Predicting recolonization patterns and interactions between potamodromous and anadromous salmonids in response to dam removal in the Elwha River, Washington State, USA
S.J. Brenkman, G.R. Pess, C.E. Torgersen, K.K. Kloehn, J.J. Duda, S.C. Corbett
2008, Northwest Science (82) 91-106
The restoration of salmonids in the Elwha River following dam removal will cause interactions between anadromous and potamodromous forms as recolonization occurs in upstream and downstream directions. Anadromous salmonids are expected to recolonize historic habitats, and rainbow trout (Oncorhynchus mykiss) and bull trout (Salvelinus confluentus) isolated above the dams for...
Key elements of regional seismic velocity models for long period ground motion simulations
T.M. Brocher
2008, Journal of Seismology (12) 217-221
Regional 3-D seismic velocity models used for broadband strong motion simulations must include compressional-wave velocity (Vp), shear-wave velocity (Vs), intrinsic attenuation (Qp, Qs), and density. Vs and Qs are the most important of these parameters because the strongest ground motions are generated chiefly by shear- and surface-wave arrivals. Because Vp...
Measuring gravity currents in the Chicago River, Chicago, Illinois
K. A. Oberg, J. A. Czuba, K. K. Johnson
2008, Conference Paper, Proceedings of the IEEE working conference on current measurement technology
Recent studies of the Chicago River have determined that gravity currents are responsible for persistent bidirectional flows that have been observed in the river. A gravity current is the flow of one fluid within another caused by a density difference between the fluids. These studies demonstrated how acoustic Doppler current...
Fate and transport of pesticides in the ground water systems of southwest Georgia, 1993-2005
M.S. Dalton, E. A. Frick
2008, Conference Paper, Journal of Environmental Quality
Modern agricultural practices in the United States have resulted in nearly unrivaled efficiency and productivity. Unfortunately, there is also the potential for release of these compounds to the environment and consequent adverse affects on wildlife and human populations. Since 1993, the National Water-Quality Assessment (NAWQA) program of the U.S. Geological...
Dual-RiverSonde measurements of two-dimensional river flow patterns
C.C. Teague, D.E. Barrick, P.M. Lilleboe, Ralph T. Cheng, Paul Stumpner, Jon R. Burau
2008, Conference Paper, Proceedings of the IEEE Working Conference on Current Measurement Technology
Two-dimensional river flow patterns have been measured using a pair of RiverSondes in two experiments in the Sacramento-San Joaquin River Delta system of central California during April and October 2007. An experiment was conducted at Walnut Grove, California in order to explore the use of dual RiverSondes to measure flow...
Agriculture-related trends in groundwater quality of the glacial deposits aquifer, central Wisconsin
D. A. Saad
2008, Conference Paper, Journal of Environmental Quality
Measuring and understanding trends in groundwater quality is necessary for determining whether changes in land-management practices have an effect on groundwater quality. This paper describes an approach that was used to measure and understand trends using data from two groundwater studies conducted in central Wisconsin as part of the USGS...
Deformation and stress-change modeling at Sierra Negra volcano, Galapagos, from ENVISAT INSAR and GPS observations
Sigurjon Jonsson, W.W. Chadwick, Michael Poland, D. Geist
2008, Conference Paper, European Space Agency, (Special Publication) ESA SP
We use radar interferograms and GPS observations to constrain models of magma accumulation and faulting at Sierra Negra volcano, Galápagos, during the years before its 2005 eruption. The data have shown ~5 m of pre-eruption uplift and multiple trapdoor faulting events on an intra-caldera fault system. We find the...
The release of dissolved actinium to the ocean: A global comparison of different end-members
W. Geibert, M. Charette, G. Kim, W.S. Moore, J. Street, M. Young, A. Paytan
2008, Marine Chemistry (109) 409-420
The measurement of short-lived 223Ra often involves a second measurement for supported activities, which represents 227Ac in the sample. Here we exploit this fact, presenting a set of 284 values on the oceanic distribution of 227Ac, which was collected when analyzing water samples for short-lived radium isotopes by the radium...
Fluctuating Arctic Sea ice thickness changes estimated by an in situ learned and empirically forced neural network model
G. I. Belchansky, David C. Douglas, Nikita G. Platonov
2008, Journal of Climate (21) 716-729
Sea ice thickness (SIT) is a key parameter of scientific interest because understanding the natural spatiotemporal variability of ice thickness is critical for improving global climate models. In this paper, changes in Arctic SIT during 1982-2003 are examined using a neural network (NN) algorithm trained with in situ submarine ice...
