Atmospheric Sciences Commons^™

Parameterizing Wave‐Driven Vertical Constituent Transport In The Upper Atmosphere, Alan Z. Liu, Chester S. Gardner, Yafang Guo

Publications

Dissipating waves contribute to vertical mixing of the atmosphere, alter molecular and eddy diffusion, and induce chemical transport of reactive species. These processes induce strong vertical transport of atmospheric constituents in regions where wave dissipation is significant. The effective wave diffusivity is proportional to the Stokes drift velocity imparted by the spectrum of vertically propagating waves, which is related to the vertical heat and wave energy fluxes. Because the heat flux cannot be derived from wave parameterization schemes employed in most atmospheric models, wave‐driven constituent transport has not been fully incorporated. However, we show in this paper that wave diffusivity …

Umphlett Qci June 2019, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Soil Moisture Conditions

Delayed/Prevented Planting

Impacts to Cattle

Damage to Infrastructure

Temperature

Precipitation

Power-Law Scaling In The Internal Variability Of Cumulus Cloud Size Distributions Due To Subsampling And Spatial Organization, R. A. J. Neggers, P. J. Griewank, Thijs Heus

Physics Faculty Publications

In this study, the spatial structure of cumulus cloud populations is investigated using three-dimensional snapshots from large-domain LES experiments. The aim is to understand and quantify the internal variability in cloud size distributions due to subsampling effects and spatial organization. A set of idealized shallow cumulus cases is selected with varying degrees of spatial organization, including a slowly organizing marine precipitating case and five more quickly organizing diurnal cases over land. A subdomain analysis is applied, yielding cloud number distributions at sample sizes ranging from severely undersampled to nearly complete. A strong power-law scaling is found in the relation between …

Microcontroller Differential Gps To Subtract Signal Delay Due To Ambient Free Electrons In The Ionosphere, Diana Jane Swanson

Physics

The goal of this project is to create a Global Positioning System (GPS) receiver that is more precise than one GPS receiver on its own. The technique is to take the difference between a GPS receiver’s measured position and its actual position, then use radio frequency (RF) communication to send that differential value to another microcontroller GPS receiver. This differential value will be added to the measured second location to get a more accurate position for the second GPS receiver, thus creating a differential GPS.

Tdim Ionospheric Model Tec Maps Of The High-Latitude Northern Hemisphere, Used In The Paper Titled "Hemispherical Shifted Symmetry In Polar Cap F-Region Patch Occurrence: A Survey Of Gps Tec Data From 2015 To 2018", Michael David, Jan J. Sojka

Browse all Datasets

TDIM ionospheric model was run for the year 2018 at 10-day intervals and 2-hr intervals in UT.

Effects Of The Hall Conductivity In Ionospheric Heating Experiments, B. Tulegenov, A. V. Streltsov

Publications

We investigate the role of Hall conductivity in ionospheric heating experiments. Ionosphericheating by powerful X-mode waves changes the Hall and Pedersen conductances in theEandDregions,which lead to the generation of ultra-low frequency (ULF)/extremely-low frequency/very low frequencywaves, when the electric field exists in the ionosphere. The importance of the Hall currents in themagnetosphere-ionosphere interactions, carried by ULF waves and field-aligned currents, has beenconsistently overlooked in studies devoted tothe active experiments. Simulations of the three-dimensionaltwo-fluid magnetohydrodynamic (MHD) model, presented in this paper, demonstrate that the Hallconductivity changes (1) the growth rate and the amplitude of ULF waves generated by the heating and (2)the …

Land – Atmosphere – Meteorological Coupling Associated With The 2015 Gorkha (M 7.8) And Dolakha (M 7.3) Nepal Earthquakes, Feng Jing, Ramesh P. Singh, Xuhui Shen

Mathematics, Physics, and Computer Science Faculty Articles and Research

Multiple parameters (brightness temperature, soil moisture, surface latent heat flux, surface air temperature and carbon monoxide) before and after the 2015 Nepal M7.8 Gorkha main earthquake and M7.3 Dolakha aftershock were analysed using satellite observation data. The thermal anomalies from optical and microwave data appear about two months prior to the 2015 Gorkha earthquake. Some of the parameters show anomalous changes at different altitudes about 20 days prior to the main earthquake event and 10 days prior to the strong aftershock. Our results show that pre-earthquake anomalous signals propagate from the in situ to the top of atmosphere, and the …

