Atmospheric Sciences Commons^™

Unmanned Aerial Systems For Monitoring Trace Tropospheric Gases, Travis J. Schuyler, Marcelo I. Guzman

Chemistry Faculty Publications

The emission of greenhouse gases (GHGs) has changed the composition of the atmosphere during the Anthropocene. Accurately documenting the sources and magnitude of GHGs emission is an important undertaking for discriminating the contributions of different processes to radiative forcing. Currently there is no mobile platform that is able to quantify trace gases at altitudes(UASs) can be deployed on-site in minutes and can support the payloads necessary to quantify trace gases. Therefore, current efforts combine the use of UASs available on the civilian market with inexpensively designed analytical systems for monitoring atmospheric trace gases. In this context, this perspective introduces the …

Quantification Of Precipitation Asymmetries In Tropical Cyclones And Their Relationship To Storm Intensity Changes Using Trmm Data, Yongxian Pei

FIU Electronic Theses and Dissertations

The climatology of precipitation asymmetries in Tropical Cyclones (TCs) and their relationship to TC intensity changes using 16 years of data from the Tropical Rainfall Measuring Mission (TRMM) satellite. TC Inner core precipitation asymmetries were quantified using the Fourier wavenumber decomposition method upon the pixel level data of 3,542 TRMM TMI overpasses. Composites of wavenumber–1 and wavenumber 1–6 total precipitation asymmetries were constructed to show the distribution pattern under different storm motion speed, vertical wind shear and the combined effects of varying vertical wind shear and storm motion. Results indicate that motion–relative total precipitation asymmetry is located down–motion. The phase …

Observation And Modeling Of Gravity Wave Propagation Through Reflection And Critical Layers Above Andes Lidar Observatory At Cerro Pachón, Chile, Bing Cao, Christopher J. Heale, Yafang Guo, Alan Z. Liu, Jonathan B. Snively

Jonathan B. Snively

A complex gravity wave event was observed from 04:30 to 08:10 UTC on 16 January 2015 by a narrow-band sodium lidar and an all-sky airglow imager located at Andes Lidar Observatory (ALO) in Cerro Pachón (30.25∘S, 70.73∘W), Chile. The gravity wave packet had a period of 18–35 min and a horizontal wavelength of about 40–50 km. Strong enhancements of the vertical wind perturbation, exceeding10 m s−1, were found at ∼90 km and ∼103 km, consistent with nearly evanescent wave behavior near a reflection layer. A reduction in vertical wavelength was found as the phase speed approached the background wind speed …

Numerical Modeling Of A Multiscale Gravity Wave Event And Its Airglow Signatures Over Mount Cook, New Zealand, During The Deepwave Campaign, C. J. Heale, K. Bossert, J. B. Snively, D. C. Fritts, P. -D. Pautet, M. J. Taylor

Jonathan B. Snively

A 2-D nonlinear compressible model is used to simulate a large-amplitude, multiscale mountain wave event over Mount Cook, NZ, observed as part of the Deep Propagating Gravity Wave Experiment (DEEPWAVE) campaign and to investigate its observable signatures in the hydroxyl (OH) layer. The campaign observed the presence of a �x = 200 km mountain wave as part of the 22nd research flight with amplitudes of >20 K in the upper stratosphere that decayed rapidly at airglow heights. Advanced Mesospheric Temperature Mapper (AMTM) showed the presence of small-scale (25–28 km) waves within the warm phase of the large mountain wave. The …

Nonlinear Ionospheric Responses To Large-Amplitude Infrasonic-Acoustic Waves Generated By Undersea Earthquakes, M. D. Zettergren, J. B. Snively, A. Komjathy, O. P. Verkhoglyadova

Jonathan B. Snively

Numerical models of ionospheric coupling with the neutral atmosphere are used to investigate perturbations of plasma density, vertically integrated total electron content (TEC), neutral velocity, and neutral temperature associated with large-amplitude acoustic waves generated by the initial ocean surface displacements from strong undersea earthquakes. A simplified source model for the 2011 Tohoku earthquake is constructed from estimates of initial ocean surface responses to approximate the vertical motions over realistic spatial and temporal scales. Resulting TEC perturbations from modeling case studies appear consistent with observational data, reproducing pronounced TEC depletions which are shown to be a consequence of the impacts of …

