Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Embry-Riddle Aeronautical University

2020

Atmospheric Sciences

Articles 1 - 9 of 9

Full-Text Articles in Physical Sciences and Mathematics

Gravity Waves, Na Lidar, Yafang Guo, Alan Z. Liu Dec 2020

Gravity Waves, Na Lidar, Yafang Guo, Alan Z. Liu

Publications

Vertical energy transports due to dissipating gravity waves in the mesopause region (85–100 km) are analyzed using over 400 h of observational data obtained from a narrow-band sodium wind-temperature lidar located at Andes Lidar Observatory (ALO), Cerro Pachón (30.25°S, 70.73°W), Chile. Sensible heat flux is directly estimated using measured temperature and vertical wind; energy flux is estimated from the vertical wavenumber and frequency spectra of temperature perturbations; and enthalpy flux is derived based on its relationship with sensible heat and energy fluxes. Sensible heat flux is mostly downward throughout the region. Enthalpy flux exhibits an annual oscillation with maximum downward …

Go to article

Kelvin-Helmholtz Billow Interactions And Instabilities In The Mesosphere Over The Andes Lidar Observatory: 1. Observations, J. H. Hecht, R. L. Walterscheid, A. Z. Liu, D. C. Fritts, L. J. Gelinas, R. J. Rudy Nov 2020

Kelvin-Helmholtz Billow Interactions And Instabilities In The Mesosphere Over The Andes Lidar Observatory: 1. Observations, J. H. Hecht, R. L. Walterscheid, A. Z. Liu, D. C. Fritts, L. J. Gelinas, R. J. Rudy

Publications

A very high spatial resolution (∼25 m pixel at 90 km altitude) OH airglow imager was installed at the Andes Lidar Observatory on Cerro Pachón, Chile, in February 2016. This instrument was collocated with a Na wind-temperature lidar. On 1 March 2016, the lidar data showed that the atmosphere was dynamically unstable before 0100 UT and thus conducive to the formation of Kelvin-Helmholtz instabilities (KHIs). The imager revealed the presence of a KHI and an apparent atmospheric gravity wave (AGW) propagating approximately perpendicular to the plane of primary KHI motions. The AGW appears to have induced modulations of the shear …

Go to article

Large Scale Upper-Level Precursors For Dust Storm Formation Over North Africa And Poleward Transport To The Iberian Peninsula. Part I: An Observational Analysis, J.A. G. Orza, Michael L. Kaplan, S. Dhital, S. Fiedler Sep 2020

Large Scale Upper-Level Precursors For Dust Storm Formation Over North Africa And Poleward Transport To The Iberian Peninsula. Part I: An Observational Analysis, J.A. G. Orza, Michael L. Kaplan, S. Dhital, S. Fiedler

Publications

The analysis of three extreme African dust outbreaks over the Iberian Peninsula (IP) shows that a double Rossby wave breaking (RWB) process in the polar jet (PJ) creates the conditions for dust storm formation over subtropical deserts in North Africa and the restructuring of upper-level air flows critical for the dust transport poleward after ablation. Two consecutive anticyclonic RWBs initiate over the IP and the adjacent Atlantic, the first commencing 10 days before dust reaches the IP and the second three to five days later. The first RWB becomes quasi-stationary over the eastern Mediterranean when the second RWB develops. In …

Go to article

Observations Of An Extreme Atmospheric River Storm With A Diverse Sensor Network, B. J. Hatchett, Michael L. Kaplan, Q. Cao, P. B. Dawson, C. J. Ellis, Et Al. Jul 2020

Observations Of An Extreme Atmospheric River Storm With A Diverse Sensor Network, B. J. Hatchett, Michael L. Kaplan, Q. Cao, P. B. Dawson, C. J. Ellis, Et Al.

Publications

Observational networks enhance real‐time situational awareness for emergency and water resource management during extreme weather events. We present examples of how a diverse, multitiered observational network in California provided insights into hydrometeorological processes and impacts during a 3‐day atmospheric river storm centered on 14 February 2019. This network, which has been developed over the past two decades, aims to improve understanding and mitigation of effects from extreme storms influencing water resources and natural hazards. We combine atmospheric reanalysis output and additional observations to show how the network allows: (1) the validation of record cool season precipitable water observations over southern …

Go to article

Use Of Lidar Data To Investigate The Influence Of Bottom Friction Coefficients For Storm Surge Modeling Of Hurricane Michael In The Florida Panhandle, Sky Comarsh White Jul 2020

Use Of Lidar Data To Investigate The Influence Of Bottom Friction Coefficients For Storm Surge Modeling Of Hurricane Michael In The Florida Panhandle, Sky Comarsh White

Doctoral Dissertations and Master's Theses

Current storm surge modeling typically uses local land use land cover (LULC) maps coupled with lookup tables to parameterize surface roughness because the process is defensible and easily automated at the regional scale. However, this is not a truly accurate method since LULC data is generalized for an area and often contains misclassifications. Intra-class variability is also a concern as variations in obstacle density within LULC classifications are prominent at typical storm surge model resolution scales ranging from 20-meters to 200-meters in the floodplain. Using lidar data, topography and the 3-dimensional structure of above-ground obstructions can be more accurately characterized, …

