing modelling approaches to more thoroughly assess the dependency of coastal and river floods, and to carry out risk assessments that account for this dependency.

  16. Monitoring of coalbed water retention ponds in the Powder River Basin using Google Earth images and an Unmanned Aircraft System

    NASA Astrophysics Data System (ADS)

    Zhou, X.; Zhou, Z.; Apple, M. E.; Spangler, L.

    2016-12-01

    To extract methane from unminable seams of coal in the Powder River Basin of Montana and Wyoming, coalbed methane (CBM) water has to be pumped and kept in retention ponds rather than discharged to the vadose zone to mix with the ground water. The water areal coverage of these ponds changes due to evaporation and repetitive refilling. The water quality also changes due to growing of microalgae (unicellular or filamentous including green algae and diatoms), evaporation, and refilling. To estimate the water coverage changes and monitor water quality becomes important for monitoring the CBM water retention ponds to provide timely management plan for the newly pumped CBM water. Conventional methods such as various water indices based on multi-spectral satellite data such as Landsat because of the small pond size ( 100mx100m scale) and low spatial resolution ( 30m scale) of the satellite data. In this study we will present new methods to estimate water coverage and water quality changes using Google Earth images and images collected from an unmanned aircraft system (UAS) (Phantom 2 plus). Because these images have only visible bands (red, green, and blue bands), the conventional water index methods that involve near-infrared bands do not work. We design a new method just based on the visible bands to automatically extract water pixels and the intensity of the water pixel as a proxy for water quality after a series of image processing such as georeferencing, resampling, filtering, etc. Differential GPS positions along the water edges were collected the same day as the images collected from the UAS. Area of the water area was calculated from the GPS positions and used for the validation of the method. Because of the very high resolution ( 10-30 cm scale), the water areal coverage and water quality distribution can be accurately estimated. Since the UAS can be flied any time, water area and quality information can be collected timely.

  17. The impact of land data assimilation on global river discharge predictions

    NASA Astrophysics Data System (ADS)

    Zsoter, Ervin; Cloke, Hannah; Smith, Paul; Emerton, Rebecca; Muñoz-Sabater, Joaquín; Pappenberger, Florian

    2017-04-01

    Operational probabilistic flood forecasts have become common in supporting decision-making processes and providing a platform to risk reduction. The Global Flood Awareness System (GloFAS) is one of the few global scale applications that currently exist. GloFAS is developed by the Joint Research Centre of the European Commission (JRC) and the European Centre for Medium-Range Weather Forecasts (ECMWF) with the support of national authorities and research institutions. It couples state-of-the art weather forecasts with a hydrological model to produce daily ensemble forecasts of river discharge with a forecast horizon of 30 days across a global river network. In GloFAS the real time streamflow forecasts are compared with climatological simulations to detect the severity of any high flow situations. In the current configuration, runoff produced "offline", where the ECMWF land-surface model (HTESSEL) is forced with atmospheric conditions from ERA Interim reanalysis, and runoff produced operationally in coupled mode with land data assimilation, are both used. This inhomogeneity of the application of land data assimilation in different parts of the GloFAS system can cause significant differences in river discharge and therefore limit the reliability of the flood severity information determined by comparing the real time forecasts to the historical discharge. In this study we evaluate the potential impact of the land data assimilation on discharge forecasting in the global context. The analysis is based on the new ERA5 climate reanalysis dataset covering the period 1979 to present and developed through the Copernicus Climate Change Service (C3S). ERA5 is the 5th major global reanalysis produced by ECMWF, following FGGE, ERA-15, ERA-40 and ERA-Interim. This version consists of a high resolution reanalysis dataset (31 km), and additionally includes information on uncertainties based on 10 ensemble members at 62 km horizontal resolution. ERA5 is currently in production and the

  18. The influence of major rivers discharges on physical and biological state of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Dudkowska, Aleksandra; Cieszyńska, Agata

    2017-04-01

    River discharges are one of very important factors affecting the marine ecosystem functioning. Land-originated inflows, carrying fresh, nutrient-rich water can be often defined as the factor responsible for creating new physical and biochemical conditions, which in turn can create more or less favorable medium for many marine organisms to run their biological cycles within. In some basins, the Baltic Sea including, land-originated water inflows are usually associated with the eutrophication and are the factors, which trigger this process. It is clear that not only because of the riverine discharges, the nutrients levels in the sea increase. To exemplify in the case of phosphorus, the nutrient concentration can be raised by 'internal re-loading', which is caused by phosphorus pools accumulated in the sediments of the sea bed being released back to the water under anoxic conditions. In the present study, we focused on the major Baltic rivers inflows and their impact on the environmental state of the basin. We have examined river discharges (expressed as volumetric inflow in m3 s-1) and the nutrient load (phosphorus, nitrogen) accompanied by these inflows. Data for our investigation were derived from EHype model (Swedish Meteorological Institute Server, http://hypeweb.smhi.se/europehype/time-series/). From the river discharge model data set spanned over 1981 - 2010, we have calculated long-term trends and the basic statistics: annual and monthly means, percentiles (10th, 50th, 90th). The trends were defined to be statistically significant at the confidence level of 95% (p < 0.05). What is more, we have estimated the inflows extent and related to tributaries changes in three-dimensional distribution of seawater physical properties on the basis of hydrodynamic model. Land-sea interface comprise an important link in the water body state analysis. This research comprises a discussion of river runoffs significance evaluation in the Baltic Sea area. This work has been

  19. Impact of climate change on river discharge in the Teteriv River basin (Ukraine)

    NASA Astrophysics Data System (ADS)

    Didovets, Iulii; Lobanova, Anastasia; Krysanova, Valentina; Snizhko, Sergiy; Bronstert, Axel

    2016-04-01

    The problem of water resources availability in the climate change context arises now in many countries. Ukraine is characterized by a relatively low availability of water resources compared to other countries. It is the 111th among 152 countries by the amount of domestic water resources available per capita. To ensure socio-economic development of the region and to adapt to climate change, a comprehensive assessment of potential changes in qualitative and quantitative characteristics of water resources in the region is needed. The focus of our study is the Teteriv River basin located in northern Ukraine within three administrative districts covering the area of 15,300 km2. The Teteriv is the right largest tributary of the Dnipro River, which is the fourth longest river in Europe. The water resources in the region are intensively used in industry, communal infrastructure, and agriculture. This is evidenced by a large number of dams and industrial objects which have been constructed from the early 20th century. For success of the study, it was necessary to apply a comprehensive hydrological model, tested in similar natural conditions. Therefore, an eco-hydrological model SWIM with the daily time step was applied, as this model was used previously for climate impact assessment in many similar river basins on the European territory. The model was set up, calibrated and validated for the gauge Ivankiv located close to the outlet of the Teteriv River. The Nash-Sutcliffe efficiency coefficient for the calibration period is 0.79 (0.86), and percent bias is 4,9% (-3.6%) with the daily (monthly) time step. The future climate scenarios were selected from the IMPRESSIONS (Impacts and Risks from High-End Scenarios: Strategies for Innovative Solutions, www.impressions-project.eu) project, which developed 7 climate scenarios under RCP4.5 and RCP8.5 based on GCMs and downscaled using RCMs. The results of climate impact assessment for the Teteriv River basin will be presented.

  20. Decline of Yangtze River water and sediment discharge: Impact from natural and anthropogenic changes

    PubMed Central

    Yang, S. L.; Xu, K. H.; Milliman, J. D.; Yang, H. F.; Wu, C. S.

    2015-01-01

    The increasing impact of both climatic change and human activities on global river systems necessitates an increasing need to identify and quantify the various drivers and their impacts on fluvial water and sediment discharge. Here we show that mean Yangtze River water discharge of the first decade after the closing of the Three Gorges Dam (TGD) (2003–2012) was 67 km3/yr (7%) lower than that of the previous 50 years (1950–2002), and 126 km3/yr less compared to the relatively wet period of pre-TGD decade (1993–2002). Most (60–70%) of the decline can be attributed to decreased precipitation, the remainder resulting from construction of reservoirs, improved water-soil conservation and increased water consumption. Mean sediment flux decreased by 71% between 1950–1968 and the post-TGD decade, about half of which occurred prior to the pre-TGD decade. Approximately 30% of the total decline and 65% of the decline since 2003 can be attributed to the TGD, 5% and 14% of these declines to precipitation change, and the remaining to other dams and soil conservation within the drainage basin. These findings highlight the degree to which changes in riverine water and sediment discharge can be related with multiple environmental and anthropogenic factors. PMID:26206169

  1. Discharge and water temperature evolution in future climate. A case study on the Rhone river

    NASA Astrophysics Data System (ADS)

    Marie, Bourqui; Moine Nicolas, Le; Frederic, Hendrickx

    2010-05-01

    Discharge and water temperature evolution in future climate. A case study on the Rhone river EDF, as electricity producer, is interested on the future evolution of water temperature and discharge for the rivers where industrial sites are located. In particular, the model of present discharges and water temperatures is done via an hydrological model coupled with water temperature model. Forcing the models with GCM future climate scenarios it is possible to forecast the future evolutions of these two variables. Here a case study on the cross-boarder Rhone basin at the section of Viviers (73,000 km², France) is presented. This watershed presents very particular characteristics, namely the influence of the Leman lake on the upstream part of the basins and the presence of several tributary characterized by various hydrological regimes. For this reason, the hydrological modeling is a key in the future climate evolution estimation. A very wide data set of meteorological measure (collected by EDF during the last 35 years) is used to calibrate the models. The selected future scenarios are issued from the results of 6 coupled model RCM-GCM of the European project Ensemble.

  2. Metal discharges by Sinaloa Rivers to the coastal zone of NW Mexico.

    PubMed

    Frías-Espericueta, M G; Mejía-Cruz, R; Osuna López, I; Muy-Rangel, M D; Rubio-Carrasco, W; Aguilar-Juárez, M; Voltolina, D

    2014-02-01

    The aim of this work was to survey the discharges of dissolved and particulate Cd, Cu, Fe, Mn, Pb and Zn of the eight main rivers of Sinaloa State to the Mexican coastal environment. Zn was the most abundant dissolved metal and Fe was the most abundant particulate (8.02-16.90 and 51.8-1,140.3 μg/L, respectively). Only particulate Mn had significantly (p = 0.028) higher values in summer-fall (rainy season), whereas the significantly (p = 0.036) higher values of dissolved Zn were observed in winter and spring. The highest annual total discharges to Sinaloa coastal waters were those of the rivers San Lorenzo and Piaxtla (>2 × 10(3) m.t.) and the lowest those of rivers Baluarte and El Fuerte (349 and 119 m.t., respectively). Pb concentrations may become of concern, because they are higher than the value recommended for the welfare of aquatic communities of natural waters.

  3. Identifying Groundwater Discharge in the Merced River Basin, California Using Radon-222

    NASA Astrophysics Data System (ADS)

    Shaw, G. D.; Hudson, G. B.; Moran, J.; Conklin, M.

    2004-12-01

    Groundwater flow in fractured granite of the Sierra Nevada is poorly characterized, in particular, contributions of mountain block recharge are not known. Using a combination of water quality and isotopic analyses, groundwater inputs to the Upper Merced River were characterized. Between November 2003 and July 2004, monthly water quality samples were taken from Happy Isles to the inlet of Lake McClure, a 75 km reach. These samples demonstrated the expected dilution due to snowmelt in the spring. In the fall, the spatial profile matched the geology with anion concentrations increasing downstream of the transition from the Sierra Nevada batholith to the country rock, suggesting significant groundwater inputs. From July 19 to 21, 2004, radon-222 and other noble gases (He, Ne, Ar, Kr and Xe abundances and 3He/4He ratio) were measured along a 37 km reach of the Merced River, extending from the top of Yosemite Valley to the confluence of the South Fork of the Merced River. All radon samples were extracted into mineral oil immediately in the field and counted using liquid scintillation; noble gas samples were collected in copper tubes. Radon-222 activity varied from about 1 to 100 pCi/L (at collection time) indicating significant, spatially variable groundwater discharge into the Merced River. Two one-mile reaches of the Merced River were sampled for 222Rn on a fine scale. Large fracture sets in these two locations and previous temperature measurements suggested that groundwater discharge was higher relative to other locations along the river. Radon-222 activity was low upstream and downstream of large fractures observed in the bedrock; whereas, 222Rn activity was high at large fracture zones. Degassing is rapid downstream of fractures where no groundwater discharge is observed. For a representative groundwater end-member, radon-222 activity measured in Fern Spring, Yosemite Valley was about 1200 pCi/L. Excess 4He from U and Th decay is observed in samples with elevated

  4. The evolution of an ephemeral river during the rising and receding phases of medium and low magnitude discharge events

    NASA Astrophysics Data System (ADS)

    Lotsari, E. S.; Calle, M.; Benito-Ferrandez, G.; Kaartinen, H.; Kukko, A.; Hyyppä, J.; Hyyppä, H.; Alho, P.

