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Oceanography and Atmospheric Sciences and Meteorology

2015

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Articles 1 - 30 of 723

Full-Text Articles in Physical Sciences and Mathematics

Losing Ground, Alison Kanski Dec 2015

Losing Ground, Alison Kanski

Capstones

Climate change and sea level rise are slowly decimating beaches. But the U.S. government and loyal residents won't let go of the beaches so easily.

A determined resident of the Rockaways in New York fights for the money and attention from governments to sustain his lifelong home and stop it from washing away.


Operational Exploitation Of Satellite-Based Sounding Data And Numerical Weather Prediction Models For Directed Energy Applications, David C. Meier Dec 2015

Operational Exploitation Of Satellite-Based Sounding Data And Numerical Weather Prediction Models For Directed Energy Applications, David C. Meier

Theses and Dissertations

The wealth of available scientific data collected by the modern constellation of meteorological satellites can be exploited in new and innovative ways, with direct benefit to directed energy applications. The Atmospheric Infrared Sounder (AIRS) provides accurate, geolocated temperature data, which are used as the starting point for the derivation of atmospheric parameters critical to prediction of sensor or directed energy system performance. Twenty-four hour data coverage is achieved by extending the atmospheric characterization between satellite observations using Numerical Weather Prediction (NWP) models. A technique is developed to derive wind profiles using AIRS temperature data and the accuracy of these winds …


Comparison Of Coincident Rayleigh-Scatter And Sodium Resonance Lidar Temperature Measurements From The Mesosphere-Lower-Thermosphere Region, Leda Sox, Vincent B. Wickwar, Neal R. Criddle, Tao Yuan Dec 2015

Comparison Of Coincident Rayleigh-Scatter And Sodium Resonance Lidar Temperature Measurements From The Mesosphere-Lower-Thermosphere Region, Leda Sox, Vincent B. Wickwar, Neal R. Criddle, Tao Yuan

All Physics Faculty Publications

There are relatively few instruments that have the capabilities to make near continuous measurements of the mesosphere-lower-thermosphere (MLT) region. Rayleigh scatter and resonance lidars, particularly sodium resonance lidar, have been the two dominant ground-based techniques for acquiring mesosphere and MLT vertical temperature profiles, respectively, for more than two decades. With these measurements, the dynamics (gravity waves, tides) and long-term temperature trends (upper atmosphere cooling) of the MLT region can be studied. The Utah State University (USU; 41.7º N, 111.8º W) campus hosts a unique upper atmospheric observatory which houses both a high-power, large-aperture Rayleigh lidar and a sodium resonance Doppler …


Comparison Of Coincident Rayleigh-Scatter And Sodium Resonance Lidar Temperature Measurements From The Mesosphere-Lower-Thermosphere Region, Leda Sox, Vincent B. Wickwar, Neal R. Criddle, Tao Yuan Dec 2015

Comparison Of Coincident Rayleigh-Scatter And Sodium Resonance Lidar Temperature Measurements From The Mesosphere-Lower-Thermosphere Region, Leda Sox, Vincent B. Wickwar, Neal R. Criddle, Tao Yuan

All Physics Faculty Presentations

There are relatively few instruments that have the capabilities to make near continuous measurements of the mesosphere-lower-thermosphere (MLT) region. Rayleigh scatter and resonance lidars, particularly sodium resonance lidar, have been the two dominant ground-based techniques for acquiring mesosphere and MLT vertical temperature profiles, respectively, for more than two decades. With these measurements, the dynamics (gravity waves, tides) and long-term temperature trends (upper atmosphere cooling) of the MLT region can be studied. The Utah State University (USU; 41.7º N, 111.8º W) campus hosts a unique upper atmospheric observatory which houses both a high-power, large-aperture Rayleigh lidar and a sodium resonance Doppler …


Dynamics Of Density Cavities Generated By Frictional Heating: Formation, Distortion, And Instability, M. D. Zettergren, J. L. Semeter, H. Dahlgren Dec 2015

