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Utah State University

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2010

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Cosmic Voices: Searching For Signs Of Life Elsewhere In The Universe, Shane L. Larson Dec 2010

Cosmic Voices: Searching For Signs Of Life Elsewhere In The Universe, Shane L. Larson

Public Talks

No abstract provided.


Uncertainty Associated With Modeling The Global Ionosphere, Janelle V. Jenniges, Ariel O. Acebal, Larry Gardner, Robert W. Schunk, Lie Zhu Dec 2010

Uncertainty Associated With Modeling The Global Ionosphere, Janelle V. Jenniges, Ariel O. Acebal, Larry Gardner, Robert W. Schunk, Lie Zhu

Physics Student Research

A study has been conducted of the effect that different physical assumptions have on global models of the electron density distribution. The study was conducted with the Ionosphere Forecast Model (IFM) and the Ionosphere Plasmasphere Model (IPM) developed by Utah State University. Both physics-based, time-dependent, global models use the same empirical models for the neutral atmosphere (MSIS) and neutral wind (Horizontal Wind Model, HWM), but the altitude range, thermal structure, number of ion species, and magnetic 2ield are different. The IFM covers the altitude range from 90-1400 km, calculates the densities for four ions (NO+, O2+, N2+, O+), has a …


Rock Properties And Internal Structure Of The San Andreas Fault Near ~ 3 Km Depth In The Safod Borehole Based On Meso- To Micro-Scale Analyses Of Phase Iii Whole Rock Core, Kelly Keighley Bradbury, James P. Evans Dec 2010

Rock Properties And Internal Structure Of The San Andreas Fault Near ~ 3 Km Depth In The Safod Borehole Based On Meso- To Micro-Scale Analyses Of Phase Iii Whole Rock Core, Kelly Keighley Bradbury, James P. Evans

Geosciences Presentations

We examine the relationships between rock properties and structure within ~ 41 m of PHASE III whole-rock core collected from ~ 3 km depth along the SAF in the San Andreas Fault Observatory at Depth (SAFOD) borehole, near Parkfield, CA.


Quasi-Decadal Spectral Peaks Of Tropical Western Pacific Ssts As A Precursor For Tropical Cyclone Threat, Shih-Yu (Simon) Wang, Adam J. Clark Nov 2010

Quasi-Decadal Spectral Peaks Of Tropical Western Pacific Ssts As A Precursor For Tropical Cyclone Threat, Shih-Yu (Simon) Wang, Adam J. Clark

Plants, Soils, and Climate Faculty Publications

A recent study identified significant spectral peaks in sea surface temperatures (SSTs) at quasi‐decadal frequency bands, which were unique to the tropical western Pacific (TWP). Using the multitaper method for spectral and coherence analysis, this study finds that the TWP SSTs at these quasi‐decadal time scales are coherent with western Pacific tropical cyclone threat [as measured by the power dissipation index (PDI)], but that the PDI lags TWP SSTs by about two years. Thus, the quasi‐decadal peaks in TWP SSTs may be a precursor for enhanced tropical cyclone threat two years later. Composite analyses are shown to illustrate how areal …


Oh And Oi Airglow Layer Modulation By Ducted Shortperiod Gravity Waves: Effects Of Trapping Altitude, J. B. Snively, V. P. Pasko, Michael J. Taylor Nov 2010

Oh And Oi Airglow Layer Modulation By Ducted Shortperiod Gravity Waves: Effects Of Trapping Altitude, J. B. Snively, V. P. Pasko, Michael J. Taylor

All Physics Faculty Publications

Perturbations to the OH and OI [O(1S) 557.7 nm] airglow layers by ducted gravity waves near the Brunt-Väisälä period are investigated using a 2-D numerical model. Airglow signatures of these waves are strongly determined by perturbations of O, O3, and H, which exhibit peak densities near and above mesopause. Strong periodic vertical wind components of short-period gravity waves induce opposite relative density perturbations above and below the layer density peaks. Airglow signatures for ducted waves depend on the specific vertical shapes and altitudes of the wave packets relative to ambient species density profiles; waves perturbing …


Characterization Of Pollen Particles Using Lidar, Leda Sox Oct 2010

Characterization Of Pollen Particles Using Lidar, Leda Sox

Graduate Student Posters

We have observed pollen in the local troposphere using the depolarization capabilities of a LIDAR (Light Detection and Ranging) system. The polarization characteristics of the received LIDAR signal, along with supplemental pollen forecast data, allowed me to characterize the shape of the pollen particles.


