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Articles 3601 - 3630 of 13989

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

If Watersheds Spoke: A Condition Analysis Of The Rio Tomebamba Watershed In Southern Ecuador Using Gis Analysis, Lenka G. Doskocil Apr 2020

If Watersheds Spoke: A Condition Analysis Of The Rio Tomebamba Watershed In Southern Ecuador Using Gis Analysis, Lenka G. Doskocil

Independent Study Project (ISP) Collection

Understanding processes and ecological threats occurring at the watershed level scale composes a critical piece of water resource conservation and management. This proves doubly true in areas such as the Ecuadorian highlands where water resources depend heavily on the hydrologic regulation capacities of páramo soils. This study examined watershed condition of the Rio Tomebamba watershed and existing habitat for Metallura baroni and Chibchanomys orcesi, two highly endemic species, within its boundaries. Watershed condition was determined based on a simple index that considered nine indicators of watershed health—converted land, impacted riparian zones, impermeable surfaces, water quality, fluvial habitat condition, riparian vegetation …


Trend Analyses Of The Abundances Of Atmospheric Molecules, Anton Fernando Apr 2020

Trend Analyses Of The Abundances Of Atmospheric Molecules, Anton Fernando

Physics Theses & Dissertations

A new line list for the A3Π - X3Σ- electronic transition of NH has been prepared using line positions from the literature and calculated line intensities. High level ab initio calculations were performed with the MOLPRO program to obtain the A - X transition dipole moment function. Potential energy curves and line strengths were calculated with Le Roy's RKR1 and LEVEL programs. Line intensities and Einstein A values were calculated with Western's PGOPHER program after converting the Hund's case (b) output of LEVEL to Hund's case (a) input needed for PGOPHER. The Herman- Wallis effect is …


The Role Of Island-Marsh Couplings In The Long-Term Sustainability Barrier Islands In The Face Of Accelerated Sea-Level Rise, Christopher Hein Mar 2020

The Role Of Island-Marsh Couplings In The Long-Term Sustainability Barrier Islands In The Face Of Accelerated Sea-Level Rise, Christopher Hein

Sustainability Seminar Series

Barrier islands are one of the most ubiquitous features of the coast . . . at least here along the US East Coast, which accounts for >10% of the world’s barrier islands. Little more than large, partially vegetated, subaerial sand bars, barrier island provide for recreation, ecosystem services, and protection of mainland communities from storm impacts. They are also some of the most dynamic features on earth, constantly changing in the face of waves, tides, wind, and currents. With examples from northern Massachusetts and the Virginia Eastern Shore, this talk will focus on the long-term sustainability of barrier islands, and …


Seasonal Patterns Of Surface Inorgamic Carbon System Variables In The Gulf Of Mexico Inferred From A Regional High-Resolution Ocean Biogeochemical Model, Fabian A. Gomez, Rik Wanninkhof, Leticia Barbero, Sang Ki Lee, Frank J. Hernandez Mar 2020

Seasonal Patterns Of Surface Inorgamic Carbon System Variables In The Gulf Of Mexico Inferred From A Regional High-Resolution Ocean Biogeochemical Model, Fabian A. Gomez, Rik Wanninkhof, Leticia Barbero, Sang Ki Lee, Frank J. Hernandez

Faculty Publications

Uncertainties in carbon chemistry variability still remain large in the Gulf of Mexico (GoM), as data gaps limit our ability to infer basin-wide patterns. Here we configure and validate a regional high-resolution ocean biogeochemical model for the GoM to describe seasonal patterns in surface pressure of CO2 (pCO2), aragonite saturation state (ΩAr), and sea–air CO2 flux. Model results indicate that seasonal changes in surface pCO2 are strongly controlled by temperature across most of the GoM basin, except in the vicinity of the Mississippi–Atchafalaya river system delta, where runoff largely controls dissolved inorganic carbon (DIC) …


