Oceanography and Atmospheric Sciences and Meteorology Commons^™

Dynamics Of Equatorial Spread F Using Ground-Based Optical And Radar Measurements, Narayan P. Chapagain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Earth's equatorial ionosphere most often shows the occurrence of large plasma density and velocity fluctuations with a broad range of scale sizes and amplitudes. These night time ionospheric irregularities in the F-region are commonly referred to as equatorial spread F (ESF) or plasma bubbles (EPBs). This dissertation focuses on analysis of ground-based optical and radar measurements to investigate the development and dynamics of ESF, which can significantly disrupt radio communication and GPS navigation systems. OI (630.0 nm) airglow image data were obtained by the Utah State University all-sky CCD camera, primarily during the equinox period, from three different longitudinal …

Multi-Scale Modeling Study Of The Source Contributions To Near-Surface Ozone And Sulfur Oxides Levels Over California During The Arctas-Carb Period, M. Huang, Gregory R. Carmichael, S N. Spak, B Adhikary, S Kulkarni, Y Cheng, C Wei, Y Tang, A D'Allura, Paul Wennberg, L Gregory Huey, Jack E. Dibb, Jose L. Jimenez, Michael J. Cubison, Andrew Weinheimer, Ajith P. Kaduwela, Chenxia Cai, M Wong, R Bradley Pierce, J Al-Saadi, David G. Streets, Q Zhang

Earth Sciences

Chronic high surface ozone (O₃) levels and the increasing sulfur oxides (SO_x = SO₂+SO₄) ambient concentrations over South Coast (SC) and other areas of California (CA) are affected by both local emissions and long-range transport. In this paper, multi-scale tracer, full-chemistry and adjoint simulations using the STEM atmospheric chemistry model are conducted to assess the contribution of local emission sourcesto SC O₃ and to evaluate the impacts of transported sulfur and local emissions on the SC sulfur budgetduring the ARCTAS-CARB experiment period in 2008. Sensitivity simulations quantify contributions of biogenic and fire …

Droughtscape, Spring 2011, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

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Forecasters Say Dryness in TX and SW to Continue

Drought Planning, The Game: Coming Soon

Ding Takes New Post

South and Southwest Lose Crops, Fight Fires

Drought Monitor Authors Review Enhanced GIS Tools and New Processes

Evaluation Of The Sensitivity Of Inventory And Monitoring National Parks To Acidification Effects From Atmospheric Sulfur And Nitrogen Deposition, Northern Great Plains Network (Ngpn), T. J. Sullivan, T. C. Mcdonnell, G. T. Mcpherson, S. D. Mackey, D. Moore

United States National Park Service: Publications

Northern Great Plains Network (NGPN)

National maps of atmospheric sulfur (S) and nitrogen (N) emissions and deposition are provided in Maps A through D as context for subsequent network data presentations. Maps A and B show county level emissions of total S and total N for the year 2002. Maps C and D show total S and total N deposition, again for the year 2002.

There are three parks in the Northern Great Plains Network that are larger than 100 square miles: Badlands (BADL), Missouri (MNRR), and Theodore Roosevelt (THRO). In addition, there are 10 smaller parks.

Total annual S …

Design And Demonstration Of A Miniature Lidar System For Rover Applications, Benjamin Robinson

Electrical & Computer Engineering Theses & Dissertations

Public awareness of harmful human environmental effects such as global warming has increased greatly in recent years and researchers have increased their efforts in gaining more knowledge about the Earth's atmosphere. Natural and man-made processes pose threats lo the environment and human life, so knowledge of all atmospheric processes is necessary. Ozone and aerosols are important factors in many atmospheric processes and active remote sensing techniques provide a way lo analyze their quantity and distribution.

A compact ground-based lidar system for a robotic platform meant for atmospheric aerosol measurements was designed, tested, and evaluated. The system will eventually be deployed …

Analysis Of Plasma Bubble Signatures In The Ionosphere, Omar A. Nava

Theses and Dissertations

Plasma bubbles are large scale structures of depleted plasma density in Earth's ionosphere that disrupt radio and satellite communications, to include global navigation satellite systems. This study used the Ionospheric Forecast Model (IFM) to analyze affected look angles and total electron content (TEC) differences due to plasma bubbles of various sizes for 27 geophysical conditions consisting of different seasons and levels of solar and geomagnetic activity at 421 GPS ground stations worldwide. Overall, different geographic locations and plasma bubble configurations produced different affected look angle profiles. Bigger plasma bubbles, larger density depletion factors, higher levels of solar activity and the …

