Oceanography and Atmospheric Sciences and Meteorology Commons^™

Efficacy Of The Localized Aviation Mos Program In Ceiling Flight Category Forecasts, Douglas D. Boyd, Thomas A. Guinn

Publications

(1) Background: Flying in instrument meteorological conditions (IMC) carries an elevated risk of fatal outcome for general aviation (GA) pilots. For the typical GA flight, aerodrome-specific forecasts (Terminal Aerodrome Forecast (TAF), Localized Aviation Model Output Statistics Program (LAMP)) assist the airman in pre-determining whether a flight can be safely undertaken. While LAMP forecasts are more prevalent at GA-frequented aerodromes, the Federal Aviation Administration (FAA) recommends that this tool be used as supplementary to the TAF only. Herein, the predictive accuracy of LAMP for ceiling flight categories of visual flight rules (VFR) and instrument flight rules (IFR) was determined. (2) Methods: …

Combined Report: Aviation Weather Knowledge Assessment & General Aviation (Ga) Pilots’ Interpretation Of Weather Products, Beth Blickensderfer, John Lanicci, Thomas A. Guinn, Robert Thomas, Jennifer E. Thropp, Jayde King, Yolanda Ortiz, Jessica Cruit, Nicholas Defilippis, Krijn Berendschot, Jacqueline Mcsorley, John Kleber

General Aviation Weather Display Interpretation

Prior research has indicated that general aviation (GA) pilots may lack adequate knowledge of aviation weather concepts and skill at interpreting aviation weather displays. Therefore, the purpose of the current project was to develop and validate a comprehensive set of aviation weather knowledge and interpretation multiple-choice questions, and in turn, to use the questions to assess pilot understanding of aviation weather concepts and displays. An interdisciplinary research team that included two meteorologists, one Gold Seal Certificated Flight Instructor (CFI), a human factors psychologist, and several human factors graduate students performed this research.

Application Of A Hybrid Statistical–Dynamical System To Seasonal Prediction Of North American Temperature And Precipitation, Sarah Strazzo, Dan C. Collins, Andrew Schepen, Q. J. Wang, Emily Becker, Liweli Jia

Publications

Recent research demonstrates that dynamical models sometimes fail to represent observed teleconnection patterns associated with predictable modes of climate variability. As a result, model forecast skill may be reduced. We address this gap in skill through the application of a Bayesian postprocessing technique—the calibration, bridging, and merging (CBaM) method—which previously has been shown to improve probabilistic seasonal forecast skill over Australia. Calibration models developed from dynamical model reforecasts and observations are employed to statistically correct dynamical model forecasts. Bridging models use dynamical model forecasts of relevant climate modes (e.g., ENSO) as predictors of remote temperature and precipitation. Bridging and calibration …

Latitude And Longitude Dependence Of Ionospheric Tec And Magnetic Perturbations From Infrasonic-Acoustic Waves Generated By Strong Seismic Events, M. D. Zettergren, J. B. Snively

Publications

A numerical study of the effects of seismically generated acoustic waves in the ionosphere is conducted using a three-dimensional (3-D) ionospheric model driven by an axisymmetric neutral atmospheric model. A source consistent with the 2011 Tohoku earthquake initial ocean surface uplifting is applied to simulate the subsequent responses. Perturbations in electron density, ion drift, total electron content (TEC), and ground-level magnetic fields are examined. Results reveal strong latitude and longitude dependence of ionospheric TEC, and of ground-level magnetic field perturbations associated with acoustic wave-driven ionospheric dynamo currents. Results also demonstrate that prior two-dimensional models can capture dominant meridional responses of …

Aviation Weather Products In General Aviation: Interpretability And Usability Research Trends, Jacqueline Mcsorley, Jayde King, Beth Blickensderfer

