Atmospheric Sciences Commons^™

Statistical Analysis Of The Usu Lidar Data Set With Reference To Mesospheric Solar Response And Cooling Rate Calculation, With Analysis Of Statistical Issues Affecting The Regression Coefficients, Troy Alden Wynn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Though the least squares technique has many advantages, its possible limitations as applied in the atmospheric sciences have not yet been fully explored in the literature. The assumption that the atmosphere responds either in phase or out of phase to the solar input is ubiquitous. However, our analysis found this assumption to be incorrect. If not properly addressed, the possible consequences are bias in the linear trend coefficient and attenuation of the solar response coefficient.

Using USU Rayleigh lidar temperature data, we found a significant phase offset to the solar input in the temperatures that varies ±5 years depending on …

Architecture, Modeling, And Analysis Of A Plasma Impedance Probe, Magathi Jayaram

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Variations in ionospheric plasma density can cause large amplitude and phase changes in the radio waves passing through this region. Ionospheric weather can have detrimental effects on several communication systems, including radars, navigation systems such as the Global Positioning Sytem (GPS), and high-frequency communications. As a result, creating models of the ionospheric density is of paramount interest to scientists working in the field of satellite communication.

Numerous empirical and theoretical models have been developed to study the upper atmosphere climatology and weather. Multiple measurements of plasma density over a region are of marked importance while creating these models. The lack …

Characterization Of Pollen Particles Using Lidar, Leda Sox

Graduate Student Posters

We have observed pollen in the local troposphere using the depolarization capabilities of a LIDAR (Light Detection and Ranging) system. The polarization characteristics of the received LIDAR signal, along with supplemental pollen forecast data, allowed me to characterize the shape of the pollen particles.

The First Ten Months Of Investigation Of Gravity Waves And Temperature Variability Over The Andes, Jonathan Pugmire, Neal Criddle, Michael J. Taylor, P. D. Pautet, Yucheng Zhao

Graduate Student Posters

The Andes region is an excellent natural laboratory for investigating gravity wave influences on the Upper Mesospheric and Lower Thermospheric (MLT) dynamics. The instrument suite that comprised the very successful Maui-MALT program was recently re-located to a new Andes Lidar Observatory (ALO) located at Cerro Pachon, Chile to obtain in-depth seasonal measurements of MLT dynamics over the Andes mountains. As part of the instrument set the Utah State University CEDAR Mesospheric Temperature Mapper (MTM) has operated continuously since August 2009 measuring the near infrared OH(6,2) band and the O2(0,1) Atmospheric band intensity and temperature perturbations. This poster focuses on an …

First Year Investigation Of Gravity Waves And Temperature Variability Over The Andes, Jonathan Pugmire, Neal R. Criddle, Michael J. Taylor, Dominique Pautet, Yucheng Zhao

Graduate Student Presentations

The Andes region is an excellent natural laboratory for investigating gravity wave influences on the Upper Mesospheric and Lower Thermospheric (MLT) dynamics: during the summer months the dominant gravity waves result from deep convection arising from severe thunderstorms over the continent to the east. In winter this convective activity is expected to be replaced by strong orographic forcing due to intense prevailing zonal winds blowing eastward from the Pacific Ocean and suddenly encountering the towering Andes mountain range (6000m). This creates large amplitude mountain waves that have been measured well into the stratosphere and most recently penetrate occasionally into the …

Release Of Mercury Halides From Kcl Denuders In The Presence Of Ozone, Seth N. Lyman, Daniel A. Jaffe, Mae S. Gustin

USU Uintah Basin Faculty Publications

KCl-coated denuders have become a standard method for measurement of gaseous oxidized mercury, but their performance has not been exhaustively evaluated, especially in field conditions. In this study, KCl-coated and uncoated quartz denuders loaded with HgCl₂ and HgBr₂ lost 29–55% of these compounds, apparently as elemental mercury, when exposed to ozone (range of 6–100 ppb tested). This effect was also observed for denuders loaded with gaseous oxidized mercury at a field site in Nevada (3–37% of oxidized mercury lost). In addition, collection efficiency decreased by 12–30% for denuders exposed to 50 ppb ozone during collection of HgCl_{2 …}

Investigating Small-Scale Dynamical Features In The Mesopause Region, Deepak B. Simkhada

