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2019

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Articles 181 - 210 of 674

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Integrated Numerical Model For The Simulation Of The T.S. Taipei Oil Spill, Cheng-Di Dong, Thi-Hong-Hanh Nguyen, Tien-Hung Hou, Chia-Cheng Tsai Aug 2019

Integrated Numerical Model For The Simulation Of The T.S. Taipei Oil Spill, Cheng-Di Dong, Thi-Hong-Hanh Nguyen, Tien-Hung Hou, Chia-Cheng Tsai

Journal of Marine Science and Technology–Taiwan

In this study, two freely available models, the hydrodynamic model Princeton Ocean Model (POM) and the oil spill model OpenOil, are integrated to simulate the T.S. Taipei oil spill that occurred on March 10, 2016. In these models, the amount of oil spilled into the sea is distributed among a large number of small and equal mass particles. Meteorological data such as wind velocity, air surface temperature, and current data from the POM are used as inputs. The Lagrangian particle traction with prescribed advection and reaction is used to model the spilled oil. The results are compared with in-situ observations …


Toward Improved Understanding Of Black And Brown Carbon Radiative Impacts Over South Asia, Apoorva Pandey Aug 2019

Toward Improved Understanding Of Black And Brown Carbon Radiative Impacts Over South Asia, Apoorva Pandey

McKelvey School of Engineering Graduate Student Theses & Dissertations

Atmospheric aerosols directly affect the Earth’s radiative budget by absorbing and scattering solar radiation. Carbonaceous aerosols constitute 20-90% of the global aerosol mass burden and are recognized by the Intergovernmental Panel on Climate Change as important drivers of direct radiative forcing (DRF). Aerosol radiative impacts have been implicated in regional atmospheric warming in South Asia: changing Indian monsoon patterns, and accelerating melting of the Himalayan glaciers. There are systematic global discrepancies between estimates of aerosol absorption optical depths derived from observations and those from climate models. Over South Asia, models predict six times lower aerosol absorption than ground-based observations, leading …


Extensive Soot Compaction By Cloud Processing From Laboratory And Field Observations, Janarjan Bhandari, Swarup China, Kamal Kant Chandrakar, Greg Kinney, Will Cantrell, Raymond Shaw, Lynn Mazzoleni, Giulia Girotto, Noopur Sharma, Kyle Gorkowski, Stefania Gilardoni, Stefano Decesari, Maria Cristina Facchini, Nicola Zanca, Giulia Pavese, Francesco Esposito, Manvendra K Dubey, Allison C Aiken, Rajan K Chakrabarty, Hans Moosmüller, Timothy B Onasch, Rahul A Zaveri, Barbara V Scarnato, Paulo Fialho, Claudio Mazzoleni Aug 2019

Extensive Soot Compaction By Cloud Processing From Laboratory And Field Observations, Janarjan Bhandari, Swarup China, Kamal Kant Chandrakar, Greg Kinney, Will Cantrell, Raymond Shaw, Lynn Mazzoleni, Giulia Girotto, Noopur Sharma, Kyle Gorkowski, Stefania Gilardoni, Stefano Decesari, Maria Cristina Facchini, Nicola Zanca, Giulia Pavese, Francesco Esposito, Manvendra K Dubey, Allison C Aiken, Rajan K Chakrabarty, Hans Moosmüller, Timothy B Onasch, Rahul A Zaveri, Barbara V Scarnato, Paulo Fialho, Claudio Mazzoleni

Michigan Tech Publications, Part 1

Soot particles form during combustion of carbonaceous materials and impact climate and air quality. When freshly emitted, they are typically fractal-like aggregates. After atmospheric aging, they can act as cloud condensation nuclei, and water condensation or evaporation restructure them to more compact aggregates, affecting their optical, aerodynamic, and surface properties. Here we survey the morphology of ambient soot particles from various locations and different environmental and aging conditions. We used electron microscopy and show extensive soot compaction after cloud processing. We further performed laboratory experiments to simulate atmospheric cloud processing under controlled conditions. We find that soot particles sampled after …