General Aviation Weather Display Interpretation

As a result of advances in weather forecasting and technology, today’s General Aviation (GA) pilots have access to a wealth of aviation weather information. During pre-flight planning, GA pilots may access weather radar images, satellite pictures, winds, and forecast maps. During flight, pilots can access in-cockpit weather displays, as well as, handheld portable weather devices. Despite the increasing advancement and accessibility of weather displays, there is limited research addressing the interpretability of both in-cockpit and preflight weather displays. This is particularly concerning considering that preflight planning and poor product interpretability have been cited as possible contributing factors for GA weather …

Usability Analysis Of Convective Sigmets, Jackie Mcsorley, Beth Blickensderfer

General Aviation Weather Display Interpretation

• Introduction
• Methods
• Results

○ Interface Analysis: System Usability Scale

○ Workload Analysis: NASA-TLX

• Discussion
• Current Investigations

Preflight Weather Worksheet, Embry-Riddle Aeronautical University

Weather Training Modules

Preflight Weather Worksheet

• Big Picture
• Hazards
• Visibility

A New Model For Lifting Condensation Levels Estimation, Nihad E. Daidzic Ph.D., Sc.D.

International Journal of Aviation, Aeronautics, and Aerospace

Knowledge of and the ability to predict lifting condensation levels (LCL) is important ingredient in weather predictions, cloud formation, planetary albedo and Earth’s energy balance. It is also essential topic in aviation safety and flight operations. In this article, we derive a new model of LCL and compare it to some older commonly-used models. This includes also the recently published Romps’ (2017) model. The new model presented here includes dependence, however weak, of the surface atmospheric pressure and the specific humidity on the LCL height and temperature. Such is not the case with widely used models and expressions by Espy …

Urban Flow And Small Unmanned Aerial System Operations In The Built Environment, Kevin A. Adkins

International Journal of Aviation, Aeronautics, and Aerospace

The Federal Aviation Administration (FAA) has put forth a set of regulations (Part 107) that govern small unmanned aerial system (sUAS) operations. These regulations restrict unmanned aircraft (UA) from flying over people and their operation to within visual line of sight (VLOS). However, as new applications for unmanned aerial systems (UAS) are discovered, their capabilities improve, and regulations evolve, there is an increasing desire to undertake urban operations, such as urban air mobility, package delivery, infrastructure inspection, and surveillance. This built environment poses new weather hazards that include enhanced wind shear and turbulence. The smaller physical dimensions, lower mass and …

Adding Value To Numerical Weather Predictions For The Aviation Industry In South Africa., Quinton Jacobs Mr., Willem A. Landman Prof.

International Journal of Aviation, Aeronautics, and Aerospace

The main objective of this study is to determine whether human forecasters at the main airports of South Africa add value to the raw numerical weather prediction model output when they provide forecast services to the aviation industry. Dataset pairs of weather observations made at these airports and terminal aerodrome forecasts are constructed for three forecast systems: the human forecasters, persistence forecast and the raw output from the 12 km resolution Unified Model administered by the South African Weather Service. These three dataset pairs are independently evaluated by a forecast verification system developed at the South African Weather Service. A …

On Atmospheric Lapse Rates, Nihad E. Daidzic

International Journal of Aviation, Aeronautics, and Aerospace

We have derived and summarized and most important atmospheric temperature lapse rates. ALRs essentially govern vertical atmospheric air stability and creation of some cloud types. The sensitivity analysis of various atmospheric lapse rates and their dependence on actual ideal-gas air properties and gravitational attraction was conducted for the first time to the best of our knowledge. SALR, which has DALR as the upper asymptote, showed steepest decrease at around 9 degrees Celsius then flattening out and apparently approaching another asymptotic solution which has not been investigated as it falls outside of the terrestrial temperature range. ISA lapse rates are adopted …

Uas Flight Operations In Complex Terrain: Assessing The Agricultural Impact From Hurricane Maria In The Central Mountainous Region Of Puerto Rico, Kevin Adkins