The Clean Air Act And Its Impact On Ground Level Ozone Pollution Levels In Los Angeles, California, Rebecca G. Ford

Honors Theses

Ozone (O₃) occurs naturally as a protective, ultraviolet radiation-shielding “Ozone Layer” in the Stratosphere and as a photochemically produced pollutant in the Troposphere. The Clean Air Act (CAA) of 1970 regulates the emission and concentration of O₃ and five other atmospheric pollutants. Since the signing of the CAA, the ongoing question has been whether or not the National Ambient Air Quality Standards (NAAQS) and regulatory policies have had an effect on decreasing O₃ concentration. The Los Angeles metropolitan area is a prime example of how O₃ can be a public health hazard, and taint a …

Droughtscape- Fall 2017, National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

CONTENTS

Drought worsens in northern Great Plains............. 2

Drought takes toll on ag, livestock................ 4

Study examines ag advisors’ views on climate change............... 5

New drought definition could lead to better preparation.............. 6

McCook takes big steps toward drought readiness.............8

Group hopes to map drought planning process for Korea............9

South African researcher working to forecast drought.................. 10

Cultivating drought preparedness in South Africa.............. 12

Life In Hampton Roads: Sea Level Rise And Flooding, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

A Near-Global Atmospheric Distribution Of N2o Isotopologues, Peter F. Bernath, Mahdi Yousefi, Eric Buzan, Chris D. Boone

Chemistry & Biochemistry Faculty Publications

The distributions of the four most abundant isotopologues and isotopomers (N₂O, ¹⁵NNO, N¹⁵NO, and NN¹⁸O of nitrous oxide have been measured in the Earth's stratosphere by infrared remote sensing with the Atmospheric Chemistry Experiment (ACE) Fourier transform spectrometer. These satellite observations have provided a near-global picture of N₂O isotopic fractionation. The relative abundances of the heavier species increase with altitude and with latitude in the stratosphere as the air becomes older. The heavy isotopologues are enriched by 20-30% in the upper stratosphere and even more over the poles. These observations are …

The Influence Of Recurrent Modes Of Climate Variability On The Occurrence Of Monthly Temperature Extremes Over South America, Paul C. Loikith, Judah Detzer, Carlos R. Mechoso, Huikyo Lee, Armineh Barkhordarian

Geography Faculty Publications and Presentations

The associations between extreme temperature months and four prominent modes of recurrent climate variability are examined over South America. Associations are computed as the percent of extreme temperature months concurrent with the upper and lower quartiles of the El Niño–Southern Oscillation (ENSO), the Atlantic Niño, the Pacific Decadal Oscillation (PDO), and the Southern Annular Mode (SAM) index distributions, stratified by season. The relationship is strongest for ENSO, with nearly every extreme temperature month concurrent with the upper or lower quartiles of its distribution in portions of northwestern South America during some seasons. The likelihood of extreme warm temperatures is enhanced …

Collaborative Research: Synergistic Merging Of Traditional Aeronomy With Targeted High-Frequency (Hf) Heating Diagnostics, Herbert C. Carlson

Funded Research Records

No abstract provided.

Oblique Longwave Infrared Atmospheric Compensation, Daniel S. O'Keefe

Theses and Dissertations

This research introduces two novel oblique longwave infrared atmospheric compensation techniques for hyperspectral imagery, Oblique In-Scene Atmospheric Compensation (OISAC) and Radiance Detrending (RD). Current atmospheric compensation algorithms have been developed for nadir-viewing geometries which assume that every pixel in the scene is affected by the atmosphere in nearly the same manner. However, this assumption is violated in oblique imaging conditions where the transmission and path radiance vary continuously as a function of object-sensor range, negatively impacting current algorithms in their ability to compensate for the atmosphere. The techniques presented here leverage the changing viewing conditions to improve rather than hinder …

Ionospheric Gravity Waves Driven By Oceanic Gravity Waves In Resonance: A Modeling Study In Search Of Their Spectra, Michael P. Hickey, Yonghui Yu

Publications

Ionospheric observations associated with the 2011 Tohoku tsunami have revealed gravity waves having spectral characteristics that depend on their proximity to the epicenter. There is a preponderance of medium-scale waves in the vicinity of the epicenter, a significant bifurcation into short- and long-period waves over the Hawaiian archipelago, and a narrow and rich spectrum of waves over the West Coast and inland of the United States (U.S.). Guided by these previous observations, we consider wave sources as triads of nonlinearly interacting oceanic gravity waves, whose wave parameters satisfy resonant conditions. These waves are simulated using a 2-D nonlinear model describing …