Go to article

Evidence For Horizontal Blocking And Reflection Of A Small-Scale Gravity Wave In The Mesosphere, N. R. Criddle, C. Heale, J. Snively, P. -D. Pautet, T. Yuan, Y. Zhao, M. J. Taylor Apr 2020

Evidence For Horizontal Blocking And Reflection Of A Small-Scale Gravity Wave In The Mesosphere, N. R. Criddle, C. Heale, J. Snively, P. -D. Pautet, T. Yuan, Y. Zhao, M. J. Taylor

Publications

The variations of the horizontal phase velocity of an internal gravity wave, generated by wave “blocking” or “reflection” due to an inhomogeneous wind field, have been predicted theoretically and numerically investigated but had yet to be captured experimentally. In this paper, through a collaborative observation campaign using a sodium (Na) Temperature/Wind lidar and a collocated Advanced Mesospheric Temperature Mapper (AMTM) at Utah State University (USU), we report the first potential evidence of such a unique gravity wave process. The study shows that a small-scale wave, captured by the AMTM, with initial observed horizontal phase velocity of 37 ± 5 m/s …

Go to article

Modeling Of Ionospheric Responses To Atmospheric Acoustic And Gravity Waves Driven By The 2015 Nepal M W 7.8 Gorkha Earthquake, P. A. Inchin, J. B. Snively, M. D. Zettergren, A. Komjathy, O. P. Verkhoglyadova, S. Tulasi Ram Feb 2020

Modeling Of Ionospheric Responses To Atmospheric Acoustic And Gravity Waves Driven By The 2015 Nepal M W 7.8 Gorkha Earthquake, P. A. Inchin, J. B. Snively, M. D. Zettergren, A. Komjathy, O. P. Verkhoglyadova, S. Tulasi Ram

Publications

Near- and far-field ionospheric responses to atmospheric acoustic and gravity waves (AGWs) generated by surface displacements during the 2015 Nepal 7.8 Gorkha earthquake are simulated. Realistic surface displacements driven by the earthquake are calculated in three-dimensional forward seismic waves propagation simulation, based on kinematic slip model. They are used to excite AGWs at ground level in the direct numerical simulation of three-dimensional nonlinear compressible Navier-Stokes equations with neutral atmosphere model, which is coupled with a two-dimensional nonlinear multifluid electrodynamic ionospheric model. The importance of incorporating earthquake rupture kinematics for the simulation of realistic coseismic ionospheric disturbances (CIDs) is demonstrated and …

Go to article

Development Of A Sensor Suite For Atmospheric Boundary Layer Measurement With A Small Multirotor Unmanned Aerial System, Kevin A. Adkins, Christopher J. Swinford, Peter D. Wambolt, Gordon Bease Jan 2020

Development Of A Sensor Suite For Atmospheric Boundary Layer Measurement With A Small Multirotor Unmanned Aerial System, Kevin A. Adkins, Christopher J. Swinford, Peter D. Wambolt, Gordon Bease

International Journal of Aviation, Aeronautics, and Aerospace

Small unmanned aerial systems (sUAS) are increasingly being used to conduct atmospheric research. Because of the dynamic nature and inhomogeneity of the atmospheric boundary layer (ABL), the ability of instrumented sUAS to make on-demand 3-dimensional high-resolution spatial measurements of atmospheric parameters makes them particularly suited to ABL investigations. Both fixed-wing and multirotor sUAS have been used for ABL investigations. Most investigations to date have included in-situ measurement of thermodynamic quantities such as temperature, pressure and humidity. When wind has been measured, a variety of strategies have been used. Two of the most popular techniques have been deducing wind from inertial …

Go to article

A Proposed Taxonomy For General Aviation Pilot Weather Education And Training, John M. Lanicci, Thomas A. Guinn, Jayde M. King, Beth Blickensderfer, Robert Thomas, Yolanda Ortiz Jan 2020

A Proposed Taxonomy For General Aviation Pilot Weather Education And Training, John M. Lanicci, Thomas A. Guinn, Jayde M. King, Beth Blickensderfer, Robert Thomas, Yolanda Ortiz

Journal of Aviation/Aerospace Education & Research

As General Aviation (GA) safety continues to remain a focus of the aviation community, GA pilot weather education and training continues to be an active area of interest within the research community. This study introduces a taxonomy for organizing GA pilot weather education and training materials that was originally conceived as part of the FAA’s Weather Technology In the Cockpit research program. The taxonomy is built upon three main knowledge categories, or tiers:1) Weather Phenomena (which includes hazards); 2) Weather Hazard Products; and 3) Weather Hazard Product Sources and their Application. The concept behind the categorization is to link knowledge …

Go to article