Seastar: A Mission To Study Ocean Submesoscale Dynamics And Small-Scale Atmosphere-Ocean Processes In Coastal, Shelf And Polar Seas, Christine Gommenginger, Bertrand Chapron, Andy Hogg, Christian Buckingham, Baylor Fox-Kemper, Leif Eriksson, Francois Soulat, Clement Ubelmann, Francisco Ocampo-Torres, Bruno Buongiorno Nardelli, David Griffin, Paco Lopez-Dekker, Per Knudsen, Ole Andersen, Lars Stenseng, Neil Stapleton, William Perrie, Nelson Violante-Carvalho, Johannes Schulz-Stellenfleth, David Woolf, Jordi Isern-Fontanet, Fabrice Ardhuin, Patrice Klein, Alexis Mouche, Ananda Pascual, Xavier Capet, Daniele Hauser, Ad Stoffelen, Rosemary Morrow, Lotfi Aouf, Øyvind Breivik, Lee-Leung Fu, Johnny A. Johannessen, Yevgeny Aksenov, Lucy Bricheno, Joel Hirschi, Adrien C. H. Martin, Adrian P. Martin, George Nurser, Jeff Polton, Judith Wolf, Harald Johnsen, Alexander Soloviev, Gregg A. Jacobs, Fabrice Collard, Steve Groom, Vladimir Kudryavtsev, John Wilkin, Victor Navarro, Alex Babanin, Matthew Martin, John Siddorn, Andrew Saulter, Tom Rippeth, Bill Emery, Nikolai Maximenko, Roland Romeiser, Hans Graber, Aida Alvera Azcarate, Chris W. Hughes, Doug Vandemark, Jose Da Silva, Peter Jan Van Leeuwen, Alberto Naveira-Garabato, Johannes Gemmrich, Amala Mahadevan, Jose Marquez, Yvonne Munro, Sam Doody, Geoff Burbidge Aug 2019

Seastar: A Mission To Study Ocean Submesoscale Dynamics And Small-Scale Atmosphere-Ocean Processes In Coastal, Shelf And Polar Seas, Christine Gommenginger, Bertrand Chapron, Andy Hogg, Christian Buckingham, Baylor Fox-Kemper, Leif Eriksson, Francois Soulat, Clement Ubelmann, Francisco Ocampo-Torres, Bruno Buongiorno Nardelli, David Griffin, Paco Lopez-Dekker, Per Knudsen, Ole Andersen, Lars Stenseng, Neil Stapleton, William Perrie, Nelson Violante-Carvalho, Johannes Schulz-Stellenfleth, David Woolf, Jordi Isern-Fontanet, Fabrice Ardhuin, Patrice Klein, Alexis Mouche, Ananda Pascual, Xavier Capet, Daniele Hauser, Ad Stoffelen, Rosemary Morrow, Lotfi Aouf, Øyvind Breivik, Lee-Leung Fu, Johnny A. Johannessen, Yevgeny Aksenov, Lucy Bricheno, Joel Hirschi, Adrien C. H. Martin, Adrian P. Martin, George Nurser, Jeff Polton, Judith Wolf, Harald Johnsen, Alexander Soloviev, Gregg A. Jacobs, Fabrice Collard, Steve Groom, Vladimir Kudryavtsev, John Wilkin, Victor Navarro, Alex Babanin, Matthew Martin, John Siddorn, Andrew Saulter, Tom Rippeth, Bill Emery, Nikolai Maximenko, Roland Romeiser, Hans Graber, Aida Alvera Azcarate, Chris W. Hughes, Doug Vandemark, Jose Da Silva, Peter Jan Van Leeuwen, Alberto Naveira-Garabato, Johannes Gemmrich, Amala Mahadevan, Jose Marquez, Yvonne Munro, Sam Doody, Geoff Burbidge