Predator Functional Response Changed By Induced Defenses In Prey, Edd Hammill, Owen L. Petchey, Bradley R. Anholt Oct 2010

Predator Functional Response Changed By Induced Defenses In Prey, Edd Hammill, Owen L. Petchey, Bradley R. Anholt

Watershed Sciences Faculty Publications

Functional responses play a central role in the nature and stability of predator‐prey population dynamics. Here we investigate how induced defenses affect predator functional responses. In experimental communities, prey (Paramecium) expressed two previously undocumented inducible defenses—a speed reduction and a width increase—in response to nonlethal exposure to predatory Stenostomum. Nonlethal exposure also changed the shape of the predator’s functional response from Type II to Type III, consistent with changes in the density dependence of attack rates. Handling times were also affected by prey defenses, increasing at least sixfold. These changes show that induced changes in prey have a real defensive …


The First Ten Months Of Investigation Of Gravity Waves And Temperature Variability Over The Andes, Jonathan Pugmire, Neal Criddle, Michael J. Taylor, P. D. Pautet, Yucheng Zhao Oct 2010

The First Ten Months Of Investigation Of Gravity Waves And Temperature Variability Over The Andes, Jonathan Pugmire, Neal Criddle, Michael J. Taylor, P. D. Pautet, Yucheng Zhao

Graduate Student Posters

The Andes region is an excellent natural laboratory for investigating gravity wave influences on the Upper Mesospheric and Lower Thermospheric (MLT) dynamics. The instrument suite that comprised the very successful Maui-MALT program was recently re-located to a new Andes Lidar Observatory (ALO) located at Cerro Pachon, Chile to obtain in-depth seasonal measurements of MLT dynamics over the Andes mountains. As part of the instrument set the Utah State University CEDAR Mesospheric Temperature Mapper (MTM) has operated continuously since August 2009 measuring the near infrared OH(6,2) band and the O2(0,1) Atmospheric band intensity and temperature perturbations. This poster focuses on an …


Einstein In The Sky: Black Hole Tales From The Edge Of Space And Time, Shane L. Larson Oct 2010

Einstein In The Sky: Black Hole Tales From The Edge Of Space And Time, Shane L. Larson

Public Talks

No abstract provided.


First Year Investigation Of Gravity Waves And Temperature Variability Over The Andes, Jonathan Pugmire, Neal R. Criddle, Michael J. Taylor, Dominique Pautet, Yucheng Zhao Oct 2010

First Year Investigation Of Gravity Waves And Temperature Variability Over The Andes, Jonathan Pugmire, Neal R. Criddle, Michael J. Taylor, Dominique Pautet, Yucheng Zhao

Graduate Student Presentations

The Andes region is an excellent natural laboratory for investigating gravity wave influences on the Upper Mesospheric and Lower Thermospheric (MLT) dynamics: during the summer months the dominant gravity waves result from deep convection arising from severe thunderstorms over the continent to the east. In winter this convective activity is expected to be replaced by strong orographic forcing due to intense prevailing zonal winds blowing eastward from the Pacific Ocean and suddenly encountering the towering Andes mountain range (6000m). This creates large amplitude mountain waves that have been measured well into the stratosphere and most recently penetrate occasionally into the …


Comparison Of Flight And Ground Tests Of Environmental Degradation Of Misse-6 Suspecs Materials, Jr Dennison, John Prebola, Amberly Evans Jensen, Joshua L. Hodges Sep 2010

Comparison Of Flight And Ground Tests Of Environmental Degradation Of Misse-6 Suspecs Materials, Jr Dennison, John Prebola, Amberly Evans Jensen, Joshua L. Hodges

Conference Proceedings

The effects of prolonged exposure to the LEO space environment and charge-enhanced contamination on optical, thermal, and electron emission and transport properties of common spacecraft materials has been investigated by comparing pre- and post-flight characterization measurements. The State of Utah Space Environment & Contamination Study (SUSpECS) deployed in March 2008 on board the Materials International Space Station Experiment (MISSE-6) payload, was exposed for ~18 months on the exterior of the International Space Station (ISS), before retrieval in September 2009. A total of 165 samples were …


