Laboratory and field testing of commercial rotational seismometers
R.L. Nigbor, J.R. Evans, C. R. Hutt
2009, Bulletin of the Seismological Society of America (99) 1215-1227
There are a small number of commercially available sensors to measure rotational motion in the frequency and amplitude ranges appropriate for earthquake motions on the ground and in structures. However, the performance of these rotational seismometers has not been rigorously and independently tested and characterized for earthquake monitoring purposes as...
Spatial and temporal distributions of Martian north polar cold spots before, during, and after the global dust storm of 2001
C. Cornwall, T.N. Titus
2009, Journal of Geophysical Research E: Planets (114)
In the 1970s, Mariner and Viking observed features in the Mars northern polar region that were a few hundred kilometers in diameter with 20 fj,m brightness temperatures as low as 130 K (considerably below C02 ice sublimation temperatures). Over the past decade, studies have shown that these areas (commonly called...
Untangling the biological contributions to soil stability in semiarid shrublands
V. Bala Chaudhary, Matthew A. Bowker, Thomas E. O’Dell, James B. Grace, Andrea E. Redman, Matthias C. Rillig, Nancy C. Johnson
2009, Ecological Applications (19) 110-122
Communities of plants, biological soil crusts (BSCs), and arbuscular mycorrhizal (AM) fungi are known to influence soil stability individually, but their relative contributions, interactions, and combined effects are not well understood, particularly in arid and semiarid ecosystems. In a landscape-scale field study we quantified plant, BSC, and AM fungal communities...
Calibration and validation of the relative differenced Normalized Burn Ratio (RdNBR) to three measures of fire severity in the Sierra Nevada and Klamath Mountains, California, USA
J.D. Miller, E. E. Knapp, C.H. Key, C.N. Skinner, C.J. Isbell, R.M. Creasy, J.W. Sherlock
2009, Remote Sensing of Environment (113) 645-656
Multispectral satellite data have become a common tool used in the mapping of wildland fire effects. Fire severity, defined as the degree to which a site has been altered, is often the variable mapped. The Normalized Burn Ratio (NBR) used in an absolute difference change detection protocol (dNBR), has become...
Uniform California earthquake rupture forecast, version 2 (UCERF 2)
E. H. Field, T. E. Dawson, K.R. Felzer, A.D. Frankel, V. Gupta, T.H. Jordan, T. Parsons, M.D. Petersen, R.S. Stein, R. J. Weldon, C.J. Wills
2009, Bulletin of the Seismological Society of America (99) 2053-2107
The 2007 Working Group on California Earthquake Probabilities (WGCEP, 2007) presents the Uniform California Earthquake Rupture Forecast, Version 2 (UCERF 2). This model comprises a time-independent (Poisson-process) earthquake rate model, developed jointly with the National Seismic Hazard Mapping Program and a time-dependent earthquake-probability model, based on recent earthquake rates and...
Combining particle-tracking and geochemical data to assess public supply well vulnerability to arsenic and uranium
S.R. Hinkle, L. J. Kauffman, M.A. Thomas, C. J. Brown, K. A. McCarthy, S. M. Eberts, Michael R. Rosen, B. G. Katz
2009, Journal of Hydrology (376) 132-142
Flow-model particle-tracking results and geochemical data from seven study areas across the United States were analyzed using three statistical methods to test the hypothesis that these variables can successfully be used to assess public supply well vulnerability to arsenic and uranium. Principal components analysis indicated that arsenic and uranium concentrations...
Characterization of phyllosilicates observed in the central Mawrth Vallis region, Mars, their potential formational processes, and implications for past climate
N.K. McKeown, J.L. Bishop, E.Z. Noe Dobrea, B.L. Ehlmann, M. Parente, J.F. Mustard, S.L. Murchie, G.A. Swayze, J.-P. Bibring, E. A. Silver
2009, Journal of Geophysical Research E: Planets (114)
Mawrth Vallis contains one of the largest exposures of phyllosilicates on Mars. Nontronite, montmorillonite, kaolinite, and hydrated silica have been identified throughout the region using data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). In addition, saponite has been identified in one observation within a crater. These individual minerals...
Small-footprint, waveform-resolving lidar estimation of submerged and sub-canopy topography in coastal environments
A. Nayegandhi, J. C. Brock, C. W. Wright
2009, International Journal of Remote Sensing (30) 861-878
The experimental advanced airborne research lidar (EAARL) is an airborne lidar instrument designed to map near-shore submerged topography and adjacent land elevations simultaneously. This study evaluated data acquired by the EAARL system in February 2003 and March 2004 along the margins of Tampa Bay, Florida, USA, to map bare-earth elevations...