Marine & Environmental Sciences Faculty Articles

High-resolution satellite images of ocean color and sea surface temperature reveal an abundance of ocean fronts, vortices and filaments at scales below 10 km but measurements of ocean surface dynamics at these scales are rare. There is increasing recognition of the role played by small scale ocean processes in ocean-atmosphere coupling, upper-ocean mixing and ocean vertical transports, with advanced numerical models and in situ observations highlighting fundamental changes in dynamics when scales reach 1 km. Numerous scientific publications highlight the global impact of small oceanic scales on marine ecosystems, operational forecasts and long-term climate projections through strong ageostrophic circulations, large …


Comparison Between Fluid Simulation With Test Particles And 1 Hybrid Simulation For The Kelvin-Helmholtz Instability, Xuanye Ma, Katariina Nykyri, Brandon L. Burkholder, Rachel C. Rice, Peter A. Delamere, Bishwa Neupane Aug 2019

Comparison Between Fluid Simulation With Test Particles And 1 Hybrid Simulation For The Kelvin-Helmholtz Instability, Xuanye Ma, Katariina Nykyri, Brandon L. Burkholder, Rachel C. Rice, Peter A. Delamere, Bishwa Neupane

Publications

A quantitative investigation of plasma transport rate via the Kelvin‐Helmholtz (KH) instability can improve our understanding of solar‐wind‐magnetosphere coupling processes. Simulation studies provide a broad range of transport rates by using different measurements based on different initial conditions and under different plasma descriptions, which makes cross literature comparison difficult. In this study, the KH instability under similar initial and boundary conditions (i.e., applicable to the Earth's magnetopause environment) is simulated by Hall magnetohydrodynamics with test particles and hybrid simulations. Both simulations give similar particle mixing rates. However, plasma is mainly transported through a few big magnetic islands caused by KH‐driven …


Configuration Files And Input Data Used For Radar Simulations Described In "The Cloud Resolving Model Radar Simulator (Cr-Sim) Version 3.2: Description And Applications Of A Virtual Observatory", Mariko Oue, Toshihisa Matsui, Pavlos Kollias Aug 2019

Configuration Files And Input Data Used For Radar Simulations Described In "The Cloud Resolving Model Radar Simulator (Cr-Sim) Version 3.2: Description And Applications Of A Virtual Observatory", Mariko Oue, Toshihisa Matsui, Pavlos Kollias

SoMAS Research Data

Ground-based observatories use multi-sensor observations to characterize cloud and precipitation properties. A challenge is how to design strategies to best use these observations to understand the atmosphere and evaluate atmospheric numerical prediction models. We have developed the Cloud resolving model Radar SIMulator (CR-SIM), which uses output from high-resolution atmospheric models to emulate multi-wavelength, zenith-pointing, and scanning radar observables and multi-sensor (multi-radar and radar-lidar) integrated products. Here, we publish configuration files used for radar simulations using CR-SIM and atmospheric simulation outputs from the Weather Research Forecasting (WRF) model, which were used as inputs for the radar simulations.


The Role Of A Permeable Sand Column In Modifying Tidal Creek Geochemistry And Land-Derived Inputs To The Coastal Ocean, Nicholas Anthony Legut Aug 2019

The Role Of A Permeable Sand Column In Modifying Tidal Creek Geochemistry And Land-Derived Inputs To The Coastal Ocean, Nicholas Anthony Legut

Electronic Theses and Dissertations

The impairment of regional water quality in Long Bay is an episodic occurrence that has been documented for over a decade. According to one explanation, the occurrence of these events is hypothesized to be the combination of local, terrestrially derived inputs and water-column stratification in the nearshore zone. A portion of these inputs may discharge as surface run-off through estuaries ending in sandy transitional environments termed "swashes". An investigation into the fate of land-derived materials through swashes utilize a linear conservative mixing model to describe the non-conservative behavior of materials in the overlying water and pore-water. This model relies on …


Analysis Algorithm For Sky Type And Ice Halo Recognition In All-Sky Images, Sylke Boyd, Stephen Sorenson, Shelby Richard, Michelle King, Morton Greenslit Aug 2019