Intercomparison Of Small Unmanned Aircraft System (Suas) Measurements For Atmospheric Science During The Lapse-Rate Campaign, Lindsay Barbieri, Stephan T. Kral, Sean C. C. Bailey, Amy E. Frazier, Jamey D. Jacob, Joachim Reuder, David Brus, Phillip B. Chilson, Christopher Crick, Carrick Detweiler, Abhiram Doddi, Jack Elston, Hosein Foroutan, Javier González-Rocha, Brian R. Greene, Marcelo I. Guzman, Adam L. Houston, Ashraful Islam, Osku Kemppinen, Dale Lawrence, Elizabeth A. Pillar-Little, Shane D. Ross, Michael P. Sama, David G. Schmale Iii, Travis J. Schuyler, Ajay Shankar, Suzanne W. Smith, Sean Waugh, Cory Dixon, Steve Borenstein, Gijs De Boer

Chemistry Faculty Publications

Small unmanned aircraft systems (sUAS) are rapidly transforming atmospheric research. With the advancement of the development and application of these systems, improving knowledge of best practices for accurate measurement is critical for achieving scientific goals. We present results from an intercomparison of atmospheric measurement data from the Lower Atmospheric Process Studies at Elevation—a Remotely piloted Aircraft Team Experiment (LAPSE-RATE) field campaign. We evaluate a total of 38 individual sUAS with 23 unique sensor and platform configurations using a meteorological tower for reference measurements. We assess precision, bias, and time response of sUAS measurements of temperature, humidity, pressure, wind speed, and …

Antecedent North Pacific Jet Regimes Conducive To The Development Of Cool Season Continental U.S. Tornado Outbreaks, Jessica Blair

Atmospheric & Environmental Sciences

The occurrence of tornado outbreaks are often associated with considerable societal and economic impacts. The U.S. averages nearly 1000 tornadoes per year that result in 1500 injuries and 80 fatalities, many of which are associated with outbreak days. Additionally, one outbreak alone can cause millions of dollars in property damage. The location of these outbreaks can vary temporally throughout the cool season (September–May) and can vary substantially in terms of their severity.

This study focuses on continental U.S. tornado outbreaks during the cool season and their relation to the state and evolution of the North Pacific jet (NPJ) stream 0–5 …

Daily To Seasonal Moisture Signals Present In Sub-Annual Tree-Ring Data, Ian Howard

Graduate Theses and Dissertations

In recent decades, there has been an increase in the development of sub-annual earlywood (EW) and latewood (LW) width tree-ring chronologies that have been used to make long-term inferences about discrete seasonal moisture variability for different regions of North America. This doctoral research developed a new network of EW, LW, and adjusted latewood (LWa) tree-ring chronologies from the western Great Plains. These chronologies were used to reconstruct 300+ years of spring and summer moisture variability over the northern and southern Plains. The reconstructions document new information about the long-term seasonal climate history of the Great Plains, including the unusual nature …

Cool And Warm Season Climate Signals In Tree Rings From North America, Max Carl Arne Torbenson

Graduate Theses and Dissertations

Earlywood (EW) and latewood (LW) ring-width chronologies have become an increasingly important proxy in paleoclimate reconstructions. These subannual variables can provide estimates of past hydroclimate variability for seasonal windows that total ring-widths cannot resolve. The strength of the relationship between EW and LW series may influence what type of paleoclimate information is embedded within the tree-ring series. High correlations (> 0.70) between EW and LW are recorded for much of the continent but the magnitude of correlation varies greatly across space and species boundaries. Using four LW chronologies from shortleaf pine, the North American conifer species displaying the lowest EW-LW …

On The Long Lasting “C‐Type” Structures In The Sodium Lidargram: The Lifetime Of Kelvin‐Helmholtz Billows In The Mesosphere And Lower Thermosphere Region, S. Mondal, S. Sarkhel, Jay Agarwal, D. Chakrabarty, R. Sekar, Tao Yuan, Alan Z. Liu, Et Al.