Release Of Mercury Halides From Kcl Denuders In The Presence Of Ozone, Seth N. Lyman, Daniel A. Jaffe, Mae S. Gustin Sep 2010

Release Of Mercury Halides From Kcl Denuders In The Presence Of Ozone, Seth N. Lyman, Daniel A. Jaffe, Mae S. Gustin

USU Uintah Basin Faculty Publications

KCl-coated denuders have become a standard method for measurement of gaseous oxidized mercury, but their performance has not been exhaustively evaluated, especially in field conditions. In this study, KCl-coated and uncoated quartz denuders loaded with HgCl2 and HgBr2 lost 29–55% of these compounds, apparently as elemental mercury, when exposed to ozone (range of 6–100 ppb tested). This effect was also observed for denuders loaded with gaseous oxidized mercury at a field site in Nevada (3–37% of oxidized mercury lost). In addition, collection efficiency decreased by 12–30% for denuders exposed to 50 ppb ozone during collection of HgCl2 …


Earth Systems Lesson Plan: Size And Forces Of The Solar System, Getaway Special Team 2010 Sep 2010

Earth Systems Lesson Plan: Size And Forces Of The Solar System, Getaway Special Team 2010

Education and Outreach

No abstract provided.


Elementary And Middle School Science Lesson Plan: Solid, Liquid, Gas, What Is It?, Getaway Special Team 2010 Sep 2010

Elementary And Middle School Science Lesson Plan: Solid, Liquid, Gas, What Is It?, Getaway Special Team 2010

Education and Outreach

No abstract provided.


Symmetric Criticality In Classical Field Theory, Charles G. Torre, Ian M. Anderson Sep 2010

Symmetric Criticality In Classical Field Theory, Charles G. Torre, Ian M. Anderson

All Physics Faculty Publications

This is a brief overview of work done by Ian Anderson, Mark Fels, and myself on symmetry reduction of Lagrangians and Euler-Lagrange equations, a subject closely related to Palais’ Principle of Symmetric Criticality. After providing a little history, I describe necessary and sufficient conditions on a group action such that reduction of a group-invariant Lagrangian by the symmetry group yields the correct symmetry-reduced Euler-Lagrange equations.


Physics Lesson Plan: How Far And Fast Does It Travel?, Getaway Special Team 2010 Sep 2010

Physics Lesson Plan: How Far And Fast Does It Travel?, Getaway Special Team 2010

Education and Outreach

No abstract provided.


Atmospheric Scale Interaction On Wintertime Intermountain West Low-Level Inversions, Robert R. Gillies, Shih-Yu (Simon) Wang, Marty R. Booth Aug 2010

Atmospheric Scale Interaction On Wintertime Intermountain West Low-Level Inversions, Robert R. Gillies, Shih-Yu (Simon) Wang, Marty R. Booth

Plants, Soils, and Climate Faculty Publications

Persistent winter inversions result in poor air quality in the Intermountain West of the United States. Although the onset of an inversion is relatively easy to predict, the duration and the subsequent breakup of a persistent inversion event remains a forecasting challenge. For this reason and for this region, historic soundings were analyzed for Salt Lake City, Utah, with reanalysis and station data to investigate how persistent inversion events are modulated by synoptic and intraseasonal variabilities. The results point to a close linkage between persistent inversions and the dominant intraseasonal (30 day) mode that characterizes the winter circulation regime over …


Nam Model Forecasts Of Warm Season Quasi-Stationary Frontal Environments In The Central U.S., Shih-Yu (Simon) Wang, Adam J. Clark Aug 2010

Nam Model Forecasts Of Warm Season Quasi-Stationary Frontal Environments In The Central U.S., Shih-Yu (Simon) Wang, Adam J. Clark

Plants, Soils, and Climate Faculty Publications

Using a composite procedure, North American Mesoscale Model (NAM) forecast and observed environments associated with zonally oriented, quasi-stationary surface fronts for 64 cases during July–August 2006–08 were examined for a large region encompassing the central United States. NAM adequately simulated the general synoptic features associated with the frontal environments (e.g., patterns in the low-level wind fields) as well as the positions of the fronts. However, kinematic fields important to frontogenesis such as horizontal deformation and convergence were overpredicted. Surface-based convective available potential energy (CAPE) and precipitable water were also overpredicted, which was likely related to the overprediction of the kinematic …