    2015-12-01

    In addition to great flash floods, medium and low magnitude discharge events can also cause great morphological changes in ephemeral river channels. Despite the advances in measurement techniques, such as laser scanning, and simulation approaches, the channel evolution during the different phases of discharge events is still not well known in gravelly ephemeral rivers, such as Rambla de la Viuda (Spain). The aim is to detect the temporal evolution of the ephemeral river channel during consecutive medium (March 2013) and low (May 2013) magnitude discharge events. The study is based on both accurate topographical measurements (laser scanning) and morphodynamic simulations (Delft 2D). Before the final analysis, the model's performance was tested with different parameterizations. When compared to the observed channel changes, the transport equation had crucial role in simulation results. Engelund-Hansen equation succeeded the best. It was important to use spatially varying grain sizes. Erosion and deposition (m3) were the greatest during the first hours of the rising phase of the discharge events. After this, erosion and deposition amounts, which were detected hourly, started declining. Thus, this occurred before the peak discharge, and erosion slowed down more than deposition. After the discharge peak, changes in deposition and erosion amounts were slightly more gradual than changes in discharge. The deposition during the receding phase was due to the advancing bar lobe frontier. River bed changes followed temporally the changes in discharges during the receding phase. This was different to the rising phase, when temporal differences occurred between changes in discharges and changes in deposition and erosion. This study shows that both rising and receding phases of discharge events are important for bar movement and channel evolution of the gravelly ephemeral river.

  5. Effect of gold mining activities on water turbidity and river sediment discharge: comparison of two nearby river basin in French Guiana, using remote sensing and field measurements data

    NASA Astrophysics Data System (ADS)

    Marjorie, Gallay; Jean-Michel, Martinez; Alain, Laraque; Max, Sarrazin; Jean-Claude, Doudou; Antoine, Gardel; Vincent, Vantrepotte; Franck, Chow-Toun

    2016-04-01

    The Maroni and Oyapock rivers are two nearby basin in French Guiana, South America. The Maroni river drains a basin of 66 000 km² between French Guiana and Surinam. The Oyapock river basin covers 28 000 km² over French Guiana and Brazil. The Both over the Guyana shield presenting very lowest erosion rates. For both rivers, Suspended Sediment Concentration and remote sensing reflectance have been determined, during 3 fields sampling campaigns, using TriOs RAMSES radiometers operating in the 350-900 nm spectral range. Field data are compared with MODIS spaceborne sensors onboard calibration Terra and Aqua satellites. For the first time over the Maroni river, we show that it is possible to monitored from space both Surface Suspended Sediment Concentration (SSSC) and the Turbidity (R²=0,81), making possible to evaluate water quality long term. Combining fields and satellite derived SSSC measurements, we detected an increase of median SSSC (20 to 30 mg/l)and sediment budget in the Maroni river and a stability for the Oyapock river (10 mg/l), since 2000. Almost, relationship between SSSC and river water discharge was investigated for both rivers and for the 2000-2015 period. We show that SSSC and Maroni river discharge present decreasing correlation over the period of study. For the Oyapock River, SSSC and river discharge show good relationship over the period of study. Analysis of land-use change in the Maroni catchment showed an important increase of areas affected by gold mining which explain the observed modification of the Maroni River Suspended Sediment budget.

  6. Fecal coliform accumulation within a river subject to seasonally-disinfected wastewater discharges.

    PubMed

    Mitch, Azalea A; Gasner, Katherine C; Mitch, William A

    2010-09-01

    As pathogen contamination is a leading cause of surface water impairment, there has been increasing interest in the implications of seasonal disinfection practices of wastewater effluents for meeting water quality goals. For receiving waters designated for recreational use, disinfection during the winter months is often considered unnecessary due to reduced recreational usage, and assumptions that lower temperatures may reduce pathogen accumulation. For a river subject to seasonal disinfection, we sought to evaluate whether fecal coliforms accumulate during the winter to concentrations that would impair river water quality. Samples were collected from municipal wastewater outfalls along the river, as well as upstream and downstream of each outfall during the winter, when disinfection is not practiced, and during the summer, when disinfection is practiced. During both seasons, fecal coliform concentrations reached 2000-5000 CFU/100 mL, nearly an order of magnitude higher than levels targeted for the river to achieve primary contact recreational uses. During the summer, wastewater effluents were not significant contributors to fecal coliform loadings to the river. During the winter, fecal coliform accumulated along the river predominantly due to loadings from successive wastewater outfalls. In addition to the exceedance of fecal coliform criteria within the river, the accumulation of wastewater-derived fecal coliform along the river during the winter season suggests that wastewater outfalls may contribute elevated loads of pathogens to the commercial shellfish operations occurring at the mouth of the river. Reductions in fecal coliform concentrations between wastewater outfalls were attributed to dilution or overall removal. Combining discharge measurements from gauging stations, tributaries and wastewater outfalls to estimate seepage, dilution between wastewater outfalls was estimated, along with the percentage of the river deriving from wastewater outfalls. After

  7. Water quality and discharge of streams in the Lehigh River Basin, Pennsylvania

    USGS Publications Warehouse

    McCarren, Edward F.; Keighton, Walter B.

    1969-01-01

    The Lehigh River, 100 miles long, is the second largest tributary to the Delaware River. It drains 1,364 square miles in four physiographic provinces. The Lehigh River basin includes mountainous and forested areas, broad agricultural valleys and areas of urban and industrial development. In the headwaters the water is of good quality and has a low concentration of solutes. Downstream, some tributaries receive coal-mine drainage and become acidic; others drain areas underlain by limestone and acquire alkaline characteristics. The alkaline streams neutralize and dilute the acid mine water where they mix. The dissolved-oxygen content of river water, which is high in the upper reaches of the stream, is reduced in the lower reaches because of lower turbulence, higher temperature, and the respiration of organisms. The Lehigh is used for public supply, recreation, waterpower, irrigation, and mining and other industrial purposes. Because the river is shallow in its upper reaches, most of the water comes in contact with the atmosphere as it churns over rocks and around islets and large boulders. Aeration of the water is rapid. When water that was low in dissolved-oxygen concentration was released from the lower strata of the Francis E. Walter Reservoir in June 1966, it quickly became aerated in the Lehigh River, and for 40 miles downstream from the dam the water was nearly saturated with oxygen. Most of the river water requires only moderate treatment for industrial use and public distribution throughout the Lehigh River valley. At times, however, some segments of the main river and its tributaries transport industrial wastes and acid coal-mine drainage. Usually the relatively high concentrations of solutes in water and the ensuing damage caused to quality by such waste discharges are more extensive and prolonged during droughts and other periods of low streamflow. For many years the Lehigh River flow has been continuously measured and its water chemically analyzed. Since

  8. Large-scale Estimation of River Discharge from SWOT Satellite Observations: A Fraternal Twin Data Assimilation Experiment

    NASA Astrophysics Data System (ADS)

    Andreadis, K.; Moller, D.; Rodriguez, E.; Sanders, B. F.; Bates, P. D.; Chaubell, M.; McCann, M.; Durand, M. T.; Alsdorf, D. E.

    2010-12-01

    The ability to observe and monitor the volume of water stored and flowing in rivers, lakes and wetlands globally is of paramount importance. Nevertheless, river discharge is not measured directly, either by satellite or in-situ methods. The Surface Water and Ocean Topography (SWOT) satellite, a "Decadal Survey" mission, will be able to provide measurements of water surface elevation in both the ocean and land surface. One of the approaches to estimate discharge will be within a multi-scale data assimilation framework that will correct for uncertainties in model predictions. These model errors are caused by uncertainties in precipitation and other meteorological forcings, as well as uncertainties in river channel characteristics such as depth. We present the implementation and evaluation of a data assimilation system that will produce river discharge estimates from SWOT observations of water surface elevation. The experimental design is based on a fraternal twin synthetic experiment, wherein "true" fields of discharge and water elevation are generated from a detailed hydrodynamics model (BreZo). These "true" fields are then fed into the SWOT instrument simulator, in order to generate SWOT observations of water surface elevation with the correct orbital characteristics and error information (wet troposphere, topographic layover effects, etc.). A simpler and computationally efficient hydrodynamics model (LISFLOOD-FP), that includes errors in model parameters and boundary inflows, is then used along with the synthetic SWOT observations to retrieve the "true" river discharge across multiple scales of the Ohio River basin.

  9. Stage-Discharge Relations for the Colorado River in Glen, Marble, and Grand Canyons, Arizona, 1990-2005

    USGS Publications Warehouse

    Hazel, Joseph E.; Kaplinski, Matt; Parnell, Rod; Kohl, Keith; Topping, David J.

    2007-01-01

    This report presents stage-discharge relations for 47 discrete locations along the Colorado River, downstream from Glen Canyon Dam. Predicting the river stage that results from changes in flow regime is important for many studies investigating the effects of dam operations on resources in and along the Colorado River. The empirically based stage-discharge relations were developed from water-surface elevation data surveyed at known discharges at all 47 locations. The rating curves accurately predict stage at each location for discharges between 141 cubic meters per second and 1,274 cubic meters per second. The coefficient of determination (R2) of the fit to the data ranged from 0.993 to 1.00. Given the various contributing errors to the method, a conservative error estimate of ?0.05 m was assigned to the rating curves.

  10. Mean Transit Time as a Predictor of Groundwater Discharge Response in the Upper Colorado River Basin

    NASA Astrophysics Data System (ADS)

    Solder, J. E.; Heilweil, V. M.; Stolp, B. J.; Susong, D.

    2015-12-01

    The Colorado River and its tributaries support 40 million municipal water users and 5.5 million acres of agriculture in the south western United States (U.S. Bureau of Reclamation, 2012). Recent estimates by Rumsey et al. (2015) suggest that a significant portion (about 50 percent) of surface water flow in the Upper Colorado River Basin (UCRB) is sustained by groundwater discharge to streams. Predicted climate variation (Cook et al., 2015) and increased water demand (U.S. Bureau of Reclamation, 2012) within the UCRB suggest future decreases in groundwater discharge, however transient groundwater responses are not well understood. In this study we calculate groundwater mean transit time (MTT) and transit time distribution (TTD) as predictors of the pattern and timing of groundwater response to hydraulic stress. Samples from nineteen large springs within the UCRB were analyzed for environmental tracers to determine MTT and TTD. The predictive value of the MTT is examined by a statistical analysis of MTT, historical spring discharge records, and the Palmer Hydrological Drought Index. MTTs of the 19 springs range from 10 to 15,000 years with a flow-weighted average of 1,650 years. The composite TTD of the 19 springs suggest that flowpaths representing 45 percent of their combined discharge have transit times greater than 100 years. However, spring discharge records indicate that flow responds to drought on much shorter (0.5 - 6 year) time scales, indicative of a hydraulic pressure response. Springs with shorter MTTs (< 100) generally correlated with larger discharge variations and faster responses to drought indicating MTT can be used for estimating the relative magnitude and timing of groundwater response. Previous study (e.g., Manga, 1999) has shown groundwater responds on shorter time scales than the MTT, but of interest the results presented here indicate that relatively stable and old springs with long MTTs (> 100) also show a hydraulic pressure response. While

  11. Is sinuosity a function of slope and bankfull discharge? - A case study of the meandering rivers in the Pannonian Basin

    NASA Astrophysics Data System (ADS)

    Petrovszki, J.; Timár, G.; Molnár, G.