Analysis Algorithm For Sky Type And Ice Halo Recognition In All-Sky Images, Sylke Boyd, Stephen Sorenson, Shelby Richard, Michelle King, Morton Greenslit

Physics Publications

Halo displays, in particular the 22∘ halo, have been captured in long time series of images obtained from total sky imagers (TSIs) at various Atmospheric Radiation Measurement (ARM) sites. Halo displays form if smooth-faced hexagonal ice crystals are present in the optical path. We describe an image analysis algorithm for long time series of TSI images which scores images with respect to the presence of 22∘ halos. Each image is assigned an ice halo score (IHS) for 22∘ halos, as well as a photographic sky type (PST), which differentiates cirrostratus (PST-CS), partially cloudy (PST-PCL), cloudy (PST-CLD), or clear (PST-CLR) within …


Calibration Of The Lisst-Vsf To Derive The Volume Scattering Functions In Clear Waters, Lianbo Hu, Xiaodong Zhang, Yuanheng Xiong, Ming-Xia He Aug 2019

Calibration Of The Lisst-Vsf To Derive The Volume Scattering Functions In Clear Waters, Lianbo Hu, Xiaodong Zhang, Yuanheng Xiong, Ming-Xia He

Faculty Publications

The recently commercialized LISST-VSF instrument measures the volume scattering function (VSF) from 0.1° to 15° with a traditional laser diffraction unit (LISST) and from 15° to 155° with an eyeball component. Between these two optical components, only the LISST unit is calibrated. The eyeball measurements are scaled using the VSFs at 15° that are measured by both components. As this relative calibration relies on a valid measurement at 15° by the LISST, it might fail in clear oceanic waters, where the forward scattering is relative weak either due to a lack of large particles or an overall low concentration of …


Weather And Climate Summary And Forecast: August 2019 Report, Gregory V. Jones Aug 2019

Weather And Climate Summary And Forecast: August 2019 Report, Gregory V. Jones

Linfield University Wine Studies Reports

This report provides a summary of the weather and climate forecast for August 2019. It includes forecast information specific to the Pacific Northwest and the western United States, as well as forecast information for other portions of the United States and abroad.


Prediction Of Wind Power Density For Electricity Generation At Makambako, Tanzania Using Auto-Regression Integrated Moving Average (Arima) Model, Josam Samson, Reuben Kainkwa Aug 2019

Prediction Of Wind Power Density For Electricity Generation At Makambako, Tanzania Using Auto-Regression Integrated Moving Average (Arima) Model, Josam Samson, Reuben Kainkwa

Tanzania Journal of Science

Wind speed data used in this study were from Makambako and were recorded at a height of 10 m. In the analysis, the data were extrapolated to 80 m above ground level and wind speed from July to November were found to have an average value of 17.58 m/s. November was found to be the windiest month for the whole duration while the calm month was found to be March. The wind power density was found to be highest in the month of November for the whole study duration. The months of July to November have higher wind power density …


The Effects Of Oil On Blue Crab And Periwinkle Snail Interactions: A Mesocosm Study, Elizabeth M. Robinson, Nancy N. Rabalais Aug 2019

The Effects Of Oil On Blue Crab And Periwinkle Snail Interactions: A Mesocosm Study, Elizabeth M. Robinson, Nancy N. Rabalais

Faculty Publications

We examined the sub-lethal effect of Macondo oil from the Deepwater Horizon oil spill on predator-prey interactions using blue crabs (Callinectes sapidus) and periwinkle snails (Littoraria irrorata). A 2 x 2 factorial mesocosm design determined the effect of oil (no oil vs. oil) and blue crabs (no blue crab predator vs. one blue crab predator) on periwinkle snail climbing and survival. Sixteen mesocosm tanks were used in the experiment, which were replicated three times. Each tank contained water, sand, and Spartina marsh stems. The sixteen tanks were divided between two, temperature-controlled chambers to separate oil treatments (no oil vs. oil). …