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Utilizing analyses of observational data, we performed a detailed study to investigate short-period atmospheric gravity waves and ripples, and instabilities in the mesopause region. Recent coordinated measurements from Haleakala Observatory, Maui, HI via airglow wave imaging, meteor wind radar, and Na wind temperature lidar have provided a unique dataset for this study. Gravity waves generated in the lower atmosphere propagate energy upwards into the mesosphere and lower thermosphere region where they modulate the airglow emissions, and later break and deposit their momentum, causing significant perturbations in winds and temperatures. Ripples, on the other hand, are likely generated by localized shear …

Field And Smog Chamber Studies Of Agricultural Emissions And Reaction Products, Derek J. Price

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agricultural emissions are an important contributor to atmospheric aerosol. These emissions include nitrogen containing organic compounds, primarily as amines, which have not been well investigated to date. Although there have been several studies that have looked at the emission of gas phase amines, there are only a few studies that have focused on ambient amine-based aerosol. There have also only been a handful of smog chamber studies that have investigated amine aerosol chemistry. Kinetic studies have looked at the reactions of amines with OH and ozone. However, amine reactions with nitrate radical (NO₃) are not well understood. Several …

Intercomparison Of Prism And Daymet Temperature Interpolation From 1980 To 2003, Rebecca A. Scully

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As ecosystem modeling becomes increasingly integrated with Geographic Information Systems (GIS) there is a rise in demand for spatially and temporally continuous meteorological data. But in order to justify management decisions or to provide robust scientific insights, the accuracy of meteorological data used as model input must be thoroughly quantified. Current methods to create spatially continuous climate data from discrete weather station data include inverse distance weighting, geostatistical techniques such as kriging and splines, local regression models such as Parameter-Elevation Regression on Independent Slope Model (PRISM) and Daymet, and regional regression models. For the conterminous United States, PRISM and Daymet …

Temperature Trends And Episodic Changes Of The Middle Atmosphere Over Logan Utah With Consideration To Model Specification, Troy A. Wynn, Vincent B. Wickwar

Reports

A summary of the linear trends estimated from the USU Rayleigh Lidar (41.74o N, 118oW) temperature data set. The data set covers a time span from September, 1993 to August, 2003 and an altitude range of 45 to 80 km. The data set includes 584 data points at 45 km to 580 data points at 80 km. Cooling trend profiles are calculated and compared to results from other researchers. Collinearity and bias are also considered as issues that could affect the regression results. Also considered is the possibility that the Mt. Pinatubo eruption has influenced temperature trend estimates. This is …

A Passive Sampler For Ambient Gaseous Oxidized Mercury Concentrations, Seth N. Lyman, Mae Sexauer Gustin, Eric M. Prestbo

USU Uintah Basin Faculty Publications

This paper reports on the development of a passive sampler for estimating gaseous oxidized mercury concentrations. Atmospheric gaseous oxidized mercury concentrations calculated from passive sampler data were correlated with those obtained using an automated analyzer (r2 = 0.71, p < 0.01, n = 110 for one-week deployments; r2 = 0.89, p < 0.01, n = 22 for two-week deployments). Sampler uptake was not significantly affected by changes in temperature, humidity, or ozone concentration, but it was slightly dependent on wind speed. As such, an equation for correcting data due to this factor was developed based on wind tunnel and field data. The detection limit for a two-week sampler deployment was ∼5 pg m−3. Field data collected in Nevada and the southeastern United States showed these samplers are useful for investigating spatial and temporal variability in gaseous oxidized mercury concentrations.

Intra-Annual Comparison Of Mesospheric Gravity Waves Over Halley And Rothera Stations, Antarctica, Jonathan Pugmire, Michael J. Taylor, K. Nielsen, A. Wall, J. Thompson, P. D. Pautet

Graduate Student Posters

No abstract provided.

