A modular approach to addressing model design, scale, and parameter estimation issues in distributed hydrological modelling
G.H. Leavesley, S.L. Markstrom, Pedro J. Restrepo, Roland J. Viger
2002, Hydrological Processes (16) 173-187
A modular approach to model design and construction provides a flexible framework in which to focus the multidisciplinary research and operational efforts needed to facilitate the development, selection, and application of the most robust distributed modelling methods. A variety of modular approaches have been developed, but with little consideration for...
Adaptive moving mesh methods for simulating one-dimensional groundwater problems with sharp moving fronts
W. Huang, Lingyun Zheng, X. Zhan
2002, International Journal for Numerical Methods in Engineering (54) 1579-1603
Accurate modelling of groundwater flow and transport with sharp moving fronts often involves high computational cost, when a fixed/uniform mesh is used. In this paper, we investigate the modelling of groundwater problems using a particular adaptive mesh method called the moving mesh partial differential equation approach. With this approach, the...
Coniform stromatolites from geothermal systems, North Island, New Zealand
Brian Jones, Robin W. Renaut, Michael R. Rosen, Kevin M. Ansdell
2002, Palaios (17) 84-103
Coniform stromatolites are found in several sites in the Tokaanu and Whakarewarewa geothermal areas of North Island, New Zealand. At Tokaanu, silicification of these stromatolites is taking place in Kirihoro, a shallow hot springfed pool. At Whakarewarewa, subfossil silicified coniform stromatolites are found on the floor of "Waikite Pool" on...
Comparison of stomach contents of haddock (Melanogrammus aeglefinus) from the 1981 and 1991 North Sea International Stomach Sampling Projects
S.A. Adlerstein, A. Temming, N. Mergardt
2002, ICES Journal of Marine Science (59) 497-515
This study analyses data from over 20 000 haddock stomachs collected during the 1981 and 1991 Stomach Sampling Projects of the North Sea. Sampling was within the framework of the Multispecies Virtual Population Analysis (MSVPA) for fisheries stock assessment. In 1981 stomachs were collected to calculate input feeding parameters from...
Supporting user-defined granularities in a spatiotemporal conceptual model
V. Khatri, S. Ram, R.T. Snodgrass, G. M. O’Brien
2002, Conference Paper, Annals of Mathematics and Artificial Intelligence
Granularities are integral to spatial and temporal data. A large number of applications require storage of facts along with their temporal and spatial context, which needs to be expressed in terms of appropriate granularities. For many real-world applications, a single granularity in the database is insufficient. In order to support...
Comparison of an algebraic multigrid algorithm to two iterative solvers used for modeling ground water flow and transport
R.L. Detwiler, S. Mehl, H. Rajaram, W.W. Cheung
2002, Ground Water (40) 267-272
Numerical solution of large-scale ground water flow and transport problems is often constrained by the convergence behavior of the iterative solvers used to solve the resulting systems of equations. We demonstrate the ability of an algebraic multigrid algorithm (AMG) to efficiently solve the large, sparse systems of equations that result...
Maturation and fecundity of a stock-enhanced population of striped bass in the Savannah River Estuary, U.S.A.
T.A. Will, T.R. Reinert, Cecil A. Jennings
2002, Journal of Fish Biology (60) 532-544
The striped bass Morone saxatilis population in the Savannah River (south-eastern U.S.A.) collapsed in the 1980s, and recent efforts to restore the population have resulted in increased catch-per-unit-effort (CPUE) of striped bass in the Savannah River Estuary (SRE). The abundance of eggs and larvae, however, remain well below historic levels....
Simulations of seismic hazard for the Pacific Northwest of the United States from earthquakes associated with the Cascadia subduction zone
M.D. Petersen, C.H. Cramer, A.D. Frankel
2002, Pure and Applied Geophysics (159) 2147-2168
We investigate the impact of different rupture and attenuation models for the Cascadia subduction zone by simulating seismic hazard models for the Pacific Northwest of the U.S. at 2% probability of exceedance in 50 years. We calculate the sensitivity of hazard (probabilistic ground motions) to the source parameters and the...