Publications

Hurricane Maria struck Puerto Rico in September 2017 as a Category 4 storm causing major damage to infrastructure, agriculture and natural ecosystems, as well as the loss of many lives. Among the crops hardest hit was coffee, one of the most important crops in Puerto Rico. As a perennial system, coffee takes various production forms along a gradient from high shade/biodiversity coffee farms to low shade coffee monocultures and therefore offers an ideal means for the study of resistance and resilience of an agroecosystem to weather and climate disturbance. During the summer of 2018, 14 impacted farms across the production …

Vortex: A New Rocketexperiment To Studymesoscale Dynamics At The Turbopause, Gerald A. Lehmacher, Miguel F. Larsen, Michael J. Taylor, Jonathan B. Snively, Aroh Barjatya, Franz-Josef Lübken, Jorge L. Chau

Publications

The goal of this new investigation is to better understand gravity waves and their interactions as they propagate from the mesosphere into the lower thermosphere, to characterize the mesoscale wind field, and to identify regions of divergence, vorticity, and stratified turbulence. The Vorticity Experiment (VortEx) will comprise two salvoes of each two sounding rockets scheduled to be launched from Andøya Space Center, Norway in February 2022. The rockets will observe horizontally spaced wind profiles, neutral density and temperature profiles, and plasma densities. Additional information about the background conditions and mesoscale dynamics will be obtained by lidars, meteor radars and a …

A Remote Observatory For Geocoronal Hydrogen Emissions, Margaret A. Gallant

Doctoral Dissertations and Master's Theses

The Investigating Near Space Interaction Regions (INSpIRe) observatory is an adaptable research facility that is designed to use Fabry-Perot interferometer (FPI) to study the faint Balmer series emissions of the terrestrial upper thermosphere and exosphere, collectively known as the geocorona. This instrumentation is designed to be deployable to a clear-air site, necessitating remote operations of the entire observatory, including control and monitoring. The facility currently employs a siderostat to allow for pointing at sky targets, a pressure-tuned dual-etalon FPI to allow for high spectral resolution (R_80,000) measurements, and several charge-coupled device (CCD) imagers for guiding and collecting data. The environment …

Observations Of Reduced Turbulence And Wave Activity In The Arctic Middle Atmosphere Following The January 2015 Sudden Stratospheric Warming, Colin C. Triplett, Jintai Li, Richard L. Collins, Gerald A. Lehmacher, Aroh Barjatya, David C. Fritts, Et. Al.

Publications

Measurements of turbulence and waves were made as part of the Mesosphere-Lower Thermosphere Turbulence Experiment (MTeX) on the night of 25–26 January 2015 at Poker Flat Research Range, Chatanika, Alaska (65°N, 147°W). Rocket-borne ionization gauge measurements revealed turbulence in the 70- to 88-km altitude region with energy dissipation rates between 0.1 and 24 mW/kg with an average value of 2.6 mW/kg. The eddy diffusion coefficient varied between 0.3 and 134 m²/s with an average value of 10 m²/s. Turbulence was detected around mesospheric inversion layers (MILs) in both the topside and bottomside of the MILs. These …

On The Existence Of Ionospheric Feedback Instability In The Earth’S Magnetosphere-Ionosphere System, Anatoly V. Streltsov, Evgeny V. Mishin

Publications

The ionospheric feedback instability (IFI) has been considered one of the main generation mechanisms for large-amplitude ultralow frequency waves and small-scale field-aligned currents in the auroral and subauroral regions for more than 40 years. Sydorenko and Rankin (2017, https://doi.org/10.1002/2017GL073415) have recently challenged the very existence of the IFI for any realistic geophysical conditions in the Earth's ionosphere-magnetosphere system. Because this conclusion contradicts numerous theoretical, numerical, and experimental works successfully used IFI to explain and predict results from observations for more than four decades, it deserves special attention. We show that this conclusion is mainly based on the specific ionospheric …

On The Asymmetry Between Upward And Downward Field-Aligned Currents Interacting With The Ionosphere, A. V. Streltsov