2019 August - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University Aug 2019

2019 August - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.


Change In The Leading Mode Of North America's Wintertime Stationary Eddies, Yu-Tang Chien Aug 2019

Change In The Leading Mode Of North America's Wintertime Stationary Eddies, Yu-Tang Chien

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extreme winter weather events in North America have become more frequent and increasingly destructive. This phenomenon was linked to a jet stream pattern that generates abnormally warm conditions in the west and cold conditions in the east, referred to as the North American Winter Dipole. Studies have shown that the Dipole may have amplified and this amplification could be linked to global warming. By analyzing the atmospheric and oceanic data worldwide, the wintertime circulation in the Northern Hemisphere shows signs of a persistent change after the 1980s. In the first part of this study, we examine how the ocean has …


Intermittent Turbulent Exchanges And Their Role In Vineyard Evapotranspiration, Sebastian Alexander Los Aug 2019

Intermittent Turbulent Exchanges And Their Role In Vineyard Evapotranspiration, Sebastian Alexander Los

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Vineyards are often grown in semi-arid climates, such as California’s central valley, where water resources can be limited. Summer weather conditions result in high water use by these plants. For wine grapes, a high-value commodity, there are known benefits to fruit quality in irrigating grapevines with slightly below optimum for the plant. Growers would like to be able to precisely irrigate without overusing water or overstressing the vines. This calls for improving ways to monitor vineyard water use by estimating the combined soil evaporation and plant transpiration known as evapotranspiration (ET). A computer model developed by the USDA called the …


Biogeochemical Controls Of Surface Ocean Phosphate, Adam C. Martiny, Michael W. Lomas, Weiwei Fu, Philip W. Boyd, Yuh-Ling L. Chen, Gregory A. Cutter, Michael J. Ellwood, Ken Furuya, Fuminori Hasshihama, Jota Kanda, David M. Karl, Taketoshi Kodama, Qian P. Li, Jian Ma, Thierry Moutin, E. Malcolm S. Woodward, J. Keith Moore Aug 2019

Biogeochemical Controls Of Surface Ocean Phosphate, Adam C. Martiny, Michael W. Lomas, Weiwei Fu, Philip W. Boyd, Yuh-Ling L. Chen, Gregory A. Cutter, Michael J. Ellwood, Ken Furuya, Fuminori Hasshihama, Jota Kanda, David M. Karl, Taketoshi Kodama, Qian P. Li, Jian Ma, Thierry Moutin, E. Malcolm S. Woodward, J. Keith Moore

OES Faculty Publications

Surface ocean phosphate is commonly below the standard analytical detection limits, leading to an incomplete picture of the global variation and biogeochemical role of phosphate. A global compilation of phosphate measured using high-sensitivity methods revealed several previously unrecognized low-phosphate areas and clear regional differences. Both observational climatologies and Earth system models (ESMs) systematically overestimated surface phosphate. Furthermore, ESMs misrepresented the relationships between phosphate, phytoplankton biomass, and primary productivity. Atmospheric iron input and nitrogen fixation are known important controls on surface phosphate, but model simulations showed that differences in the iron-to-macronutrient ratio in the vertical nutrient supply and surface lateral transport …


New Host Records And Range Extensions For Helminth Parasites From Wading Birds In Southeastern Florida, Sarah Gumbleton, David Kerstetter, Amy Hirons, Christopher Blanar Aug 2019

New Host Records And Range Extensions For Helminth Parasites From Wading Birds In Southeastern Florida, Sarah Gumbleton, David Kerstetter, Amy Hirons, Christopher Blanar

Marine & Environmental Sciences Faculty Articles

Six species of wading birds collected from wildlife centers throughout South Florida were dissected for parasites. Twenty-six species of parasites represent new host records and five parasite species represent new geographic range extensions.


