Regional landslide-hazard assessment for Seattle, Washington, USA
R.L. Baum, J. A. Coe, J. W. Godt, E. L. Harp, M.E. Reid, W. Z. Savage, W.H. Schulz, D.L. Brien, A.F. Chleborad, J.P. McKenna, J. A. Michael
2005, Landslides (2) 266-279
Landslides are a widespread, frequent, and costly hazard in Seattle and the Puget Sound area of Washington State, USA. Shallow earth slides triggered by heavy rainfall are the most common type of landslide in the area; many transform into debris flows and cause significant property damage or disrupt transportation. Large...
Debris-bed friction of hard-bedded glaciers
D. Cohen, N.R. Iverson, T.S. Hooyer, U.H. Fischer, M. Jackson, P.L. Moore
2005, Journal of Geophysical Research F: Earth Surface (110)
[1] Field measurements of debris-bed friction on a smooth rock tablet at the bed of Engabreen, a hard-bedded, temperate glacier in northern Norway, indicated that basal ice containing 10% debris by volume exerted local shear traction of up to 500 kPa. The corresponding bulk friction coefficient between the dirty basal...
Application of acoustic doppler current profilers for measuring three-dimensional flow fields and as a surrogate measurement of bedload transport
Jeffrey S. Conaway
2005, Conference Paper, World Water Congress 2005: Impacts of Global Climate Change - Proceedings of the 2005 World Water and Environmental Resources Congress
Acoustic Doppler current profilers (ADCPs) have been in use in the riverine environment for nearly 20 years. Their application primarily has been focused on the measurement of streamflow discharge. ADCPs emit high-frequency sound pulses and receive reflected sound echoes from sediment particles in the water column. The Doppler shift between...
Estimation of streamflow, base flow, and nitrate-nitrogen loads in Iowa using multiple linear regression models
Keith E. Schilling, Calvin F. Wolter
2005, Journal of the American Water Resources Association (41) 1333-1346
Nineteen variables, including precipitation, soils and geology, land use, and basin morphologic characteristics, were evaluated to develop Iowa regression models to predict total streamflow (Q), base flow (Qb), storm flow (Qs) and base flow percentage (%Qb) in gauged and ungauged watersheds in the state. Discharge records from a set of...
Estimation of regional material yield from coastal landslides based on historical digital terrain modelling
C.J. Hapke
2005, Earth Surface Processes and Landforms (30) 679-697
High-resolution historical (1942) and recent (1994) digital terrain models were derived from aerial photographs along the Big Sur coastline in central California to measure the long-term volume of material that enters the nearshore environment. During the 52-year measurement time period, an average of 21 000 ?? 3100 m3 km-1 a-1...
Acute and chronic toxicity of lead in water and diet to the amphipod Hyalella azteca
J.M. Besser, W. G. Brumbaugh, E.L. Brunson, C.G. Ingersoll
2005, Environmental Toxicology and Chemistry (24) 1807-1815
We evaluated the influence of waterborne and dietary lead (Pb) exposure on the acute and chronic toxicity of Pb to the amphipod Hyalella azteca. Test solutions were generated by a modified diluter with an extended (24‐h) equilibration period. Acute (96‐h) toxicity of Pb varied with water hardness...
Holocene and latest Pleistocene oblique dextral faulting on the southern Inyo Mountains fault, Owens Lake basin, California
S.N. Bacon, A. S. Jayko, J. P. McGeehin
2005, Bulletin of the Seismological Society of America (95) 2472-2485
The Inyo Mountains fault (IMF) is a more or less continuous range-front fault system, with discontinuous late Quaternary activity, at the western base of the Inyo Mountains in Owens Valley, California. The southern section of the IMF trends ???N20??-40?? W for at least 12 km at the base of and...
Fish assemblage responses to urban intensity gradients in contrasting metropolitan areas: Birmingham, Alabama and Boston, Massachusetts
M. R. Meador, J.F. Coles, H. Zappia
2005, American Fisheries Society Symposium (2005) 409-423
We examined fish assemblage responses to urban intensify gradients in two contrasting metropolitan areas: Birmingham, Alabama (BIR) and Boston, Massachusetts (BOS). Urbanization was quantified by using an urban intensity index (UII) that included multiple stream buffers and basin land uses, human population density, and road density variables. We evaluated fish...