Atmospheric Mercury Concentrations And Speciation Measured From 2004 To 2007 In Reno, Nevada, Usa, Seth N. Lyman, Mae Sexauer Gustin

USU Uintah Basin Faculty Publications

Atmospheric elemental, reactive and particulate mercury (Hg) concentrations were measured north of downtown Reno, Nevada, USA from November 2004 to November 2007. Three-year mean and median concentrations for gaseous elemental Hg (Hg0) were 1.6 and 1.5 ng m−3 (respectively), similar to global mean Hg0 concentrations. The three-year mean reactive gaseous Hg (RGM) concentration (26 pg m−3) was higher than values reported for rural sites across the western United States. Well defined seasonal and daily patterns in Hg0 and RGM concentrations were observed, with the highest Hg0 concentrations measured in winter and early morning, and RGM concentrations being greatest in the …

Testing And Application Of Surrogate Surfaces For Understanding Potential Gaseous Oxidized Mercury Dry Deposition, Seth N. Lyman, Mae Sexauer Gustin, Eric M. Prestbo, Phillip I. Kilner, Eric Edgerton, Ben Hartsell

USU Uintah Basin Faculty Publications

Currently there is no standard method for measurement of atmospheric mercury dry deposition. While all operationally defined forms of atmospheric mercury (elemental, oxidized, and particulate) can be dry deposited, oxidized forms are of concern due to high deposition velocities, water solubility, and reactivity. This paper describes the development of a surrogate surface for characterizing potential dry deposition of gaseous oxidized mercury (GOM). Laboratory tests showed that the surface collected HgCl2, HgBr2, and HgO with equal efficiency, and deposition was not significantly influenced by temperature, humidity, or ozone concentrations. Deposition of mercury to surfaces in field deployments was correlated with GOM …

Impact Of The Intraseasonal Variability Of Large-Scale Circulation Over The Western North Pacific On The Characteristics Of Tropical Cyclone Track, T. C. Chen, Shih-Yu (Simon) Wang, M. C. Yen, A. J. Clark

Plants, Soils, and Climate Faculty Publications

The life cycle of the Southeast Asian–western North Pacific monsoon circulation is established by the northward migrations of the monsoon trough and the western Pacific subtropical anticyclone, and is reflected by the intraseasonal variations of mo nsoon westerlies and trad e easterlies in the form of an east–west seesaw oscillation. In this paper, an effort is made to disclose the influence of this monsoon circulation on tropical cyclone tracks during its different ph ases using composite charts of large-scale circulation for certain types of tracks. A majority of straight-moving (recurving) tropical cyclones appear during weak (strong) monsoon west- erlies and …

The Spread-F Experiment (Spreadfex): Program Overview And First Results, David C. Fritts, M. A. Abdu, B. R. Batista, I. S. Batista, P. P. Batista, R. Buriti, B. R. Clemesha, T. Dautermann, E. De Paula, B. J. Fechine, Bela Fejer, D. Gobbi, J. Haase, F. Kamalabadi, B. Laughman, L. M. Lima, H. L. Liu, A. Medeiros, Pierre-Dominique Pautet, D. M. Riggin, F. São Sabbas, J. H. A. Sobral, P. Stamus, H. Takahashi, Michael J. Taylor, Sharon L. Vadas, C. M. Wrasse

Publications

We performed an extensive experimental campaign (the spread F Experiment, or SpreadFEx) from September to November 2005 to attempt to define the role of neutral atmosphere dynamics, specifically wave motions propagating upward from the lower atmosphere, in seeding equatorial spread F and plasma bubbles extending to higher altitudes. Campaign measurements focused on the Brazilian sector and included ground-based optical, radar, digisonde, and GPS measurements at a number of fixed and temporary sites. Related data on convection and plasma bubble structures were also collected by GOES 12 and the GUVI instrument aboard the TIMED satellite. Initial results of our analyses of …

Rayleigh-Lidar Observations Of Mesospheric Gravity Wave Activity Above Logan, Utah, Durga N. Kafle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A Rayleigh-scatter lidar operated from Utah State University (41.7°N, 111.8°W) for a period spanning 11 years ― 1993 through 2004. Of the 900 nights observed, data on 150 extended to 90 km or above. They were the ones used in these studies related to atmospheric gravity waves (AGWs) between 45 and 90 km. This is the first study of AGWs with an extensive data set that spans the whole mesosphere. Using the temperature and temperature gradient profiles, we produced a climatology of the Brunt-Väisälä (buoyancy) angular frequency squared, N² (rad/s)². The minimum and maximum values of N …

Rayleigh-Lidar Observations Of Mesospheric Instabilities, Gabriel C. Taylor, Durga N. Kafle, Vincent B. Wickwar