Hydrodynamic Drivers Of Dissolved Oxygen Variability Within A Tidal Creek In Myrtle Beach, South Carolina, Douglas M. Pastore, Richard N. Peterson, Diane B. Fribance, Richard Viso, Erin E. Hackett Aug 2019

Hydrodynamic Drivers Of Dissolved Oxygen Variability Within A Tidal Creek In Myrtle Beach, South Carolina, Douglas M. Pastore, Richard N. Peterson, Diane B. Fribance, Richard Viso, Erin E. Hackett

Marine Science

Beach erosion and water quality degradation have been observed in Singleton Swash, a tidal creek that traverses the beach-face connecting land and ocean in Myrtle Beach, SC. The objective of this study in Singleton Swash is to explore relationships between water quality and hydrodynamics, where the latter are influenced by beach face morphology. We measure water velocities, water levels, and dissolved oxygen concentrations (DO) (a proxy for water quality) and apply correlation analysis to examine the relationships between physical processes and dissolved oxygen variations. Results show that larger tidal ranges are associated with higher mean levels of DO in the …


Microbial Rhodopsins Are Major Contributors To The Solar Energy Captured In The Sea, Laura Gómez-Consarnau, John A. Raven, Naomi M. Levine, Lynda S. Cutter, Deli Wang, Brian Seegers, Javier Arístegui, Jed A. Fuhrman, Josep M. Gasol, Sergio A. Sañudo-Wilhelmy Aug 2019

Microbial Rhodopsins Are Major Contributors To The Solar Energy Captured In The Sea, Laura Gómez-Consarnau, John A. Raven, Naomi M. Levine, Lynda S. Cutter, Deli Wang, Brian Seegers, Javier Arístegui, Jed A. Fuhrman, Josep M. Gasol, Sergio A. Sañudo-Wilhelmy

Research outputs 2014 to 2021

All known phototrophic metabolisms on Earth rely on one of three categories of energy-converting pigments: chlorophyll-a (rarely -d), bacteriochlorophyll-a (rarely -b), and retinal, which is the chromophore in rhodopsins. While the significance of chlorophylls in solar energy capture has been studied for decades, the contribution of retinal-based phototrophy to this process remains largely unexplored. We report the first vertical distributions of the three energy-converting pigments measured along a contrasting nutrient gradient through the Mediterranean Sea and the Atlantic Ocean. The highest rhodopsin concentrations were observed above the deep chlorophyll-a maxima, and their geographical distribution tended to be inversely related to …


Response And Recovery Of Horn And Petit Bois Islands, Mississippi, Usa To Tropical Cyclone Impacts: 2004 – 2016, Shara Gremillion Aug 2019

Response And Recovery Of Horn And Petit Bois Islands, Mississippi, Usa To Tropical Cyclone Impacts: 2004 – 2016, Shara Gremillion

Master's Theses

Horn and Petit Bois islands are two of five Mississippi (MS) barrier islands that provide physical protection from tropical cyclones threatening the MS Gulf Coast, in addition to critical habitat for the northern Gulf of Mexico (GOM). In September 2004, Hurricane Ivan removed a large volume of sediment from the eastern ends of Horn and Petit Bois islands with its 1-2 m storm surge and ~194 kph wind speeds. Then, in August 2005 Hurricane Katrina severely impacted the two islands again with its 3.5-5.5 m storm surge on Horn and Petit Bois islands, and up to 204 kph wind speeds …


Monitoring Tropospheric Gases With Small Unmanned Aerial Systems (Suas) During The Second Cloudmap Flight Campaign, Travis J. Schuyler, Sean C. C. Bailey, Marcelo I. Guzman Aug 2019

Monitoring Tropospheric Gases With Small Unmanned Aerial Systems (Suas) During The Second Cloudmap Flight Campaign, Travis J. Schuyler, Sean C. C. Bailey, Marcelo I. Guzman

Chemistry Faculty Publications

Small unmanned aerial systems (sUAS) are a promising technology for atmospheric monitoring of trace atmospheric gases. While sUAS can be navigated to provide information with higher spatiotemporal resolution than tethered balloons, they can also bridge the gap between the regions of the atmospheric boundary layer (ABL) sampled by ground stations and manned aircraft. Additionally, sUAS can be effectively employed in the petroleum industry, e.g., to constrain leaking regions of hydrocarbons from long gasoducts. Herein, sUAS are demonstrated to be a valuable technology for studying the concentration of important trace tropospheric gases in the ABL. The successful detection and quantification of …


