Atmospheric Sciences Commons^™

Ion-Cyclotron Resonance Heating Of O+ In The Topside Ionosphere And Mapping Outflows To The Magnetosphere, Anthony W. Pritchard

Doctoral Dissertations and Master's Theses

This thesis considers the heavy ion dynamics due to ion-cyclotron resonance energization processes that take place in the turbulent region of the Earth’s topside, high latitude ionosphere. We simulate the impact of this transverse heating process upon energies and velocity distribution functions of outflowing oxygen ions (O+) in the approximate altitude range of 800 km to 15,000 km. To do so most effectively, we use a single particle tracing model that precisely reproduces the small-scale wave-particle interaction of broadband extremely low frequency (BBELF) waves with the ions’ cyclotron motions, leading to the upward acceleration of ions in type-II ion outflows …

Investigation Of A Mesospheric Gravity Wave Ducting Event Using Coordinated Sodium Lidar And Mesospheric Temperature Mapper Measurements At Alomar, Norway (69°N), Katrina Bossert, David C. Fritts, Pierre-Dominique Pautet, Michael J. Taylor, Bifford P. Williams, William R. Pendleton Jr.

Publications

New measurements at the ALOMAR observatory in northern Norway (69°N, 16°E) using the Weber sodium lidar and the Advanced Mesospheric Temperature Mapper (AMTM) allow for a comprehensive investigation of a gravity wave (GW) event on 22 and 23 January 2012 and the complex and varying propagation environment in which the GW was observed. These observational techniques provide insight into the altitude ranges over which a GW may be evanescent or propagating and enable a clear distinction in specific cases. Weber sodium lidar measurements provide estimates of background temperature, wind, and stability profiles at altitudes from ~78 to 105 km. Detailed …

Wind Energy Projection For The Philippines Based On Climate Change Modeling, Angeli Silang, Sherdon Niño Uy, Julie Mae Dado, Faye Abigail T. Cruz, Gemma T. Narisma, Nathaniel Joseph C. Libatique, Gregory Tangonan

Physics Faculty Publications

To complement the existing method of wind energy assessment, this study presents wind energy projection by downscaling a regional climate model, RegCM3, which is also used in predicting rainfall and temperature changes, and using a conversion method using the Weibull distribution. A couple of papers which used long-term predicting models focused on two regions, China and the US High Plains, show a decrease of about 14% and 7%-17% respectively in wind power density due to global warming over the next century. This paper focuses on a smaller grid size of 10 km x 10 km to concentrate on a specific …

Optimized Method For Black Carbon Analysis In Ice And Snow Using The Single Particle Soot Photometer, I. A. Wendl, James A. Menking, R. Färber, M. Gysel, Susan D. Kaspari, M. J. G. Laborde, M. Schwikowski

All Faculty Scholarship for the College of the Sciences

In this study we attempt to optimize the method for measuring black carbon (BC) in snow and ice using a Single Particle Soot Photometer (SP2). Beside the previously applied ultrasonic (CETAC) and Collison-type nebulizers we introduce a jet (Apex Q) nebulizer to aerosolize the aqueous sample for SP2 analysis. Both CETAC and Apex Q require small sample volumes (a few milliliters) which makes them suitable for ice core analysis. The Apex Q shows the least size-dependent nebulizing efficiency in the BC particle diameter range of 100–1000 nm. The CETAC has the advantage that air and liquid flows can be monitored …

A Coordinated Investigation Of The Gravity Wave Breaking And The Associated Dynamical Instability By A Na Lidar And An Advanced Mesosphere Temperature Mapper Over Logan, Ut (41.7°N, 111.8°W), Xuguang Cai, Tao Yuan, Yucheng Zhao, Pierre-Dominique Pautet, Michael J. Taylor, William R. Pendleton Jr.

Publications

The impacts of gravity wave (GW) on the thermal and dynamic characteristics within the mesosphere/lower thermosphere, especially on the atmospheric instabilities, are still not fully understood. In this paper, we conduct a comprehensive and detailed investigation on one GW breaking event during a collaborative campaign between the Utah State University Na lidar and the Advanced Mesospheric Temperature Mapper (AMTM) on 9 September 2012. The AMTM provides direct evidence of the GW breaking as well as the horizontal parameters of the GWs involved, while the Na lidar's full diurnal cycle observations are utilized to uncover the roles of tide and GWs …

Seasonal And Elevational Variations Of Black Carbon And Dust In Snow And Ice In The Solu-Khumbu, Nepal And Estimated Radiative Forcings, Susan Kaspari, T. H. Painter, M. Gysel, S. M. Skiles, M. Schwikowski

All Faculty Scholarship for the College of the Sciences

Black carbon (BC) and dust deposited on snow and glacier surfaces can reduce the surface albedo, accelerate snow and ice melt, and trigger albedo feedback. Assessing BC and dust concentrations in snow and ice in the Himalaya is of interest because this region borders large BC and dust sources, and seasonal snow and glacier ice in this region are an important source of water resources. Snow and ice samples were collected from crevasse profiles and snow pits at elevations between 5400 and 6400 m a.s.l. from Mera glacier located in the Solu-Khumbu region of Nepal during spring and fall 2009, …