    2014-11-01

    Pre-regulation channel sinuosities of the meandering rivers of the Pannonian Basin are analysed in order to define a mathematical model to estimate the influence of the bankfull discharge and the channel slope on them. As a primary database, data triplets of slope, discharge and sinuosity values were extracted from historical and modern datasets and pre-regulation historical topographic maps. Channel slope values were systematically modified to estimate figures valid before the river regulation works. The bankfull discharges were estimated from the average discharges using a robust yet complex method. The "classical" graphs of Leopold and Wolman (1957), Ackers and Charlton (1970b) and Schumm and Khan (1972) were compiled to a set up a theoretical surface, whose parameters are estimated by the real values of the above database, containing characteristics of the Pannonian Basin rivers. As a result it occurred that there is a two-dimensional function of the bankfull discharges, which provides a good estimation of the most probable sinuosity values of the rivers with the given slope and discharge characteristics. The average RMS error of this estimation is around 15% on this dataset and believed to be the effect of the non-analysed changes in the sediment discharge and size distribution.

  12. Robust multiscale prediction of Po River discharge using a twofold AR-NN approach

    NASA Astrophysics Data System (ADS)

    Alessio, Silvia; Taricco, Carla; Rubinetti, Sara; Zanchettin, Davide; Rubino, Angelo; Mancuso, Salvatore

    2017-04-01

    The Mediterranean area is among the regions most exposed to hydroclimatic changes, with a likely increase of frequency and duration of droughts in the last decades and potentially substantial future drying according to climate projections. However, significant decadal variability is often superposed or even dominates these long-term hydrological trend as observed, for instance, in North Italian precipitation and river discharge records. The capability to accurately predict such decadal changes is, therefore, of utmost environmental and social importance. In order to forecast short and noisy hydroclimatic time series, we apply a twofold statistical approach that we improved with respect to previous works [1]. Our prediction strategy consists in the application of two independent methods that use autoregressive models and feed-forward neural networks. Since all prediction methods work better on clean signals, the predictions are not performed directly on the series, but rather on each significant variability components extracted with Singular Spectrum Analysis (SSA). In this contribution, we will illustrate the multiscale prediction approach and its application to the case of decadal prediction of annual-average Po River discharges (Italy). The discharge record is available for the last 209 years and allows to work with both interannual and decadal time-scale components. Fifteen-year forecasts obtained with both methods robustly indicate a prominent dry period in the second half of the 2020s. We will discuss advantages and limitations of the proposed statistical approach in the light of the current capabilities of decadal climate prediction systems based on numerical climate models, toward an integrated dynamical and statistical approach for the interannual-to-decadal prediction of hydroclimate variability in medium-size river basins. [1] Alessio et. al., Natural variability and anthropogenic effects in a Central Mediterranean core, Clim. of the Past, 8, 831

  13. Erosion, sediment discharge, and channel morphology in the Upper Chattahoochee River basin, Georgia

    USGS Publications Warehouse

    Faye, Robert E.; Carey, W.R.; Stamer, J.K.; Kleckner, R.L.

    1978-01-01

    Average annual rates of sheet erosion and sediment discharge were computed for several watersheds in the Upper Chattahoochee River basin in Georgia. Erosion yields ranged from about 900 to 6,000 tons per year per square mile in nine watersheds and were greatest where land use is largely agricultural or transitional. Suspended sediment yields from the same watershed ranged from about 300 to 800 tons per year per square mile and were greatest from urban areas and least from mostly forested watersheds. The impact of suspended sediment on stream quality was evaluated for 14 watersheds. In general, 60 percent or more of the total annual discharge of trace metals and phosphorus was contributed by suspended sediment. Yields of trace metals and nutrients in suspension were consistently greater in urban watersheds. Turbidity in basin streams increased geometrically with increasing concentrations of suspended sediment. (Woodard-USGS)

  14. A decrease in discharge-normalized DOC export by the Yukon River during summer through autumn

    USGS Publications Warehouse

    Striegl, R.G.; Aiken, G.R.; Dornblaser, M.M.; Raymond, P.A.; Wickland, K.P.

    2005-01-01

    Climate warming is having a dramatic effect on the vegetation distribution and carbon cycling of terrestrial subarctic and arctic ecosystems. Here, we present hydrologic evidence that warming is also affecting the export of dissolved organic carbon and bicarbonate (DOC and HCO3-) at the large basin scale. In the 831,400 km2 Yukon River basin, water discharge (Q) corrected DOC export significantly decreased during the growing season from 1978-80 to 2001-03, indicating a major shift in terrestrial to aquatic C transfer. We conclude that decreased DOC export, relative to total summer through autumn Q, results from increased flow path, residence time, and microbial mineralization of DOC in the soil active layer and groundwater. Counter to current predictions, we argue that continued warming could result in decreased DOC export to the Bering Sea and Arctic Ocean by major subarctic and arctic rivers, due to increased respiration of organic C on land. Copyright 2005 by the American Geophysical Union.

  15. Fate of river Tiber discharge investigated through numerical simulation and satellite monitoring

    NASA Astrophysics Data System (ADS)

    Inghilesi, R.; Ottolenghi, L.; Orasi, A.; Pizzi, C.; Bignami, F.; Santoleri, R.

    2012-04-01

    The aim of this study was to determine the dispersion of passive pollutants associated with the Tiber discharge into the Tyrrhenian Sea using numerical marine dispersion models and satellite data. Numerical results obtained in the simulation of realistic discharge episodes were compared with the corresponding evolution of the spatial distributions of MODIS diffuse light attenuation coefficient at 490 nm (K490), and the results were discussed with reference to the local climate and the seasonal sub-regional circulation regime. The numerical model used for the simulation of the sub-tidal circulation was a Mediterranean sub-regional scale implementation of the Princeton Ocean Model (POM), nested in the large-scale Mediterranean Forecasting System. The nesting method enabled the model to be applied to almost every area in the Mediterranean Sea and also to be used in seasons for which imposing climatological boundary conditions would have been questionable. Dynamical effects on coastal circulation and on water density due to the Tiber discharge were additionally accounted for in the oceanographic model by implementing the river estuary as a point source of a buoyant jet. A Lagrangian particle dispersion model fed with the POM current fields was then run, in order to reproduce the effect of the turbulent transport of passive tracers mixed in the plume with the coastal flow. Two significant episodes of river discharge in both Winter and Summer conditions were discussed in this paper. It was found that the Winter regime was characterized by the presence of a strong coastal jet flowing with the ambient current. In Summer the prevailing wind regime induces coastal downwelling conditions, which tend to confine the riverine waters close to the shore. In such conditions sudden wind reversals due to local weather perturbations, causing strong local upwelling, proved to be an effective way to disperse the tracers offshore, moving the plume from the coast and detaching large pools

  16. Fate of river Tiber discharge investigated through numerical simulation and satellite monitoring

    NASA Astrophysics Data System (ADS)

    Inghilesi, R.; Ottolenghi, L.; Orasi, A.; Pizzi, C.; Bignami, F.; Santoleri, R.

    2012-09-01

    The aim of this study was to determine the dispersion of passive pollutants associated with the Tiber discharge into the Tyrrhenian Sea using numerical marine dispersion models and satellite data. Numerical results obtained in the simulation of realistic discharge episodes were compared with the corresponding evolution of the spatial distributions of MODIS diffuse light attenuation coefficient at 490 nm (K490), and the results were discussed with reference to the local climate and the seasonal sub-regional circulation regime. The numerical model used for the simulation of the sub-tidal circulation was a Mediterranean sub-regional scale implementation of the Princeton Ocean Model (POM), nested in the large-scale Mediterranean Forecasting System. The nesting method enabled the model to be applied to almost every area in the Mediterranean Sea and also to be used in seasons for which imposing climatological boundary conditions would have been questionable. Dynamical effects on coastal circulation and on water density due to the Tiber discharge were additionally accounted for in the oceanographic model by implementing the river estuary as a point source of a buoyant jet. A Lagrangian particle dispersion model fed with the POM current fields was then run in order to reproduce the effect of the turbulent transport of passive tracers mixed in the plume with the coastal flow. Two significant episodes of river discharge in both winter and summer conditions were discussed in this paper. It was found that the winter regime was characterized by the presence of a strong coastal jet flowing with the ambient current. In summer the prevailing wind regime induced coastal downwelling conditions, which tended to confine the riverine waters close to the shore. In such conditions sudden wind reversals due to local weather perturbations, causing moderate local upwelling, proved to be the only effective way to disperse the tracers offshore, moving the plume from the coast and detaching

  17. Feeding bionomics of juvenile chinook salmon relative to thermal discharges in the central Columbia River

    SciTech Connect

    Becker, C.D.

    1994-10-01

    Juvenile chinook salmon (Oncorhynchus tshawytscha) in the Hanford environs of the central Columbia River, Washington consumed almost entirely adult and larval stages of aquatic insects. The food organisms were dominated by midges (Diptera: Tendipedidae); by numbers, adult midges provided 64 and 58% of the diet and larval midges 17 and 18% of the diet, in 1968 and 1969, respectively. The families Hydropsychidae (Trichoptera), Notonectidae (Hemiptera) and Hypogastruridae (Collembola) were of secondary importance. Small fry fed almost exclusively on the small tendipedids. Over 95% of all food organisms originated within the river ecosystem. The distinctive features of food and feeding activity were fourfold: first, relatively few insect groups were utilized; second, the fish depended on drifting, floating, or swimming organisms; third, they visually selected living prey moving in or on the water; and fourth, they were habitat opportunists to a high degree. The 1969 data, were studied to reveal possible thermal effects of heated discharges from plutonium production reactors at Hanford on food and growth parameters. All data were characterized by considerable variation between and within stations. No discernable effects between coldwater and warmwater stations were revealed by analyses of: (1) groups of food organisms utilized, (2) food and feeding activity, (3) numbers of insects consumed, (4) seasonal increases in fish length, (5) fish length-weight relationships, (6) fish coefficients of condition, and (7) stomach biomass. The lack of detectable thermal effects was apparently due to the fact that the main effluent plumes discharge in midstream and the effluents are well mixed before reaching inshore feeding areas. The transient nature of fish groups at each station, influenced by changes in regulated river flows, and the availability of food organisms in the river drift were ecological factors affecting critical thermal evaluation in situ.

  18. Assessment of Coal Geology, Resources, and Reserves in the Gillette Coalfield, Powder River Basin, Wyoming

    USGS Publications Warehouse

    Luppens, James A.; Scott, David C.; Haacke, Jon E.; Osmonson, Lee M.; Rohrbacher, Timothy J.; Ellis, Margaret S.

    2008-01-01

    The Gillette coalfield, within the Powder River Basin in east-central Wyoming, is the most prolific coalfield in the United States. In 2006, production from the coalfield totaled over 431 million short tons of coal, which represented over 37 percent of the Nation's total yearly production. The Anderson and Canyon coal beds in the Gillette coalfield contain some of the largest deposits of low-sulfur subbituminous coal in the world. By utilizing the abundance of new data from recent coalbed methane development in the Powder River Basin, this study represents the most comprehensive evaluation of coal resources and reserves in the Gillette coalfield to date. Eleven coal beds were evaluated to determine the in-place coal resources. Six of the eleven coal beds were evaluated for reserve potential given current technology, economic factors, and restrictions to mining. These restrictions included the presence of railroads, a Federal interstate highway, cities, a gas plant, and alluvial valley floors. Other restrictions, such as thickness of overburden, thickness of coal beds, and areas of burned coal were also considered. The total original coal resource in the Gillette coalfield for all eleven coal beds assessed, and no restrictions applied, was calculated to be 201 billion short tons. Available coal resources, which are part of the original coal resource that is accessible for potential mine development after subtracting all restrictions, are about 164 billion short tons (81 percent of the original coal resource). Recoverable coal, which is the portion of available coal remaining after subtracting mining and processing losses, was determined for a stripping ratio of 10:1 or less. After mining and processing losses were subtracted, a total of 77 billion short tons of coal were calculated (48 percent of the original coal resource). Coal reserves are the portion of the recoverable coal that can be mined, processed, and marketed at a profit at the time of the economic

  19. Anatomy and dynamics of a floodplain, Powder River, Montana, U.S.A.

    USGS Publications Warehouse

    Pizzuto, J.E.; Moody, J.A.; Meade, R.H.