Polycyclic Aromatic Hydrocarbon Exposure, Hepatic Accumulation, And Associated Health Impacts In Gulf Of Mexico Tilefish (Lopholatilus Chamaeleonticeps), Susan M. Snyder Mar 2020

Polycyclic Aromatic Hydrocarbon Exposure, Hepatic Accumulation, And Associated Health Impacts In Gulf Of Mexico Tilefish (Lopholatilus Chamaeleonticeps), Susan M. Snyder

USF Tampa Graduate Theses and Dissertations

Following the 2010 Deepwater Horizon oil spill, systematic demersal longline surveys were conducted throughout the Gulf of Mexico (GoM) continental shelf to evaluate polycyclic aromatic hydrocarbon (PAH) exposure, hepatic accumulation, and health indices in demersal fishes. Tilefish (Lopholatilus chamaeleonticeps) were chosen as a target species due to high vulnerability to environmental disturbance, commercial importance, Gulf-wide distribution, and documented high exposure to PAHs post-Deepwater Horizon. Over 200 Tilefish were sampled in the north central GoM at repeat stations from 2012 to 2017, and from the northwest GoM, southwest GoM, Bay of Campeche, and Yucatán Shelf over years 2015 and 2016. Tilefish …


Chemical Crises In A Changing Ocean Ocg 104g, Joanna Burkhardt Mar 2020

Chemical Crises In A Changing Ocean Ocg 104g, Joanna Burkhardt

Library Impact Statements

No abstract provided.


Large Thecosome Pteropods Of The Northern Gulf Of Mexico: Species Abundance, Spatial And Vertical Distribution With A Temporal Comparison Of Shell Thickness, Sarah M. Shedler Mar 2020

Large Thecosome Pteropods Of The Northern Gulf Of Mexico: Species Abundance, Spatial And Vertical Distribution With A Temporal Comparison Of Shell Thickness, Sarah M. Shedler

USF Tampa Graduate Theses and Dissertations

Large thecosome pteropods have a significant role in the pelagic ecosystem of the northern Gulf of Mexico (GoM). This research analyzed species abundances, vertical and horizontal distributions, and trends in shell thickness between 2011 and 2015. Pteropod samples were collected following the 2010 Deepwater Horizon oil spill by two midwater sampling programs: the Offshore Nekton Sampling and Analysis Program (ONSAP, 2011) and the Deep Pelagic Nekton Dynamics of the Gulf of Mexico (DEEPEND, 2015). All samples were collected using a 10-m2 Multiple Opening/Closing Net and Environmental Sensing System (MOC10) midwater trawl, with 3-mm mesh size. This gear sampled five discrete …


The Temporal And Spatial Distribution Of Wind Factor In Iraq, Azhaar Mishaal, Sura Nassir, Ahmed Badr Khamees, Mudar Ahmed Abdulsattar Mar 2020

The Temporal And Spatial Distribution Of Wind Factor In Iraq, Azhaar Mishaal, Sura Nassir, Ahmed Badr Khamees, Mudar Ahmed Abdulsattar

Karbala International Journal of Modern Science

This work aims to study wind factor 10 m above the ground level for different stations in Iraq for determining the promising regions in the field of wind energy. For this purpose, the use of data (Wind Speed) for 25 years is performed. Missing data may occur within the time series of processing. Calculations are performed by using the statistical model (ARIMA model). The analysis of data is performed by using the Geographic Information System Program (Arc map). The temporal and spatial distribution of wind speed shows that the high value during the summer and the autumn in the southern …


An Analysis Of A Lighting Prediction Threshold For 45th Weather Squadron Electric Field Mill Data, Charles A. Skrovan Mar 2020

An Analysis Of A Lighting Prediction Threshold For 45th Weather Squadron Electric Field Mill Data, Charles A. Skrovan

