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Full-Text Articles in Physical Sciences and Mathematics

Giants Among Micromorphs: Were Cincinnatian (Ordovician, Katian) Small Shelly Phosphatic Faunas Dwarfed?, Benjamin F. Dattilo, Rebecca L. Freeman, Winfried S. Peters, William P. Heimbrock, Bradley Deline, Anthony J. Martin, Jack W. Kallmeyer, Jesse Reeder, Anne Argast Feb 2016

Giants Among Micromorphs: Were Cincinnatian (Ordovician, Katian) Small Shelly Phosphatic Faunas Dwarfed?, Benjamin F. Dattilo, Rebecca L. Freeman, Winfried S. Peters, William P. Heimbrock, Bradley Deline, Anthony J. Martin, Jack W. Kallmeyer, Jesse Reeder, Anne Argast

Winfried S. Peters

Small fossils are preserved as phosphatic (carbonate fluorapatite) micro-steinkerns (∼ 0.5 mm diameter) in Upper Ordovician beds of the Cincinnati area. Mollusks are common, along with bryozoan zooecia, echinoderm ossicles, and other taxa. Similar occurrences of Ordovician micromorphic mollusks have been interpreted as ecologically dwarfed and adapted to oxygen-starved conditions, an interpretation with implications for ocean anoxia. An alternative explanation for small phosphatic steinkerns is taphonomic. Stable carbonate fluorapatite selectively filled small voids, thus preserving small fossils, including larval/young mollusks. Reworking concentrated small phosphatic steinkerns from multiple generations while larger, unfilled calcareous shells were destroyed, resulting in small fossils progressively …


Isotopic (Δ13c, Δ14c) Analysis Of Organic Acids In Marine Samples Using Wet Chemical Oxidation, Susan Lang, G. Früh-Green, S. Bernasconi, L. Wacker Jun 2015

Isotopic (Δ13c, Δ14c) Analysis Of Organic Acids In Marine Samples Using Wet Chemical Oxidation, Susan Lang, G. Früh-Green, S. Bernasconi, L. Wacker

Susan Q. Lang

We present a method for the isolation and off-line isotope analysis of formate and acetate in marine samples. Organic acids are separated by high performance liquid chromatography and collected in glass Exetainer® screw-capped vials that have been prespiked with an oxidant and flushed with helium. The vials are subsequently heated to convert the organic compounds to CO2 for radiocarbon and δ13C analysis. Small aliquots are sampled for measurement of δ13C by isotope ratio mass spectrometry, whereas the majority of the CO2 is saved for radiocarbon analysis by accelerator mass spectrometry using a gas ion source. Accurate δ13C and radiocarbon values …


The Weather And Air Traffic Management Integration Course In The Graduate Aeronautics Program At Embry-Riddle, John Lanicci Jun 2015

The Weather And Air Traffic Management Integration Course In The Graduate Aeronautics Program At Embry-Riddle, John Lanicci

John M Lanicci

One year ago, Embry-Riddle Aeronautical University added a new Area of Concentration (AOC) in Aviation Meteorology to the Master of Science in Aeronautics (MSA) program at the Daytona Beach, Florida campus. As part of the preparation for the start of this program, an experimental graduate seminar in Weather and Air Traffic Integration was taught over the summer, which attracted graduate students with backgrounds in commercial and private aviation, applied meteorology, and engineering physics. The purpose of this course was to introduce the students to the concept of weather and air traffic integration as it currently exists and is being planned …


Weather Technology In The Cockpit (Wtic): Concept Of Operations, User Needs, Education, And Training, John Lanicci, L. Kirk, L. Martin, J. Vacek, E. A. Roberts, M. Edwards Jun 2015

Weather Technology In The Cockpit (Wtic): Concept Of Operations, User Needs, Education, And Training, John Lanicci, L. Kirk, L. Martin, J. Vacek, E. A. Roberts, M. Edwards