Dynamics Of Density Cavities Generated By Frictional Heating: Formation, Distortion, And Instability, M. D. Zettergren, J. L. Semeter, H. Dahlgren

Publications

A simulation study of the generation and evolution of mesoscale density cavities in the polar ionosphere is conducted using a time-dependent, nonlinear, quasi-electrostatic model. The model demonstrates that density cavities, generated by frictional heating, can form in as little as 90 s due to strong electric fields of ∼120 mV/m, which are sometimes observed near auroral zone and polar cap arcs. Asymmetric density cavity features and strong plasma density gradients perpendicular to the geomagnetic field are naturally generated as a consequence of the strong convection and finite extent of the auroral feature. The walls of the auroral density cavities are …


Odu, William & Mary Seek Funds For Joint Center On Sea-Level Rise, Dave Mayfield Dec 2015

Odu, William & Mary Seek Funds For Joint Center On Sea-Level Rise, Dave Mayfield

News Items

No abstract provided.


Propagation Of Tsunami-Driven Gravity Waves Into The Thermosphere And Ionosphere, Michael P. Hickey, G. Schubert, R. L. Walterscheid Dec 2015

Propagation Of Tsunami-Driven Gravity Waves Into The Thermosphere And Ionosphere, Michael P. Hickey, G. Schubert, R. L. Walterscheid

Michael P. Hickey

Recent observations have revealed large F-region electron density perturbations (~100%) and total electron content (TEC) perturbations (~30%) that appear to be correlated with tsunamis. The characteristic speed and horizontal wavelength of the disturbances are ~200 m/s and ~400 km. We describe numerical simulations using our spectral full-wave model (SFWM) of the upward propagation of a spectrum of gravity waves forced by a tsunami, and the interaction of these waves with the F-region ionosphere. The SFWM describes the propagation of linear, steady-state acoustic-gravity waves in a nonisothermal atmosphere with the inclusion of eddy and molecular diffusion of heat and momentum, ion …


Propagation Of Tsunami-Driven Gravity Waves Into The Thermosphere And Ionosphere, Michael P. Hickey, G. Schubert, R. L. Walterscheid Dec 2015

Propagation Of Tsunami-Driven Gravity Waves Into The Thermosphere And Ionosphere, Michael P. Hickey, G. Schubert, R. L. Walterscheid

Michael P. Hickey

Recent observations have revealed large F-region electron density perturbations (~100%) and total electron content (TEC) perturbations (~30%) that appear to be correlated with tsunamis. The characteristic speed and horizontal wavelength of the disturbances are ~200 m/s and ~400 km. We describe numerical simulations using our spectral full-wave model (SFWM) of the upward propagation of a spectrum of gravity waves forced by a tsunami, and the interaction of these waves with the F-region ionosphere. The SFWM describes the propagation of linear, steady-state acoustic-gravity waves in a nonisothermal atmosphere with the inclusion of eddy and molecular diffusion of heat and momentum, ion …


Can The Financialised Atmosphere Be Effectively Regulated And Accounted For?, Patty Mcnicholas, Carolyn Windsor Dec 2015

Can The Financialised Atmosphere Be Effectively Regulated And Accounted For?, Patty Mcnicholas, Carolyn Windsor

Carolyn Windsor

Purpose – This paper aims to carry out a critical analysis of the proposed Australian emissions trading scheme (ETS) as a complex market solution to reduce greenhouse gases (GHGs). Specifically it seeks to examine the financial regulatory infrastructure that will more than likely oversee the Australian ETS, the same regulatory infrastructure which failed to prevent the global financial crisis.Design/methodology/approach – A critical examination of the financialisation of the atmosphere that follows the growth of the financialisation of capitalism when economic activity shifted from production and service sectors to finance. Financialisation of capitalism is supported by capitalist regulation influenced by neo-liberal …