Publications

The paper presents results from the numerical study of the magnetosphere-ionosphere interactions driven by the large-scale electric field in the magnetically conjugate, high-latitude regions of northern and southern hemispheres. Simulations of the two-fluid MHD model demonstrate that these interactions can lead to a generation of a system of small-scale, intense field-aligned currents with a significant difference in size and amplitude between the upward and downward currents. In particular, in both hemispheres, the downward currents (where the electrons are flowing from the ionosphere) become more narrow and intense than the adjacent upward currents. At high latitudes, the field-aligned currents are closely …

Interpreting Aviation Weather Products: Follow-Up Study With Aopa Members, Beth Blickensderfer, Thomas A. Guinn, Thomas Bob, Jayde King, Yolanda Ortiz, Nick Defilippis, Quirijn Berendschot, Jacqueline Mcsorley

General Aviation Weather Display Interpretation

Purpose

• Use the questions we developed in Phase I
• Include pilots that are more representative of GA (age, flight hours/experience); Collaborate with AOPA
• Examine: Knowledge about aviation weather products; Differences between levels of flight certificate and/or ratings

Assessing Ga Pilots' Preflight Weather Planning Mental Models, Yolanda Ortiz, Beth Blickensderfer, Thomas A. Guinn

General Aviation Weather Display Interpretation

Purpose, To assess GA Pilots' ability to:

• Obtain the Appropriate Weather Information
• Interpret the Data
• Apply the Information to a Given Flight Route

Aviation Weather Education: Challenges Using Current Faa Guidance, Thomas A. Guinn, Robert Thomas

Aviation Weather Training Research

Observed Challenges

• Incorrect product information
• Guidance not keeping pace with new products
• Multiple formats of same product
• Potentially unnecessary information
• Missing product information
• Limited focus on interpretation

Challenges For Flight Instructors Teaching Weather Information, Robert Thomas, Thomas A. Guinn

Aviation Weather Training Research

• Flight Instructors face a challenge when teaching/learning weather information
• Multiple overlapping resources for aviation weather
• AC takes longer timeframe to update –problem for quick updates of information

Momentum Flux Spectra Of A Mountain Wave Event Over New Zealand, Katrina Bossert, David C. Fritts, Christopher J. Heale, Stephen D. Eckermann, John M. C. Plane, Jonathan B. Snively, Bifford P. Williams, Iain M. Reid, Damian J. Murphy, Andrew J. Spargo, Andrew D. Mackinnon

Publications

During the Deep Propagating Gravity Wave Experiment (DEEPWAVE) 13 July 2014 research flight over the South Island of New Zealand, a multiscale spectrum of mountain waves (MWs) was observed. High-resolution measurements of sodium densities were available from ~70 to 100 km for the duration of this flight. A comprehensive technique is presented for obtaining temperature perturbations, T′, from sodium mixing ratios over a range of altitudes, and these T′ were used to calculate the momentum flux (MF) spectra with respect to horizontal wavelengths, λH, for each flight segment. Spectral analysis revealed MWs with spectral power centered at λH of ~80, …

Ultralow Frequency Electrodynamics Of Magnetosphere-Ionosphere Interactions Near The Plasmapause During Substorms, Anatoly V. Streltsov, Evgeny V. Mishin

Publications

Ultra low frequency (ULF) electromagnetic waves have been regularly observed by the CRRES, Cluster, and Van Allen Probes satellites near the plasmapause during substorms. Frequently, the small-scale waves are detected together with a large-scale quasi-stationary electric field collocating with mesoscale plasma flows penetrating into the plasmasphere. These observations suggest that the plasmapause plays an important role in the conversion of the kinetic energy of energetic particles moving toward the Earth from the reconnection site in the magnetotail into a large-scale electric field. The field penetrates along the magnetic field into the ionosphere and generates small-scale, shear Alfvén waves and field-aligned …

On The Short-Term Variability Of Turbulence And Temperature In The Winter Mesosphere, Gerald A. Lehmacher, Miguel F. Larsen, Richard L. Collins, Aroh Barjatya, Boris Strelnikov