An Observational Study Of Winter Weather-Related Traffic Crashes In Nebraska, Jacob Petr Aug 2019

An Observational Study Of Winter Weather-Related Traffic Crashes In Nebraska, Jacob Petr

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

The responsibilities of meteorologists have evolved over time from simply providing a forecast to needing to also understand how those predictions will impact society and then communicating those risks in a clear, concise, and consistent manner. Increased motor vehicle crash numbers due to adverse weather conditions represent one such impact worthy of further study. Snowfall, in particular, significantly increases the overall risk of a crash, which can result in extensive property damage, severe injuries, and even loss of life.This project seeks to supplement traffic crash information in Nebraska by assessing how snowfall impacts crashes across the state. Crash data were …


The Role Of Boundary-Parallel Vertical Wind Shear In Convection Initiation, Alexander J. Krull Aug 2019

The Role Of Boundary-Parallel Vertical Wind Shear In Convection Initiation, Alexander J. Krull

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

Convection initiation (CI) remains a forecasting challenge for meteorologists. CI frequently occurs within the vicinity of some airmass boundary or density current. Airmass boundaries are favored areas of convergence, thus associated forced ascent facilitates CI. Features such as misocyclones often develop along the leading edge of airmass boundaries, favoring updraft formation and prompting alterations to the horizontal and vertical flow near the boundary. Airmass boundary characteristics and CI potential have been found to be sensitive to the environmental vertical wind shear. This affects propagation speed, convergence, and thus forced ascent along the leading edge. Previous studies have focused primarily on …


Adsorption Driven Regolith-Atmospheric Water Vapor Transfer On Mars: An Analysis Of Phoenix Tecp Data, Holly Nicole Farris Aug 2019

Adsorption Driven Regolith-Atmospheric Water Vapor Transfer On Mars: An Analysis Of Phoenix Tecp Data, Holly Nicole Farris

Graduate Theses and Dissertations

NASA’s Phoenix mission allowed for investigations of Martian diurnal water vapor cycles through the collection of temperature, relative humidity, and electric conductivity data by the Thermal and Electric Conductivity Probe (TECP) instrument. Using this data and previous experimental data, we propose a regolith-driven adsorption-desorption regime at the Phoenix landing site, where parameters intrinsic to the regolith are controlling localized relative humidity at the surface. To constrain these parameters, we model adsorption as a function of temperature and relative humidity across various Mars-relevant materials, defined by two layer-based adsorption theories: Langmuir (monolayer) and Brunauer-Emmett-Teller or BET (multilayer). Langmuir serves as an …


Evaluating Responses Of Benthic Macrofauna To Artificial Reef Presence In The Gulf Of Mexico, Douglas Faircloth Aug 2019

Evaluating Responses Of Benthic Macrofauna To Artificial Reef Presence In The Gulf Of Mexico, Douglas Faircloth

Theses and Dissertations

Artificial reef research has long concerned itself with the interactions of fishes and has tended to favor commercially valuable species. Because of this, a larger yet less known group that heavily benefits fishes have been overlooked; benthic macrofauna. Benthic macrofauna are marine invertebrates that live below the sediment-water interface and play many roles in the ecosystem. Macrofauna are important prey items, ecosystem engineers, and bioindicators, as well as being ubiquitous in the marine environment. Since macrofauna have been largely ignored in this field, not much is known regarding their interaction with the placement of artificial reefs. To try and fill …


Developing Multispectral Imaging Techniques To Determine Canopy Coverage And Carbon Storage Of Seagrasses In The Gulf Of Mexico, Ivy Michelle Hinson Aug 2019

Developing Multispectral Imaging Techniques To Determine Canopy Coverage And Carbon Storage Of Seagrasses In The Gulf Of Mexico, Ivy Michelle Hinson

Theses and Dissertations

Although seagrass beds provide global ecosystem services, coverage is in rapid decline, with the capacity of seagrasses to sequester carbon of special concern. Current seagrass monitoring methods are labor intensive and may not offer a complete picture of coverage. Remote sensing offers the ability to oversee landscapes but water in coastal environments presents challenges, as the commonly used near-infrared wavelength dissipates in water.