Revisiting 3d Stereo Satellite Image Displays, Frederick R. Mosher Dec 2015

Revisiting 3d Stereo Satellite Image Displays, Frederick R. Mosher

Frederick R. Mosher

Over 30 years ago, there were a number of development efforts to display 3D stereo satellite images and associated weather. Dr. Fritz Hasler showed how the GOES-east and west satellites could be remapped to generate true stereo pairs for obtaining cloud heights and he also showed how artificial stereo images could be generated using derived IR cloud heights to generate parallax shifts for the visible or infrared images. While there was a flurry of interest in the 1980s, the techniques had largely fallen from routine usage until recently. However, technology advances in both satellites and display technology has allowed for …


Revisiting 3d Stereo Satellite Image Displays, Frederick R. Mosher Dec 2015

Revisiting 3d Stereo Satellite Image Displays, Frederick R. Mosher

Frederick R. Mosher

Over 30 years ago, there were a number of development efforts to display 3D stereo satellite images and associated weather. Dr. Fritz Hasler showed how the GOES-east and west satellites could be remapped to generate true stereo pairs for obtaining cloud heights and he also showed how artificial stereo images could be generated using derived IR cloud heights to generate parallax shifts for the visible or infrared images. While there was a flurry of interest in the 1980s, the techniques had largely fallen from routine usage until recently. However, technology advances in both satellites and display technology has allowed for …


Revisiting 3d Stereo Satellite Image Displays, Frederick R. Mosher Dec 2015

Revisiting 3d Stereo Satellite Image Displays, Frederick R. Mosher

Frederick R. Mosher

Over 30 years ago, there were a number of development efforts to display 3D stereo satellite images and associated weather. Dr. Fritz Hasler showed how the GOES-east and west satellites could be remapped to generate true stereo pairs for obtaining cloud heights and he also showed how artificial stereo images could be generated using derived IR cloud heights to generate parallax shifts for the visible or infrared images. While there was a flurry of interest in the 1980s, the techniques had largely fallen from routine usage until recently. However, technology advances in both satellites and display technology has allowed for …


Natural Vs. Anthropogenic Sedimentation: Does Reducing A Local Stressor Increase Coral Resilience To Climate Change?, Francesca Fourney Dec 2015

Natural Vs. Anthropogenic Sedimentation: Does Reducing A Local Stressor Increase Coral Resilience To Climate Change?, Francesca Fourney

HCNSO Student Theses and Dissertations

Corals face serious worldwide population declines due to global climate change in combination with direct anthropogenic impacts. Global climate change is difficult to manage locally, but policy makers can regulate the magnitude of local stressors affecting reefs. The objective of this experiment is to investigate if reducing sedimentation will enable reef corals to better endure global climate change. It has been shown that some coral species can handle climate change stress when provided with additional energy resources. Here I tested if the capacity of corals to cope with climate change can be improved when their ability to feed and photosynthesize …


The Our Florida Reefs Coastal Use Survey: An Online Survey To Support Stakeholder Management Recommendations For Southeast Florida, Amanda Rose Costaregni Dec 2015

The Our Florida Reefs Coastal Use Survey: An Online Survey To Support Stakeholder Management Recommendations For Southeast Florida, Amanda Rose Costaregni

HCNSO Student Theses and Dissertations

Coral reefs are an important resource world-wide. Unfortunately, coral reef conditions are declining in many areas due to both global and local stressors. The objective of this study was to survey stakeholders in southeast Florida to better understand reef use in the region. Stakeholders spatially identified where and how often they conducted their activities. These data were compiled and analyzed in GIS to determine spatial use patterns. Both location and intensity of use were analyzed to determine which areas may be under greater stress from recreational activities. It was found that reef use was not evenly distributed in the region …


Three-Dimensional Wind Speed And Flux Measurements Over A Rain-Fed Soybean Field Using Orthogonal And Non-Orthogonal Sonic Anemometer Designs, Taylor Thomas Dec 2015