Assessing Effects Of Permafrost Thaw On C Fluxes Based On Multiyear Modeling Across A Permafrost Thaw Gradient At Stordalen, Sweden, Jia Deng, C Li, Steve Frolking, Y Zhang, K Backstrand, P Crill

Earth Sciences

Northern peatlands in permafrost regions contain a large amount of organic carbon (C) in the soil. Climate warming and associated permafrost degradation are expected to have significant impacts on the C balance of these ecosystems, but the magnitude is uncertain. We incorporated a permafrost model, Northern Ecosystem Soil Temperature (NEST), into a biogeochemical model, DeNitrificationDeComposition (DNDC), to model C dynamics in highlatitude peatland ecosystems. The enhanced model was applied to assess effects of permafrost thaw on C fluxes of a subarctic peatland at Stordalen, Sweden. DNDC simulated soil freeze–thaw dynamics, net ecosystem exchange of CO2 (NEE), and CH4 fluxes across …

Laboratory Evaluation Of Black Carbon Deposition Onto Snow And Transport Via Snowmelt, Larry D. Hermanson, Joshua P. Schwarz

STAR Program Research Presentations

Black carbon (BC) is an aerosol material produced by incomplete combustion of fossil fuels and biomass. BC has been shown to be the second most important anthropogenic climate warming agent after carbon dioxide due to its ability to absorb solar radiation, influence cloud behavior, and accelerate snow melt. BC in otherwise clean snow can significantly reduce its reflectivity. In order to learn about the significance of BC contamination in snow, we explored the deposition of BC onto snow and the transport of BC in snow during snowmelt. A Single Particle Soot Photometer (SP2), was used to measure the concentration and …

Verification And Analysis Of Impact-Based Tornado Warnings In The Central Region Of The National Weather Service, Holly B. Obermeier

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

Tornado warnings are one of the most critical products issued by the National Weather Service (NWS), and favorable verification statistics are desirable. The 2011 NWS statistics for traditional tornado warnings indicate that the probability of detection (POD) is 70%, while the false alarm rate (FAR) is 76%. The recent Joplin, Missouri EF5 tornado event on 22 May 2011, which resulted in massive devastation and loss of life, prompted the NWS to re-evaluate the current tornado warning format. After the Joplin, MO event, the Central Region of the NWS implemented the impact-based tornado warning (IBTW) experiment in 2013. IBTWs consist of …

Eastern Us Dryline Climatology And Synoptic-Scale Environment, Rebecca S. Duell

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

The dryline is an important focal point for convection initiation, and the subject of many studies. While the most common location for drylines is the southern Great Plains, dryline passages and subsequent severe weather outbreaks have been documented in the Mississippi River Valley and into portions of the southeastern United States. Little is known about these “eastern” drylines or how often they occur, as no climatologies or detailed studies have been published on them. This thesis presents a fifteen-year climatology (1999-2013) of eastern drylines in an effort to identify how often and where they typically occur, and to identify synoptic …

The Hard Winter Of 1880–1881: Climatological Context And Communication Via A Laura Ingalls Wilder Narrative, Barbara Boustead

School of Natural Resources: Dissertations, Theses, and Student Research

The Hard Winter of 1880-1881 was featured in the Laura Ingalls Wilder historical fiction account, The Long Winter, as well as in several town histories across the region. Both meteorological records and historical accounts indicate that the winter was particularly long, snowy, and cold. The question of how “hard” a winter is for a given location depends on the climatological context, which relies on an objective characterization of winter severity. The Accumulated Winter Season Severity Index (AWSSI) allows comparison of the winter of 1880-1881 among sites across the region, as well as in the context of the period of …

Droughtscape, Summer 2014, Kelly Smith

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

Contents

Director’s report

Outlook

Drought & climate summary

Drought impacts

International drought monitoring and planning

Visiting scholars

North American Drought Monitor Forum

New primary Dust Bowl source

New additions to online webinar archive

Community Capitals Framework Institute

Upscale Feedbacks Observed And Modeled During The Mesoscale Predictability Experiment, Joseph M. Woznicki

Open Access Theses

All modes of deep convective storms perturb their local environment on temporal and spatial scales that are larger than the storm itself. Such upscale feedbacks associated with the mesoscale convective systems (MCSs) are well known; much less is known about the feedbacks associated with supercell thunderstorms that, like MCSs, represent a highly organized convective mode. Data from the Mesoscale Predictability Experiment (MPEX), in addition to CM1 model simulations, provide the means to quantify these upscale feedbacks and determine their relative influence on the subsequent predictability of the atmosphere. The 700-500 mb lapse rate (MLR), mean-layer CAPE up to 475 mb …

Springtime Atmospheric Responses To North Atlantic Sst Anomalies In Idealized Gcm Experiments: Northern Hemisphere Circulation And North American Precipitation, Michael C. Veres