Passive Ranging Of Dynamic Rocket Plumes Using Infrared And Visible Oxygen Attenuation, Robert Anthony Vincent

Theses and Dissertations

Atmospheric oxygen absorption bands in observed spectra of boost phase missiles can be used to accurately estimate range from sensor to target. This work compares two oxygen absorption bands in the near-infrared (NIR) and visible (Vis) spectrum, centered at 762nm and 690 nm, to passively determine range. Spectra were observed from static tests of both surface-to-air missile simulators at 405m range and a full-scale solid rocket motor at 900m range. The NIR O₂ band provided range estimates accurate to within 3% for both tests, while the Vis O₂ band had range errors of 77% and 15 %, respectively. …

Trends Of Wind And Wind Power Over The Coterminous United States, Eric M. Holt

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The trends of wind and wind power at a typical wind turbine hub height (80 m) are analyzed using the North American Regional Reanalysis (NARR) dataset for 1979-2009. Based upon the wind speeds at NARR’s vertical layers right above and below the 80 m level, the wind speeds at 80 m are estimated using two methods assuming the wind profile respectively as linear and power-law distribution with respect to the altitude in the lower boundary layer. Furthermore, we calculate the following variables at 80 m that are needed for the estimation and interpretation of wind power: the air density, zonal …

The Effect Of Zonally Asymmetric Ozone Heating On The Northern Hemisphere Winter Polar Stratosphere, J. P. Mccormack, T. R. Nathan, E. C. Cordero

Faculty Publications, Meteorology and Climate Science

[1] Previous modeling studies have found significant differences in winter extratropical stratospheric temperatures depending on the presence or absence of zonally asymmetric ozone heating (ZAOH), yet the physical mechanism causing these differences has not been fully explained. The present study describes the effect of ZAOH on the dynamics of the Northern Hemisphere extratropical stratosphere using an ensemble of free-running atmospheric general circulation model simulations over the 1 December - 31 March period. We find that the simulations including ZAOH produce a significantly warmer and weaker stratospheric polar vortex in mid-February due to more frequent major stratospheric sudden warmings compared to …

Evaluation Of The Sensitivity Of Inventory And Monitoring National Parks To Nutrient Enrichment Effects From Atmospheric Nitrogen Deposition Northern Great Plains Network (Ngpn), T. J. Sullivan, T. C. Mcdonnell, G. T. Mcpherson, S. D. Mackey, D. Moore

United States National Park Service: Publications

Northern Great Plains Network (NGPN)

National maps of atmospheric N emissions and deposition are provided in Maps A and B as context for subsequent network data presentations. Map A shows county level emissions of total N for the year 2002. Map B shows total N deposition, again for the year 2002.

There are three parks in the Northern Great Plains Network that are larger than 100 square miles: Badlands (BADL), Missouri (MNRR), and Theodore Roosevelt (THRO). In addition, there are 10 other smaller parks.

Total annual N emissions, by county, are shown in Map C for lands in and surrounding …

Incoherent Scatter Radar Estimation Of F Region Ionospheric Composition During Frictional Heating Events, M. Zettergren, J. L. Semeter, C. Heinselman, M. Diaz

Publications

A method is developed for estimating F region ion composition from incoherent scatter radar (ISR) measurements during times of frictional ion heating. The technique addresses ion temperature‐mass ambiguities in the IS spectra by self‐consistently modeling ion temperature profiles, including the effects of ion temperature anisotropies and altitude‐independent neutral winds. The modeled temperature profiles are used in a minimization procedure to estimate ion composition consistent with the recorded IS spectra. The proposed method is applicable to short‐integration (min) data sets from either single‐beam or multiple‐beam experiments. Application of the technique to Sondrestrom ISR measurements shows increases in F region molecular ions …

Fire Whirl Evolution Observed During A Valley Wind-Sea Breeze Reversal, Daisuke Seto, Craig B. Clements

Faculty Publications, Meteorology and Climate Science

This observational study documented the atmospheric environment of a prescribed fire conducted in a narrow valley when a small fire whirl developed during a mesoscale wind reversal. Based on analysis of in situ meteorological measurements, it is hypothesized that the fire whirl formed due to the presence of strong vertical wind shear caused by the interaction of a sea breeze front with a weaker up-valley wind. Vorticity generated by the interaction of the wind shear and the fire front was estimated to be ~0.2 s−1. Peak turbulence kinetic energy was caused by the wind shear rather than the buoyancy generated …