Using the FORE-SCE model to project land-cover change in the southeastern United States
Terry Sohl, Kristi L. Sayler
2008, Ecological Modelling (219) 49-65
A wide variety of ecological applications require spatially explicit current and projected land-use and land-cover data. The southeastern United States has experienced massive land-use change since European settlement and continues to experience extremely high rates of forest cutting, significant urban development, and changes in agricultural land use. Forest-cover patterns and...
A trade-off between model resolution and variance with selected Rayleigh-wave data
J. Xia, R. D. Miller, Y. Xu
2008, Conference Paper, SEG Technical Program Expanded Abstracts
Inversion of multimode surface-wave data is of increasing interest in the near-surface geophysics community. For a given near-surface geophysical problem, it is essential to understand how well the data, calculated according to a layered-earth model, might match the observed data. A data-resolution matrix is a function of the data kernel...
Determination of methane concentrations in water in equilibrium with sI methane hydrate in the absence of a vapor phase by in situ Raman spectroscopy
W. Lu, I.-M. Chou, R.C. Burruss
2008, Geochimica et Cosmochimica Acta (72) 412-422
Most submarine gas hydrates are located within the two-phase equilibrium region of hydrate and interstitial water with pressures (P) ranging from 8 to 60 MPa and temperatures (T) from 275 to 293 K. However, current measurements of solubilities of methane in equilibrium with hydrate in the absence of a vapor...
Integrated analysis of well logs and seismic data to estimate gas hydrate concentrations at Keathley Canyon, Gulf of Mexico
Myung W. Lee, T. S. Collett
2008, Marine and Petroleum Geology (25) 924-931
Accurately detecting and quantifying gas hydrate or free gas in sediments from seismic data require downhole well-log data to calibrate the physical properties of the gas hydrate-/free gas-bearing sediments. As part of the Gulf of Mexico Joint Industry Program, a series of wells were either cored or drilled in the...
Estimation of the bottleneck size in Florida panthers
M. Culver, P.W. Hedrick, K. Murphy, S. O'Brien, M.G. Hornocker
2008, Animal Conservation (11) 104-110
We have estimated the extent of genetic variation in museum (1890s) and contemporary (1980s) samples of Florida panthers Puma concolor coryi for both nuclear loci and mtDNA. The microsatellite heterozygosity in the contemporary sample was only 0.325 that in the museum samples although our sample size and number of loci...
4D volcano gravimetry
Maurizio Battaglia, J. Gottsmann, D. Carbone, J. Fernandez
2008, Geophysics (73) WA3-WA18
Time-dependent gravimetric measurements can detect subsurface processes long before magma flow leads to earthquakes or other eruption precursors. The ability of gravity measurements to detect subsurface mass flow is greatly enhanced if gravity measurements are analyzed and modeled with ground-deformation data. Obtaining the maximum information from microgravity studies requires careful...
The Landsat Image Mosaic of Antarctica
Robert Bindschadler, P. Vornberger, A. Fleming, A. Fox, J. Mullins, D. Binnie, S.J. Paulsen, Brian J. Granneman, D. Gorodetzky
2008, Remote Sensing of Environment (112) 4214-4226
The Landsat Image Mosaic of Antarctica (LIMA) is the first true-color, high-spatial-resolution image of the seventh continent. It is constructed from nearly 1100 individually selected Landsat-7 ETM+ scenes. Each image was orthorectified and adjusted for geometric, sensor and illumination variations to a standardized, almost seamless surface reflectance product. Mosaicing to...
Depth distribution dynamics of the sculpin community in Lake Michigan
C.P. Madenjian, D.B. Bunnell
2008, Transactions of the American Fisheries Society (137) 1346-1357
Using data from our annual lakewide bottom trawl survey of Lake Michigan, we calculated the mean depths of capture for deepwater sculpin Myoxocephalus thompsonii and slimy sculpin Cottus cognatus for each combination of transect (Frankfort, Ludington, Saugatuck, and Manistique in Michigan, Waukegan in Illinois, and Port Washington and Sturgeon Bay...
Building hierarchical models of avian distributions for the State of Georgia
J.E. Howell, J.T. Peterson, M.J. Conroy
2008, Journal of Wildlife Management (72) 168-178
To predict the distributions of breeding birds in the state of Georgia, USA, we built hierarchical models consisting of 4 levels of nested mapping units of decreasing area: 90,000 ha, 3,600 ha, 144 ha, and 5.76 ha. We used the Partners in Flight database of point counts to generate presence...