Mobile Radar As An Undergraduate Education And Research Tool: The Erau C-Breese Field Experience With The Doppler On Wheels, Shawn M. Milrad, Christopher G. Herbster

Publications

Embry-Riddle Aeronautical University Convective-Boundary Research Engaging Educational Student Experiences (ERAU C-BREESE) was an 18-day National Science Foundation (NSF)-funded educational Doppler on Wheels (DOW) deployment through the Center for Severe Weather Research in May 2015. ERAU C-BREESE had three primary areas of focus: meteorological field observations and research, undergraduate experiential learning, and local community outreach. ERAU undergraduate meteorology students had the unique opportunity to forecast for, collect, and analyze field measurements of sea-breeze processes and convection. The scientific objectives of ERAU C-BREESE were to forecast, observe, and analyze central Florida sea-breeze processes and thunderstorms by combining a DOW with more traditional …

Umphlett Qci Sept 2017, Natalie Umphlett

HPRCC Personnel Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Drought

Wildfires Impact Montana and Beyond

Kansas City, MO Area Flooding

Numerous Impacts to Agriculture

3-Month Precipitation and Temperature Outlooks

U.S. Seasonal Drought Outlook

Characteristics Of Mesospheric Gravity Waves Over Antarctica Observed By Angwin (Antarctic Gravity Wave Instrument Network) Imagers Using 3-D Spectral Analyses, Takashi S. Matsuda, Takuji Nakamura, Mitsumu K. Ejiri, Masaki Tsutsumi, Yoshihiro Tomikawa, Michael J. Taylor, Yucheng Zhao, Pierre-Dominique Pautet, Damian J. Murphy, Tracy Moffat-Griffin

Publications

We have obtained horizontal phase velocity distributions of the gravity waves around 90 km from four Antarctic airglow imagers, which belong to an international airglow imager/instrument network known as ANGWIN (Antarctic Gravity Wave Instrument Network). Results from the airglow imagers at Syowa (69°S, 40°E), Halley (76°S, 27°W), Davis (69°S, 78°E), and McMurdo (78°S, 167°E) were compared, using a new statistical analysis method based on 3-D Fourier transform (Matsuda et al., 2014) for the observation period between 7 April and 21 May 2013. Significant day-to-day and site-to-site differences were found. The averaged phase velocity spectrum during the observation period showed preferential …

Major Hurricane Impact: Is Hampton Roads Ready?, Jon Cawley

News Items

No abstract provided.

Odu Researcher: Hampton Roads A Poster-Child For Sea Level Rise Threat, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

Ice Nucleation Parameterization And Relative Humidity Distribution In Idealized Squall-Line Simulations, Minghui Diao, George Bryan, Hugh Morrison, Jorgen Jensen

Faculty Publications, Meteorology and Climate Science

Output from idealized simulations of a squall line are compared with in situ aircraft-based observations from the Deep Convective Clouds and Chemistry campaign. Relative humidity distributions around convection are compared between 1-Hz aircraft observations (≈250-m horizontal scale) and simulations using a double-moment bulk microphysics scheme at three horizontal grid spacings: Δx = 0.25, 1, and 4 km. The comparisons focus on the horizontal extent of ice supersaturated regions (ISSRs), the maximum and average relative humidity with respect to ice (RHi) in ISSRs, and the ice microphysical properties during cirrus cloud evolution, with simulations at 0.25 and 1 km providing better …

Machine Learning Algorithms For Automated Satellite Snow And Sea Ice Detection, George Bonev

Dissertations, Theses, and Capstone Projects

The continuous mapping of snow and ice cover, particularly in the arctic and poles, are critical to understanding the earth and atmospheric science. Much of the world's sea ice and snow covers the most inhospitable places, making measurements from satellite-based remote sensors essential. Despite the wealth of data from these instruments many challenges remain. For instance, remote sensing instruments reside on-board different satellites and observe the earth at different portions of the electromagnetic spectrum with different spatial footprints. Integrating and fusing this information to make estimates of the surface is a subject of active research.

In response to these challenges, …