Three-Dimensional Wind Speed And Flux Measurements Over A Rain-Fed Soybean Field Using Orthogonal And Non-Orthogonal Sonic Anemometer Designs, Taylor Thomas

School of Natural Resources: Dissertations, Theses, and Student Research

The eddy covariance method for estimating fluxes of trace gases, energy and momentum in the constant flux layer above a plant canopy fundamentally relies on accurate measurements of the vertical wind speed. This wind speed is typically measured using a three-dimensional ultrasonic anemometer. Previous studies comparing anemometers with orthogonal transducer sets to those with non-orthogonal transducer sets suggest differences in measured 3D wind speed components, particularly for a vertical component. These differences, attributed to additional flow distortion caused by the non-orthogonal transducer arrangement and support structure, directly affect fluxes of trace gases, energy and momentum. A field experiment was conducted …


A Comparison Of Infaunal Community Structure Between Pre- And Post Construction Sampling Of Artificial Fdot Rock- Pile Reefs In Broward County, Florida, Joan Lorraine Guerra Dec 2015

A Comparison Of Infaunal Community Structure Between Pre- And Post Construction Sampling Of Artificial Fdot Rock- Pile Reefs In Broward County, Florida, Joan Lorraine Guerra

HCNSO Student Theses and Dissertations

Artificial reefs (ARs) are generally created with the intention of increasing local fish populations, biodiversity and corresponding habitat productivity, most often in support of commercial and recreational uses (e.g., diving and fishing). Numerous studies have investigated the communities that develop on artificial reefs. By contrast, far less research has focused on the surrounding infaunal communities, which represent critical trophic resources for many species that populate both natural and artificial reefs, and which may be affected both by AR deployment and the organisms that subsequently recruit to them. This study compared infaunal organism abundances at four sites between the inner and …


Development And Evaluation Of A Multi-Year Fractional Surface Water Data Set Derived From Active/Passive Microwave Remote Sensing Data, Ronny Schroeder, Kyle C. Mcdonald, Bruce D. Chapman, Katherine Jensen, Erika Podest, Zachary D. Tessler, Theodore J. Bohn, Reiner Zimmermann Dec 2015

Development And Evaluation Of A Multi-Year Fractional Surface Water Data Set Derived From Active/Passive Microwave Remote Sensing Data, Ronny Schroeder, Kyle C. Mcdonald, Bruce D. Chapman, Katherine Jensen, Erika Podest, Zachary D. Tessler, Theodore J. Bohn, Reiner Zimmermann

Publications and Research

The sensitivity of Earth’s wetlands to observed shifts in global precipitation and temperature patterns and their ability to produce large quantities of methane gas are key global change questions. We present a microwave satellite-based approach for mapping fractional surface water (FW) globally at 25-km resolution. The approach employs a land cover-supported, atmospherically-corrected dynamic mixture model applied to 20+ years (1992–2013) of combined, daily, passive/active microwave remote sensing data. The resulting product, known as Surface WAter Microwave Product Series (SWAMPS), shows strong microwave sensitivity to sub-grid scale open water and inundated wetlands comprising open plant canopies. SWAMPS’ FW compares favorably (R2 …


Connectivity Of Coastal And Oceanic Ecosystems: Pelagic Habitat Use By Juvenile Reef Fishes In The Gulf Of Mexico, Katie Bowen Dec 2015

Connectivity Of Coastal And Oceanic Ecosystems: Pelagic Habitat Use By Juvenile Reef Fishes In The Gulf Of Mexico, Katie Bowen