Theses and Dissertations

The mission of the 45th Weather Squadron (45 WS) is to “exploit the weather to assure safe access to air and space” for Patrick Air Force Base, Cape Canaveral Air Force Station (CCAFS), and Kennedy Space Center (KSC) in support of various operations (United States Air Force, n.d.). To support that mission the 45 WS hosts a suite of weather detection instruments that include a lightning warning system that consists of an array of 31 electric field mills (EFM) and a lightning detection and ranging system (Department of the Air Force, 1976). Electric field mills at Cape Canaveral continuously record …


Validation Technique For Modeled Bottomside Ionospheres Via Ray Tracing, Kevin S. Burg Mar 2020

Validation Technique For Modeled Bottomside Ionospheres Via Ray Tracing, Kevin S. Burg

Theses and Dissertations

A new method for validating ionosphere models using High Frequency (HF) angle of arrival (AoA) data is presented. AoA measurements from a field campaign held at White Sands Missile Range, New Mexico, USA in January 2014 provide the actual elevation angle, azimuth and group delay results from 10 transmitter-receiver circuits. Simulated AoAs are calculated by ray tracing through the electron density profiles predicted from the ionosphere models hosted by NASA's Community Coordinated Modeling Center: IRI-2016, USU-GAIM, GITM, CTIPe, TIE-GCM, and SAMI3. Through the implementation of metrics including Mean Absolute Error, Prediction Efficiency, Correlation Coefficient, and others, we are able to …


A Polarimetric Radar Analysis Of Cold- And Warm-Based Supercells, Timothy J. Gunkel Mar 2020

A Polarimetric Radar Analysis Of Cold- And Warm-Based Supercells, Timothy J. Gunkel

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

Polarimetric analyses of supercell thunderstorms have been increasingly common within the past decade, since operational polarimetric radar data became available in 2013. Although polarimetric signatures within supercell thunderstorms are well known, few have investigated variability in these signatures in differing environments. Polarimetric signatures can provide vital information regarding the microphysical characteristics and processes in supercell thunderstorms. Specific polarimetric signatures of interest are the differential reflectivity (ZDR) column, the low-level polarimetrically inferred hail core, and the ZDR arc. These signatures provide information regarding updraft characteristics, hailfall characteristics, and size sorting processes in the storm- relative inflow. Previous studies …


Phytoplankton And Carbon Dynamics In The Estuarine-Coastal Waters Of The Northern Gulf Of Mexico From Field Data And Ocean Color Remote Sensing, Bingqing Liu Mar 2020

Phytoplankton And Carbon Dynamics In The Estuarine-Coastal Waters Of The Northern Gulf Of Mexico From Field Data And Ocean Color Remote Sensing, Bingqing Liu

LSU Doctoral Dissertations

In this study, phytoplankton community and carbon dynamics were examined in the optically complex estuarine-coastal regions of the northern Gulf of Mexico (nGOM) from field and satellite ocean color observations. As part of this study, bio-optical ocean color algorithms for i) dissolved organic carbon (DOC), ii) phytoplankton pigment composition, iii) adaptive estimation of Chl a and iv) phytoplankton size fractions were developed to facilitate the study of biogeochemical cycling in the nGOM.

The phytoplankton based algorithms were applied to Sentinel 3A/B-OLCI oean color data to assess phytoplankton community dynamics to extreme river discharge conditions as well as hurricanes in the …


Changes In Atmospheric, Meteorological, And Ocean Parameters Associated With The 12 January 2020 Taal Volcanic Eruption, Feng Jing, Akshansa Chauhan, Ramesh P. Singh, Prasanjit Dash Mar 2020

Changes In Atmospheric, Meteorological, And Ocean Parameters Associated With The 12 January 2020 Taal Volcanic Eruption, Feng Jing, Akshansa Chauhan, Ramesh P. Singh, Prasanjit Dash