Droughtscape, Winter 2011, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Register for the U.S. Drought Monitor Forum

La Niña Brings Southeast, Southwest Drought

International Efforts

Drought Returns in 2010

Impacts Emerge “Before” Summer Drought in East

October-December Quarterly Impacts Summary

Climate Adaptation for Local Government

NDMC Elicits Missouri River Basin Recollections

Woudenberg Coordinates Educational Booklet

Influence Of Karst Landscape On Planetary Boundary Layer Atmosphere: A Weather Research And Forecasting (Wrf) Model–Based Investigation, Ronnie Leeper, Rezaul Mamood, Arturo I. Quintanar

High Plains Regional Climate Center: Staff Publications

Karst hydrology provides a unique set of surface and subsurface hydrological components that affect soil moisture variability. Over karst topography, surface moisture moves rapidly below ground via sink holes, vertical shafts, and sinking streams, reducing surface runoff and moisture infiltration into the soil. In addition, subsurface cave blockage or rapid snowmelt over karst can lead to surface flooding. Moreover, regions dominated by karst may exhibit either drier or wetter soils when compared to nonkarst landscape. However, because of the lack of both observational soil moisture datasets to initialize simulations and regional land surface models (LSMs) that include explicit karst hydrological …

Tropical-Extratropical Interactions And Arctic-Extratropical Interactions Conducive To Intraseasonal Variability Of The North Pacific Jet Stream, Jason Michael Cordeira

Legacy Theses & Dissertations (2009 - 2024)

The autumnal spin up of the Northern Hemisphere (NH) general circulation is characterized by intraseasonal variability in the structure of the North Pacific jet stream (NPJ). The variability in the structure of the NPJ is often associated with large-scale flow reconfigurations over the North Pacific and North America and changes in the NH zonal available potential energy (AZ). This dissertation investigates variability in the structure of the NPJ and the NH AZ in conjunction with tropical-extratropical interactions (TEIs) and arctic-extratropical interactions (AEIs). The former are investigated in association with the El Niño-Southern Oscillation, the Madden-Julian Oscillation, and western North Pacific …

Review Of The Simulation Of The Precis Regional Climate Model Over Tropical South America Using Gcm And Reanalysis Lateral Boundary Conditions, Dana Mcglone

Legacy Theses & Dissertations (2009 - 2024)

High-resolution regional climate models (RCM) run over a limited domain are increasingly used to simulate seasonal to interannual climate variability over South America and to assess the spatiotemporal impact of future climate change under a variety of emission scenarios. Global climate models (GCM) are often too coarse to resolve local circulations and the topography of the Andes, leading to problems with simulation of temperature and precipitation patterns throughout the domain. A RCM model can also better represent the climate at a regional scale; however, they are subject to errors introduced by the driving global models. For this study, the Hadley …

Significance Of Hno3 Acid Photolysis On Surfaces In Tropospheric Chemistry, Honglian Gao

Legacy Theses & Dissertations (2009 - 2024)

The reactive nitrogen trace gases (NO_y) including nitrogen oxides (NO_x) and their secondary products are known to cause ground-level ozone pollution, photochemical smog, acid deposition, and overall air quality degradation. NO_x was believed to be permanently removed from the atmospheric by HNO₃ formation and deposition. However, our laboratory experimental results show that HNO₃ can be remobilized back to photochemically labile HONO and NO_x (re-NOx-ification). We have verified and quantified HONO and NO_x production from the photolysis of HNO₃ on various surfaces, including Pyrex, leaves of plants, and other environmentally relevant …

Easterly Waves And Tropical Cyclogenesis In The Caribbean, Kay Louise Shelton

Legacy Theses & Dissertations (2009 - 2024)

This thesis is concerned with the evolution of easterly waves in the Atlantic and Caribbean and their relationship to tropical cyclogenesis. Motivation for this study is the apparent "genesis hole" in the eastern Caribbean and the lack of knowledge regarding the evolution of the transient disturbances passing through this region. The environment of the Caribbean is reviewed revealing large vertical wind shear and dry mid-levels as the key factors determining the presence of the genesis hole.