HCNSO Student Theses and Dissertations

The assemblage structure, abundance, biomass, and vertical distribution of juvenile reef fishes in the offshore pelagic habitat of the northern Gulf of Mexico are described as part of the NOAA-supported Offshore Nekton Sampling and Analysis Program. The results presented here are from a 3-month, continuous sampling series in 2011 in which discrete depth strata from 0 to 1500 m were sampled using a 10-m2 MOCNESS midwater trawl. This is the first study to examine pelagic juvenile reef fish distributions across the entire oceanic northern Gulf of Mexico seaward of the continental shelf break after the Deepwater Horizon Oil Spill. …


Faunal Composition And Distribution Of Pelagic Larval And Juvenile Flatfishes (Teleostei: Pleuronectiformes) In The Northern Gulf Of Mexico: Connectivity Between Coastal And Oceanic Epipelagic Ecosystems, Lacey Malarky Dec 2015

Faunal Composition And Distribution Of Pelagic Larval And Juvenile Flatfishes (Teleostei: Pleuronectiformes) In The Northern Gulf Of Mexico: Connectivity Between Coastal And Oceanic Epipelagic Ecosystems, Lacey Malarky

HCNSO Student Theses and Dissertations

Pleuronectiformes (flatfishes) occur throughout the global oceans, and have high ecological and commercial importance in some areas. Though much is known regarding life history, abundance, and distribution for the benthic adult stage of flatfish species, much less is known about the pelagic larval phases of flatfishes in the open ocean. Taxonomic uncertainty and limited sampling in the oceanic Gulf of Mexico contribute to data gaps with respect to the distribution of early life history stage of flatfishes in this region. Knowledge of the faunal composition, abundance and distribution of larval flatfishes, such as members of Bothus, which have extended …


Feeding Ecology Of The Invasive Lionfish (Pterois Spp.) And Comparison With Two Native Species: Schoolmaster Lutjanus Apodus (Walbaum, 1792) And Graysby Cephalopholis Cruentata (Lacepède, 1802), Jesse J. Secord Dec 2015

Feeding Ecology Of The Invasive Lionfish (Pterois Spp.) And Comparison With Two Native Species: Schoolmaster Lutjanus Apodus (Walbaum, 1792) And Graysby Cephalopholis Cruentata (Lacepède, 1802), Jesse J. Secord

HCNSO Student Theses and Dissertations

Predator satiation and prey-size preference were determined for locally caught lionfish, schoolmaster, and graysby, all co-occurring predatory fishes in the Florida coral reef ecosystem. Individuals were evaluated by exposing them to wild-caught killifish over a gradient of four size classes (20 mm to 60 mm, in 10 mm increments). Preference trials extended over a 2 hr time period and were filmed to determine the order in which each prey item was consumed. Satiation was evaluated by exposing the predators to an equal number of excess prey items for 24 hrs and evaluating consumed prey weight. Lionfish and schoolmaster showed a …


No Reef Is An Island: Integrating Coral Reef Connectivity Data Into The Design Of Regional-Scale Marine Protected Area Networks, Steven R. Schill, George T. Raber, Jason J. Roberts, Eric A. Treml, Jorge Brenner, Patrick N. Halpin Dec 2015

No Reef Is An Island: Integrating Coral Reef Connectivity Data Into The Design Of Regional-Scale Marine Protected Area Networks, Steven R. Schill, George T. Raber, Jason J. Roberts, Eric A. Treml, Jorge Brenner, Patrick N. Halpin

Faculty Publications

We integrated coral reef connectivity data for the Caribbean and Gulf of Mexico into a conservation decision-making framework for designing a regional scale marine protected area (MPA) network that provides insight into ecological and political contexts. We used an ocean circulation model and regional coral reef data to simulate eight spawning events from 2008–2011, applying a maximum 30-day pelagic larval duration and 20% mortality rate. Coral larval dispersal patterns were analyzed between coral reefs across jurisdictional marine zones to identify spatial relationships between larval sources and destinations within countries and territories across the region. We applied our results in Marxan, …


The Effects Of Petroleum Pollutants On Sea Urchins Reproduction And Development, Kellie C. Pelikan Dec 2015