    2008-01-01

    Centimeter-scale measurements on several Powder River floodplains provide insights into the nature of overbank depositional processes that created the floodplains; during a 20-year period after a major flood in 1978. Rising stages initially entered across a sill at the downriver end of the floodplains. Later, as stages continued to rise, water entered the floodplains through distinct low saddles along natural levees. The annual maximum depth of water over the levee crest averaged 0.19 in from 1983 through 1996, and the estimated flow velocities were approximately 0.15 m s-1. Water ponded in the floodplain trough, a topographic low between the natural levee and the pre-flood riverbank, and mud settled as thin layers of nearly constant thickness. Mud layers alternated with sand layers, which were relatively thick near the channel. Together, these beds created a distinctive natural levee. In some locations, individual flood deposits began as a thin mud layer that gradually coarsened upwards to medium-grained sand. Coarsening-upwards sequences form initially as mud because only the uppermost layers of water in the channel supply the first overbank flows, which are rich in mud but starved of sand. At successively higher stages, fine sands and then medium sands increase in concentration in the floodwater and are deposited as fine- and medium-sand layers overlying the initial mud layer. Theoretical predictions from mathematical models of sediment transport by advection and diffusion indicate that these processes acting alone are unlikely to create the observed sand layers of nearly uniform thickness that extend across much of the floodplain. We infer that other transport processes, notably bedload transport, must be important along Powder River. Even with the centimeter-scale measurements of floodplain deposits, daily hydraulic data, and precise annual surface topographic surveys, we were unable to determine any clear correspondence between the gauged flow record of

  20. Past and future changes in the discharges of the Euphrates and Tigris Rivers

    NASA Astrophysics Data System (ADS)

    Lutfi Sen, Omer; Unal, Alper; Kindap, Tayfun; Bozkurt, Deniz; Nuzhet Dalfes, Hasan; Karaca, Mehmet

    2010-05-01

    Temperature has been traditionally used as the primary parameter in detecting the climate change signal at scales from local to global. As being point measurements, however, temperature data come with important shortcomings such as the lack of the representivity of large areas and contamination by urban heat island effect as most stations are located in cities. The snowfed river discharge data, on the other hand, provide an opportunity to detect the climate change signal over large areas that are relatively free of human interference. One of the best quantitative indicators for this purpose is the shift in the median of the cumulative flow, which is commonly referred as center time approach. The present study deploys this approach to investigate the past climate change signals in the Euphrates and Tigris, two important rivers in the Middle East. Streamflow observations on their unregulated tributaries in the eastern Anatolia indicate that the fractions of the discharge between March and June amount to 58-79%, which is a good indication of the fact that these rivers are primarily fed by snowmelt runoff. The statistical analysis reveals that there are no significant trends in the annual streamflow data (i.e., covering 35 years from 1972 to 2006). Differences in the center times of the two consecutive 17-year periods are found to be statistically significant, both with parametric and non-parametric statistical tests, at six out of eight stations at a significance level of 0.1. Among significant stations, the average shift to earlier times is 5.2 days, indicating earlier spring melting of snow due to increased temperatures. The climate change projections based on SRES A2 scenarios indicate up to 6oC warming by the end of 21st century for these basins. This warming implies a decline in the winter snowpack of the region as a result of two processes: increased snowmelt and increased fraction of the precipitation falling in the form of rain. These result in increased

  1. Suspended-sediment and fresh-water discharges in the Ob and Yenisey rivers, 1960-1988

    USGS Publications Warehouse

    Meade, R.H.; Bobrovitskaya, N.N.; Babkin, V.I.

    2000-01-01

    Of the world's great rivers, the Ob and Yenisey rank among the largest suppliers of fresh water and among the smallest suppliers of suspended sediment to the coastal ocean. Sediment in the middle reaches of the rivers is mobilized from bordering terraces and exchanged between channels and flood plains. Sediment in the lower reaches of these great rivers is deposited and stored (permanently, on a millennial time scale) in flood plains. Sediment discharges, already small under natural conditions, are diminished further by large manmade reservoirs that trap significant proportions of the moving solids. The long winter freeze and sudden spring breakup impose a peakedness in seasonal water runoff and sediment discharge that contrasts markedly with that in rivers of the tropics and more temperate climates. Very little sediment from the Ob and Yenisey rivers is being transported to the open waters of the Arctic Ocean under present conditions.

  2. Remote Estimation of Greenland Ice Sheet Supraglacial River Discharge using GIS Modeling and WorldView-2 Satellite Imagery

    NASA Astrophysics Data System (ADS)

    Chu, V. W.; Smith, L. C.; Yang, K.; Gleason, C. J.; Rennermalm, A. K.; Pitcher, L. H.; Legleiter, C. J.; Forster, R. R.

    2014-12-01

    Increasing surface melting on the Greenland ice sheet and rising sea level have heightened the need for understanding the complex pathways transporting meltwater from the ice sheet surface to the ice edge and the ocean. Satellite images show supraglacial rivers abundantly covering the western ablation zone throughout the melt season, transporting large volumes of meltwater into moulins and to the ice edge, yet these rivers remain poorly studied. Here, a GIS modeling framework is developed to estimate supraglacial river discharge by spatially adapting Manning's equation for use with remotely sensed imagery and is applied to supraglacial rivers on the Greenland Ice Sheet. This framework incorporates high-resolution visible/near-infrared WorldView-2 (WV2) satellite imagery, the Greenland Ice Mapping Project (GIMP) DEM, and a field-calibrated WV2 river bathymetry retrieval algorithm and channel roughness parameter. Orthogonal cross-sections are simulated along river centerlines to extract cross-sectional discharge using Manning's equation for open channel flow. A total of 1,629,502 reach-averaged points were retrieved over 465 river networks of western Greenland in 2012, including attributes of width, depth, velocity, slope, wetted perimeter, hydraulic radius, and discharge. This work provides a method for producing spatially extensive, high-resolution estimates of supraglacial meltwater flux in river networks and into the ice sheet.

  3. Interpolating Stage-Discharge Relationships using Serial LiDAR along the Sandy River, Oregon

    NASA Astrophysics Data System (ADS)

    Madin, I.; English, J. T.

    2012-12-01

    Estimating discharge and flood stage along streams is a common and sometimes arduous process for emergency managers and researchers. In most cases this process includes hydrologic and hydraulic modeling to accurately depict inundation in order to examine the height of a particular flow. This study examines the use of multiple lidar data sets along the Sandy River, Oregon to establish relationships between water surface elevations, discharge, and stage height in order to accurately estimate flows without the use of complex models. Airborne lidar elevation data were collected along the Sandy River in 2006, 2007, 2008, and 2011. All of these data sets contain water elevations at USGS gauge station 14142500 Sandy River below Bull Run River near Bull Run, Oregon. Real time data from this station provides accurate stage heights and discharge values. This data serves as calibration for water surface elevations extracted from lidar allowing for a linear relationship between the gauge and lidar elevations to be established for each year's lidar derived water surface. A linear regression analysis of this data allows for researchers to predict flow and stage by querying lidar elevations along the channel. This analysis establishes estimated flows through simply input of elevations queried along the banks of the Sandy River. For geologists, this is an efficient method for estimating flows associated with known water marks of historic floods without going through complex modeling processes. In addition to geologic flows, this method allows emergency managers to quickly determine the discharge of potential flood scenarios based solely on lidar elevations. Results of such an analysis are most accurate at the site of the gauge station, but could be expanded upstream and downstream using known base flood elevations as the denominator in a ratio analysis. This study examines the relationship between lidar elevation data and stage discharge relationship with the goal of predicting

  4. Depositional environments and petrology of the Felix coal interval (Eocene), Powder River Basin, Wyoming

    SciTech Connect

    Warwick, P.D.

    1985-01-01

    A study of a 250 ft. stratigraphic interval that includes the Eocene-age Felix coal of the Wasatch Formation was undertaken in the Powder River Basin of Wyoming to establish a depositional model based on the interrelations of coal-seam geometry, coal maceral composition, and spatial distribution of adjoining rocks. Regional cross sections and maps of major rock bodies were prepared from 147 measured stratigraphic sections and 56 geophysical logs. Trends in maceral and chemical properties within the Felix coal were identified from petrographic and geochemical analyses of 72 coal channel samples. The combined data sets indicate that the thickest portions of the coal are underlain by widespread, interconnected, sandstone-dominated fining-upward sequences whereas areas of thin or split coal are underlain by stacked predominantly fine grained, coarsening-upward sequences. Above the coal, fining-upward sequences are concentrated over thin coal areas and widespread coarsening-upward sequences overlie thick coal areas. The deposits below the Felix resulted from north-northwest flowing meandering rivers. The base and split portions of the seam are the remains of predominantly coniferous trees that grew within a nutrient-rich environment, and the duller central and upper portions of the seam indicate oxidation associated with a raised peat deposit. Ash falls and fires during late stages of peat accumulation may have contributed to the demise of the swamp. After vegetation died large lakes formed and were subsequently filled by crevasse deposits from streams. The final phase of compaction of the fine-grained lake sediments and the thick underlying peat attracted anastomosed alluvial channels.

  5. Remote Estimation of River Discharge and Bathymetry: Sensitivity to Turbulent Dissipation and Bottom Friction

    NASA Astrophysics Data System (ADS)

    Simeonov, J.; Holland, K. T.

    2016-12-01

    We investigated the fidelity of a hierarchy of inverse models that estimate river bathymetry and discharge using measurements of surface currents and water surface elevation. Our most comprehensive depth inversion was based on the Shiono and Knight (1991) model that considers the depth-averaged along-channel momentum balance between the downstream pressure gradient due to gravity, the bottom drag and the lateral stresses induced by turbulence. The discharge was determined by minimizing the difference between the predicted and the measured streamwise variation of the total head. The bottom friction coefficient was assumed to be known or determined by alternative means. We also considered simplifications of the comprehensive inversion model that exclude the lateral mixing term from the momentum balance and assessed the effect of neglecting this term on the depth and discharge estimates for idealized in-bank flow in symmetric trapezoidal channels with width/depth ratio of 40 and different side-wall slopes. For these simple gravity-friction models, we used two different bottom friction parameterizations - a constant Darcy-Weisbach local friction and a depth-dependent friction related to the local depth and a constant Manning (roughness) coefficient. Our results indicated that the Manning gravity-friction model provides accurate estimates of the depth and the discharge that are within 1% of the assumed values for channels with side-wall slopes between 1/2 and 1/17. On the other hand, the constant Darcy-Weisbach friction model underpredicted the true depth and discharge by 7% and 9%, respectively, for the channel with side-wall slope of 1/17. These idealized modeling results suggest that a depth-dependent parameterization of the bottom friction is important for accurate inversion of depth and discharge and that the lateral turbulent mixing is not important. We also tested the comprehensive and the simplified inversion models for the Kootenai River near Bonners Ferry

  6. Trends in major-ion constituents and properties for selected sampling sites in the Tongue and Powder River watersheds, Montana and Wyoming, based on data collected during water years 1980-2010

    USGS Publications Warehouse

    Sando, Steven K.; Vecchia, Aldo V.; Barnhart, Elliott P.; Sando, Thomas R.; Clark, Melanie L.; Lorenz, David L.

    2014-01-01

    The primary purpose of this report is to present information relating to flow-adjusted temporal trends in major-ion constituents and properties for 16 sampling sites in the Tongue and Powder River watersheds based on data collected during 1980–2010. In association with this primary purpose, the report presents background information on major-ion characteristics (including specific conductance, calcium, magnesium, potassium, sodium adsorption ratio, sodium, alkalinity, chloride, fluoride, dissolved sulfate, and dissolved solids) of the sampling sites and coal-bed methane (CBM) produced water (groundwater pumped from coal seams) in the site watersheds, trend analysis methods, streamflow conditions, and factors that affect trend results. The Tongue and Powder River watersheds overlie the Powder River structural basin (PRB) in northeastern Wyoming and southeastern Montana. Limited extraction of coal-bed methane (CBM) from the PRB began in the early 1990’s, and increased dramatically during the late 1990’s and early 2000’s. CBM-extraction activities produce discharges of water with high concentrations of dissolved solids (particularly sodium and bicarbonate ions) relative to most stream water in the Tongue and Powder River watersheds. Water-quality of CBM produced water is of concern because of potential effects of sodium on agricultural soils and potential effects of bicarbonate on aquatic biota. Two parametric trend-analysis methods were used in this study: the time-series model (TSM) and ordinary least squares regression (OLS) on time, streamflow, and season. The TSM was used to analyze trends for 11 of the 16 study sites. For five sites, data requirements of the TSM were not met and OLS was used to analyze trends. Two primary 10-year trend-analysis periods were selected. Trend-analysis period 1 (water years 1986–95; hereinafter referred to as period 1) was selected to represent variability in major-ion concentrations in the Tongue and Powder River

  7. Short-term variability in particle flux: Storms, blooms and river discharge in a coastal sea

    NASA Astrophysics Data System (ADS)

    Johannessen, Sophia C.; Macdonald, Robie W.; Wright, Cynthia A.; Spear, David J.