Publications

In order to understand the characteristics of long‐lasting “C‐type” structure in the Sodium (Na) lidargram, six cases from different observational locations have been analyzed. The Na lidargram, collected from low‐, middle‐, and high‐latitude sites, show long lifetime of the C‐type structures which is believed to be the manifestation of Kelvin‐Helmholtz (KH) billows in the Mesosphere and Lower Thermosphere (MLT) region. In order to explore the characteristics of the long‐lasting C‐type structures, the altitude profile of square of Brunt‐Väisälä frequency in the MLT region has been derived using the temperature profile collected from the Na lidar instruments and the SABER instrument …

Artificial Aurora Produced By Haarp, B. Tulegenov, A. V. Streltsov, E. Kendall, M. Mccarrick, I. Galkin

Publications

We present results from the ionospheric heating experiment conducted at the HighFrequency Active Auroral Research Program (HAARP) facility, Alaska, on 12 March 2013. During theexperiment, HAARP transmitted in the direction of the magnetic zenith X-mode 4.57-MHz wave. Thetransmitted power was modulated with the frequency of 0.9 mHz, and it was pointed on a 20-km spot at thealtitude of 120 km. The heating (1) generates disturbances in the magnetic field detected with the fluxgatemagnetometer on the ground and (2) produces bright luminous spots in the ionosphere, observed with theHAARP telescope. Numerical simulations of the 3-D reduced magnetohydrodynamic (MHD) model revealthat these …

Using A Balloon-Launched Unmanned Glider To Validate Real-Time Wrf Modeling, Travis J. Schuyler, S. M. Iman Gohari, Gary Pundsack, Donald Berchoff, Marcelo I. Guzman

Chemistry Faculty Publications

The use of small unmanned aerial systems (sUAS) for meteorological measurements has expanded significantly in recent years. SUAS are efficient platforms for collecting data with high resolution in both space and time, providing opportunities for enhanced atmospheric sampling. Furthermore, advances in mesoscale weather research and forecasting (WRF) modeling and graphical processing unit (GPU) computing have enabled high resolution weather modeling. In this manuscript, a balloon-launched unmanned glider, complete with a suite of sensors to measure atmospheric temperature, pressure, and relative humidity, is deployed for validation of real-time weather models. This work demonstrates the usefulness of sUAS for validating and improving …

Gravity Wave Ducting Observed In The Mesosphere Over Jicamarca, Peru, Gerald A. Lehmacher, Christopher J. Heale, Jonathan B. Snively, Erhan Kudeki, Pablo M. Reyes, Kiwook Lee

Publications

Short-period gravity waves are ubiquitous in the mesosphere, but the vertical structures of their perturbations are difficult to observe. The Jicamarca 50-MHz very high frequency radar allows observations of winds and turbulent scatter with high temporal and vertical resolution. We present a case of a quasi-monochromatic gravity wave with period 520 (±40) s that is likely ducted below a southward wind jet between 68 and 74 km. Above this layer of evanescence, a northward wind enables it to emerge into a more stable layer, where it is refracted to a short vertical wavelength of 2.2 (±0.2) km; data show evidence …

Numerical Modeling Of The Propagation Of Infrasonic Acoustic Waves Through The Turbulent Field Generated By The Breaking Of Mountain Gravity Waves, Michael P. Hickey, Jonathan Snively, C Bailly, J. L. Garrison

Publications

The nonlinear propagation of low-frequency acoustic waves through the turbulent fluctuations induced by breaking mountain gravity waves is investigated via 2-D numerical simulations of the Navier-Stokes equations, to understand the effects of atmospheric dynamics on ground-based infrasound measurements. Emphasis is placed on acoustic signals of frequency around 0.1 Hz, traveling through tens-of-kilometers-scale gravity waves and subkilometer-scale turbulence. The sensitivity of the infrasonic phases to small-scale fluctuations is found to depend on the altitudes through which they are refracted toward the Earth. For the considered cases, the dynamics in the stratosphere impact the refracting acoustic waves to a greater extent than …

Tropospheric And Ionospheric Anomalies Induced By Volcanic And Saharan Dust Events As Part Of Geosphere Interaction Phenomena, Valerio Tramutoli, Francesco Marchese, Alfredo Falconieri, Carolina Filizzola, Nicola Genzano, Katsumi Hattori, Mariano Lisi, Jann-Yenq Liu, Dimitar Ouzounov, Michel Parrot, Nicola Pergola, Sergey Pulinets

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this work, we assessed the possible relation of ionospheric perturbations observed by Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions (DEMETER), Global Positioning System total electron content (GPS TEC), National Oceanic and Atmospheric Administration (NOAA)-derived outgoing longwave-Earth radiation (OLR), and atmospheric chemical potential (ACP) measurements, with volcanic and Saharan dust events identified by ground and satellite-based medium infrared/thermal infrared (MIR/TIR) observations. The results indicated that the Mt. Etna (Italy) volcanic activity of 2006 was probably responsible for the ionospheric perturbations revealed by DEMETER on 4 November and 6 December and by GPS TEC observations on 4 November and 12 …

Analysis Of 2017 Multi-Agency Field Campaign Data For Wintertime Surface Pollution In The Cache Valley Of Utah, Gerardo Diaz Jr.

