Measuring flood discharge in unstable stream channels using ground-penetrating radar
K.R. Spicer, J. E. Costa, G. Placzek
1997, Geology (25) 423-426
Field experiments were conducted to test the ability of ground-penetrating radar (GPR) to measure stream-channel cross sections at high flows without the necessity of placing instruments in the water. Experiments were conducted at four U.S. Geological Survey gaging stations in southwest Washington State....
Case study modeling of turbulent and mesoscale fluxes over the BOREAS region
P.L. Vidale, R.A. Pielke Sr., L. T. Steyaert, A. Barr
1997, Journal of Geophysical Research D: Atmospheres (102) 29167-29188
Results from aircraft and surface observations provided evidence for the existence of mesoscale circulations over the Boreal Ecosystem-Atmosphere Study (BOREAS) domain. Using an integrated approach that included the use of analytical modeling, numerical modeling, and data analysis, we have found that there are substantial contributions to the total budgets of...
A new approach for analyzing bird densities from variable circular-plot counts
S.G. Fancy
1997, Pacific Science (51) 107-114
An approach for calculating bird densities from variable circular-plot counts is described. The approach differs from previous methods in that data from several surveys are pooled and detection distances are adjusted as if all distances were recorded by a single observer under a given set of field conditions. Adjustments for...
Long-term growth trends of baldcypress (Taxodium distichum (L.) rich.) at Caddo Lake, Texas
B. D. Keeland, P.J. Young
1997, Wetlands (17) 559-566
Caddo Lake, situated on the border of northeast Texas and northwest Louisiana, USA is a medium-sized lake dominated by stands of baldcypress (Taxodiwn distichum). A study of tree growth was initiated at Caddo Lake to address concerns about the health of the baldcypress ecosystem. The lake has been subjected to...
Climate change and the detection of trends in annual runoff
G. J. McCabe Jr., D.M. Wolock
1997, Climate Research (8) 129-134
This study examines the statistical likelihood of detecting a trend in annual runoff given an assumed change in mean annual runoff, the underlying year-to-year variability in runoff, and serial correlation of annual runoff. Means, standard deviations, and lag-1 serial correlations of annual runoff were computed for 585 stream gages in...
Estimating millet production for famine early warning: An application of crop simulation modelling using satellite and ground-based data in Burkina Faso
P. K. Thornton, W. T. Bowen, A. C. Ravelo, P. W. Wilkens, G. Farmer, J. Brock, J. E. Brink
1997, Agricultural and Forest Meteorology (83) 95-112
Early warning of impending poor crop harvests in highly variable environments can allow policy makers the time they need to take appropriate action to ameliorate the effects of regional food shortages on vulnerable rural and urban populations. Crop production estimates for the current season can be obtained using crop simulation...
Long time-series of turbid coastal water using AVHRR: An example from Florida Bay, USA
R. P. Stumpf, M.L. Frayer
1997, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
The AVHRR can provide information on the reflectance of turbid case II water, permitting examination of large estuaries and plumes from major rivers. The AVHRR has been onboard several NOAA satellites, with afternoon overpasses since 1981, offering a long time-series to examine changes in coastal water. We are using AVHRR...
Spatial analysis of temperature (BHT/DST) data and consequences for heat-flow determination in sedimentary basins
A. Forster, D. F. Merriam, J.C. Davis
1997, Conference Paper, International Journal of Earth Sciences
Large numbers of bottom-hole temperatures (BHTs) and temperatures measured during drill-stem tests (DSTs) are available in areas explored for hydrocarbons, but their usefulness for estimating geothermal gradients and heat-flow density is limited. We investigated a large data set of BHT and DST measurements taken in boreholes in the American Midcontinent,...
Effects of road management on movement and survival of Roosevelt elk
Eric K. Cole, Michael D. Pope, Robert G. Anthony
1997, Journal of Wildlife Management (61) 1115-1126
Road closures frequently are used to manage for Rocky Mountain elk (Cervus elaphus nelsoni), but no studies have evaluated the effects of limited vehicle access on movements and survival of Roosevelt elk (C. elaphus roosevelti). We studied movements and survival of female Roosevelt elk before Road Management Areas (RMA) were...