Cfs Prediction Of Winter Persistent Inversions In The Intermountain Region, Robert R. Gillies, Shih-Yu (Simon) Wang, Jin Ho Yoon, Scott Weaver Aug 2010

Cfs Prediction Of Winter Persistent Inversions In The Intermountain Region, Robert R. Gillies, Shih-Yu (Simon) Wang, Jin Ho Yoon, Scott Weaver

Plants, Soils, and Climate Faculty Publications

A recent study by Gillies and others of persistent inversion events in the Intermountain West of the United States found a substantive linkage between the intraseasonal oscillation (ISO) and the development of persistent inversion events. Given that NCEP’s Climate Forecast System (CFS) has demonstrated skill in the prediction of the ISO as far out as 1 month, it was decided to examine the CFS forecast’s capability in the prediction of such winter persistent inversions. After initial analysis, a simple regression scheme is proposed that is coupled to the CFS output of geopotential height as a way to predict the occurrence …


Environmental Assessment Fontenelle Community Renovation, Seedskadee Project, Lincoln County, Wyoming, United States Department Of The Interior, Bureau Of Reclamation Jul 2010

Environmental Assessment Fontenelle Community Renovation, Seedskadee Project, Lincoln County, Wyoming, United States Department Of The Interior, Bureau Of Reclamation

Environmental Assessments (WY)

The Seedskadee Project is a participating project in the Colorado River Storage Project. Principle features of the project are the Fontenelle Dam, Powerplant, and Reservoir. The project is located on the Green River some 24 miles southeast of LaBarge, Wyoming in Lincoln County. The dam is located at latitude: 42.0285593 - longitude: -110.0604315. The project features, along with worker housing, were built beginning in 1961 and completed in 1964. The houses and associated infrastructure (road) are in need of extensive renovation. Reclamation conducted a value engineering study to review options to meet the need for improved employee housing, and this …


The Cosmos Out Your Back Door, Shane L. Larson Jul 2010

The Cosmos Out Your Back Door, Shane L. Larson

Public Talks

No abstract provided.


Polar Mesospheric Cloud Structures Observed From The Cloud Imaging And Particle Size Experiment On The Aeronomy Of Ice In The Mesosphere Spacecraft: Atmospheric Gravity Waves As Drivers For Longitudinal Variability In Polar Mesospheric Cloud Occurrence, A. Chandran, D. W. Rusch, A. W. Merkel, S. E. Palo, G. E. Thomas, Michael J. Taylor, S. M. Bailey, J. M. Russell Iii Jul 2010

Polar Mesospheric Cloud Structures Observed From The Cloud Imaging And Particle Size Experiment On The Aeronomy Of Ice In The Mesosphere Spacecraft: Atmospheric Gravity Waves As Drivers For Longitudinal Variability In Polar Mesospheric Cloud Occurrence, A. Chandran, D. W. Rusch, A. W. Merkel, S. E. Palo, G. E. Thomas, Michael J. Taylor, S. M. Bailey, J. M. Russell Iii

All Physics Faculty Publications

The cloud imaging and particle size (CIPS) experiment is one of three instruments on board the Aeronomy of Ice in the Mesosphere (AIM) spacecraft that was launched into a 600 km Sun‐synchronous orbit on 25 April 2007. CIPS images have shown distinct wave patterns and structures in polar mesospheric clouds (PMCs), around the summertime mesopause region, which are qualitatively similar to structures seen in noctilucent clouds (NLCs) from ground‐based photographs. The structures in PMC are generally considered to be manifestations of upward propagating atmospheric gravity waves (AGWs). Variability of AGW effects on PMC reported at several lidar sites has led …


A Planetary-Scale Land–Sea Breeze Circulation In East Asia And The Western North Pacific, W. R. Huang, J. C-L Chan, Shih-Yu (Simon) Wang Jul 2010

A Planetary-Scale Land–Sea Breeze Circulation In East Asia And The Western North Pacific, W. R. Huang, J. C-L Chan, Shih-Yu (Simon) Wang

Plants, Soils, and Climate Faculty Publications

The diurnal wind variation over the East Asian continent is commonly considered to be a combination of a land-sea breeze near the coast and a mountain–valley breeze along the slopes of the Tibetan Plateau. The local land–sea breeze along the coastline typically spansHowever, a detailed examination of the global reanalysis data suggests that this local land–sea breeze circulation apparently couples with the global-scale diurnal atmospheric pressure tide to produce a planetary-scale land–sea breeze with a spatial scale of ∼1000 km over the western North Pacific. Computations of the momentum budget and equivalent potential temperatures indicate that the atmospheric diurnal tidal …


Tips To Taper Energy Costs In The Kitchen, Lou Mueller Jul 2010

Tips To Taper Energy Costs In The Kitchen, Lou Mueller

All Current Publications

This publications gives suggestions on how to save on energy costs in the kitchen.