Limited change in dune mobility in response to a large decrease in wind power in semi-arid northern China since the 1970s
J.A. Mason, J. B. Swinehart, H. Lu, X. Miao, P. Cha, Y. Zhou
2008, Geomorphology (102) 351-363
The climatic controls on dune mobility, especially the relative importance of wind strength, remain incompletely understood. This is a key research problem in semi-arid northern China, both for interpreting past dune activity as evidence of paleoclimate and for predicting future environmental change. Potential eolian sand transport, which is approximately proportional...
Identification of spectral units on Phoebe
A. Coradini, F. Tosi, A.I. Gavrishin, F. Capaccioni, P. Cerroni, G. Filacchione, A. Adriani, R. H. Brown, G. Bellucci, V. Formisano, E. D’Aversa, J. I. Lunine, K. H. Baines, J.-P. Bibring, B. J. Buratti, R. N. Clark, D. P. Cruikshank, M. Combes, P. Drossart, R. Jaumann, Y. Langevin, D. L. Matson, T. B. McCord, V. Mennella, R.M. Nelson, P. D. Nicholson, B. Sicardy, Christophe Sotin, M.M. Hedman, G. B. Hansen, C. A. Hibbitts, M. Showalter, C. Griffith, G. Strazzulla
2008, Icarus (193) 233-251
We apply a multivariate statistical method to the Phoebe spectra collected by the VIMS experiment onboard the Cassini spacecraft during the flyby of June 2004. The G-mode clustering method, which permits identification of the most important features in a spectrum, is used on a small subset of data, characterized by...
Northerly surface winds over the eastern North Pacific Ocean in spring and summer
S.V. Taylor, D.R. Cayan, N.E. Graham, K.P. Georgakakos
2008, Journal of Geophysical Research D: Atmospheres (113)
Persistent spring and summer northerly surface winds are the defining climatological feature of the western coast of North America, especially south of the Oregon coast. Northerly surface winds are important for upwelling and a vast array of other biological, oceanic, and atmospheric processes. Intermittence in northerly coastal surface wind is...
Assessing habitat use by breeding Great Blue Herons (Ardea herodias) on the Upper Mississippi River, USA
E.M. Kirsch, B. Ickes, D.A. Olsen
2008, Waterbirds (31) 252-267
Approximately 7,610 to 3,175 pairs of Great Blue Herons (Ardea herodias) nested along 420 river km of the Upper Mississippi River (UMR) from 1993 to 2003. Numbers declined precipitously in the mid-1990s stabilizing somewhat in the early 2000s. The average number of nests in colonies was 349 (SD =...
Patterns of volcanotectonic seismicity and stress during the ongoing eruption of the Soufrière Hills Volcano, Montserrat (1995-2007)
D.C. Roman, S. De Angelis, J.L. Latchman, Rickie White
2008, Journal of Volcanology and Geothermal Research (173) 230-244
The ongoing eruption of the Soufrière Hills Volcano, Montserrat, has been accompanied throughout by varying levels of high-frequency, ‘volcanotectonic’ (VT), seismicity. These earthquakes reflect the brittle response of the host rock to stresses generated within the magmatic system and thus reveal interesting and useful information about the structure of the...
Integrating remotely sensed land cover observations and a biogeochemical model for estimating forest ecosystem carbon dynamics
J. Liu, S. Liu, Thomas R. Loveland, L.L. Tieszen
2008, Ecological Modelling (219) 361-372
Land cover change is one of the key driving forces for ecosystem carbon (C) dynamics. We present an approach for using sequential remotely sensed land cover observations and a biogeochemical model to estimate contemporary and future ecosystem carbon trends. We applied the General Ensemble Biogeochemical Modelling System (GEMS) for the...
Application of RHIZON samplers to obtain high-resolution pore-fluid records during geochemical investigations of gas hydrate systems
John W. Pohlman, M Riedel, William F. Waite, K. Rose, L. Lapham
2008, Fire in the Ice: NETL Methane Hydrate Newsletter (8) 16-17
Obtaining accurate, high-resolution profiles of pore fluid constituents is critical for characterizing the subsurface geochemistry of hydrate-bearing sediments. Tightly-constrained downcore profiles provide clues about fluid sources, fluid flow, and the milieu of chemical and diagenetic reactions, all of which are used to interpret where and why gas and gas hydrate...