Landsat-7 Enhanced Thematic Mapper plus radiometric calibration
B. L. Markham, Wayne C. Boncyk, D. L. Helder, J. L. Barker
1997, Canadian Journal of Remote Sensing (23) 318-332
Landsat-7 is currently being built and tested for launch in 1998. The Enhanced Thematic Mapper Plus (ETM+) sensor for Landsat-7, a derivative of the highly successful Thematic Mapper (TM) sensors on Landsats 4 and 5, and the Landsat-7 ground system are being built to provide enhanced radiometric calibration performance. In...
Kinetics of the coesite to quartz transformation
J.L. Mosenfelder, S.R. Bohlen
1997, Earth and Planetary Science Letters (153) 133-147
The survival of coesite in ultrahigh-pressure (UHP) rocks has important implications for the exhumation of subducted crustal rocks. We have conducted experiments to study the mechanism and rate of the coesite→quartz transformation using polycrystalline coesite aggregates, fabricated by devitrifying silica glass cylinders...
Soluble trace elements and total mercury in Arctic Alaskan snow
E. Snyder-Conn, John R. Garbarino, Gerald L. Hoffman, A. Oelkers
1997, Arctic (50) 201-215
Ultraclean field and laboratory procedures were used to examine trace element concentrations in northern Alaskan snow. Sixteen soluble trace elements and total mercury were determined in snow core samples representing the annual snowfall deposited during the 1993-94 season at two sites in the Prudhoe Bay oil field and nine sites...
Some thoughts on problems associated with various sampling media used for environmental monitoring
A. J. Horowitz
1997, Conference Paper, Analyst
Modern analytical instrumentation is capable of measuring a variety of trace elements at concentrations down into the single or double digit parts-per-trillion (ng l-1) range. This holds for the three most common sample media currently used in environmental monitoring programs: filtered water, whole-water and separated suspended sediment. Unfortunately, current analytical...
A study of the temporal variability of atrazine in private well water. Part I: Study design, implementation, and database development
M. Lorber, Kevin Johnson, B. Kross, P. Pinsky, L. Burmeister, M. Thurman, A. Wilkins, G. Hallberg
1997, Environmental Monitoring and Assessment (47) 175-195
In 1988, the Iowa Department of Natural Resources, along with the University of Iowa conducted the Statewide Rural Well Water Survey, commonly known as SWRL. A total of 686 private rural drinking water wells was selected by use of a probability sample and tested for pesticides and nitrates. Sixty-eight of...
Distribution and stability of eelgrass beds at Izembek Lagoon, Alaska
David H. Ward, Carl J. Markon, David C. Douglas
1997, Aquatic Botany (58) 229-240
Spatial change in eelgrass meadows, Zostera marina L., was assessed between 1978 and 1987 and between 1987 and 1995 at Izembek Lagoon, Alaska. Change in total extent was evaluated through a map to map comparison of data interpreted from a 1978 Landsat multi-spectral scanner image and 1987 black and white...
Potential effects of climate change on aquatic ecosystems of the Great Plains of North America
A.P. Covich, S.C. Fritz, P.J. Lamb, R.D. Marzolf, W.J. Matthews, K.A. Poiani, E.E. Prepas, M.B. Richman, T. C. Winter
1997, Hydrological Processes (11) 993-1021
The Great Plains landscape is less topographically complex than most other regions within North America, but diverse aquatic ecosystems, such as playas, pothole lakes, ox-bow lakes, springs, groundwater aquifers, intermittent and ephemeral streams, as well as large rivers and wetlands, are highly dynamic and responsive to extreme climatic fluctuations. We...
Morphology and distribution of seamounts surrounding Easter Island
Y. Rappaport, D. F. Naar, C.C. Barton, Z.-J. Liu, R.N. Hey
1997, Journal of Geophysical Research B: Solid Earth (102) 24713-24728
We investigate the morphology and distribution of a seamount population on a section of seafloor influenced by both superfast seafloor spreading and hotspot volcanism. The population under investigation is part of a broad chain of seamounts extending eastward from the East Pacific Rise, near Easter Island. In order to define...