Critical shear stress for erosion of cohesive soils subjected to temperatures typical of wildfires
J. A. Moody, Smith J. Dungan, B.W. Ragan
2005, Journal of Geophysical Research F: Earth Surface (110)
[1] Increased erosion is a well-known response after wildfire. To predict and to model erosion on a landscape scale requires knowledge of the critical shear stress for the initiation of motion of soil particles. As this soil property is temperature-dependent, a quantitative relation between critical shear stress and the temperatures...
Geomorphic control of radionuclide diffusion in desert soils
J.D. Pelletier, C.D. Harrington, J.W. Whitney, M. Cline, S.B. DeLong, G. Keating, T.K. Ebert
2005, Geophysical Research Letters (32) 1-4
Diffusion is a standard model for the vertical migration of radionuclides in soil profiles. Here we show that diffusivity values inferred from fallout 137CS profiles in soils on the Fortymile Wash alluvial fan, Nye County, Nevada, have a strong inverse correlation with the age of the geomorphic surface. This result...
Ice elevations and surface change on the Malaspina Glacier, Alaska
J. Sauber, B. Molnia, C. Carabajal, S. Luthcke, R. Muskett
2005, Geophysical Research Letters (32) 1-4
Here we use Ice, Cloud and land Elevation Satellite (ICESat)-derived elevations and surface characteristics to investigate the Malaspina Glacier of southern Alaska. Although there is significant elevation variability between ICESat tracks on this glacier, we were able to discern general patterns in surface elevation change by using a regional digital...
The wrinkle-like slip pulse is not important in earthquake dynamics
D.J. Andrews, R.A. Harris
2005, Geophysical Research Letters (32) 1-4
A particular solution for slip on an interface between different elastic materials, the wrinkle-like slip pulse, propagates in only one direction with reduced normal compressive stress. More general solutions, and natural earthquakes, need not share those properties. In a 3D dynamic model with a drop in friction and heterogeneous initial...
Nature's style: Naturally trendy
T.A. Cohn, H.F. Lins
2005, Geophysical Research Letters (32) 1-5
Hydroclimatological time series often exhibit trends. While trend magnitude can be determined with little ambiguity, the corresponding statistical significance, sometimes cited to bolster scientific and political argument, is less certain because significance depends critically on the null hypothesis which in turn reflects subjective notions about what one expects to see....
DEM, tide and velocity over sulzberger ice shelf, West Antarctica
S. Baek, C. K. Shum, H. Lee, Y. Yi, Oh-Ig Kwoun, Z. Lu, Andreas Braun
2005, Conference Paper, International Geoscience and Remote Sensing Symposium (IGARSS) proceedings
Arctic and Antarctic ice sheets preserve more than 77% of the global fresh water and could raise global sea level by several meters if completely melted. Ocean tides near and under ice shelves shifts the grounding line position significantly and are one of current limitations to study glacier dynamics and...
Suburban wildlife: Lessons, challenges, and opportunities
S. DeStefano, R.D. Deblinger, C. Miller
2005, Urban Ecosystems (8) 131-137
The United States, as well as most developed and many developing nations worldwide, is becoming increasingly urban and suburban.Although urban, suburban, and commercial development account for less than one percent to just over 20% of land use among states, 50-90% of the residents of those states can be classified as...
Regulation of landslide motion by dilatancy and pore pressure feedback
R.M. Iverson
2005, Journal of Geophysical Research F: Earth Surface (110)
A new mathematical model clarifies how diverse styles and rates of landslide motion can result from regulation of Coulomb friction by dilation or contraction of water‐saturated basal shear zones. Normalization of the model equations shows that feedback due to coupling between landslide motion, shear zone volume change, and pore pressure...
Heat as a tracer to estimate dissolved organic carbon flux from a restored wetland
K.R. Burow, J. Constantz, R. Fujii
2005, Ground Water (43) 545-556
Heat was used as a natural tracer to characterize shallow ground water flow beneath a complex wetland system. Hydrogeologic data were combined with measured vertical temperature profiles to constrain a series of two‐dimensional, transient simulations of ground water flow and heat transport using the model code...