Molecular analysis of a 11 700-year-old rodent midden from the Atacama Desert, Chile
M. Kuch, N. Rohland, J.L. Betancourt, C. Latorre, S. Steppan, H.N. Poinar
2002, Molecular Ecology (11) 913-924
DNA was extracted from an 11 700-year-old rodent midden from the Atacama Desert, Chile and the chloroplast and animal mitochondrial DNA (mtDNA) gene sequences were analysed to investigate the floral environment surrounding the midden, and the identity of the midden agent. The plant sequences, together with the macroscopic identifications, suggest...
Aftershock triggering by complete Coulomb stress changes
Debi Kilb, J. Gomberg, P. Bodin
2002, Journal of Geophysical Research B: Solid Earth (107) ESE 2-1-ESE 2-14
We examine the correlation between seismicity rate change following the 1992, M7.3, Landers, California, earthquake and characteristics of the complete Coulomb failure stress (CFS) changes (ΔCFS(t)) that this earthquake generated. At close distances the time-varying “dynamic” portion of the stress change depends on how the rupture develops temporally and spatially and...
Invertebrate biomass: associations with lesser prairie-chicken habitat use and sand sagebrush density in southwestern Kansas
B. Jamison, R.J. Robel, J.S. Pontius, R.D. Applegate
2002, Wildlife Society Bulletin (30) 517-526
Invertebrates are important food sources for lesser prairie-chicken (Tympanuchus pallidicinctus) adults and broods. We compared invertebrate biomass in areas used and not used by lesser prairie-chicken adults and broods. We used radiotelemetry to determine use and non-use areas in sand sagebrush (Artemisia filifolia) prairie in southwestern Kansas and sampled invertebrate...
Status and trends in atmospheric deposition and emissions near Atlanta, Georgia, 1986-99
N.E. Peters, T.P. Meyers, Brent T. Aulenbach
2002, Atmospheric Environment (36) 1577-1588
Wet and dry atmospheric deposition were investigated from weekly data, 1986-99 (1986-97 for dry deposition) at the Panola Mountain Research Watershed (PMRW), a forested research site 25 km, southeast of Atlanta, Georgia. Furthermore, the wet deposition was compared to that at three adjacent National Atmospheric Deposition Program's National Trends Network...
Does food availability affect energy expenditure rates of nesting seabirds? A supplemental-feeding experiment with Black-Legged Kittiwakes (Rissa tridactyla)
Patrick G.R. Jodice, Daniel D. Roby, Scott A. Hatch, Verena A. Gill, Richard B. Lanctot, G. Henk Visser
2002, Canadian Journal of Zoology (80) 214-222
We used a supplemental-feeding experiment, the doubly labeled water technique, and a model-selection approach based upon the Akaike Information Criterion to examine effects of food availability on energy expenditure rates of Black-legged Kittiwakes (Rissa tridactyla) raising young. Energy expenditure rates of supplementally fed females (n = 14) and males (n...
Long-term climate patterns in Alaskan surface temperature and precipitation and their biological consequences
James J. Simpson, Gary L. Hufford, Michael D. Fleming, Jared S. Berg, J.B. Ashton
2002, IEEE Transactions on Geoscience and Remote Sensing (40) 1164-1184
Mean monthly climate maps of Alaskan surface temperature and precipitation produced by the parameter-elevation regression on independent slopes model (PRISM) were analyzed. Alaska is divided into interior and coastal zones with consistent but different climatic variability separated by a transition region; it has maximum interannual variability but low long-term mean...
Source of solutes to the coastal sabkha of Abu Dhabi
W.W. Wood, W. E. Sanford, A.R.S. Al Habshi
2002, Geological Society of America Bulletin (114) 259-268
An ascending-brine model is proposed to address the observed isotope geochemistry, solute composition, and solute and water fluxes in the coastal sabkha of the Emirate of Abu Dhabi. Mass-balance measurements document that >95% of the solutes are derived from ascending continental brines; minor amounts are derived from rainfall and from...
Complex earthquake rupture and local tsunamis
Eric L Geist
2002, Journal of Geophysical Research B: Solid Earth (107) ESE 2-1-ESE 2-15
In contrast to far-field tsunami amplitudes that are fairly well predicted by the seismic moment of subduction zone earthquakes, there exists significant variation in the scaling of local tsunami amplitude with respect to seismic moment. From a global catalog of tsunami runup observations this variability is greatest for the most...