    2017-07-01

    The flux and composition of particles sinking in the surface ocean vary on a wide range of time scales. This variability is a component of underwater weather that is analogous to rain. The rain of particles in the coastal ocean is affected by atmospheric events, such as rainstorms and windstorms; by events on land, such as peaks in river discharge or coastal erosion; and by events within the surface ocean, such as phytoplankton blooms. Here, we use a four-year record of sinking particles collected using sediment traps moored at 50 m depth at two locations in the Strait of Georgia, a coastal sea off the west coast of Canada, to determine the relative importance of short-term events to particle flux. We identify four dominant types of particle-flux events: those associated with 1) summer freshet of the Fraser River, 2) rainstorms, 3) phytoplankton blooms, and 4) a jellyfish bloom. The relative importance of these events differs between the southern Strait, where the Fraser River freshet dominates flux and variability, and the northern Strait, where the effects of phytoplankton blooms, rainstorms and small local rivers are more evident. During 2008-2012, half of each year's total flux accumulated over 10-26% of the year in the southern Strait, mainly during the Fraser River freshet. In the northern Strait half of the annual flux accumulated over 22-36% of the year, distributed among small events during spring to fall. The composition of the sinking particulate matter also varied widely, with organic carbon and biogenic silica ranging over 0.70-5.7% (excluding one event) and 0.4-14%, respectively, in the south, compared with 0.17-22% and 0.31-33% in the north. Windstorms had no immediate effect on particle flux in either basin. A large phytoplankton bloom in April 2011, in the northern Strait contributed 25% of the year's organic carbon at that site and 53% of the biogenic silica. A jellyfish bloom in July 2008 contributed 16% of the year's nitrogen and 12% of the year

  8. Map showing contours on top of the upper Cretaceous Mowry Shale, Powder River basin, Wyoming and Montana

    USGS Publications Warehouse

    Crysdale, B.L.

    1991-01-01

    This map is one in a series of U.S. Geological Survey Miscellaneous Field Studies (MF) maps showing computer-generated structure contours, isopachs, and cross sections of selected formations in the Powder River basin, Wyoming and Montana. The map and cross sections were constructed from information stored in a U.S. Geological Survey Evolution of Sedimentary Basins data base. This data base contains picks of geologic formation and (or) unit tops and bases determined from electric resistivity and gamma-ray logs of 8,592 wells penetrating Tertiary and older rocks in the Powder River basin. Well completion cards (scout tickets) were reviewed and compared with copies of all logs, and formation or unit contacts determined by N. M. Denson, D.L. Macke, R. R. Schumann and others. This isopach map is based on information from 4,926 of these wells that penetrate the Minnelusa Formation and equivalents.

  9. Map showing structure contours on the top of the upper Jurassic Morrison Formation, Powder River basin, Wyoming and Montana

    USGS Publications Warehouse

    Crysdale, B.L.

    1991-01-01

    This map is one in a series of U.S. Geological Survey Miscellaneous Field Studies (MF) maps showing computer-generated structure contours, isopachs, and cross sections of selected formations in the Powder River basin, Wyoming and Montana. The map and cross sections were constructed from information stored in a U.S. Geological Survey Evolution of Sedimentary Basins data base. This data base contains picks of geologic formation and (or) unit tops and bases determined from electric resistivity and gamma-ray logs of 8,592 wells penetrating Tertiary and older rocks in the Powder River basin. Well completion cards (scout tickets) were reviewed and compared with copies of all logs, and formation or unit contacts determined by N. M. Denson, D.L. Macke, R. R. Schumann and others. This isopach map is based on information from 2,429 of these wells that penetrate the Minnelusa Formation and equivalents.

  10. Freshwater discharge into the Caribbean Sea from the rivers of Northwestern South America (Colombia): Magnitude, variability and recent changes

    NASA Astrophysics Data System (ADS)

    Restrepo, Juan Camilo; Ortíz, Juan Carlos; Pierini, Jorge; Schrottke, Kerstin; Maza, Mauro; Otero, Luís; Aguirre, Julián

    2014-02-01

    The monthly averaged freshwater discharge data from ten rivers in northern Colombia (Caribbean alluvial plain) draining into the Caribbean Sea were analysed to quantify the magnitudes, to estimate long-term trends, and to evaluate the variability of discharge patterns. These rivers deliver ∼340.9 km3 yr-1 of freshwater to the Caribbean Sea. The largest freshwater supply is provided by the Magdalena River, with a mean discharge of 205.1 km3 yr-1 at Calamar, which is 26% of the total fluvial discharge into this basin. From 2000 to 2010, the annual streamflow of these rivers increased as high as 65%, and upward trends in statistical significance were found for the Mulatos, Canal del Dique, Magdalena, and Fundación Rivers. The concurrence of major oscillation processes and the maximum power of the 3-7 year band fluctuation defined a period of intense hydrological activity from approximately 1998-2002. The wavelet spectrum highlighted a change in the variability patterns of fluvial systems between 2000 and 2010 characterised by a shift towards a quasi-decadal process (8-12 years) domain. The Intertropical Convergence Zone (ITCZ), El Niño - Southern Oscillation (ENSO) events, and quasi-decadal climate processes are the main factors controlling the fluvial discharge variability of these fluvial systems.

  11. The Past and Future Responses of Salinity in the Delaware Estuary to Sea-level Rise and River Discharge Variability

    NASA Astrophysics Data System (ADS)

    Ross, A.; Najjar, R.; Li, M.

    2016-02-01

    We use a combination of long historical records (1950s-present) and statistical, idealized, and 3D numerical models to explore the response of salinity in the Delaware Estuary to sea-level rise and changing river discharge. Over the historical period, salinity generally shows negligible or downwards trends, mostly as a result of increasing river discharge. However, after removing the influence of river discharge using the observations and a statistical model, there is a positive sea-level rise signal at several locations. The salinity increase as a result of sea-level rise determined by the statistical models closely matches the values simulated by the idealized and 3D numerical models. Under a scenario of 0.55 m of additional sea-level rise, all three models project salinity increases of up to 1.5-2.5 psu. Allowing sea level to rise by 1 meter will increase salinity by about 2.5-4.5 psu. All three models also show that although increasing river discharge has moderated salinity trends in the past, future increases in river discharge are unlikely to be able to offset the salinity increase caused by sea-level rise. In addition, the spatial distribution of these changes and potential consequences for the estuarine ecosystem are discussed.

  12. Evaluation of the satellite-based Global Flood Detection System for measuring river discharge: influence of local factors

    NASA Astrophysics Data System (ADS)

    Revilla-Romero, B.; Thielen, J.; Salamon, P.; De Groeve, T.; Brakenridge, G. R.

    2014-11-01

    One of the main challenges for global hydrological modelling is the limited availability of observational data for calibration and model verification. This is particularly the case for real-time applications. This problem could potentially be overcome if discharge measurements based on satellite data were sufficiently accurate to substitute for ground-based measurements. The aim of this study is to test the potentials and constraints of the remote sensing signal of the Global Flood Detection System for converting the flood detection signal into river discharge values. The study uses data for 322 river measurement locations in Africa, Asia, Europe, North America and South America. Satellite discharge measurements were calibrated for these sites and a validation analysis with in situ discharge was performed. The locations with very good performance will be used in a future project where satellite discharge measurements are obtained on a daily basis to fill the gaps where real-time ground observations are not available. These include several international river locations in Africa: the Niger, Volta and Zambezi rivers. Analysis of the potential factors affecting the satellite signal was based on a classification decision tree (random forest) and showed that mean discharge, climatic region, land cover and upstream catchment area are the dominant variables which determine good or poor performance of the measurement sites. In general terms, higher skill scores were obtained for locations with one or more of the following characteristics: a river width higher than 1km; a large floodplain area and in flooded forest, a potential flooded area greater than 40%; sparse vegetation, croplands or grasslands and closed to open and open forest; leaf area index > 2; tropical climatic area; and without hydraulic infrastructures. Also, locations where river ice cover is seasonally present obtained higher skill scores. This work provides guidance on the best locations and limitations

  13. Evaluation of the satellite-based Global Flood Detection System for measuring river discharge: influence of local factors

    NASA Astrophysics Data System (ADS)

    Revilla-Romero, B.; Thielen, J.; Salamon, P.; De Groeve, T.; Brakenridge, G. R.

    2014-07-01

    One of the main challenges for global hydrological modelling is the limited availability of observational data for calibration and model verification. This is particularly the case for real time applications. This problem could potentially be overcome if discharge measurements based on satellite data were sufficiently accurate to substitute for ground-based measurements. The aim of this study is to test the potentials and constraints of the remote sensing signal of the Global Flood Detection System for converting the flood detection signal into river discharge values. The study uses data for 322 river measurement locations in Africa, Asia, Europe, North America and South America. Satellite discharge measurements were calibrated for these sites and a validation analysis with in situ discharge was performed. The locations with very good performance will be used in a future project where satellite discharge measurements are obtained on a daily basis to fill the gaps where real time ground observations are not available. These include several international river locations in Africa: Niger, Volta and Zambezi rivers. Analysis of the potential factors affecting the satellite signal was based on a classification decision tree (Random Forest) and showed that mean discharge, climatic region, land cover and upstream catchment area are the dominant variables which determine good or poor performance of the measurement sites. In general terms, higher skill scores were obtained for locations with one or more of the following characteristics: a river width higher than 1 km; a large floodplain area and in flooded forest; with a potential flooded area greater than 40%; sparse vegetation, croplands or grasslands and closed to open and open forest; Leaf Area Index > 2; tropical climatic area; and without hydraulic infrastructures. Also, locations where river ice cover is seasonally present obtained higher skill scores. The work provides guidance on the best locations and limitations

  14. Kriging analysis of mean annual precipitation, Powder River Basin, Montana and Wyoming

    USGS Publications Warehouse

    Karlinger, M.R.; Skrivan, James A.

    1981-01-01

    Kriging is a statistical estimation technique for regionalized variables which exhibit an autocorrelation structure. Such structure can be described by a semi-variogram of the observed data. The kriging estimate at any point is a weighted average of the data, where the weights are determined using the semi-variogram and an assumed drift, or lack of drift, in the data. Block, or areal, estimates can also be calculated. The kriging algorithm, based on unbiased and minimum-variance estimates, involves a linear system of equations to calculate the weights. Kriging variances can then be used to give confidence intervals of the resulting estimates. Mean annual precipitation in the Powder River basin, Montana and Wyoming, is an important variable when considering restoration of coal-strip-mining lands of the region. Two kriging analyses involving data at 60 stations were made--one assuming no drift in precipitation, and one a partial quadratic drift simulating orographic effects. Contour maps of estimates of mean annual precipitation were similar for both analyses, as were the corresponding contours of kriging variances. Block estimates of mean annual precipitation were made for two subbasins. Runoff estimates were 1-2 percent of the kriged block estimates. (USGS)

  15. Lithologic variations and diagenesis of Lower Cretaceous Muddy Formation in northern Powder River basin, Wyoming

    SciTech Connect

    Walker, A.L.; Patterson, P.E.

    1986-08-01

    Regional facies studies show that sandstones in the Muddy Formation, northern Powder River basin, were deposited in fluvial and nearshore marine paleoenvironments. Most sandstones of the fluvial facies contain only minor amounts of clay matrix and are classified as quartzarenite or sublitharenite, whereas those of the shoreface facies contain appreciable clay and are classified as litharenite or arkose. The arkoses are concentrated along a narrow belt that trends northeastward, parallel to the inferred paleoshoreline. Both the fluvial and shoreface sandstones have been variably affected by postdepositional alteration. During early stages of diagenesis, matrix clay was formed predominantly within the shoreface sandstones, owing mainly to alteration of volcanic material. Later, quartz overgrowths and calcite cement were precipitated within the remaining pore spaces in both fluvial and shoreface sandstones. Calcite also replaced detrital framework grains and some of the previously formed matrix clay. During intermediate diagenetic stages, detrital feldspar grains, particularly those in the arkosic shoreface sandstones, were replaced by albite, which characteristically lacks twinning or displays distinctive chessboard texture. Microprobe analyses indicate that both forms are essentially pure albite. During later stages of diagenesis, following maximum burial, much of the calcite was dissolved, producing secondary porosity. Inasmuch as the calcite was precipitated early, i.e., prior to significant compaction, and inasmuch as it replaced both framework grains and authigenic matrix clay, the secondary pores exhibit a relatively high level of interconnection. It is this secondary porosity that has contributed to the migration and storage of hydrocarbons in the Muddy Formation.