Masters Theses & Specialist Projects

Atmospheric motions resulting from rising airborne parcels help to scatter emissions, including PM, away from their sources, decreasing local pollution levels. However this pattern shifts during the wintertime, as cold air damming and inversion layers create stable conditions that limit the vertical transport of air masses. Both point and area sources of emissions currently dot the western United States and are responsible for the production of the vast majority of agricultural pollution in the region. At the same time, population-growth has resulted in an ever-increasing amount of urbansource emissions. The entrapment of PM, which are produced when a wide array …

Contrasting Local And Long-Range-Transported Warm Ice-Nucleating Particles During An Atmospheric River In Coastal California, Usa, Andrew C. Martin, Gavin Cornwell, Charlotte M. Beall, Forest Cannon, Sean Reilly, Bas Schapp, Dolan Lucero, Jessie Creamean, F. Martin Ralph, Hari T. Mix, Kimberly Prather

Geography Faculty Publications and Presentations

Ice-nucleating particles (INPs) have been found to influence the amount, phase and efficiency of precipitation from winter storms, including atmospheric rivers. Warm INPs, those that initiate freezing at temperatures warmer than −10ºC, are thought to be particularly impactful because they can create primary ice in mixed-phase clouds, enhancing precipitation efficiency. The dominant sources of warm INPs during atmospheric rivers, the role of meteorology in modulating transport and injection of warm INPs into atmospheric river clouds, and the impact of warm INPs on mixed-phase cloud properties are not well-understood. In this case study, time-resolved precipitation samples were collected during an atmospheric …

Daily And Seasonal Variability Of Offshore Wind Power On The Central California Coast And Statewide Demand, Matthew Douglas Kehrli

Physics

No abstract provided.

Droughtscape, Spring 2019, Cory Matteson

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

Contents

From the Director

Wet and cool conditions bring drought relief to the West

Notable numbers from Q1

Drought impact summary, 1st quarter 2019

New research examines drought effects on state recreation areas

At Ethiopian space science workshop, NDMC climatologist sees promise in preparing for drought

U.S.- affiliated Pacific Islands now part of U.S. Drought Monitor

Water conservation tips for drought, flood and other disasters

Upcoming events

Blue Sky Olympics: Satellite Observations Of Air Quality During The 2008 Beijing Olympics, Lincoln M. Butcher

Student Publications

China has imposed short-term emission control regulations on industry and transportation to quickly improve air quality during certain events, including the 2008 Summer Olympic Games. Previous research noted reductions in NO2 vertical column density, CO emissions, CO2 emissions, and Aerosol Optical Depth (AOD). NO2 and SO2 decreased in neighboring provinces, during this time period. Using MODIS level-2 atmospheric aerosol product (MYD04_L2) data, processed by the dark target algorithm, this study observes trends in regional AOD and temporal change in AOD during the Olympic emissions reduction program. 2008 observations are referenced against AOD observations from 2003 to 2013, within 9-day intervals …

Planar Ion Probe For Low-Latitude Ionosphere/Thermosphere Enhancements In Density Cubesat Mission, Liam Owen Gunter

Doctoral Dissertations and Master's Theses

One of the crucial measurements for characterizing any space weather event is absolute plasma density and plasma density fluctuations, both spatially and temporally. Langmuir probes are the oldest and most proven instruments for these in-situ measurements. This thesis enumerates the development of a miniaturized low-noise Langmuir probe intended for a dual CubeSat mission to study equatorial temperature and wind anomaly in the Earth’s ionosphere.