Making A Big Bang: Understanding The Observable Universe, Shane L. Larson Jun 2010

Making A Big Bang: Understanding The Observable Universe, Shane L. Larson

Public Talks

No abstract provided.


Black Holes: Myths, Legends And Truths, Shane L. Larson Jun 2010

Black Holes: Myths, Legends And Truths, Shane L. Larson

Public Talks

No abstract provided.


Where In The World? Demographic Patterns In Access Data, Mimi Recker, Beijie Xu, Sherry Hsi, Christine Garrard Jun 2010

Where In The World? Demographic Patterns In Access Data, Mimi Recker, Beijie Xu, Sherry Hsi, Christine Garrard

Instructional Technology and Learning Sciences Faculty Publications

Standard webmetrics tools record the IP address of users’ computers, thereby providing fodder for analyses of their geographical location, and for understanding the impact of e-learning and teaching. Here we describe how two web-based educational systems were engineered to collect geo-referenced data. This is followed by a description of joining these data with demographic and educational datasets for the United States, and mapping different datasets using geographic information system (GIS) techniques to visually display their relationships. Results from statistical analyses of these relationships that highlight areas of significance are given.


El Niño-Southern Oscillation Effect On A Fire Regime In Northeastern Mexico Has Changed Over Time, Larissa L. Yocom Kent, Peter Z. Fule, Peter M. Brown, Julian Cerano, Jose Villanueva-Diaz, Donald A. Falk, Eladio Cornejo-Oviedo Jun 2010

El Niño-Southern Oscillation Effect On A Fire Regime In Northeastern Mexico Has Changed Over Time, Larissa L. Yocom Kent, Peter Z. Fule, Peter M. Brown, Julian Cerano, Jose Villanueva-Diaz, Donald A. Falk, Eladio Cornejo-Oviedo

Wildland Resources Faculty Publications

The El Niño Southern Oscillation (ENSO) is a climate-forcing mechanism that has been shown to affect precipitation and the occurrence of wildfires in many parts of the world. In the southern United States and northern Mexico, warm events (El Niño) are associated with moist winter conditions and fewer fires, while cool events (La Niña) tend to favor dry winters and more fires. We tested this relationship in a region of northeastern Mexico by characterizing the historical fire regime and climatic influences. Fire regimes were reconstructed from fire-scar samples collected from 100 trees in three high-elevation sites on Peña Nevada in …


Guide To Stakeholder Groups For Great Basin Sagebrush Steppe Restoration, Scott Hoffmann, Mark W. Brunson, Summer Olsen May 2010

Guide To Stakeholder Groups For Great Basin Sagebrush Steppe Restoration, Scott Hoffmann, Mark W. Brunson, Summer Olsen

Environment and Society Faculty Publications

As efforts are made to restore the health and functioning of sagebrush ecosystems within the Great Basin, various stakeholder interest groups have the potential to offer partnerships as well as adversarial involvement with land managers tasked with restoration. Given that greater than 60% of the Great Basin is publicly owned and managed by the Bureau of Land Management and other federal agencies, it is critical for those working in restoration to understand the views held by key stakeholder groups that may enhance or impair such efforts (Brunson and Peterson 2007). Gaining knowledge about and familiarity with those interest groups active …


Evaluation Of Constant Voltage Chamber Modifications, Justin Dekany Apr 2010

Evaluation Of Constant Voltage Chamber Modifications, Justin Dekany

Senior Theses and Projects

Determining the electrical properties of highly insulating materials can be a challenging task. These materials are designed to greatly resist the flow of electrical current making them useful in the construction of spacecraft. Due to the fact that satellites are isolated from ground, charging caused by the plasma environment found in typical orbital radii (1) is of concern to the designers of modern spacecraft (2). The Utah State University Materials Physics Group Constant Voltage Chamber (CVC) has been designed to measure extremely low currents and low conductivity. Over the last five years, many changes have been made to improve the …