Posters

From 1993 to 2004 the Utah State University Rayleigh lidar, known as the USU green laser, collected 900 nights of data from the mesosphere (45-90 km). From these observations profiles of relative neutral densities and absolute temperatures were derived. Usually, the atmosphere is horizontally stratified with a balance between gravitational and pressure forces. When this balance is perturbed, it leads to the generation of buoyancy or “gravity” waves. An example of these is clear air turbulence, which can have dramatic effects on airplanes. As these waves propagate upward, the decrease in atmospheric density and conservation of energy combine to give …

The Noctilucent Cloud (Nlc) Display During The Ecoma/Mass Sounding Rocket Flights On 3 August 2007: Morphology On Global To Local Scales, G. Baumgarten, J. Fiedler, K. H. Fricke, M. Gerding, M. Hervig, P. Hoffmann, N. Müller, Pierre-Dominique Pautet, M. Rapp, C. Robert, D. Rusch, C. Von Savigny, W. Singer

Publications

During the ECOMA/MASS rocket campaign large scale NLC/PMC was observed by satellite, lidar and camera from polar to mid latitudes. We examine the observations from different instruments to investigate the morphology of the cloud. Satellite observations show a planetary wave 2 structure. Lidar observations from Kühlungsborn (54° N), Esrange (68° N) and ALOMAR (69° N) show a highly dynamic NLC layer. Under favorable solar illumination the cloud is also observable by ground-based cameras. The cloud was detected by cameras from Trondheim (63° N), Juliusruh (55° N) and Kühlungsborn. We investigate planetary scale morphology and local scale gravity wave structures, important …

Convection: The Likely Source Of The Medium-Scale Gravity Waves Observed In The Oh Airglow Layer Near Brasilia, Brazil, During The Spreadfex Campaign, Sharon L. Vadas, Michael J. Taylor, Pierre-Dominique Pautet, P. A. Stamus, David C. Fritts, H. L. Liu, F. T. São Sabbos, V. T. Batista, H. Takahashi, V. T. Rampinelli

Publications

Six medium-scale gravity waves (GWs) with horizontal wavelengths of λH=60–160 km were detected on four nights by Taylor et al. (2009) in the OH airglow layer near Brasilia, at 15° S, 47° W, during the Spread F Experiment (SpreadFEx) in Brazil in 2005. We reverse and forward ray trace these GWs to the tropopause and into the thermosphere using a ray trace model which includes thermospheric dissipation. We identify the convective plumes, convective clusters, and convective regions which may have generated these GWs. We find that deep convection is the highly likely source of four of these GWs. We pinpoint …

Determinants Of Atmospheric Mercury Concentrations In Reno, Nevada, U.S.A., Seth N. Lyman, Mae Sexauer Gustin

USU Uintah Basin Faculty Publications

Concentrations of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM) and particulate-bound mercury (PBM) were measured along with ancillary variables 9 km east of downtown Reno, Nevada, U.S.A. from November 2006 through March 2009. Mean two-year (February 2007 through January 2009) GEM, GOM, and PBM concentrations were 2.0 ± 0.7 ng m− 3 (± standard deviation), 18 ± 22 pg m− 3, and 7 ± 7 pg m− 3, respectively. Data collected were compared with observations made at another location just north of the city at 169 m higher elevation. At both locations higher concentrations of GEM and PBM occurred …

Observations Of Speciated Atmospheric Mercury At Three Sites In Nevada: Evidence For A Free Tropospheric Source Of Reactive Gaseous Mercury, Peter Weiss-Penzias, Mae Sexauer Gustin, Seth Lyman

USU Uintah Basin Faculty Publications

Air mercury (Hg) speciation was measured for 11 weeks (June–August 2007) at three sites simultaneously in Nevada, USA. Mean reactive gaseous Hg (RGM) concentrations were elevated at all sites relative to those reported for locations not directly influenced by known point sources. RGM concentrations at all sites displayed a regular diel pattern and were positively correlated with ozone (O₃) and negatively correlated with elemental Hg (Hg0) and dew point temperature (Tdp). Superimposed on the diel changes were 2- to 7-day periods when RGM concentrations increased across all three sites, producing significant intersite correlations of RGM daily means (r …

Modeling The Electrodynamics Of The Low-Latitude Ionosphere, Christian Stephen Wohlwend

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The electrodynamics of the Earth's low-latitude ionosphere is dependent on the ionospheric conductivity and the thermospheric neutral density, temperature, and winds present. This two-part study focused on the gravity wave seeding mechanism of equatorial plasma depletions in the ionosphere and the associated equatorial spread F, as well as the differences between a two-dimensional flux tube integrated electrodynamics model and a three-dimensional model for the same time period. The gravity wave seeding study was based on a parameterization of a gravity wave perturbation using a background empirical thermosphere and a physics-based ionosphere for the case of 12 UT on 26 September …

Usu’S Rayleigh-Scatter Lidar, Vincent B. Wickwar

Presentations

No abstract provided.