The Langmuir probe instrument developed is of a planar geometry and fix biased in the ion saturation region, i.e. negative w.r.t. spacecraft chassis. Operating the Langmuir probe in the ion saturation region avoids excessive spacecraft charging …

Precipitation Trends Across The Commonwealth Of Virginia (1947 – 2016), Michael J. Allen, Thomas R. Allen

Virginia Journal of Science

Water is an important resource for the Commonwealth of Virginia. Too much water increases runoff, disrupt transportation networks, and contributes to school closures. Too little water may adversely impact agricultural operations. To improve climate-related information to Virginia citizens, this study assesses means and changes in precipitation across the Commonwealth of Virginia (1947 – 2016). Using daily station-level precipitation data from the Global Historical Climate Network (GHCN), descriptive statistics were calculated for 43 locations in terms of total precipitation (inches decade^-1), precipitation days (x>0”), and heavy precipitation days (x>1.0”). On average, locations showed an overall increase in …

Atmospheric Propagation Of High Energy Lasers: Thermal Blooming Simulation, Jonathan Gustafsson, Benjamin F. Akers, Jonah A. Reeger, Sivaguru S. Sritharan

Faculty Publications

High Energy Laser (HEL) propagation through turbulent atmosphere is examined via numerical simulation. The beam propagation is modeled with the paraxial equation, which in turn is written as a system of equations for a quantum fluid, via the Madelung transform. A finite volume solver is applied to the quantum fluid equations, which supports sharp gradients in beam intensity. The atmosphere is modeled via a coupled advection-diffusion equation whose initial data have Kolmogorov spectrum. In this model the combined effects of thermal blooming, beam slewing, and deep turbulence are simulated.

Performance Of A Customized Cryo-Cooling System Designed For The Measurement Of The Lifetime Of Nuclear Excited States At Cryogenic Temperatures, Innocent J. Lugendo

Tanzania Journal of Science

Theoretical predictions that the lifetime of nuclear excited states can be varied if the nucleus is subjected to a condition that allows multiple coherent emission and re-absorption of gamma photons by the nucleus is of much interest to the nuclear physicists. Therefore, an experiment has been designed to study the possibility of lifetime variation. Based on the theory requirements, lifetime variations can be observed when the nucleus is cooled to cryogenic temperatures. Both the cryo-cooling system and the fast timing system have been developed. In the current work, the design, operation and performance of the developed cryo-cooling system is discussed. …

Statistical Analysis Of Ambient Conditions And Water Temperature On Standard Achievement Of Volume Calibration Of Small Laboratory Glassware, Lazaro Revocatus, Nyimvua Shaban, Isambi S. Mbalawata

Tanzania Journal of Science

Volumetric apparatus calibration is a very sensitive matter in metrological institutions. Identification and evaluation of the uncertainty factors affecting volume calibration of volumetric apparatus such as small laboratory glassware is a critical issue to investigate in order to increase accuracy in calibration.This studyinvestigates the contributions of ambient conditions and water temperature in volume calibration of small laboratory glassware. The study used existing empirical data from the Tanzania Bureau of Standards.The multiple linear regression modelwas used to establish better relationship between explanatory variables and response variable. The model analyzedthree predictor variables namely ambient temperature, pressure and relative humidity. Water temperature was …

Nbc Today Show Features Odu Researchers On Location In Arctic Circle April 1 And 2, Betsy Hnath

News Items

No abstract provided.

Ecological Determinants Of Respiratory Health: Examining Associations Between Asthma Emergency Department Visits, Diesel Particulate Matter, And Public Parks And Open Space In Los Angeles, California, Jason A. Douglas, Reginald S. Archer, Serena E. Alexander

Health Sciences and Kinesiology Faculty Articles

Los Angeles County (LAC) low-income communities of color experience uneven asthma rates, evidenced by asthma emergency department visits (AEDV). This has partly been attributed to inequitable exposure to diesel particulate matter (DPM). Promisingly, public parks and open space (PPOS) contribute to DPM mitigation. However, low-income communities of color with limited access to PPOS may be deprived of associated public health benefits. Therefore, this novel study investigates the AEDV, DPM, PPOS nexus to address this public health dilemma and inform public policy in at-risk communities. Optimized Hotspot Analysis was used to examine geographic clustering of AEDVs, DPM, and PPOS at the …

Source Term Estimation Of Atmospheric Pollutants Using An Ensemble Of Hysplit Concentration Simulations, Casey L. Zoellick

Theses and Dissertations

In support of Comprehensive Nuclear-Test-Ban Treaty (CTBT) monitoring and nuclear event detection, this study works toward source term estimation (STE) of dispersive pollutants using a novel method|an ensemble of forward trajectory concentration simulations using a meteorology-coupled dispersion model. Traditionally a mathematically and physically rigorous problem, STE of a plume of atmospheric pollutants can be solved in a variety of ways depending on what is known regarding the emission, but little has been studied on the sensitivity between the horizontal resolution of the meteorology data in relation to the dispersion model and the results derived from known concentrations at multiple locations. …