  16. Climate control on Quaternary coal fires and landscape evolution, Powder River basin, Wyoming and Montana

    SciTech Connect

    Riihimaki, C.A.; Reiners, P.W.; Heffern, E.L.

    2009-03-15

    Late Cenozoic stream incision and basin excavation have strongly influenced the modern Rocky Mountain landscape, but constraints on the timing and rates of erosion are limited. The geology of the Powder River basin provides an unusually good opportunity to address spatial and temporal patterns of stream incision. Numerous coal seams in the Paleocene Fort Union and Eocene Wasatch Formations within the basin have burned during late Cenozoic incision, as coal was exposed to dry and oxygen-rich near-surface conditions. The topography of this region is dominated by hills capped with clinker, sedimentary rocks metamorphosed by burning of underlying coal beds. We use (U-Th)/He ages of clinker to determine times of relatively rapid erosion, with the assumption that coal must be near Earth's surface to burn. Ages of 55 in situ samples range from 0.007 to 1.1 Ma. Clinker preferentially formed during times in which eccentricity of the Earth's orbit was high, times that typically but not always correlate with interglacial periods. Our data therefore suggest that rates of landscape evolution in this region are affected by climate fluctuations. Because the clinker ages correlate better with eccentricity time series than with an oxygen isotope record of global ice volume, we hypothesize that variations in solar insolation modulated by eccentricity have a larger impact on rates of landscape evolution in this region than do glacial-interglacial cycles.

  17. Status Report: USGS coal assessment of the Powder River Basin, Wyoming

    SciTech Connect

    James A. Luppens; Timothy J. Rohrbacher; Jon E. Haacke; David C. Scott; Lee M. Osmonson

    2006-07-01

    This publication reports on the status of the current coal assessment of the Powder River Basin (PRB) in Wyoming and Montana. This slide program was presented at the Energy Information Agency's 2006 EIA Energy Outlook and Modeling Conference in Washington, DC, on March 27, 2006. The PRB coal assessment will be the first USGS coal assessment to include estimates of both regional coal resources and reserves for an entire coal basin. Extensive CBM and additional oil and gas development, especially in the Gillette coal field, have provided an unprecedented amount of down-hole geological data. Approximately 10,000 new data points have been added to the PRB database since the last assessment (2002) which will provide a more robust evaluation of the single most productive U.S. coal basin. The Gillette coal field assessment, including the mining economic evaluation, is planned for completion by the end of 2006. The geologic portion of the coal assessment work will shift to the northern and northwestern portions of the PRB before the end of 2006 while the Gillette engineering studies are finalized. 7 refs.

  18. Regional hydrocarbon generation, migration, and accumulation pattern of Cretaceous strata, Powder River Basin

    SciTech Connect

    Meissner, F.F.

    1985-05-01

    A cell of abnormally high fluid pressure in the deep part of the Powder River basin is centered in an area where oil-generation-prone source rocks in the Skull Creek (oldest), Mowry, and Niobrara (youngest) formations are presently at their maximum hydrocarbon-volume generation rate. The overpressures are believed to be caused by the high conversion rate of solid kerogen in the source rocks to an increased volume of potentially expellable fluid hydrocarbons. In this area, hydrocarbons appear to be the principal mobile fluid species present in reservoirs within or proximal to the actively generating source rocks. Maximum generation pressures within the source rocks have caused vertical expulsion through a pressure-induced microfracture system and have charged the first available underlying and/or overlying sandstone carrier-reservoir bed. Hydrocarbons generated in the Skull Creek have been expelled downward into the Dakota Sandstone and upward into the Muddy Sandstone. Hydrocarbons generated in the Mowry have been expelled downward into the Muddy or upward into lower Frontier sandstones. Hydrocarbons generated in the Niobrara have been expelled downward into upper Frontier sandstones or upward into the first available overlying sandstone in the Upper Cretaceous. The first chargeable sandstone overlying the Niobrara, in ascending order, may be the (1) Shannon, (2) Sussex, (3) Parkman, (4) Teapot, or (5) Tekla, depending on the east limit of each sandstone with respect to vertical fracture migration through the Cody Shale from the underlying area of mature overpressured Niobrara source rocks.

  19. Fault control of channel sandstones in Dakota Formation, southwest Powder River basin, Wyoming

    SciTech Connect

    Moore, W.R.

    1983-08-01

    The Dakota Formation is an important oil reservoir in the southwestern Powder River basin and adjoining Casper arch. Two fields, Burke Ranch and South Cole Creek, are used as examples to show the depositional environments of the Dakota and to indicate the influence of tectonic control on the distribution of the environments. Burke Ranch field is a stratigraphic trap which produces oil from the upper bench of the Dakota. The environment of deposition of the reservoir, determined by subsurface analysis, is a channel sandstone. South Cole Creek field is a structural-stratigraphic trap which produces from the lower bench of the Dakota. Two distinct facies, a channel and channel margin sandstone, exist at South Cole Creek. At both Burke Ranch and South Cole Creek it can be shown that the Dakota channels were deposited on the downthrown side of faults, which were present during Dakota time and which now are reflected on the surface by drainage patterns. An understanding of the environments of deposition of the Dakota and control of the environments by paleotectonics is necessary for exploration for these prolific reservoirs.

  20. Regional tectonic influence on Early Cretaceous depositional patterns in Powder River basin, Wyoming and Montana

    SciTech Connect

    Bryan, J.G.; Petta, T.J.

    1988-01-01

    Integration of gravity, magnetic, seismic, and subsurface data from the Powder River basin indicates left-lateral wrenching caused principal and secondary shear compression to develop along northwest and east trends, respectively. This well-documented strain fabric caused by Laramide events has affected basin morphology and depositional patterns within the basin since the Early Cretaceous. Regional lineaments mapped at the surface have vertical displacements of tens of feet. These slightly displaced features can be correlated with wrench-related synthetic and antithetic fractures that display miles of subsurface lateral displacement. Results of detailed integrated forward modeling indicate these fractured zones had a significant effect on the distribution of Lower Cretaceous reservoir sands. Case histories from Buck Draw (Dakota Formation) and Bell Creek (Muddy Sandstone) fields illustrate how the consideration of basement tectonic influence is important to the proper evaluation of exploration leads. Proper use of all available data is essential to the reduction of exploratory risk and can aid in planning offset locations.

  1. The production of a premium solid fuel from Powder River Basin coal

    SciTech Connect

    Merriam, N.; Sethi, V.; Thomas, K.; Grimes, R.W.

    1992-09-01

    This report describes our initial evaluation of a process designed to produce premium-quality solid fuel from Powder River Basin (PRB) coal. The process is based upon our experience gained by producing highly-reactive, high-heating-value char as part of a mild-gasification project. In the process, char containing 20 to 25 wt % volatiles and having a gross heating value of 12,500 to 13,000 Btu/lb is produced. The char is then contacted by coal-derived liquid. The result is a deposit of 6 to 8 wt % pitch on the char particles. The lower boiling component of the coal-derived liquid which is not deposited on the char is burned as fuel. Our economic evaluation shows the process will be economically attractive if the product can be sold for about $20/ton or more. Our preliminary tests show that we can deposit pitch on to the char, and the product is less dusty, less susceptible to readsorption of moisture, and has reduced susceptibility to self heating.

  2. The production of a premium solid fuel from Powder River Basin coal. [COMPCOAL Process

    SciTech Connect

    Merriam, N.; Sethi, V.; Thomas, K.; Grimes, R.W.

    1992-01-01

    This report describes our initial evaluation of a process designed to produce premium-quality solid fuel from Powder River Basin (PRB) coal. The process is based upon our experience gained by producing highly-reactive, high-heating-value char as part of a mild-gasification project. In the process, char containing 20 to 25 wt % volatiles and having a gross heating value of 12,500 to 13,000 Btu/lb is produced. The char is then contacted by coal-derived liquid. The result is a deposit of 6 to 8 wt % pitch on the char particles. The lower boiling component of the coal-derived liquid which is not deposited on the char is burned as fuel. Our economic evaluation shows the process will be economically attractive if the product can be sold for about $20/ton or more. Our preliminary tests show that we can deposit pitch on to the char, and the product is less dusty, less susceptible to readsorption of moisture, and has reduced susceptibility to self heating.

  3. Blending Powder River Basin coals to meet clean air compliance requirements

    SciTech Connect

    Meehan, S.W.; Mehta, A.K.

    1995-03-01

    Many utilities are considering blending their higher sulfur bituminous coals with lower sulfur Powder River Basin (PRB) coals in order to meet clean air compliance requirements. However, the impacts of these coal blends on the performance of equipment and stack emissions are largely uncertain. Utilities need a validated, systematic methodology to: (1) estimate the modifications that may be required to burn these blends in a cost effective, safe and reliable manner, and (2) systematically and meaningfully test burn PRB to derive necessary performance and planning data. PSI Energy has entered into a Tailored Collaboration Agreement with Electric Power Research Institute (EPRI) in order to address these issues through a PRB coal blend test burn program at PSI`s Gibson Station. This is a first of a kind demonstration of PRB:bituminous coal blends on a supercritical unit of the type in service at Gibson. The objective of the program is to evaluate the feasibility of burning the PRB subbituminous coal with midwestern bituminous coals. The project is intended to develop: (1) a methodology for maximizing the utilized PRB blend fraction; (2) a methodology for evaluating the associated physical improvements and operational enhancements required for the plant; and, (3) an assessment of the incremental unit performance impacts. The test burn PRB blend ratio is to be staged from a minimal level to 100 percent in steps of approximately 10 percentage points. The cumulative physical test burn is expected to require twelve months or longer.

  4. Selenium mobilization in a surface coal mine, Powder River Basin, Wyoming, U.S.A.

    USGS Publications Warehouse

    Dreher, G.B.; Finkelman, R.B.

    1992-01-01

    Elevated concentrations (0.6-0.9 mg/l) of selenium were detected in the groundwater of a small backfill area at a surface mine in the Powder River Basin, Wyoming. This report focuses on the source of selenium, its modes of occurrence in overburden deposits and backfill groundwater, and its fate. The immediate source of the selenium appeared to be the dissolution of preexisting soluble salts from the unsaturated zone of the overburden. The ultimate source of selenium was probably the oxidation of selenium-bearing pyrite in the geologic past. Overburden was placed partially in the saturated zone of the backfill where, upon resaturation, soluble salts dissolved in the groundwater. Water standing in the pit at the time of backfilling might have contributed to the elevated concentrations of selenium and other solutes. Selenium was found in an ash-rich coal and in clastic sediments in seven different modes of occurrence. The concentration of soluble selenium in the groundwater at this site has been decreasing since monitoring began in late 1982, and at the present rate of decrease, the concentration should drop below the State of Wyoming guideline of 0.05 mg/l for selenium in water intended for use by livestock by about mid-1992. The decrease in soluble selenium concentration may in part be due to microbially assisted reduction of selenate followed by sorption on clays and other sorbents. ?? 1992 Springer-Verlag New York Inc.

  5. Seismic properties investigation of the Springer Ranch landslide, Powder River basin, Wyoming

    USGS Publications Warehouse

    Miller, C.H.; Ramirez, A.L.; Bullard, T.G.

    1980-01-01

    A recent and rapid increase since the mid-1970's in commercial and residential development in the Powder River Basin, Wyoming and Montana, is caused by exploitation of vast coal and other resources in the basin. One geologic hazard to such development is landsliding. A landslide sufficiently representative of others in the area was chosen for detailed seismic studies. Studies of this landslide show that a low-velocity layer overlies a high-velocity layer both on the slide and away from it and that the contact between the volocity layers is nearly parallel with the preslide topographic surface. Computed shear and other elastic moduli of the low-velocity layer are about one-tenth those of the high-velocity layer. When failure occurs within the slope materials, it will very likely be confined to the low-velocity layer. The number and position of main shear planes in the landslide are unknown, but the main slippage surface is probably near the contact between the low- and high-velocity layers. The main cause of landslide failure in the study area is apparently the addition of moisture to the low-velocity layer.