Beryllium geochemistry in soils: Evaluation of 10Be/9Be ratios in authigenic minerals as a basis for age models
E. Barg, D. Lal, M.J. Pavich, M.W. Caffee, J. R. Southon
1997, Chemical Geology (140) 237-258
Soils contain a diverse and complex set of chemicals and minerals. Being an 'open system', both in the chemical and nuclear sense, soils have defied quantitative nuclear dating. However, based on the published studies of the cosmogenic atmospheric 10Be in soils, its relatively long half-life (1.5 Ma), and the fact...
XRD measurement of mean crystallite thickness of illite and illite/smectite: Reappraisal of the Kubler index and the Scherrer equation
Victor A. Drits, Jan Srodon, D. D. Eberl
1997, Clays and Clay Minerals (45) 461-475
The standard form of the Scherrer equation, which has been used to calculate the mean thickness of the coherent scattering domain (CSD) of illite crystals from X-ray diffraction (XRD) full width data at half maximum (FWHM) intensity, employs a constant, Ksh, of 0.89. Use of this constant is unjustified, even...
Initial results of high-resolution sea-floor mapping offshore of the New York - New Jersey metropolitan area using sidescan sonar
W. C. Schwab, M. A. Allison, W. Corso, L. L. Lotto, B. Butman, Marilyn R. Buchholtz ten Brink, J. F. Denny, W. W. Danforth, D.S. Foster
1997, Northeastern Geology and Environmental Sciences (19) 243-262
High-resolution seismic, sidescan-sonar, multibeam bathymetry, and sediment sampling techniques were used to map the surficial geology and shallow subbottom stratigraphy of a segment of the inner shelf and nearshore region of New York-New Jersey metropolitan area. Preliminary analyses of these data provide a sedimentologic framework for addressing a wide range...
DDE poisoning in an adult bald eagle
D.K. Garcelon, N. J. Thomas
1997, Journal of Wildlife Diseases (33) 299-303
A 12-year-old female bald eagle (Haliaeetus leucocephalus) was found in May 1993 on Santa Catalina Island, California (USA), in a debilitated condition, exhibiting ataxia and tremors; it died within hours. On necropsy, the bird was emaciated but had no evidence of disease or...
Evaluation of field and laboratory research on scour at bridge piers in the United States
David S. Mueller, J. Sterling Jones
1997, Conference Paper, Proceedings, Congress of the International Association of Hydraulic Research, IAHR
The Federal Highway Administration sponsored a laboratory research at Colorado State University and field data collection with the US Geological Survey, to evaluate the effects of bed material on the depth of scour. Correction factors are compared to include the effect of bed material in the HEC-18 equation. The HEC-18...
Debris-flow hazard map units from gridded probabilities
Russell H. Campbell, Richard L. Bernknopf
1997, Conference Paper, International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment, Proceedings
The common statistical practice of dividing a range of probabilities into equal probability intervals may not result in useful landslide-hazard map units for areas populated by equal-area cells, each of which has a unique probability. Most hazard map areas contain very large numbers of cells having low probability of failure,...
Scale and modeling issues in water resources planning
H.F. Lins, D.M. Wolock, G.J. McCabe
1997, Climatic Change (37) 63-88
Resource planners and managers interested in utilizing climate model output as part of their operational activities immediately confront the dilemma of scale discordance. Their functional responsibilities cover relatively small geographical areas and necessarily require data of relatively high spatial resolution. Climate models cover a large geographical, i.e. global, domain and...
A self-modifying cellular automaton model of historical urbanization in the San Francisco Bay area
K.C. Clarke, S. Hoppen, L. Gaydos
1997, Environment and Planning B: Planning and Design (24) 247-261
In this paper we describe a cellular automaton (CA) simulation model developed to predict urban growth as part of a project for estimating the regional and broader impact of urbanization on the San Francisco Bay area's climate. The rules of the model are more complex than those of a typical...