The Effects Of Petroleum Pollutants On Sea Urchins Reproduction And Development, Kellie C. Pelikan

HCNSO Student Theses and Dissertations

Disturbances, such as mass pollution events, threaten the health of vulnerable ecosystems. Recent media attention has focused on the devastating mass oil spills, but daily petroleum input from recreational and commercial ship bilge release has been overlooked. The focus of this study was the effect of petroleum products found in bilge water on fertilization success and larval viability of two sea urchin species, Lytechinus variegatus and Eucidaris tribuloides. Unlike other pollutant studies that have focused on sperm characteristics and concentrations, I chose to examine how egg integrity was compromised by petroleum products. Scanning electron microscopy revealed eggs were degraded when …


A New Technique For Interpreting Depolarization Measurements Using The Crl Atmospheric Lidar In The Canadian High Arctic, Emily M. Mccullough Dec 2015

A New Technique For Interpreting Depolarization Measurements Using The Crl Atmospheric Lidar In The Canadian High Arctic, Emily M. Mccullough

Electronic Thesis and Dissertation Repository

Linear depolarization measurement capabilities were added to the CANDAC Rayleigh-Mie-Raman lidar (CRL) at Eureka, Nunavut, in the Canadian High Arctic. This upgrade enables inferences of the phases (liquid versus ice) of cold and mixed-phase clouds, including during polar winter. A rotating-polarizer module was installed in the lidar, and depolarization measurements were calibrated according to existing methods. An alternate calculation technique, using the lidar's existing visible Rayleigh elastic channel in combination with the new rotating polarizer channel, was developed. A detailed mathematical description of both methods and their calibrations is presented. The new method is superior to the traditional method for …


Rear-Flank Outflow Dynamics And Thermodynamics In The 10 June 2010 Last Chance, Colorado Supercell, Curtis J. Riganti Dec 2015

Rear-Flank Outflow Dynamics And Thermodynamics In The 10 June 2010 Last Chance, Colorado Supercell, Curtis J. Riganti

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

On 10 June 2010, the second Verification of the Origins of Tornadoes Experiment (VORTEX2) armada observed the non-tornadic phase of a supercell thunderstorm near Last Chance, Colorado. Tempest unmanned aircraft system (UAS) data collected in the rear-flank outflow revealed what appeared to be an elevated outflow head, turbulent wake, and a cold secondary outflow surge. Surface thermodynamic and kinematic data collected by StickNets and mobile mesonets suggested that the outflow wake may have extended to or very near the surface, perhaps cutting off the leading edge of the outflow at times. Single-Doppler data collected by the NOAA X-Pol Mobile Polarimetric …


Iodine-131: Measurement And Application Of A Novel Tracer In Lake Michigan, Michael Patrick Montenero Dec 2015

Iodine-131: Measurement And Application Of A Novel Tracer In Lake Michigan, Michael Patrick Montenero

Theses and Dissertations

Iodine-131 is a short-lived (half-life=8.0233 days), gamma emitting, radiopharmaceutical that, when excreted by patients, enters aquatic systems via sewage effluent discharged from water reclamation facilities (WRFs). Here, I report on 131I activities in the nearshore of southwest Lake Michigan in the vicinity of Milwaukee, Wisconsin. This is the first report on 131I activity in any of the Great Lakes of North America.