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The Taal volcano erupted on 12 January 2020, the first time since 1977. About 35 mild earthquakes (magnitude greater than 4.0) were observed on 12 January 2020 induced from the eruption. In the present paper, we analyzed optical properties of volcanic aerosols, volcanic gas emission, ocean parameters using multi-satellite sensors, namely, MODIS (Moderate Resolution Imaging Spectroradiometer), AIRS (Atmospheric Infrared Sounder), OMI (Ozone Monitoring Instrument), TROPOMI (TROPOspheric Monitoring Instrument) and ground observations, namely, Argo, and AERONET (AErosol RObotic NETwork) data. Our detailed analysis shows pronounced changes in all the parameters, which mainly occurred in the western and south-western regions because the …


Microbial Symbionts And Ecological Divergence Of Caribbean Sponges: A New Perspective On An Ancient Association, Christopher Freeman, Cole Easson, Kenan O. Matterson, Robert W. Thacker, David M. Baker, Valerie J. Paul Mar 2020

Microbial Symbionts And Ecological Divergence Of Caribbean Sponges: A New Perspective On An Ancient Association, Christopher Freeman, Cole Easson, Kenan O. Matterson, Robert W. Thacker, David M. Baker, Valerie J. Paul

Marine & Environmental Sciences Faculty Articles

Marine sponges host diverse communities of microbial symbionts that expand the metabolic capabilities of their host, but the abundance and structure of these communities is highly variable across sponge species. Specificity in these interactions may fuel host niche partitioning on crowded coral reefs by allowing individual sponge species to exploit unique sources of carbon and nitrogen, but this hypothesis is yet to be tested. Given the presence of high sponge biomass and the coexistence of diverse sponge species, the Caribbean Sea provides a unique system in which to investigate this hypothesis. To test for ecological divergence among sympatric Caribbean sponges …


Testing The Efficacy Of Recompression Tools To Reduce The Discard Mortality Of Reef Fishes In The Gulf Of Mexico, Oscar E. Ayala Mar 2020

Testing The Efficacy Of Recompression Tools To Reduce The Discard Mortality Of Reef Fishes In The Gulf Of Mexico, Oscar E. Ayala

USF Tampa Graduate Theses and Dissertations

In order to enhance the recovery of overfished stocks, fishery managers have implemented increasingly restrictive harvest regulations. However, discarded fish are susceptible to mortality from barotrauma when retrieved from depth. Venting tools are commonly used to enable fish to return to their depth of capture. An alternative method has been developed that involves the rapid descent of fish to their depth of capture to reduce buoyancy. In the Gulf of Mexico, the released portion of Red Snapper (Lutjanus campechanus) and Red Grouper (Epinephelus morio) has exceeded 80% of total catch. I tested the survival of these two economically important species …


Methanethiol, Dimethyl Sulfide And Acetone Over Biologically Productive Waters In The Southwest Pacific Ocean, Sarah J. Lawson, Cliff S. Law, Mike J. Harvey, Thomas G. Bell, Carolyn F. Walker, Warren J. De Bruyn, Eric S. Saltzman Mar 2020

Methanethiol, Dimethyl Sulfide And Acetone Over Biologically Productive Waters In The Southwest Pacific Ocean, Sarah J. Lawson, Cliff S. Law, Mike J. Harvey, Thomas G. Bell, Carolyn F. Walker, Warren J. De Bruyn, Eric S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Atmospheric methanethiol (MeSHa), dimethyl sulfide (DMSa) and acetone (acetonea) were measured over biologically productive frontal waters in the remote southwest Pacific Ocean in summertime 2012 during the Surface Ocean Aerosol Production (SOAP) voyage. MeSHa mixing ratios varied from below the detection limit (< 10 ppt) up to 65 ppt and were 3 %–36 % of parallel DMSa mixing ratios. MeSHa and DMSa were correlated over the voyage (R2=0.3, slope = 0.07) with a stronger correlation over a coccolithophore-dominated phytoplankton bloom (R2=0.5, slope 0.13). The diurnal cycle for MeSHa shows similar behaviour to DMSa with mixing ratios …


Antibiotic Resistance In Marine Microbial Communities Proximal To A Florida Sewage Outfall System, Dale W. Griffin, Kenneth Banks, Kurtis Gregg, Sarah Shedler, Brian K. Walker Mar 2020