John M Lanicci

The FAA, through sponsorship of the Center for General Aviation Research (CGAR), has funded a multi-disciplinary research program on Weather Technology In the Cockpit (WTIC). The CGAR is a consortium of four universities, three of which (Embry-Riddle Aeronautical University, University of North Dakota, University of Alaska-Anchorage) are working together on this program. Each university partner has the lead on a portion of the project: the University of Alaska-Anchorage is the lead on developing the WTIC Concept of Operations (CONOPS); the University of North Dakota is the lead on developing a robust set of WTIC user needs; Embry-Riddle Aeronautical University is …


General Aviation Weather Encounter Case Studies, John Lanicci, Massoud Bazargan, Daniel Halperin, Scott Shappell, Jaclyn Baron, Rebecca Iden, Carla Hackworth, Kali Holcomb Jun 2015

General Aviation Weather Encounter Case Studies, John Lanicci, Massoud Bazargan, Daniel Halperin, Scott Shappell, Jaclyn Baron, Rebecca Iden, Carla Hackworth, Kali Holcomb

John M Lanicci

This study presents a compilation of 24 cases involving general aviation (GA) pilots’ weather encounters over the continental U.S. The project team interviewed pilots who had experienced a weather encounter, and we examined their backgrounds, flight experience, and weather encounter details. Results from meteorological data analysis for each weather encounter were consistent with findings of larger GA weather accident studies in terms of the types of hazards encountered and flight phase during which the encounters occurred. Investigation of pilot weather products and the sources from which they were obtained revealed a lack of uniformity of pre-flight data sources and underutilization …


Analysis Of Climatological Rainfall Extremes Over The Kennedy Space Center Complex Using A High-Density Observational Network, John Lanicci, Adam Schnapp Jun 2015

Analysis Of Climatological Rainfall Extremes Over The Kennedy Space Center Complex Using A High-Density Observational Network, John Lanicci, Adam Schnapp

John M Lanicci

The use of observational datasets to determine the occurrence frequencies of extreme weather events has gained a lot of recent interest due to concerns about the potential regional impacts from global climate change. Extreme-value theory can quantify the return frequency of the most extreme events using climatologically short data sets and the assumption that such short climatological periods are stationary. However, the resulting analyses must be used with caution since they may not accurately reflect the potential of extreme events in the future due to climate change and variability. Accurately predicting extreme-event likelihood is important for building realistic long-range planning …


Assessing The Effectiveness Of An Education And Training Module For General Aviation Pilots On The Use Of Nexrad-Based Products In The Cockpit, John Lanicci, Erin Roberts, E. Blickensderfer Jun 2015

Assessing The Effectiveness Of An Education And Training Module For General Aviation Pilots On The Use Of Nexrad-Based Products In The Cockpit, John Lanicci, Erin Roberts, E. Blickensderfer

John M Lanicci

Numerous studies over the years have documented the need to improve meteorological education and training for General Aviation (GA) pilots. With the advent of readily available aviation weather hazard products for real-time pilot use on the flight deck, there is now a lack of education and training on the proper interpretation and usage of these products. Data-linked NEXRAD is a good example of a currently available real-time product that is very popular in the GA community, but lacks a coherent understanding of its proper usage in pre-flight planning and in-flight operation.

Proper usage of NEXRAD in the cockpit should require …


Guaranteed Access To Space, Kennedy Space Center/Cape Canaveral, And Climate Change, John Lanicci, J.E. Thropp Jun 2015

Guaranteed Access To Space, Kennedy Space Center/Cape Canaveral, And Climate Change, John Lanicci, J.E. Thropp

John M Lanicci

Guaranteed access to space is a major tenet of U.S. national security policy. Over the last 10 years, over two-thirds of U.S. space launches have originated from Cape Canaveral Air Force Station (CCAFS) and Kennedy Space Center (KSC), Florida. During the transition of the U.S. manned space program from a public-sector operation to a mixture of public and private sector responsibilities, continued access to space from the CCAFS/KSC complex is necessary to maintain U.S. leadership in space and the continuation of Space Situational Awareness, defined as understanding and maintaining awareness of the population of objects orbiting the earth. The CCAFS/KSC …