  6. Estimation of nutrient discharge from the Yangtze River to the East China Sea and the identification of nutrient sources.

    PubMed

    Tong, Yindong; Bu, Xiaoge; Chen, Junyue; Zhou, Feng; Chen, Long; Liu, Maodian; Tan, Xin; Yu, Tao; Zhang, Wei; Mi, Zhaorong; Ma, Lekuan; Wang, Xuejun; Ni, Jing

    2017-01-05

    Based on a time-series dataset and the mass balance method, the contributions of various sources to the nutrient discharges from the Yangtze River to the East China Sea are identified. The results indicate that the nutrient concentrations vary considerably among different sections of the Yangtze River. Non-point sources are an important source of nutrients to the Yangtze River, contributing about 36% and 63% of the nitrogen and phosphorus discharged into the East China Sea, respectively. Nutrient inputs from non-point sources vary among the sections of the Yangtze River, and the contributions of non-point sources increase from upstream to downstream. Considering the rice growing patterns in the Yangtze River Basin, the synchrony of rice tillering and the wet seasons might be an important cause of the high nutrient discharge from the non-point sources. Based on our calculations, a reduction of 0.99Tg per year in total nitrogen discharges from the Yangtze River would be needed to limit the occurrences of harmful algal blooms in the East China Sea to 15 times per year. The extensive construction of sewage treatment plants in urban areas may have only a limited effect on reducing the occurrences of harmful algal blooms in the future. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Discharge Driven Nitrogen Dynamics in a Mesoscale River Basin As Constrained by Stable Isotope Patterns.

    PubMed

    Mueller, Christin; Zink, Matthias; Samaniego, Luis; Krieg, Ronald; Merz, Ralf; Rode, Michael; Knöller, Kay

    2016-09-06

    Nitrate loads and corresponding dual-isotope signatures were used to evaluate large scale N dynamics and trends in a river catchment with a strong anthropogenic gradient (forest conservation areas in mountain regions, and intensive agriculturally used lowlands). The Bode River catchment with an area of 3200 km(2) in the Harz Mountains and central German lowlands was investigated by a two years monitoring program including 133 water sampling points each representing a subcatchment. Based on discharge data either observed or simulated by the mesoscale hydrological model (mHM) a load based interpretation of hydrochemical and isotope data was conducted. Nitrate isotopic signatures in the entire catchment are influenced by (I) the contribution of different nitrogen sources, (II) by variable environmental conditions during the formation of nitrate, and (III) by a minor impact of denitrification. For major tributaries, a relationship between discharge and nitrate isotopic signatures is observed. This may in part be due to the fact, that during periods of higher hydrologic activity a higher wash out of isotopically lighter nitrate formed by bacterial nitrification processes of reduced or organic soil nitrogen occurs. Beyond that, in-stream denitrification seems to be more intense during periods of low flow.

  8. River mixing in the Amazon as a driver of concentration-discharge relationships

    NASA Astrophysics Data System (ADS)

    Moquet, Jean-Sébastien; Bouchez, Julien; Carlo Espinoza, Jhan; Martinez, Jean-Michel; Guyot, Jean-Loup; Lagane, Christelle; Filizola, Naziano; Aniceto, Keila; Noriega, Luis; Hidalgo Sanchez, Liz; Pombosa, Rodrigo; Fraizy, Pascal; Santini, William; Timouk, Franck; Vauchel, Philippe

    2017-04-01

    Large hydrological systems such as continental-scale river basins aggregate water from compositionally different tributaries. Here we explore how such aggregation can affect solute concentration-discharge (C-Q) relationships and thus obscure the message carried by these relationships in terms of weathering properties of the Critical Zone. We compute 10 day-frequency time series of Q and major solute (Si, Ca2+, Mg2+, K+, Na+, Cl-, SO42-) C and fluxes (F) for 13 gauging stations of the SNO-HYBAM Monitoring Program (Geodynamical, hydrological and Biogeochemical control of erosion/weathering and material transport in the Amazon, Orinoco and Congo basins) located throughout the Amazon basin, the largest river basin in the world. Concentration-discharge relationships vary in a systematic manner, shifting for most solutes from a nearly "chemostatic" behavior (constant C) at the Andean mountain front to a more "dilutional" pattern (negative C-Q relationship) towards the system mouth. Associated to this shift in trend is a shift in shape: C-Q hysteresis becomes more prominent at the most downstream stations. A simple model of tributary mixing allows us to identify the important parameters controlling C-Q trends and shapes in the mixture, and we show that for the Amazon case, the model results are in qualitative agreement with the observations. Altogether, this study suggests that mixing of water and solutes between different flowpaths leads to altered C-Q relationships.

  9. Influence of Wastewater Discharge on the Metabolic Potential of the Microbial Community in River Sediments.

    PubMed

    Li, Dong; Sharp, Jonathan O; Drewes, Jörg E

    2016-01-01

    To reveal the variation of microbial community functions during water filtration process in river sediments, which has been utilized widely in natural water treatment systems, this study investigates the influence of municipal wastewater discharge to streams on the phylotype and metabolic potential of the microbiome in upstream and particularly various depths of downstream river sediments. Cluster analyses based on both microbial phylogenetic and functional data collectively revealed that shallow upstream sediments grouped with those from deeper subsurface downstream regions. These sediment samples were distinct from those found in shallow downstream sediments. Functional genes associated with carbohydrate, xenobiotic, and certain amino acid metabolisms were overrepresented in upstream and deep downstream samples. In contrast, the more immediate contact with wastewater discharge in shallow downstream samples resulted in an increase in the relative abundance of genes associated with nitrogen, sulfur, purine and pyrimidine metabolisms, as well as restriction-modification systems. More diverse bacterial phyla were associated with upstream and deep downstream sediments, mainly including Actinobacteria, Planctomycetes, and Firmicutes. In contrast, in shallow downstream sediments, genera affiliated with Betaproteobacteria and Gammaproteobacteria were enriched with putative functions that included ammonia and sulfur oxidation, polyphosphate accumulation, and methylotrophic bacteria. Collectively, these results highlight the enhanced capabilities of microbial communities residing in deeper stream sediments for the transformation of water contaminants and thus provide a foundation for better design of natural water treatment systems to further improve the removal of contaminants.

  10. Characteristics of Lake Chad level variability and links to ENSO, precipitation, and river discharge.

    PubMed

    Okonkwo, Churchill; Demoz, Belay; Gebremariam, Sium

    2014-01-01

    This study used trend, correlation, and wavelet analysis to characterize Lake Chad (LC) level fluctuations, river discharge, El Niño Southern Oscillation (ENSO), and precipitation regimes and their interrelationships. Linear correlation results indicate a negative association between ENSO and LC level, river discharge and precipitation. Trend analysis shows increasing precipitation in the Lake Chad Basin (LCB) but decreasing LC level. The mode of interannual variability in LC level, rainfall, and ENSO analyzed using wavelet analysis is dominated by 3-4-year periods. Results show that variability in ENSO could explain only 31% and 13% of variations in LC level at Kindjeria and precipitation in the northern LCB, respectively. The wavelet transform coherency (WTC) between LC level of the southern pool at Kalom and ENSO is statistically significant at the 95% confidence level and phase-locked, implying a cause-and-effect association. These strong coherencies coincide with the La Niña years with the exception of 1997-1998 El Niño events. The WTC shows strong covariance between increasing precipitation and LC level in the northern pool at a 2- to 4-year band and 3- to 4-year band localized from 1996 to 2010. Implications for water resource planning and management are discussed.

  11. Characteristics of Lake Chad Level Variability and Links to ENSO, Precipitation, and River Discharge

    PubMed Central

    Demoz, Belay; Gebremariam, Sium

    2014-01-01

    This study used trend, correlation, and wavelet analysis to characterize Lake Chad (LC) level fluctuations, river discharge, El Niño Southern Oscillation (ENSO), and precipitation regimes and their interrelationships. Linear correlation results indicate a negative association between ENSO and LC level, river discharge and precipitation. Trend analysis shows increasing precipitation in the Lake Chad Basin (LCB) but decreasing LC level. The mode of interannual variability in LC level, rainfall, and ENSO analyzed using wavelet analysis is dominated by 3-4-year periods. Results show that variability in ENSO could explain only 31% and 13% of variations in LC level at Kindjeria and precipitation in the northern LCB, respectively. The wavelet transform coherency (WTC) between LC level of the southern pool at Kalom and ENSO is statistically significant at the 95% confidence level and phase-locked, implying a cause-and-effect association. These strong coherencies coincide with the La Niña years with the exception of 1997-1998 El Niño events. The WTC shows strong covariance between increasing precipitation and LC level in the northern pool at a 2- to 4-year band and 3- to 4-year band localized from 1996 to 2010. Implications for water resource planning and management are discussed. PMID:25538946

  12. Research of the recast layer on implant surface modified by micro-current electrical discharge machining using deionized water mixed with titanium powder as dielectric solvent

    NASA Astrophysics Data System (ADS)

    Chen, Sung-Long; Lin, Ming-Hong; Huang, Guo-Xin; Wang, Chia-Ching

    2014-08-01

    Surface modification of Ti using micro-current electrical discharge machining (MC-EDM) technology at various working parameters was conducted in the present study. A significant decrease in amount of surface cracks for modified Ti in deionized water mixed with concentration of 3 g/l Ti powder dielectric solvent was determined. Increasing the concentration of Ti powder to 6 g/l, no micro-cracks were observed on the modified Ti surfaces at current 0.1 A for short-pulse durations (≤50 μs). Moreover, the thickness of the recast layer increases with increasing current, pulse duration and concentration. Under the same working parameters, the thickness of recast layers on modified Ti enhances to approximately 4-11 μm in the concentration of 6 g/l Ti powder dielectric solvent. When Ti modified at different working parameters in deionized water mixed with Ti powder dielectric solvent, the TiO phase was observed within the recast layers. It was found that the modified Ti at current 0.1 A for 30 μs and 50 μs in a 6 g/l concentration of Ti powder dielectric solvent generates a hydrophilicity surface. Therefore, adding a suitable concentration of Ti powder into the dielectric solvent not only prevent the formation of surface cracks and micro-cracks, but also raise the wettability on the surfaces of Ti during MC-EDM modifications.

  13. Impacts of Columbia River discharge on salmonid habitat: 1. A nonstationary fluvial tide model

    NASA Astrophysics Data System (ADS)

    Kukulka, Tobias; Jay, David A.

    2003-09-01

    This is the first part of a two-part investigation that applies nonstationary time series analysis methods and the St. Venant equations to the problem of understanding juvenile salmonid access to favorable shallow-water habitat in a tidal river. Habitat access is a function of river stage, tidal range, and the distribution of bed elevation. Part 1 models nonstationary tidal properties: species amplitudes and phases and tidal range. Part 2 models low-frequency river stage in the Lower Columbia River and reconstructs historical water levels, using the tidal model from part 1. To incorporate the nonstationary frictional effects of variable river discharge into the tidal model, we decompose the tidal wave into tidal species and calculate daily tidal range. Our one-dimensional tidal model is based on analytic wave solutions to the linearized St. Venant equation and uses six coefficients per tidal species to represent the upstream evolution of the frictionally damped tidal wave. The form of the coefficients is derived from the St. Venant equations, but their values are determined objectively from the data. About 50 station-years of surface elevation data collected (1981-2000) below Bonneville Dam (235 km from the ocean) were processed with a wavelet filter bank to retrieve time series of tidal species properties. A min-max filter was used to estimate daily tidal range. Tidal range, diurnal, and semidiurnal amplitudes were predicted with mean root mean square errors <30 mm, which is significantly more accurate than predictions obtained from harmonic analysis. Thus despite the compact form of our solution, we model nonstationary fluvial tidal properties with a high level of accuracy.