Antibiotic Resistance In Marine Microbial Communities Proximal To A Florida Sewage Outfall System, Dale W. Griffin, Kenneth Banks, Kurtis Gregg, Sarah Shedler, Brian K. Walker

Marine & Environmental Sciences Faculty Articles

Water samples were collected at several wastewater treatment plants in southeast Florida, and water and sediment samples were collected along and around one outfall pipe, as well as along several transects extending both north and south of the respective outfall outlet. Two sets of samples were collected to address potential seasonal differences, including 38 in the wet season (June 2018) and 42 in the dry season (March 2019). Samples were screened for the presence/absence of 15 select antibiotic resistance gene targets using the polymerase chain reaction. A contrast between seasons was found, with a higher frequency of detections occurring in …


Light Organ Photosensitivity In Deep-Sea Shrimp May Suggest A Novel Role In Counterillumination, Heather D. Bracken-Grissom, Danielle M. Deleo, Megan L. Porter, Tom Iwanicki, Jamie E. Sickles, Tamara Frank Mar 2020

Light Organ Photosensitivity In Deep-Sea Shrimp May Suggest A Novel Role In Counterillumination, Heather D. Bracken-Grissom, Danielle M. Deleo, Megan L. Porter, Tom Iwanicki, Jamie E. Sickles, Tamara Frank

Marine & Environmental Sciences Faculty Articles

Extraocular photoreception, the ability to detect and respond to light outside of the eye, has not been previously described in deep-sea invertebrates. Here, we investigate photosensitivity in the bioluminescent light organs (photophores) of deep-sea shrimp, an autogenic system in which the organism possesses the substrates and enzymes to produce light. Through the integration of transcriptomics, in situ hybridization and immunohistochemistry we find evidence for the expression of opsins and phototransduction genes known to play a role in light detection in most animals. Subsequent shipboard light exposure experiments showed ultrastructural changes in the photophore similar to those seen in crustacean eyes, …


Investigation Of Retention Versus Export Of Planktonic Fish Eggs In The Northeastern Gulf Of Mexico, Bich Vi Viviane Nguyen Mar 2020

Investigation Of Retention Versus Export Of Planktonic Fish Eggs In The Northeastern Gulf Of Mexico, Bich Vi Viviane Nguyen

USF Tampa Graduate Theses and Dissertations

Planktonic fish eggs can be reliably identified with DNA barcoding, and their distribution and abundance can be monitored. Passive drifting fish eggs can be advected by ocean currents and as a result, can either be locally retained or exported away from the West Florida Shelf (WFS). Investigating their retention or export helps in the interpretation of egg abundance trends and in understanding their distribution in long-term surveys. The present investigation was performed in two steps using a combination of biological and physical oceanographic methods. First, fish fecundity of three species (Red Snapper, Vermilion Snapper, and Sand Perch) was assessed, first, …


What Is The Most Threatening Disaster To The Continental United States?, Aaron Spomer, Elijah Kaufman, Julisa Prieto-Garcia, Brooke Aschwanden Mar 2020

What Is The Most Threatening Disaster To The Continental United States?, Aaron Spomer, Elijah Kaufman, Julisa Prieto-Garcia, Brooke Aschwanden

UNO Student Research and Creative Activity Fair

Our goal for our project is to fully understand which natural disaster is the most destructive to the United States. We have chosen to compare hurricanes, floods, tornadoes, wildfires, earthquakes, and nor’easters. We have researched the cost of the total damage and repair, how the warning systems have improved over time, the death tolls from each, and also the frequency at which each one occurs. Each group member will research a different disaster impact, and the data will create a comprehensive view of the level of devastation each disaster has. We collected data all the way from the early 1900s …


Weather And Climate Summary And Forecast: March 2020 Report, Gregory V. Jones Mar 2020

Weather And Climate Summary And Forecast: March 2020 Report, Gregory V. Jones

Linfield University Wine Studies Reports

This report provides a summary of the weather and climate forecast for March 2020. 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.