Algorithm Development For Column Water Vapor Retrieval Using The Sun And Aureole Measurement (Sam) Sensor, Joshua Bruce Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To understand and model the energetics of the Sun-Earth connection, measurements of specific atmospheric molecules are beneficial. The objective is to formulate an algorithm to derive temporally varying atmospheric water vapor concentrations as functions of altitude, latitude, and longitude from solar irradiance absorption measurements. The Visidyne SAM (Sun and Aureole Measurement) instrument, which studies the size and distribution of cloud particles, was used to obtain the experimental data. By introducing a spectrometer to the SAM instrument, column water vapor is produced as part of the data product. A new model optimized algorithm is developed and tested versus existing algorithms. Through …

Large-Amplitude Temperature Waves In The Upper Atmosphere, Jarron Lembke, Vincent B. Wickwar

Posters

Recent LIDAR research at USU found a noctilucent cloud (NLC) near the minimum of a large-amplitude temperature wave in the upper mesosphere. Such a large-amplitude wave had not been seen previously. Initial analysis suggested that this wave might be related to the diurnal tide, but greatly amplified. This research set out to learn whether these waves are a common feature. Large waves or temperature “bumps” exceeding 10 K were found in more than half the observations. A later stage will be to see if they are linked to the tides.

Speciation Of Atmospheric Mercury At Two Sites In Northern Nevada, Usa, Seth N. Lyman, Mae Sexauer Gustin

USU Uintah Basin Faculty Publications

Gaseous elemental mercury (Hg0), reactive gaseous mercury (RGM), and mercury bound to particles (Hgp) were measured during seasonal 1- or 2-week data collection campaigns at two Mercury Deposition Network sites (NV02 and NV99) in northern Nevada, USA. The sites are rural but are located in an area of diverse natural and anthropogenic mercury sources that include undisturbed and mining mercury-disturbed enriched substrates, coal-fired power plants, ore processing facilities, and industrial facilities. Concentrations of Hg0 averaged over all campaigns were 3.0±1.7 ng m−3 at NV02 and 2.5±3.1 ng m−3 at NV99, higher than has been reported for other rural sites. Hg0 …

Seasonal And Diel Variation Of Atmospheric Mercury Concentrations In The Reno (Nevada, Usa) Airshed, Jelena Stamenkovic, Seth Lyman, Mae S. Gustin

USU Uintah Basin Faculty Publications

This paper describes total gaseous mercury (TGM) concentrations measured in Reno, Nevada from 2002 to 2005. The 3-year mean and median air Hg concentrations were 2.3 and 2.1 ng m−3, respectively. Mercury concentrations exhibited seasonality, with the highest concentrations in winter, and the lowest in summer and fall. A well-defined diel pattern in TGM concentration was observed, with maximum daily concentrations observed in the morning and minimum in the afternoon. A gradual increase of TGM concentration was observed in the evening and over night. The early morning increase in TGM was likely due to activation of local surface emission sources …

The Green Beam—Lidar Investigations Of The Mesosphere, Vincent B. Wickwar

Presentations

No abstract provided.

Estimation Of Dry Deposition Of Atmospheric Mercury In Nevada By Direct And Indirect Methods, Seth N. Lyman, Mae Sexauer Gustin, Eric M. Prestbo, Frank J. Marsik

USU Uintah Basin Faculty Publications

Atmospheric models and limited measurements indicate that dry deposition of atmospheric mercury is an important process by which mercury is input to ecosystems. To begin to fill the measurement data gap, multiple methods were used simultaneously during seasonal campaigns conducted in 2005 and 2006 to estimate dry deposition of atmospheric mercury at two Mercury Deposition Network (MDN) sites in rural Nevada and in Reno, Nevada. Gaseous elemental mercury (Hg0), reactive gaseous mercury (RGM), and particulate-bound mercury (Hgp) concentrations were measured using Tekran 2537A/1130/1135 systems. These speciated measurements were combined with on-site meteorological measurements to estimate depositional fluxes of RGM and …