Publications

Four mesosphere–lower thermosphere temperature and turbulence profiles were obtained in situ within ∼30 min and over an area of about 100 by 100 km during a sounding rocket experiment conducted on 26 January 2015 at Poker Flat Research Range in Alaska. In this paper we examine the spatial and temporal variability of mesospheric turbulence in relationship to the static stability of the background atmosphere. Using active payload attitude control, neutral density fluctuations, a tracer for turbulence, were observed with very little interference from the payload spin motion, and with high precision (%) at sub-meter resolution. The large-scale vertical temperature structure …

Impacts Of Anisotropy, Wave Heating, And Neutral Winds On High-Latitude Ionospheric Dynamics, Meghan R. Burleigh

Doctoral Dissertations and Master's Theses

Significant amounts of ionospheric plasma can be transported to high altitudes (ion upflow) in response to a variety of plasma heating and uplifting processes such as DC electric fields and precipitation. Once ions have been lifted to high altitudes, transverse ion acceleration by broadband ELF waves can give the upflowing ions sufficient energy for the mirror force to propel these ions to escape into the magnetosphere (ion outflow). In order to accurately examine the connection between upflow and outflow processes, a new two dimensional, anisotropic fluid model is developed.

The new model, named GEMINI-TIA, is based on a Bi-Maxwellian distribution …

Nonlinear Acoustic Waves Generated By Surface Disturbances And Their Effect On Lower Thermospheric Composition, Benedict Piñeyro

Doctoral Dissertations and Master's Theses

Recent nonlinear atmospheric models have provided important insight into acoustic waves generated by seismic events, which may steepen into shocks or saw-tooth trains while also dissipating strongly in the thermosphere. Although they have yielded results that agree with observations of ionospheric perturbations, dynamical models for the diffusive and stratified lower thermosphere often use single gas approximations with height-dependent physical properties (e.g. mean molecular weight, specific heats) that do not vary with time (fixed composition). This approximation is simpler and less computationally expensive than a true multi-fluid model, yet captures the important physical transition between molecular and atomic gases in the …

Book Review: Fundamentals Of International Aviation, Alan Bender

International Journal of Aviation, Aeronautics, and Aerospace

Not applicable.

A Diagnostic Metric For Predicting Tropical Cyclone And Mid-Latitude Floods, Jonathon Klepatzki, Shawn M. Milrad

Beyond: Undergraduate Research Journal

This study details a dynamic and thermodynamic metric (i.e., Extreme Flood Index [EFI]) designed to diagnose the frequency and intensity of extreme precipitation events associated with stagnant mid-latitude flow patterns (i.e., Rex blocks). As the global climate warms, rapid Arctic warming may be helping to slow the mid-latitude westerly jet stream, resulting in increased mid-latitude flow stagnation. The combination of long-duration ascent associated with easterly winds and warm moist air increases the severity of extreme precipitation events; as such, the EFI is specifically designed to detect this potent combination of ingredients. In 2013, a Rex block stalled a low-pressure system …

Thermal Removal Of Carbon Dioxide From The Atmosphere: Energy Requirements And Scaling Issues, Ted Von Hippel

Publications

I conduct a systems-level study of direct air capture of CO2 using techniques from thermal physics. This system relies on a combination of an efficient heat exchanger, radiative cooling, and refrigeration, all at industrial scale and operated in environments at low ambient temperatures. While technological developments will be required for such a system to operate efficiently, those developments rest on a long history of refrigeration expertise and technology, and they can be developed and tested at modest scale. I estimate that the energy required to remove CO2 via this approach is comparable to direct air capture by other techniques. The …

Error Analysis Of Multi-Needle Langmuir Probe Measurement Technique, Aroh Barjatya, William Merritt

Publications

Multi-needle Langmuir probe is a fairly new instrument technique that has been flown on several recent sounding rockets and is slated to fly on a subset of QB50 CubeSat constellation. This paper takes a fundamental look into the data analysis procedures used for this instrument to derive absolute electron density. Our calculations suggest that while the technique remains promising, the current data analysis procedures could easily result in errors of 50% or more. We present a simple data analysis adjustment that can reduce errors by at least a factor of five in typical operation.