Reproductive Ecology Of Dragonfishes (Stomiiformes: Stomiidae) In The Gulf Of Mexico, Alex Marks, David Kerstetter, David Wyanski, Tracey Sutton Mar 2020

Reproductive Ecology Of Dragonfishes (Stomiiformes: Stomiidae) In The Gulf Of Mexico, Alex Marks, David Kerstetter, David Wyanski, Tracey Sutton

Marine & Environmental Sciences Faculty Articles

The most abundant fishes on Earth live in the meso- and bathypelagic (deep-pelagic, collectively) zones of the open ocean, where they play a key role in deep-sea food webs by mediating energy flow from surface waters to great depth. Of these fishes, the most speciose taxon is the family Stomiidae (dragonfishes). Despite being the numerically dominant predators of the global mesopelagic zone, stomiid reproductive ecology is poorly known. Research surveys rarely catch larger adults, impeding reproductive ecology studies. Between 2010 and 2011, the Offshore Nekton Sampling and Analysis Program sampled the Gulf of Mexico using a research-sized, opening/closing trawl (10-m …


Effect Of Channelized And Unchannelized Lateral Outflow On Three-Dimensional Flow Structure And Sediment Transport Mechanisms In A River Delta, Mohammad Kifayath Chowdhury Mar 2020

Effect Of Channelized And Unchannelized Lateral Outflow On Three-Dimensional Flow Structure And Sediment Transport Mechanisms In A River Delta, Mohammad Kifayath Chowdhury

LSU Master's Theses

Spatial and temporal patterns in three-dimensional flow structure have been linked to channel morphology and processes in many environments, including river meander bends, confluences-diffluences, and bedrock canyons. However, there is not yet an understanding of how channelized and gradual, distributed lateral outflows that are often prevalent in deltaic distributary systems influence three-dimensional flow structure and sediment transport mechanisms. This thesis presents an analysis of 3D flow structure data collected from Wax Lake Delta, a naturally developing river-dominated delta in the northern Gulf of Mexico. Three hydrographic surveys were conducted using boat-mounted acoustic Doppler current profiler (ADCP) at two sites: an …


Utilizing Objective Drought Severity Thresholds To Improve Drought Monitoring, Zachary T. Leasor, Steven M. Quiring, Mark D. Svoboda Mar 2020

Utilizing Objective Drought Severity Thresholds To Improve Drought Monitoring, Zachary T. Leasor, Steven M. Quiring, Mark D. Svoboda

National Drought Mitigation Center: Faculty Publications

Drought is a prominent climatic hazard in the south-central United States. Drought severity is frequently classified using the categories established by the U.S. Drought Monitor (USDM). This study evaluates whether the thresholds for the standardized precipitation index (SPI) used by the USDM accurately classify drought severity. This study uses the SPI based on PRISM precipitation data from 1900 to 2015 to evaluate drought severity in Texas, Oklahoma, and Kansas. The results show that the fixed SPI thresholds for the USDM drought categories may lead to a systematic underestimation of drought severity in arid regions. To address this issue, objective drought …


Rockhounding, Seafaring, And Other Material Tales For The End Of The World, Noemie Fortin Mar 2020

Rockhounding, Seafaring, And Other Material Tales For The End Of The World, Noemie Fortin

The Goose

In the face of accelerated environmental degradation and climate instability, the future of the Earth and of all life on earth is difficult to visualize. Therefore, the different mediums through which we consider environmental issues are just as important as the actions we take to address them. Focusing on three projects combining art, science, and activism, this article suggests a compilation of material tales. They tell stories of plastic rocks and aluminum nuggets where the protagonists are partly finely crafted objects, partly waste materials, and sometimes both at once. Artists Kelly Jazvac, Yesenia Thibeault-Picazo, and the collective Studio Swine collaborate …


Next-Generation Air Force Weather Metrics Via Bayes Cost Analysis, Brandon M. Bailey Mar 2020