Weather And Collaborative Decision Making In The Aviation Community: Two “Tactical” Case Study Examples, John Lanicci, R. E. Haley, K. Rader Jun 2015

Weather And Collaborative Decision Making In The Aviation Community: Two “Tactical” Case Study Examples, John Lanicci, R. E. Haley, K. Rader

John M Lanicci

Collaborative Decision Making (CDM) in the aviation community has been defined as a “cooperative effort between the various components of aviation transportation, both government and industry, to exchange information for better decision making” (http://cdm.fly.faa.gov/). Two central tenets of CDM are that better information will lead to better decision-making, and that tools and procedures will enable air navigation service providers and flight operators to respond to changing conditions more readily. CDM can trace its roots to the mid 1990s, when airlines began sharing information about flight schedules with air traffic managers in an effort to determine potential “bottlenecks” in the National …


Satellite Measurements Of Mesospheric Gravity Wave Temperature Variance Over The Andes, Jonathan R. Pugmire, Michael J. Taylore, Yucheng Zhao May 2015

Satellite Measurements Of Mesospheric Gravity Wave Temperature Variance Over The Andes, Jonathan R. Pugmire, Michael J. Taylore, Yucheng Zhao

Jonathan Pugmire

Focusing on over 10 years of data from the SABER instrument aboard the TIMED satellite temperature variances are determined to quantify the signatures of short-period gravity waves propagating up into the mesosphere, and lower thermosphere (MLT) region. Temperature profile measurements were measured by SABER within a limited geographical area, centered on the Andes Lidar Observatory at Cerro Pachon, Chile (30.3° S, 70.7° S) where Utah State University has operated an OH Mesospheric Temperature Mapper (MTM) for the past 5 years. Using an established procedure the large-scale tidal waves, with wavenumbers 0-6, were removed from each profile revealing the gravity wave …


Observations Of Mesospheric Gravity Waves Over The Andes, Jonathan Pugmire Apr 2015

Observations Of Mesospheric Gravity Waves Over The Andes, Jonathan Pugmire

Jonathan Pugmire

Focusing on data from an imager and the SABER instrument aboard the TIMED satellite temperature variances are determined to quantify small-scale gravity waves. IDL software was used to extract all the temperature profile measurements that were measured by SABER within a limited geographical area, centered on our ground-based optical imager at Cerro Pachon, Chile (30.3°S, 70.7°S). Large-scale tidal waves, with wavenumbers 0-6, were removed from each profile revealing the gravity wave perturbations. Temperature variances reveal possible increased wave activity due to mountain waves. Mountain waves in the mesosphere are a relatively unexplored field in aeronomy. They are generated predominantly in …


Challenges Associated With Space Weather Analysis And Prediction, John Lanicci Apr 2015

Challenges Associated With Space Weather Analysis And Prediction, John Lanicci

John M Lanicci

The term “space weather” is typically used to describe environmental conditions in the region extending from the sun’s surface, through the interplanetary medium, to the earth’s magnetic field and upper atmosphere, with a focus on those conditions that can affect the earth, its technological systems, and population. Space weather conditions are monitored continuously by a number of agencies around the world. These agencies use both satellite- and ground-based measurements to build analyses and employ predictive models that form the basis for impacts-based products dealing with myriad users in satellite operations, the utility industry, aviation, and satellite-based communications, to name a …


Observations Of Mesospheric Gravity Wave Dynamics In The Southern Hemisphere, Jonathan Pugmire, Michael Taylor Oct 2014

Observations Of Mesospheric Gravity Wave Dynamics In The Southern Hemisphere, Jonathan Pugmire, Michael Taylor

Jonathan Pugmire

Observations of mesospheric OH rotational temperature by the Mesospheric Temperature Mapper located at Cerro Pachon, Chile (30.3°S, 70.7°S) show a large range of variation. Temperature variances reveal increased activity due to mountain waves. Comparative studies with the satellite carried SABER instrument show agreement on nightly, as well as seasonal, temperature measurements. Comparisons with similar temperature measurements from Maui, Hawaii (20.8°N) reveal mountain wave activity to be enhanced over the Andes in the winter months. Initial gravity wave measurements from McMurdo Base, Antarctica are highlighted.