The Influence Of The Great Lakes On Mcs Formation And Development In The Warm Season, Alan Frederick Srock

Legacy Theses & Dissertations (2009 - 2024)

This study focuses on how near-surface thermal boundaries that form near the Great Lakes during the warm season can contribute to the formation of mesoscale convective systems (MCSs). Differential heating across land-water interfaces can create a cold dome of air over the lake; convection may develop when the relatively-cold dome of air becomes deep enough to enable air parcels that intersect these boundaries to reach their level of free convection. A radar-based climatology of MCS events surrounding the Great Lakes for 2002-2005 showed that MCSs frequently form in the vicinity of the Great Lakes. Composites of MCS events over the …

Northeast United States Heat Waves : A Statistical Analysis And Synoptic Climatology, Scott Cooper Runyon

Legacy Theses & Dissertations (2009 - 2024)

The results of a statistical analysis of anomalously hot day and heat wave frequency in the United States (U.S.) are presented, along with a synoptic climatology of northeast U.S. heat waves (NHWs) for 1948-2001. This study used daily high temperatures retrieved from the National Climatic Data Center (NCDC) Daily Surface Dataset for 54 stations binned into the nine standard NCDC climate regions. Anomalously hot days were defined as when the daily high temperature exceeded the climatological 97.5-percentile temperature. Heat waves were defined as at least three consecutive anomalously hot days, whereas regional heat waves (e.g., NHWs) were defined as simultaneous …

The Downstream Extratropical Flow Response To Recurving Western North Pacific Tropical Cyclones, Heather M. Archambault

Legacy Theses & Dissertations (2009 - 2024)

The factors that govern the downstream flow response to recurving western North Pacific (WNP) tropical cyclones (TCs) are investigated from climatological, composite analysis, case study, and predictability perspectives. A 1979–2009 climatology of WNP TC recurvature indicates that TC recurvature is followed by a four-day period of above-normal North Pacific meridional flow. The relationship between TC recurvature and above-normal North Pacific meridional flow is found to be stronger in late summer through mid-fall than in early summer and early winter, and stronger for TCs that interact strongly with the jet stream than for TCs that interact weakly with the jet stream. …

Origin And Maintenance Of The Stable Boundary Layer In A Patchy Landscape, Luiz Eduardo Medeiros

Legacy Theses & Dissertations (2009 - 2024)

Field observations made in Hudson Valley region, NY during the Hudson Valley Ambient Meteorology Study (HVAMS) are analyzed to examine how terrain and land cover influence nocturnal mixing in real-world landscapes. Important terrain features such as local topographic concavity and site sheltering are shown to exhibit systematic influence on turbulent intermittency and on the consequent nocturnal heat and momentum fluxes. Very local obstacles have their most important effects on mixing during strong winds (> 5m/s). Local terrain concavity was found to be the more important factor influencing surface fluxes than sheltering for all classes of winds.

Persistence And Dissipation Of Lake Michigan-Crossing Mesoscale Convective Systems, Nicholas Metz

Legacy Theses & Dissertations (2009 - 2024)

This thesis investigates mature mesoscale convective systems (MCSs) that traversed Lake Michigan to elucidate synoptic-scale and Lake Michigan-related features that discriminate between persistence and dissipation. Of the 110 coherent MCSs that crossed Lake Michigan during the warm seasons (April–September) of 2002–2007, 47 (43%) persisted, while 63 (57%) dissipated. Persistence was favored during July and August, when Lake Michigan was warmer and during the evening and overnight, when the low-level jet (LLJ) was most intense. However, a number of MCSs also persisted during the early warm season when the Lake Michigan water temperature was cooler than the surrounding land.

Improving Simulations Of The Upper Ocean By Inclusion Of Surface Waves In The Mellor-Yamada Turbulence Scheme, Chuan Jiang Huang, Fangli Qiao, Zhenya Song, Tal Ezer

CCPO Publications

The Mellor-Yamada turbulence closure scheme, used in many ocean circulation models, is often blamed for overly high simulated surface temperature and overly low simulated subsurface temperature in summer due to insufficient vertical mixing. Surface waves can enhance turbulence kinetic energy and mixing of the upper ocean via wave breaking and nonbreaking-wave-turbulence interaction. The influences of wave breaking and wave-turbulence interaction on the Mellor-Yamada scheme and upper ocean thermal structure are examined and compared with each other using one-dimensional and three-dimensional ocean circulation models. Model results show that the wave-turbulence interaction can effectively amend the problem of insufficient mixing in the …

The Integrated Wrf/Urban Modeling System: Development, Evaluation, And Applications To Urban Environmental Problems, Fei Chen, Hiroyuki Kusaka, Robert Bornstein, Jason Ching, C.S.B. Grimmond, Susanne Grossman-Clarke, Thomas Loridan, Kevin W. Manning, Alberto Martilli, Shiguang Miao, David J. Sailor, Francisco P. Salamanca, Haider Taha, Mukul Tewari, Xuemei Wang, Andrzej A. Wyszogrodzki, Chaolin Zhang