Next-Generation Air Force Weather Metrics Via Bayes Cost Analysis, Brandon M. Bailey

Theses and Dissertations

This research proposes a new methodology for U.S. Air Force weather forecast metrics. Military weather forecasters are essentially statistical classifiers. They categorize future conditions into an operationally relevant category based on current data, much like an Artificial Neural Net or Logistic Regression model. There is extensive literature on statistically-based metrics for these types of classifiers. Additionally, in the U.S. Air Force, forecast errors (errors in classification) have quantifiable operational costs and benefits associated with incorrect or correct classification decisions. There is a methodology in the literature, Bayes Cost, which provides a structure for creating statistically rigorous metrics for classification decisions …


Detection Of Reconnection Signatures In Solar Flares, Taylor R. Whitney Mar 2020

Detection Of Reconnection Signatures In Solar Flares, Taylor R. Whitney

Theses and Dissertations

Solar flare forecasting is limited by the current understanding of mechanisms that govern magnetic reconnection, the main physical phenomenon associated with these events. As a result, forecasting relies mainly on climatological correlations to historical events rather than the underlying physics principles. Solar physics models place the neutral point of the reconnection event in the solar corona. Correspondingly, studies of photospheric magnetic fields indicate changes during solar flares -- particularly in relation to the field helicity -- on the solar surface as a result of the associated magnetic reconnection. This study utilizes data from the Solar Dynamics Observatory (SDO) Helioseismic and …


Determining Bulk Aerosol Absorption From Off Axis Backscattering Using Rayleigh Beacon Laser Pulses, Julie C. Grossnickle Mar 2020

Determining Bulk Aerosol Absorption From Off Axis Backscattering Using Rayleigh Beacon Laser Pulses, Julie C. Grossnickle

Theses and Dissertations

Aerosol absorption and scattering can play a key role in degrading high energy laser performance in the form of thermal blooming and beam attenuation. Aerosol absorption properties are not completely understood, and thus affect how we are able to quantify expected high energy laser weapon performance. The Air Force Institute of Technology Center for Directed Energy (AFIT CDE) developed both Laser Environmental Effects Definition and Reference (LEEDR) and the High Energy Laser End-to-End Operational Simulation (HELEEOS) code to characterize atmospheric radiative transfer effects and evaluate expected directed energy weapon system performance. These packages enable modeling of total irradiance at given …


Modulation Of Lightning Occurrence By The Solar Wind, Adam L. Baxter Mar 2020

Modulation Of Lightning Occurrence By The Solar Wind, Adam L. Baxter

Theses and Dissertations

Lightning affects military and civilian operations. Characterization of the distribution of global lightning strikes of two detection networks based on solar wind events is analyzed. the median analysis by latitude gave different results for the two network datasets. The KLD pulled out some common features such as the seasonal dependence and a general increase in lightning at the equator. Comparisons between different datasets must be handled carefully. the KLD method may be a way to capture common features, or assess how similar the datasets are. A detailed analysis of the differences between the tow networks detection algorithms and investigating other …


A Method For Routine Pm2.5 Obsercation And Incorporation Into Numerical Weather Prediction, Daniel B. Jagoda Mar 2020

A Method For Routine Pm2.5 Obsercation And Incorporation Into Numerical Weather Prediction, Daniel B. Jagoda

Theses and Dissertations

Operational numerical weather prediction (NWP) simulates aerosol abundance using climatic emission inventories due to a lack of available real-time observation. An advocation to monitor aerosol number concentration with a standardized global sensor network is defended. A comparison between observations from the existing network “PurpleAir” and condensation particle counters (CPC) reveals the necessity of regulated instrumentation when measuring aerosol number concentration. NWP initialization by the Goddard Chemistry Aerosol Radiation and Transport (GOCART) module is capable of augmentation by hourly aerosol observation. The disparity between observed in-situ particulate matter smaller than 2.5-μm in diameter (PM2.5) and Weather Research and Forecasting …