Mesospheric Temperature Variability And Seasonal Characteristics Over The Andes, Jonathan Pugmire, Yucheng Zhao, Michael Taylor, P Pautet Oct 2014

Mesospheric Temperature Variability And Seasonal Characteristics Over The Andes, Jonathan Pugmire, Yucheng Zhao, Michael Taylor, P Pautet

Jonathan Pugmire

The Utah State University CEDAR Mesospheric Temperature Mapper (MTM) is a high-quality CCD imager capable of remote sensing faint optical emissions from the night sky to determine mesospheric temperature and its variability at an altitude of ~87 km. The MTM was operated at the new Andes Lidar Observatory (ALO)located at Cerro Pachon, Chile (30.2° S, 70.7° W) since August 2009 to investigate the seasonal characteristic of the mesopause at mid-latitudes. Measurement were made alongside a powerful lidar capable of height sounding the mesosphere. In this study, the MTM data have been analyzed to determine night to night variability and seasonal …


Effects Of Selective Grazing By Microzooplankton On Phytoplankton Composition In A Subtropical Estuary, Amanda Mcgehee Sep 2014

Effects Of Selective Grazing By Microzooplankton On Phytoplankton Composition In A Subtropical Estuary, Amanda Mcgehee

Amanda McGehee

Rates of phytoplankton growth and microzooplankton grazing were measured at two locations within the Bay of St. Louis, MS, over the course of three months to explore the dynamics of the phytoplankton community. Community growth rates were estimated based on the changes in chlorophyll a (chl a) concentration using the dilution technique, (Landry and Hassett, 1982) and a C-specific rate was obtained using chl a labeling (Redalje and Laws, 1981). Concentrations of chl a were determined using high performance liquid chromatography (HPLC) and fluorometry. HPLC was also employed to obtain class specific growth and grazing rates, using either marker pigments …


Sustainable Development, John Dernbach May 2014

Sustainable Development, John Dernbach

John C. Dernbach

No abstract provided.


Steady-State Aerosol Distributions In The Extra-Tropical, Lower Stratosphere And The Processes That Maintain Them, J. Wilson, Shan-Hu Lee, J. Reeves, C. Brock, H. Jonsson, B. Lafleur, M. Loewenstein, J. Podolske, E. Atlas, K. Boering, G. Toon, D. Fahey, T. Bui, G. Diskin, F. Moore Oct 2013

Steady-State Aerosol Distributions In The Extra-Tropical, Lower Stratosphere And The Processes That Maintain Them, J. Wilson, Shan-Hu Lee, J. Reeves, C. Brock, H. Jonsson, B. Lafleur, M. Loewenstein, J. Podolske, E. Atlas, K. Boering, G. Toon, D. Fahey, T. Bui, G. Diskin, F. Moore

Shan-Hu Lee

Measurements of aerosol, N2O and OCS made in the Northern Hemisphere below 21 km altitude following the eruption of Pinatubo are presented and analyzed. After September 1999, the oxidation of OCS and sedimentation of particles in the extra-tropical overworld north of 45 N are found to maintain the aerosol in a steady state. This analysis empirically links precursor gas to aerosol abundance throughout this region. These processes are tracked with age-of-air which offers advantages over tracking as a function of latitude and altitude. In the extra-tropical, lowermost stratosphere, normalized volume distributions appear constant in time after the fall of 1999. …


Ternary Homogeneous Nucleation Of H2so4, Nh3, And H2o Under Conditions Relevant To The Lower Troposphere, D. Benson, J. Yu, A. Markovich, Shan-Hu Lee Oct 2013

Ternary Homogeneous Nucleation Of H2so4, Nh3, And H2o Under Conditions Relevant To The Lower Troposphere, D. Benson, J. Yu, A. Markovich, Shan-Hu Lee