This project aimed to provide reliable methodology to assess seagrass coverage using multispectral imagery taken from an unmanned aerial vehicle and to provide evidence for the link between seagrass coverage and stored belowground carbon for common seagrasses …


Non-Linear Magnetosphere-Ionosphere Interactions At High Latitudes, Beket Tulegenov Aug 2019

Non-Linear Magnetosphere-Ionosphere Interactions At High Latitudes, Beket Tulegenov

Doctoral Dissertations and Master's Theses

Non-linear, 3D electromagnetic coupling between the ionosphere and magnetosphere is investigated in this dissertation. The study is based on a non-linear, 3D, reduced magnetohydrodynamic model describing interaction between dispersive Alfven waves and the nightside high-latitude ionosphere. Results are presented from a numerical study of small-scale, intense magnetic field-aligned currents observed in the vicinity of the discrete auroral arc by the Magnetosphere-Ionosphere Coupling in the Alfven Resonator (MICA) sounding rocket launched from Poker Flat, Alaska, on 19 February 2012. The goal of the MICA project was to investigate the hypothesis that such currents can be produced inside the ionospheric Alfven resonator …


Spatio-Temporal Analysis Of Tree Ring Chronology And Precipitation, Ruizhe Yin Aug 2019

Spatio-Temporal Analysis Of Tree Ring Chronology And Precipitation, Ruizhe Yin

Graduate Theses and Dissertations

Tree ring chronology data is known to reflect regional climate due to the strong impact of rainfall and temperature. Therefore, tree ring data can be used to reconstruct historical climate in order to understand how climate changed in the past and make prediction about the future behavior of the climate. For simplicity, this research only considers the influence of precipitation on tree ring growth within the New England area. A total of 94 measurement sites are used to record tree ring width over 881 years and corresponding precipitation data are given at some locations for 121 years. We developed a …


Engineered Carbon-Nanocatalyst Composites And Carbon Mixed ‎Matrix Membranes ‎For Water And Wastewater Treatment ‎, Mojtaba Abolhassani Aug 2019

Engineered Carbon-Nanocatalyst Composites And Carbon Mixed ‎Matrix Membranes ‎For Water And Wastewater Treatment ‎, Mojtaba Abolhassani

Graduate Theses and Dissertations

Carbonaceous materials such as graphene oxide, and activated ‎carbon have a wide range of ‎applications in water and wastewater treatment due to the high surface ‎area, unique structure, ‎and chemical and thermal stability. Carbon-based materials can be used as a ‎membrane, an ‎adsorbent, a support for nanomaterials, or ‎as a filler within membranes to remove contaminants ‎from water. In this research, the specific carbon materials and how their properties influence their ‎use and performance in ‎specific engineering applications is explored. ‎

Here, membrane filtration and adsorption/degradation of the water and wastewater using carbon-‎based material are investigated. The research firstly focuses …


Analysis Of Hurricane Track Forecast Accuracy During The 2018 Season, Jonathan D. Unger Jul 2019

Analysis Of Hurricane Track Forecast Accuracy During The 2018 Season, Jonathan D. Unger

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Hurricane track forecasting has become more accurate in recent years due to technological advances in modeling methods. However, due to the complex nature of the relationship between oceanic and atmospheric variables and hurricane tracks, noteworthy errors in track prediction, especially for predictions several days into the future, still remain. In this study, two different methods of forecasting hurricane tracks are compared. Using the four United States landfalling hurricanes of the 2018 season as a sample, the official forecast tracks published by the National Hurricane Center (NHC) and hypothetical tracks based purely on climatology were mapped simultaneously with the preliminary best …