The flux of 131I from Milwaukee’s two WRFs was monitored from July 2013 to December 2014. Mean discharge of 131I from the Jones Island WRF was (0.664 ± 0.012)×108 Bq d-1 (mean effluent 131I activity: ~0.25 Bq L-1; …


The Visual Framing Of The Three Cycles Of Climate Control In The New York Times 1851 To Present, Jason Lee Thompson Dec 2015

The Visual Framing Of The Three Cycles Of Climate Control In The New York Times 1851 To Present, Jason Lee Thompson

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research explored the visual framing of climate control in The New York Times through three cycles of media history. Although no peer-reviewed study has explored this specific topic, a wealth of prior communication articles on both the visual and textual aspects of climate change and geoengineering in the media was mined in order to discover the frames present. Once the visual frames of climate control (war, fix, people, and impacts) were revealed a content analysis was conducted in order to see which frame elements were most and least frequent considering the images of climate control. When combining all three …


Economic Feasibility Of Aquaponics In Arkansas, Leah Ashley English Dec 2015

Economic Feasibility Of Aquaponics In Arkansas, Leah Ashley English

Graduate Theses and Dissertations

Concerns regarding population growth and resource scarcity have led to a recent renaissance of food production research. Over the past few decades, scientists have discovered new and innovative methods for growing food that, cumulatively, may hold the key to efficiently and sustainably feeding an ever-increasing world population. One method, known as aquaponics, has shown promise as being a sustainable solution for producing food locally in all parts of the world. Although many studies have shown aquaponic food production to be technically feasible, there are relatively few studies concerning the economic feasibility of aquaponics in various regions. To determine whether aquaponics …


Habitat Utilization And Vertical Distribution Of The Great Barracuda Sphyraena Barracuda (Edwards 1771) In The Western North Atlantic Using Electronic Archival Tags, Noah R. Hansen, David W. Kerstetter Dec 2015

Habitat Utilization And Vertical Distribution Of The Great Barracuda Sphyraena Barracuda (Edwards 1771) In The Western North Atlantic Using Electronic Archival Tags, Noah R. Hansen, David W. Kerstetter

Marine & Environmental Sciences Faculty Articles

The Great Barracuda Sphyraena barracuda is a large predatory teleost commonly seen in the tropics of the Western North Atlantic. Using pop-up satellite archival tags (PSATs), two large Great Barracuda (101 and 104 cm FL) were tagged off South Florida for a 15-day deployment period. Great Barracuda 88094 traveled 471 km minimum straight-line distance (MSLD) over the deployment duration, while Great Barracuda 88095 traveled 1231 km MSLD. Great barracuda 88094 achieved a maximum depth of 145.2 m, while 88095 to a maximum depth of 186.9 m, although such movements were for short time durations. The data obtained indicate significant differences …


Modifying A Cow-Calf Biophysical Simulation Model For Analyses Of Alternative Enterprises, Jennifer L. Lutes Dec 2015

Modifying A Cow-Calf Biophysical Simulation Model For Analyses Of Alternative Enterprises, Jennifer L. Lutes

Graduate Theses and Dissertations

Cow-calf producers in the United States, tasked with providing beef calves for the beef industry, have had a multitude of difficulties to overcome in recent years. Producers in northwest Arkansas were negatively impacted by high hay prices coupled with low beef cattle market prices due to severe drought experienced in portions of 2010, 2011, and 2012. During this time they also faced high grain prices, due to a record low harvest, combined with portions of the corn harvest diverted from human and animal feed to ethanol production. Tight lending policies of this time, reminiscent of the housing market crash in …


Semi-Automated Object-Based Classification Of Coral Reef Habitat Using Discrete Choice Models, Steven Saul, Samuel J. Purkis Dec 2015

Semi-Automated Object-Based Classification Of Coral Reef Habitat Using Discrete Choice Models, Steven Saul, Samuel J. Purkis

Marine & Environmental Sciences Faculty Articles

As for terrestrial remote sensing, pixel-based classifiers have traditionally been used to map coral reef habitats. For pixel-based classifiers, habitat assignment is based on the spectral or textural properties of each individual pixel in the scene. More recently, however, object-based classifications, those based on information from a set of contiguous pixels with similar properties, have found favor with the reef mapping community and are starting to be extensively deployed. Object-based classifiers have an advantage over pixel-based in that they are less compromised by the inevitable inhomogeneity in per-pixel spectral response caused, primarily, by variations in water depth. One aspect of …