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

In this study, a series of experiments using idealized sea surface temperatures (SST), land and orography are performed to examine the interactions between the Atlantic Multidecadal Oscillation (AMO), continents and major orography. Three sets of experiments are done using an increasingly realistic surface boundary (aqua-planet, land without orography and land with orography) and run using perpetual equinox conditions. For each land surface boundary, the model is forced with a zonally symmetric SST, with additional experiments with an imposed positive or negative SST anomalies in the North Atlantic. The experiments are then compared to determine how these forcings interact and what …

Aerosol Association With Severe Weather In The Great Plains, Gabriel A. Lojero

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

Aerosols particles may serve as cloud condensation nuclei (CCN) and therefore play an important role in modulating cloud microphysics, to the point where convective storm intensity may be altered. The purpose of this study is to determine the impacts of biomass burning aerosols on convective storms over the Great Plains, especially the southern Great Plains, and to show synoptic regimes characterizing differing aerosol concentrations. A new technique to identify days with a high concentration of biomass burning aerosols was developed by using organic carbon, potassium, zinc, and bromine as the predominant tracers. An eleven-year climatology (2002-2012) for the biomass burning …

Assessing Inland Hazards Associated With Hurricanes In The U.S. Atlantic Basin, Dereka Latrese Carroll

Open Access Theses

The skill of tropical-cyclone (TC) track forecasts has steadily improved over the past decades, as has the understanding of TC risk in coastal regions. However, there is still much to be learned about the TC risk in inland regions, which is complicated by the presence of coastal evacuees, and includes hazards such as inland flash flooding and tornadoes. This was exemplified by Hurricane Ivan (2004), which spawned 118 tornadoes and produced significant rainfall amounts contributing to flooding inland. Ivan was responsible for 25 deaths in the U.S. and $18.8 billion (2004 USD) in damages. As part of a larger effort …

Aerodynamic Study Of Forces Due To Wind Velocity And Angle Of Attack On Parabolic Solar Troughs, Brian Northshield

Doctoral Dissertations and Master's Theses

Scant literature exists of the atmospheric effects on parabolic solar troughs. The technology is relatively new, so supporting studies by consequence are as well.

This study examines the effects of wind at various speeds, with various angles of attack on parabolic solar troughs. This begins by picking up on previous study, corroborating previously found data, then introduces new angles of attack. The model includes the presence of the solar tube where other studies omit.

The purpose of this study is to build a data set which is useful for structural consideration. During the course of this study, it was found …

The Life Cycle Of Instability Features Measured From The Andes Lidar Observatory Over Cerro Pachon On 24 March 2012, J. H. Hecht, K. Wan, L. J. Gelinas, David C. Fritts, R. L. Walterscheid, R. J. Rudy, A. Z. Liu, S. J. Franke, F. A. Vargas, Pierre-Dominique Pautet, Michael J. Taylor, G. R. Swenson

Publications

The Aerospace Corporation's Nightglow Imager (ANI) observes nighttime OH emission (near 1.6 μm) every 2 s over an approximate 73° field of view. ANI had previously been used to study instability features seen over Maui. Here we describe observations of instabilities seen from 5 to 8 UT on 24 March 2012 over Cerro Pachon, Chile, and compare them with previous results from Maui, with theory, and with Direct Numerical Simulations (DNS). The atmosphere had reduced stability because of the large negative temperature gradients measured by a Na lidar. Thus, regions of dynamical and convective instabilities are expected to form, depending …

Initial Measurements Of Mesospheric Gravity Waves Over Mcmurdo, Antarctica, Jonathan Pugmire, Michael J. Taylor, Yucheng Zhao, P.Dominique Pautet

Graduate Student Posters

The ANtarctic Gravity Wave Instrument Network (ANGWIN) is an NSF sponsored international program designed to develop and utilize a network of gravity wave observatories using existing and new instrumentation operated at several established research stations around the continent. The primary goal is to better understand and quantify large-scale gravity wave climatology and their effects on the upper atmosphere over Antarctica. ANGWIN currently comprises research measurements from five nations (U.S., U.K., Australia, Japan, and Brazil) at seven international stations. Utah State University’s Atmospheric Imaging Lab operates all-sky infrared and CCD imagers and an Advanced Mesospheric Temperature Mapper (AMTM) imager at several …

Midlatitude Mesospheric Temperature Anomalies During Major Ssw Events As Observed With Rayleigh-Scatter Lidar, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron

Graduate Student Posters

While the mesospheric temperature anomalies associated with Sudden Stratospheric Warmings (SSWs) have been observed extensively in the polar regions, observations of these anomalies at midlatitudes are sparse. The original Rayleigh-scatter lidar that operated at the Atmospheric Lidar Observatory (ALO; 41.7°N, 111.8°W) in the Center for Atmospheric and Space Sciences (CASS) on the campus of Utah State University (USU) collected a very dense set of temperature data for 11 years, from 1993 through 2004. The temperatures derived from these data extended over the mesosphere, from 45 to 90 km. This work focuses on the extensive Rayleigh lidar observations made during seven …