Mechanical and Materials Engineering Faculty Publications and Presentations

To bridge the gaps between traditional mesoscale modeling and microscale modeling, the National Center for Atmospheric Research (NCAR), in collaboration with other agencies and research groups, has developed an integrated urban modeling system coupled to the Weather Research and Forecasting (WRF) model as a community tool to address urban environmental issues. The core of this WRF/urban modeling system consists of: 1) three methods with different degrees of freedom to parameterize urban surface processes, ranging from a simple bulk parameterization to a sophisticated multi-layer urban canopy model with an indoor outdoor exchange sub-model that directly interacts with the atmospheric boundary layer, …

Fossil And Contemporary Aerosol Particulate Organic Carbon In The Eastern United States: Implications For Deposition And Inputs To Watersheds, Andrew S. Wozniak, James E. Bauer, Rebecca M. Dickhut

Chemistry & Biochemistry Faculty Publications

Atmospheric particulate matter samples were collected from mid-Atlantic and northeastern U. S. (Virginia and New York, respectively) sites to assess the fossil versus contemporary sources contributing to aerosol organic carbon (OC) and the implications for its deposition to watersheds. Mean particulate matter total OC (TOC) deposition rates (wet + dry deposition) were calculated to be 1.6 and 2.4 mg C m^-2 d^-1 for the Virginia and New York sites, respectively. Wet deposition of particulate TOC was determined to be the dominant depositional mode, accounting for >65% (Virginia) and >80% (New York) of total aerosol TOC deposition. Isotopic mass …

Ace-Fts Measurements Of Trace Species In The Characterization Of Biomass Burning Plumes, K. A. Tereszchuk, G. González Abad, C. Clerbaux, D. Hurtmans, P.-F. Coheur, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

To further our understanding of the effects of biomass burning emissions on atmospheric composition, we report measurements of trace species in biomass burning plumes made by the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) instrument on the SCISAT-1 satellite. An extensive set of 15 molecules, C₂H₂, C₂H₆, CH₃OH, CH₄, CO, H₂CO, HCN, HCOOH, HNO₃, NO, NO₂, N₂O₅, O-3, OCS and SF₆ are used in our analysis. Even though most biomass burning smoke is typically confined to the …

Aerosol Characterizaton In El Paso-Juarez Airshed Using Optical Methods, Angel E. Esparza

Open Access Theses & Dissertations

The assessment and characterization of atmospheric aerosols and their optical properties are of great significance for several applications such as air pollution studies, atmospheric visibility, remote sensing of the atmosphere, and impacts on climate change. Decades ago, the interest in atmospheric aerosols was primarily for visibility impairment problems; however, recently interest has intensified with efforts to quantify the optical properties of aerosols, especially because of the uncertainties surrounding the role of aerosols in climate change. The main objective of the optical characterization of aerosols is to understand their properties. These properties are determined by the aerosols' chemical composition, size, shape …

Balloon Borne Mars Research Platforms, Sean Michael Hancock

Mechanical & Aerospace Engineering Theses & Dissertations

Aerial platforms can fill a measurement gap between orbiters and rovers, providing planetary scale high resolution in situ measurements, access to scientifically interesting terrain that is either inaccessible or hazardous to rovers, and serve as a planet-wide delivery platforms to deploy surface probes and rovers to areas inaccessible given existing entry, descent, and landing systems. A permanent robotic outpost on the Martian surface can utilize locally-derived hydrogen as a lifting gas for balloon systems deployed from Mars. That approach can simplify the inflation and launch of aerial vehicles while allowing for a long duration deployment campaign that is not constrained …

A Third-Order Non-Oscillatory Finite-Volume Transport Scheme For Atmospheric Modeling, Kiran Kumar Katta

Open Access Theses & Dissertations

Atmospheric numerical modeling has been going through drastic changes over the past decade, mainly to utilize the massive computing capability of the petascale systems. This obliges the modelers to develop grid systems and numerical algorithms that facilitate exceptional level of scalability on these systems. The numerical algorithms that can address these challenges should have the local properties such as the high on-processor operation count and minimum parallel communication i.e. high parallel efficiency, it should also satisfy the following properties such as inherent local and global conservation, high-order accuracy, geometric flexibility, non-oscillatory advection, positivity preservation.

In the present work, A Third-order …