Kolmogorov-Smirnov test for spatially correlated data
Ricardo A. Olea, V. Pawlowsky-Glahn
2009, Stochastic Environmental Research and Risk Assessment (23) 749-757
The Kolmogorov-Smirnov test is a convenient method for investigating whether two underlying univariate probability distributions can be regarded as undistinguishable from each other or whether an underlying probability distribution differs from a hypothesized distribution. Application of the test requires that the sample be unbiased and the outcomes be independent and...
In-Flight performance of MESSENGER's Mercury dual imaging system
S.E. Hawkins, S.L. Murchie, K.J. Becker, C.M. Selby, F.S. Turner, M.W. Noble, N.L. Chabot, T.H. Choo, E.H. Darlington, B.W. Denevi, D.L. Domingue, C.M. Ernst, G.M. Holsclaw, N.R. Laslo, W.E. Mcclintock, L.M. Prockter, M.S. Robinson, S.C. Solomon, R.E. Sterner
2009, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
The Mercury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched in August 2004 and planned for insertion into orbit around Mercury in 2011, has already completed two flybys of the innermost planet. The Mercury Dual Imaging System (MDIS) acquired nearly 2500 images from the first two flybys and viewed...
Quantifying uncertainty in discharge measurements: A new approach
J.E. Kiang, T.A. Cohn, R.R. Mason
2009, Conference Paper, Proceedings of World Environmental and Water Resources Congress 2009 - World Environmental and Water Resources Congress 2009: Great Rivers
The accuracy of discharge measurements using velocity meters and the velocity-area method is typically assessed based on empirical studies that may not correspond to conditions encountered in practice. In this paper, a statistical approach for assessing uncertainty based on interpolated variance estimation (IVE) is introduced. The IVE method quantifies all...
Improved constraints on the estimated size and volatile content of the Mount St. Helens magma system from the 2004-2008 history of dome growth and deformation
L.G. Mastin, M. Lisowski, E. Roeloffs, N. Beeler
2009, Geophysical Research Letters (36)
The history of dome growth and geodetic deflation during the 2004-2008 Mount St. Helens eruption can be fit to theoretical curves with parameters such as reservoir volume, bubble content, initial overpressure, and magma rheology, here assumed to be Newtonian viscous, with or without a solid plug in the conduit center....
A calibrated, high-resolution goes satellite solar insolation product for a climatology of Florida evapotranspiration
S.J. Paech, J.R. Mecikalski, D. M. Sumner, C.S. Pathak, Q. Wu, S. Islam, T. Sangoyomi
2009, Journal of the American Water Resources Association (45) 1328-1342
Estimates of incoming solar radiation (insolation) from Geostationary Operational Environmental Satellite observations have been produced for the state of Florida over a 10-year period (1995-2004). These insolation estimates were developed into well-calibrated half-hourly and daily integrated solar insolation fields over the state at 2 km resolution, in addition to a...
Delayed conifer mortality after fuel reduction treatments: Interactive effects of fuel, fire intensity, and bark beetles
A. Youngblood, J.B. Grace, J.D. Mciver
2009, Ecological Applications (19) 321-337
Many low‐elevation dry forests of the western United States contain more small trees and fewer large trees, more down woody debris, and less diverse and vigorous understory plant communities compared to conditions under historical fire regimes. These altered structural conditions may contribute to increased probability of unnaturally severe wildfires, susceptibility...
A less field-intensive robust design for estimating demographic parameters with Mark-resight data
B.T. McClintock, Gary C. White
2009, Ecology (90) 313-320
The robust design has become popular among animal ecologists as a means for estimating population abundance and related demographic parameters with mark-recapture data. However, two drawbacks of traditional mark-recapture are financial cost and repeated disturbance to animals. Mark-resight methodology may in many circumstances be a less expensive and less invasive...
Genetic susceptibility to chronic wasting disease in free-ranging white-tailed deer: complement component C1q and Prnp polymorphisms
Julie A. Blanchong, Dennis M. Heisey, Kim T. Scribner, Scot V. Libants, Chad Johnson, Judd M. Aiken, Julia A. Langenberg, Michael D. Samuel
2009, Infection, Genetics and Evolution (9) 1329-1335
The genetic basis of susceptibility to chronic wasting disease (CWD) in free-ranging cervids is of great interest. Association studies of disease susceptibility in free-ranging populations, however, face considerable challenges including: the need for large sample sizes when disease is rare, animals of unknown pedigree create a risk of spurious results...