Uranium-series disequilibrium in tuffs from Yucca Mountain, Nevada, as evidence of pore-fluid flow over the last million years
M. Gascoyne, N.H. Miller, L.A. Neymark
2002, Applied Geochemistry (17) 781-792
Samples of tuff from boreholes drilled into fault zones in the Exploratory Studies Facility (ESF) and relatively unfractured rock of the Cross Drift tunnels, at Yucca Mountain, Nevada, have been analysed by U-series methods. This work is part of a project to verify the finding of fast flow-paths through the...
U-Pb ages of secondary silica at Yucca Mountain, Nevada: Implications for the paleohydrology of the unsaturated zone
L.A. Neymark, Y. Amelin, J.B. Paces, Z. E. Peterman
2002, Applied Geochemistry (17) 709-734
Uranium, Th and Pb isotopes were analyzed in layers of opal and chalcedony from individual mm- to cm-thick calcite and silica coatings at Yucca Mountain, Nevada, USA, a site that is being evaluated for a potential high-level nuclear waste repository. These calcite and silica coatings on fractures and in lithophysal...
The western pond turtle (Clemmys marmorata) in the Mojave River, California, USA: Highly adapted survivor or tenuous relict?
J. Lovich, K. Meyer
2002, Journal of Zoology (256) 537-545
Aspects of the ecology of populations of the western pond turtle Clemmys marmorata were investigated in the Mojave River of the central Mojave Desert, California, U.S.A. One population occupied man-made ponds and the other occurred in natural ponds in the flood plain of the Mojave River. Both habitats are severely degraded as...
Dynamic fuzzy modeling of storm water infiltration in urban fractured aquifers
Y.-S. Hong, Michael R. Rosen, R.R. Reeves
2002, Journal of Hydrologic Engineering (7) 380-391
In an urban fractured-rock aquifer in the Mt. Eden area of Auckland, New Zealand, disposal of storm water is via "soakholes" drilled directly into the top of the fractured basalt rock. The dynamic response of the groundwater level due to the storm water infiltration shows characteristics of a strongly time-varying...
Impacts of climate change on the global forest sector
J. Perez-Garcia, L.A. Joyce, A. D. McGuire, X. Xiao
2002, Climatic Change (54) 439-461
The path and magnitude of future anthropogenic emissions of carbon dioxide will likely influence changes in climate that may impact the global forest sector. These responses in the global forest sector may have implications for international efforts to stabilize the atmospheric concentration of carbon dioxide. This study takes a step...
Archiving, processing, and disseminating ASTER products at the USGS EROS Data Center
Brenda Jones, Brian L. Tolk
Barnes W.L., editor(s)
2002, Conference Paper
The U.S. Geological Survey EROS Data Center archives, processes, and disseminates Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data products. The ASTER instrument is one of five sensors onboard the Earth Observing System's Terra satellite launched December 18, 1999. ASTER collects broad spectral coverage with high spatial resolution at...
Paleoseismic event dating and the conditional probability of large earthquakes on the southern San Andreas fault, California
G. P. Biasi, R.J. Weldon II, T. E. Fumal, G. G. Seitz
2002, Bulletin of the Seismological Society of America (92) 2761-2781
We introduce a quantitative approach to paleoearthquake dating and apply it to paleoseismic data from the Wrightwood and Pallett Creek sites on the southern San Andreas fault. We illustrate how stratigraphic ordering, sedimentological, and historical data can be used quantitatively in the process of estimating earthquake ages. Calibrated radiocarbon age...
Historical and modern distributions of benthic foraminifers on the continental shelf of Monterey Bay, California
M. McGann
2002, Marine Geology (181) 115-156
Historical (early 1930s) and modern samples provide a detailed account of the spatial distribution of benthic foraminifers on the continental shelf of Monterey Bay, California. Ten species among a total of 110 present dominated the 110 samples investigated in the historical study. A cluster analysis of the foraminiferal abundances in...
Key Largo Limestone revisited: Pleistocene shelf-edge facies, Florida Keys, USA
Multer H. Gray, E. Gischler, J. Lundberg, K. R. Simmons, E.A. Shinn
2002, Facies 229-272
New dates and analysis of 12 deep and 57 shallow cores allow a more detailed interpretation of the Pleistocene shelf edge of the Florida Platform as found in various facies of the Key Largo Limestone beneath the Florida Keys. In this study a three-phase evolution of the Quaternary units (Q1-Q5)...