The evolution of vertebrate Toll-like receptors
J.C. Roach, G. Glusman, L. Rowen, A. Kaur, M. K. Purcell, K.D. Smith, L.E. Hood, A. Aderem
2005, Proceedings of the National Academy of Sciences of the United States of America (102) 9577-9582
The complete sequences of Takifugu Toll-like receptor (TLR) loci and gene predictions from many draft genomes enable comprehensive molecular phylogenetic analysis. Strong selective pressure for recognition of and response to pathogen-associated molecular patterns has maintained a largely unchanging TLR recognition in all vertebrates. There are six major families of vertebrate...
Disturbance frequency and community structure in a twenty-five year intervention study
J.C. Trexler, W.F. Loftus, S. Perry
2005, Oecologia (145) 140-152
Models of community regulation commonly incorporate gradients of disturbance inversely related to the role of biotic interactions in regulating intermediate trophic levels. Higher trophic-level organisms are predicted to be more strongly limited by intermediate levels of disturbance than are the organisms they consume. We used a manipulation of the frequency...
New surveys of the Chesapeake Bay impact structure suggest melt pockets and target-structure effect
A. K. Shah, J. Brozena, P. Vogt, D. Daniels, J. Plescia
2005, Geology (33) 417-420
We present high-resolution gravity and magnetic field survey results over the 85-km-diameter Chesapeake Bay impact structure. Whereas a continuous melt sheet is anticipated at a crater this size, shallow-source magnetic field anomalies of ???100 nT instead suggest that impact melt pooled in kilometer-scaled pockets surrounding the base of a central...
Conceptual model of sediment processes in the upper Yuba River watershed, Sierra Nevada, CA
Jennifer A. Curtis, Lorraine E. Flint, Charles N. Alpers, S.M. Yarnell
2005, Geomorphology (68) 149-166
This study examines the development of a conceptual model of sediment processes in the upper Yuba River watershed; and we hypothesize how components of the conceptual model may be spatially distributed using a geographical information system (GIS). The conceptual model illustrates key processes controlling sediment dynamics in the upper Yuba...
Simulating the evolution of coastal morphology and stratigraphy with a new morphological-behaviour model (GEOMBEST)
D. Stolper, J. H. List, E.R. Thieler
2005, Marine Geology (218) 17-36
A new morphological-behaviour model is used to simulate evolution of coastal morphology associated with cross-shore translations of the shoreface, barrier, and estuary. The model encapsulates qualitative principles drawn from established geological concepts that are parameterized to provide quantitative predictions of morphological change on geological time scales (order 10 3 years),...
Source mechanism of Vulcanian degassing at Popocatépetl Volcano, Mexico, determined from waveform inversions of very long period signals
Bernard A. Chouet, Phillip B. Dawson, Alejandra Arciniega-Ceballos
2005, Journal of Geophysical Research B: Solid Earth (110) 1-20
The source mechanism of very long period (VLP) signals accompanying volcanic degassing bursts at Popocatépetl is analyzed in the 15–70 s band by minimizing the residual error between data and synthetics calculated for a point source embedded in a homogeneous medium. The waveforms of two eruptions (23 April and 23...
Sources, bioavailability, and photoreactivity of dissolved organic carbon in the Sacramento-San Joaquin River Delta
R. Stepanauskas, M.A. Moran, B.A. Bergamaschi, J.T. Hollibaugh
2005, Biogeochemistry (74) 131-149
We analyzed bioavailability, photoreactivity, fluorescence, and isotopic composition of dissolved organic carbon (DOC) collected at 13 stations in the Sacramento-San Joaquin River Delta during various seasons to estimate the persistence of DOC from diverse shallow water habitat sources. Prospective large-scale wetland restorations in the Delta may change the amount of...
Spatial and temporal use of a spawning site in the middle green river by wild and hatchery-reared razorback suckers
T. Modde, Z.H. Bowen, D.C. Kitcheyan
2005, Transactions of the American Fisheries Society (134) 937-944
The population of endangered razorback suckers Xyrauchen texanus in the middle Green River (upper Colorado River basin) has declined during the last 40 years. The apparent cause for this decline is a lack of successful recruitment. This study used radiotelemetry to evaluate the ability of hatchery-reared razorback suckers to locate...