Shan-Hu Lee

Ternary homogeneous nucleation (THN) of H2SO4, NH3 and H2O has been used to explain new particle formation in various atmospheric regions, yet laboratory measurements of THN have failed to reproduce atmospheric observations. Here, we report first laboratory observations of THN made under conditions relevant to the lower troposphere ([H2SO4] of 106–107 cm−3, [NH3] of 0.08–20 ppbv, and a temperature of 288 K). Our observations show that NH3 can enhance atmospheric H2SO4aerosol nucleation and the enhancement factor (EF) in nucleation rate (J) due to NH3 (the ratio of Jmeasured with vs. without NH3) increases linearly with increasing [NH3] and increases with …


Uncertainty Associated With Modeling The Global Ionosphere, Janelle Jenniges, Ariel Acebal, Larry Gardner, Robert Schunk, Lie Zhu Sep 2013

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

Janelle V Jenniges

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 …


Eight Aggies Honored In 2013 Nsf Graduate Research Fellow Search, Michael Negale Jul 2013

Eight Aggies Honored In 2013 Nsf Graduate Research Fellow Search, Michael Negale

Michael Negale

No abstract provided.


Coastal Lagoons And Climate Change: Ecological And Social Ramifications In The U.S. Atlantic And Gulf Coast Ecosystems, Abigail Anthony, Joshua Atwood, Peter August, Carrie Byron, Stanley Cobb, Cheryl Foster, Crystal Fry, Arthur Gold, Kifle Hagos, Leanna Heffner, D. Kellogg, Kimberly Lellis-Dibble, James Opaluch, Candace Oviatt, Anna Pfeiffer-Herbert, Nicole Rohr, Leslie Smith, Tiffany Smythe, Judith Swift, Nathan Vinhateiro May 2013

Coastal Lagoons And Climate Change: Ecological And Social Ramifications In The U.S. Atlantic And Gulf Coast Ecosystems, Abigail Anthony, Joshua Atwood, Peter August, Carrie Byron, Stanley Cobb, Cheryl Foster, Crystal Fry, Arthur Gold, Kifle Hagos, Leanna Heffner, D. Kellogg, Kimberly Lellis-Dibble, James Opaluch, Candace Oviatt, Anna Pfeiffer-Herbert, Nicole Rohr, Leslie Smith, Tiffany Smythe, Judith Swift, Nathan Vinhateiro

Peter August

Lagoons are highly productive coastal features that provide a range of natural services that society values. Their setting within the coastal landscape leaves them especially vulnerable to profound physical, ecological, and associated societal disturbance from global climate change. Expected shifts in physical and ecological characteristics range from changes in flushing regime, freshwater inputs, and water chemistry to complete inundation and loss and the concomitant loss of natural and human communities. Therefore, managing coastal lagoons in the context of global climate change is critical. Although management approaches will vary depending on local conditions and cultural norms, all management scenarios will need …


The Sustainable Relationship: What The United States And The United Kingdom Can Teach Each Other About Climate Change And Sustainable Development At The National Level, John Dernbach, Andrea Ross Apr 2013

The Sustainable Relationship: What The United States And The United Kingdom Can Teach Each Other About Climate Change And Sustainable Development At The National Level, John Dernbach, Andrea Ross

John C. Dernbach

No abstract provided.


Meteoric 10Be, FeD, And Clay In Critical Zone Soils, Front Range, Colorado, Cianna Wyshnytzky, James Mccarthy Mar 2013

Meteoric 10Be, FeD, And Clay In Critical Zone Soils, Front Range, Colorado, Cianna Wyshnytzky, James Mccarthy

Cianna E Wyshnytzky

The critical zone is the zone within which meteoric water, atmospheric gases, soil, and bedrock interact, encompassing the zone of soil formation (Anderson et al., 2007). The concentrations of various pedogenic compounds at a given location indicate the degree of weathering that has taken place in the Critical Zone. Among the products of chemical weathering are secondary phyllosilicate minerals (clays) and iron (Birkeland, 1999). At stable sites, chronosequence studies have shown that the amount of pedogenic iron oxide and clay increase as soils become older (McFadden and Hendricks, 1985).