Promoting species establishment in a phragmites-dominated great lakes coastal wetland
M.L. Carlson, K.P. Kowalski, D.A. Wilcox
2009, Natural Areas Journal (29) 263-280
This study examined efforts to promote species establishment and maintain diversity in a Phragmites-dominated wetland where primary control measures were underway. A treatment experiment was performed at Crane Creek, a drowned-river-mouth wetland in Ottawa National Wildlife Refuge along the shore of western Lake Erie. Following initial aerial spraying of Phragmites...
Negligible influence of spatial autocorrelation in the assessment of fire effects in a mixed conifer forest
P. J. van Mantgem, D.W. Schwilk
2009, Fire Ecology (5) 116-125
Fire is an important feature of many forest ecosystems, although the quantification of its effects is compromised by the large scale at which fire occurs and its inherent unpredictability. A recurring problem is the use of subsamples collected within individual burns, potentially resulting in spatially autocorrelated data. Using subsamples from...
Spatial-temporal patterns in Mediterranean carnivore road casualties: Consequences for mitigation
C. Grilo, J.A. Bissonette, M. Santos-Reis
2009, Biological Conservation (142) 301-313
Many carnivores have been seriously impacted by the expansion of transportation systems and networks; however we know little about carnivore response to the extent and magnitude of road mortality, or which age classes may be disproportionately impacted. Recent research has demonstrated that wildlife-vehicle-collisions (WVC) involving carnivores are modulated by temporal...
Numerical analysis of the performance of rock weirs: Effects of structure configuration on local hydraulics
C. L. Holmquist-Johnson
2009, Conference Paper, Proceedings of World Environmental and Water Resources Congress 2009 - World Environmental and Water Resources Congress 2009: Great Rivers
River spanning rock structures are being constructed for water delivery as well as to enable fish passage at barriers and provide or improve the aquatic habitat for endangered fish species. Current design methods are based upon anecdotal information applicable to a narrow range of channel conditions. The complex flow patterns...
Research on the middle-of-receiver-spread assumption of the MASW method
Y. Luo, J. Xia, J. Liu, Y. Xu, Q. Liu
2009, Soil Dynamics and Earthquake Engineering (29) 71-79
The multichannel analysis of surface wave (MASW) method has been effectively used to determine near-surface shear- (S-) wave velocity. Estimating the S-wave velocity profile from Rayleigh-wave measurements is straightforward. A three-step process is required to obtain S-wave velocity profiles: acquisition of a multiple number of multichannel records along a linear...
Characterizing and predicting species distributions across environments and scales: Argentine ant occurrences in the eye of the beholder
S.B. Menke, D.A. Holway, Robert N. Fisher, W. Jetz
2009, Global Ecology and Biogeography (18) 50-63
Aim: Species distribution models (SDMs) or, more specifically, ecological niche models (ENMs) are a useful and rapidly proliferating tool in ecology and global change biology. ENMs attempt to capture associations between a species and its environment and are often used to draw biological inferences, to predict potential occurrences in unoccupied...
Hydrologic and biogeochemical controls of river subsurface solutes under agriculturally enhanced ground water flow
R.A. Wildman Jr., Joseph L. Domagalski, J. G. Hering
2009, Journal of Environmental Quality (38) 1830-1840
The relative influences of hydrologic processes and biogeochemistry on the transport and retention of minor solutes were compared in the riverbed of the lower Merced River (California, USA). The subsurface of this reach receives ground water discharge and surface water infiltration due to an altered hydraulic setting resulting from agricultural...
Using "big data" to optimally model hydrology and water quality across expansive regions
E.A. Roehl Jr., J.B. Cook, P.A. Conrads
2009, Conference Paper, Proceedings of World Environmental and Water Resources Congress 2009 - World Environmental and Water Resources Congress 2009: Great Rivers
This paper describes a new divide and conquer approach that leverages big environmental data, utilizing all available categorical and time-series data without subjectivity, to empirically model hydrologic and water-quality behaviors across expansive regions. The approach decomposes large, intractable problems into smaller ones that are optimally solved; decomposes complex signals into...
Extraction of lidar-based dune-crest elevations for use in examining the vulnerability of beaches to inundation during hurricanes
H.F. Stockdon, K.S. Doran, A. H. Sallenger Jr.
2009, Journal of Coastal Research 59-65
The morphology of coastal sand dunes plays an important role in determining how a beach will respond to a hurricane. Accurate measurements of dune height and position are essential for assessing the vulnerability of beaches to extreme coastal change during future landfalls. Lidar topographic surveys provide rapid, accurate, high-resolution datasets...