  14. Trace elements in the Mississippi River Delta outflow region: Behavior at high discharge

    SciTech Connect

    Shiller, A.M. ); Boyle, E.A. )

    1991-11-01

    Samples for dissolved trace element analysis were collected in surface waters of the plume of the Mississippi River during a period of high river discharge. These field data are compared with results of laboratory mixing experiments. The studies show that Cu, Ni, and Mo are largely unreactive in the plume. Surprisingly, Fe also appears to show little reactivity; the pronounced flocculation removal of Fe frequently observed in other estuaries is not seen in this system. This difference may be a consequence of the alkaline nature of the Mississippi which results in low dissolved Fe concentrations in the river (<50 nmol/kg). Zinc, another particle-reactive element, also shows little reactivity. This lack of reactivity for Zn, as well as Cu and Ni, is partly a result of the short residence time of plume waters in shallow areas affected by sedimentary interactions. The chromium distribution shows apparent non-conservative behavior indicative of estuarine removal; however, temporal variations in river concentrations is a more likely explanation for this behavior. For some of the elements, complex distributions occur as a consequence of the interplay of physical-chemical and/or biological processes with the dynamic mixing regime. For Cd, desorption from the suspended load plays a major role in determining the distribution. However, sedimentary input may also play a role in the spatial variability of Cd. For V, biological uptake in the plume exerts a strong influence on its distribution. At the time of this study, uptake was large enough to consume both the river flux of V as well as a substantial amount of vanadium supplied by the ocean.

  15. Coal geology and assessment of coal resources and reserves in the Powder River Basin, Wyoming and Montana

    USGS Publications Warehouse

    Luppens, James A.; Scott, David C.

    2015-01-01

    This report presents the final results of the first assessment of both coal resources and reserves for all significant coal beds in the entire Powder River Basin, northeastern Wyoming and southeastern Montana. The basin covers about 19,500 square miles, exclusive of the part of the basin within the Crow and Northern Cheyenne Indian Reservations in Montana. The Powder River Basin, which contains the largest resources of low-sulfur, low-ash, subbituminous coal in the United States, is the single most important coal basin in the United States. The U.S. Geological Survey used a geology-based assessment methodology to estimate an original coal resource of about 1.16 trillion short tons for 47 coal beds in the Powder River Basin; in-place (remaining) resources are about 1.15 trillion short tons. This is the first time that all beds were mapped individually over the entire basin. A total of 162 billion short tons of recoverable coal resources (coal reserve base) are estimated at a 10:1 stripping ratio or less. An estimated 25 billion short tons of that coal reserve base met the definition of reserves, which are resources that can be economically produced at or below the current sales price at the time of the evaluation. The total underground coal resource in coal beds 10–20 feet thick is estimated at 304 billion short tons.

  16. Impact of flood discharges of small rivers on delivery and fate of fluvial water and sediments at the northeastern coast of the Black Sea

    NASA Astrophysics Data System (ADS)

    Osadchiev, Alexander; Zavialov, Peter; Izhitskiy, Alexander

    2016-04-01

    This study is focused on influence of discharge of small rivers during flooding conditions on coastal water quality at the northeastern coast of the Black Sea. More than 50 rivers and watercourses are inflowing into the sea at the considered area between the city of Novorossiysk and the city of Sochi, while only 8 of them have annual discharge greater than 10 m3/s. All these rain-fed mountainous rivers with relatively small basins (below 900 km2) and steep slopes are characterized by very quick response of the discharge to precipitation events. For example, during a heavy rain on September 4-7, 2013 the discharge of the Sochi River increased from 3 m3/s to 230 m3/s, and these 4 days provided about 13% of average annual discharge of the Sochi River. The same processes are regularly registered for the majority of the considered rivers, except a few largest ones. Basing on satellite imagery and numerical modeling we evaluated influence of discharges of small rivers characterized by elevated delivery of terrigenous and anthropogenic pollutants during flooding conditions on coastal water quality. We showed that point-source spread of continental discharge dominated by large rivers under normal conditions switches to line-source spread from numerous small rivers situated along the coast which dramatically transforms transport pathways of suspended and dissolved constituents discharged with river waters.

  17. Satellite-Based Estimation of Water Discharge and Runoff in the Magdalena River, Northern Andes of Colombia

    NASA Astrophysics Data System (ADS)

    Restrepo, J. D.; Escobar Correa, R.; Kettner, A.; Brakenridge, G. R.

    2016-12-01

    The Magdalena River and its most important tributary, the Cauca, drain the northern Andes of Colombia. During the wet season, flood events affect the whole region and cause huge damage in low-income communities. Mitigation of such natural disasters in Colombia lacks science-supported tools for evaluating river response to extreme climate events. Here we introduce near-real-time estimations of river discharge towards technical capacity building for evaluation of flood magnitudes and variability along the Magdalena and Cauca. We use the River Watch version 3 system of the Dartmouth Flood Observatory (DFO) at five selected measurement sites on the two rivers. For each site, two different rating curves were constructed to transform microwave signal from TRMM, AMSR-E, AMRS-2, and GPM satellites into river discharge. The first rating curves were based on numerical discharge estimates from a global Water Balance Model (WBM); the second were obtained from the relationship between satellite signal and measured river discharge at ground gauging stations at nearby locations. Determination coefficients (R2) between observed versus satellite-derived daily discharge data, range from 0.38 to 0.57 in the upper basin, whereas in the middle of the basin R2 values vary between 0.47 and 0.64. In the lower basin, observed R2 values are lower and range from 0.32 to 0.4. Once time lags between the microwave satellite signal and river discharge from either WBM estimates or ground-based gauging stations are taken into account, the R2 values increase considerably. The time series of satellite-based river discharge during the 1998 - 2016 period show high inter-annual variability as well as strong pulses associated with the ENSO (La Niña/El Niño) cycle. Numerical runoff magnitude estimates at peaks of extreme climatic anomalies are more correlated than stream flows measured at ground-based gauging stations. In fluvial systems such as the Magdalena, characterized by high spatial variability

  18. Power law time dependence of river flood decay and its relationship to long term discharge frequency distribution. [California

    NASA Technical Reports Server (NTRS)

    Schubert, G.; Lingenfelter, R. E.

    1973-01-01

    Investigations have continued into the possibility that significant information on stream flow rates can be obtained from aerial and satellite imagery of river meander patterns by seeking a correlation between the meander and discharge spectra of rivers. Such a correlation could provide the basis for a simple and inexpensive technique for remote sensing of the water resources of large geographical areas, eliminating the need for much hydrologic recording. The investigation of the nature of the meander and discharge spectra and their interrelationship can also contribute to a more fundamental understanding of the processes of both river meander formation and drainage of large basins. It has been found that floods decay with an inverse power law dependence on time. The exponent of this dependence varies from river to river and even from station to station along the same river. This power law time dependence makes possible the forecasting of river discharge with an uncertainty of about 5% for as long as a month following the flood peak.

  19. Locating Ground-Water Discharge in the Hanford Reach of the Columbia River

    SciTech Connect

    Lee, D.R.; Geist, D.R.; Saldi, K.; Hartwig, D.; Cooper, T.

    1997-03-01

    A bottom-contacting probe for measuring electrical conductivity at the sediment-water interface was used to scan the bed of the Columbia River adjacent to the Hanford Site in southeast Washington State during a 10-day investigation. Four river-sections, each about a kilometer in length, were scanned for variations in electrical conductivity. The probe was towed along the riverbed at a speed of 1 m/s and is position was recorded using a Global Positioning System. The bottom tows revealed several areas of elevated electrical conductivity. Where these anomalies were relatively easy to access, piezometers were driven into the riverbed and porewater electrical conductivity ranged from 111 to 150 uS/cm. The piezometers, placed in electrical conductivity “hotspots,” yielded chemical or isotopic data consistent with previous analyses of water taken from monitoring wells and visible shoreline seeps. Tritium, nitrate, and chromium exceeded water quality standards in some porewaters. The highest tritium and nitrate levels were found near the Old Hanford Townsite at 120,000 pCi/L (+ 5,880 pCi/L total propagated analytical uncertainty) and ug/L (+ 5,880 ug/L), respectively. The maximum chromium (total and hexavalent) levels were found near 100-H reactor area where unfiltered porewater total chromium was 1,900 ug/L (+ 798 ug/L) and hexavalent chromium was 20 ug/L. The electrical conductivity probe provided rapid, cost-effective reconnaissance for ground-water discharge areas when used in combination with conventional piezometers. It may be possible to obtain quantitative estimates of both natural and contaminated ground-water discharge in the Hanford Reach with more extensive surveys of river bottom.

  20. Influence of Amur River discharge on phytoplankton photophysiology in the Sea of Okhotsk during late summer

    NASA Astrophysics Data System (ADS)

    Isada, Tomonori; Iida, Takahiro; Liu, Hongbin; Saitoh, Sei-Ichi; Nishioka, Jun; Nakatsuka, Takeshi; Suzuki, Koji

    2013-04-01

    We investigated the photosynthetic parameters of phytoplankton in the Sea of Okhotsk during the late summer of 2006 to characterize their spatiotemporal variability and to test the hypothesis that discharge from the Amur River could influence the algal photophysiology. The highest maximum quantum yield of carbon fixation in photosynthesis (Φcmax; 0.098 mol C mol photons-1) was found near the Amur River mouth, where nitrate was depleted. However, none of the photosynthetic parameters, including primary productivity (PP) at the surface, were correlated with temperature, daily photosynthetically available radiation (PAR), or ambient nutrient concentrations. Variations in Φcmax depended on the variations in not only the mean chlorophyll a specific absorption coefficient of phytoplankton (ā*ph) but also the slope index of the absorption coefficient of phytoplankton (aph slope), an indicator for the ratio of nonphotosynthetic carotenoids to photosynthetic carotenoids. These results indicated that the phytoplankton assemblages acclimated to the ambient light conditions by regulating their cellular pigments. Additionally, ā*ph and euphotic depth (Zeu) were significantly correlated with salinity, suggesting that photoacclimation of the phytoplankton assemblages observed in this study could be induced by discharge of Amur River. Because spatiotemporal variations in PP were concomitant with Φcmax, ā*ph, and the chlorophyll a concentration, PP models based on inherent optical property (IOP) were suitable for estimating PP in the Sea of Okhotsk. This study is the first to investigate the factors controlling phytoplankton photophysiology in the Sea of Okhotsk, one of the highest primary production areas in the world.

  1. Discharge prediction in the Upper Senegal River using remote sensing data

    NASA Astrophysics Data System (ADS)

    Ceccarini, Iacopo; Raso, Luciano; Steele-Dunne, Susan; Hrachowitz, Markus; Nijzink, Remko; Bodian, Ansoumana; Claps, Pierluigi

    2017-04-01

    The Upper Senegal River, West Africa, is a poorly gauged basin. Nevertheless, discharge predictions are required in this river for the optimal operation of the downstream Manantali reservoir, flood forecasting, development plans for the entire basin and studies for adaptation to climate change. Despite the need for reliable discharge predictions, currently available rainfall-runoff models for this basin provide only poor performances, particularly during extreme regimes, both low-flow and high-flow. In this research we develop a rainfall-runoff model that combines remote-sensing input data and a-priori knowledge on catchment physical characteristics. This semi-distributed model, is based on conceptual numerical descriptions of hydrological processes at the catchment scale. Because of the lack of reliable input data from ground observations, we use the Tropical Rainfall Measuring Mission (TRMM) remote-sensing data for precipitation and the Global Land Evaporation Amsterdam Model (GLEAM) for the terrestrial potential evaporation. The model parameters are selected by a combination of calibration, by match of observed output and considering a large set of hydrological signatures, as well as a-priori knowledge on the catchment. The Generalized Likelihood Uncertainty Estimation (GLUE) method was used to choose the most likely range in which the parameter sets belong. Analysis of different experiments enhances our understanding on the added value of distributed remote-sensing data and a-priori information in rainfall-runoff modelling. Results of this research will be used for decision making at different scales, contributing to a rational use of water resources in this river.

  2. Stable isotope record of late holocene salinity and river discharge in san francisco bay, california

    SciTech Connect

    Ingram, B.L.; Ingle, J.C.; Conrad, M.E

    1995-01-31

    Oxygen and carbon isotopic measurements of fossil mollusks from San Francisco Bay are used to derive a record of paleosalinity and paleostreamflow for the past 5,900 years. The delta(18)O and delta(13)C values of river water (-12 parts per thousand and -9 parts per thousand) are markedly different than seawater (0 parts per thousand and 1 parts per thousand), and vary systematically as a function of salinity in the estuary. The data show that annually averaged salinity in the south-central part of the Bay was ve