Meteoric ¹⁰Be is a cosmogenic nuclide produced from oxygen and nitrogen …


Holocene Sediment Distribution On The Inner Continental Shelf Of Northeastern South Carolina: Implications For The Regional Sediment Budget And Long-Term Shoreline Response, Jenny Denny, William Schwab, Wayne Baldwain, Walter Barnhadt, Paul Gayes, Robert Morton, John Warner, Neil Driscoll, George Voulgaris Mar 2013

Holocene Sediment Distribution On The Inner Continental Shelf Of Northeastern South Carolina: Implications For The Regional Sediment Budget And Long-Term Shoreline Response, Jenny Denny, William Schwab, Wayne Baldwain, Walter Barnhadt, Paul Gayes, Robert Morton, John Warner, Neil Driscoll, George Voulgaris

George Voulgaris

High-resolution geophysical and sediment sampling surveys were conducted offshore of the Grand Strand, South Carolina to define the shallow geologic framework of the inner shelf. Results are used to identify and map Holocene sediment deposits, infer sediment transport pathways, and discuss implications for the regional coastal sediment budget.

The thickest deposits of Holocene sediment observed on the inner shelf form shoal complexes composed of moderately sorted fine sand, which are primarily located offshore of modern tidal inlets. These shoal deposits contain ∼67 M m3 of sediment, approximately 96% of Holocene sediment stored on the inner shelf. Due to the lack …


Usu Grad Student, Researchers Collect Project Data At South Pole, Kevin Opsahl Mar 2013

Usu Grad Student, Researchers Collect Project Data At South Pole, Kevin Opsahl

Jonathan Pugmire

No abstract provided.


Usu Grad Student Travels To South Pole, Kylie Conway Mar 2013

Usu Grad Student Travels To South Pole, Kylie Conway

Jonathan Pugmire

No abstract provided.


Usu Team Travels To South Pole To Measure Gravity Waves, Nancy Van Valkenburg Mar 2013

Usu Team Travels To South Pole To Measure Gravity Waves, Nancy Van Valkenburg

Jonathan Pugmire

No abstract provided.


Development Of A New Lagrangian Float For Studying Coastal Marine Ecosystems, Alex Schwithal, Chris Roman Jan 2013

Development Of A New Lagrangian Float For Studying Coastal Marine Ecosystems, Alex Schwithal, Chris Roman

Christopher N. Roman

This paper presents an overview and initial testing results for a shallow water Lagrangian float designed to operate in coastal settings. The presented effort addresses the two main characteristics of the shallow coastal environment that preclude the direct of use of many successfully deep water floats, namely the higher variation of water densities near the coast compared with the open ocean and the highly varied bathymetry. Our idea is to develop a high capacity dynamic auto-ballasting system that is able to compensate for the expected seawater density variation over a broad range of water temperatures and salinities while using measurements …


Submarine Volcanism In The Straits Of Sicily, Steven Carey, Katherine Bell, Michael Marani, Mauro Rosi, Edward Baker, Chris Roman, Marco Pistolesi, Joshua Kelly Jan 2013

Submarine Volcanism In The Straits Of Sicily, Steven Carey, Katherine Bell, Michael Marani, Mauro Rosi, Edward Baker, Chris Roman, Marco Pistolesi, Joshua Kelly

Christopher N. Roman

No abstract provided.


The Development Of High-Resolution Seafloor Mapping Techniques, Chris Roman, Gabrielle Inglis, J. Vaughn, Clara Smart, Bertrand Douillard, Stefan Williams Jan 2013

The Development Of High-Resolution Seafloor Mapping Techniques, Chris Roman, Gabrielle Inglis, J. Vaughn, Clara Smart, Bertrand Douillard, Stefan Williams

Christopher N. Roman

No abstract provided.