Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Keyword
-
- Meteorology (3)
- Weather forecasting (3)
- District of Columbia (2)
- Lightning (2)
- Thunderstorms (2)
-
- African Great Lakes (1)
- Algorithms (1)
- Andragogy (1)
- Argentina (1)
- Atmospheric sciences (1)
- Bangladesh (1)
- Biogeochemistry (1)
- CCAFS (Cape Canaveral Air Force Station) (1)
- CI (1)
- CWE (Convective Wind Events) (1)
- Carbon dioxide exchange (1)
- Carbon dynamics (1)
- Change detection (1)
- Chicago (1)
- Climate (1)
- Climate Change (1)
- Climate literacy (1)
- Cloud cover (1)
- Cold season precipitation (1)
- Convection (1)
- Convective Winds (1)
- Data set (1)
- Decadal (1)
- Detrital zircons (1)
- Downburst Frequency (1)
Articles 1 - 23 of 23
Full-Text Articles in Physical Sciences and Mathematics
Multidecadal Variability In Climate Models And Observations, Alex Carl Oser
Multidecadal Variability In Climate Models And Observations, Alex Carl Oser
Theses and Dissertations
Climate change attribution and prediction using state-of-the-art models continue to garner an ever-growing focus amongst both the scientific community and public alike. Recent analyses showing discrepancies in the structure of modeled and observed decadal climate variability (DCV), therefore, have engendered efforts to not only diagnose the dynamics underpinning observed DCV, but also to characterize the behavior of DCV within climate models. In this thesis, we employ Multichannel Singular Spectrum Analysis (M-SSA) to show that while the DCV signal in observations is best described as a coherent oscillation with complex propagation across the globe, modeled DCV lacks this structure altogether. Specifically, …
Lighting A Path To Biofouling Prevention: Investigating The Effect Of Ultraviolet Light On Biofouling, Cierra Rose Braga
Lighting A Path To Biofouling Prevention: Investigating The Effect Of Ultraviolet Light On Biofouling, Cierra Rose Braga
Theses and Dissertations
Ultraviolet light (UV) is considered an environmentally friendly antifouling method because it disrupts biological growth without the release of harmful toxins. The application of UV for the marine shipping industry is a relatively new concept, and there still remains many unknowns before it can be fully implemented. This research investigated several aspects of applying UVC for the control of fouling. A novel method of using embedded UV LEDs within a silicone coating for fouling control proved to be very effective at preventing fouling. The research also investigated the effect of using an external UVC light treatment to control fouling on …
Wind-Driven Setup, Roughness, And Drag Over A Depth- And Fetch-Limited Coastal Estuary, Jeffrey Allen Colvin
Wind-Driven Setup, Roughness, And Drag Over A Depth- And Fetch-Limited Coastal Estuary, Jeffrey Allen Colvin
Theses and Dissertations
The understanding of the momentum exchange across the air-sea interface is critical to accurately model and forecast wind speed, wave properties, setup, and circulation. This is particularly true for a restricted estuary, such as the Indian River Lagoon (IRL), where wind is the driving force behind water movement due to the limited number of direct ocean connections. Current atmospheric and hydrodynamic models use formulations of the drag coefficient and/or roughness length based on open ocean studies in which wave properties are not considered. This dissertation develops two parameterizations – one for wind setup and one for the drag coefficient – …
Longitudinal And Temporal Comparison Of Beach Sand On The Rio Grande Delta System, Samantha B. Moore
Longitudinal And Temporal Comparison Of Beach Sand On The Rio Grande Delta System, Samantha B. Moore
Theses and Dissertations
The Rio Grande is the 5th longest river in North America and defines a significant extent of the United States-Mexico border. It extends for 2830 km from its headwaters in the Rocky Mountains of Colorado to the Gulf of Mexico. The Rio Grande is fed by streams from the Sangre de Cristo Mountains, the Rio Conchos, the Pecos River, runoff from the Sacramento Mountains area, Devils River, the Rio Salado, and the Rio San Juan. This study addresses how the composition of sand forming the Rio Grande river delta into the Gulf of Mexico at Boca Chica Beach is changed …
Using Self-Organizing Maps As A Forecasting Tool, Andrea Honor
Using Self-Organizing Maps As A Forecasting Tool, Andrea Honor
Theses and Dissertations
Some extreme weather events, such as the early season heavy snow and cold weather outbreak of early November 2014, can be traced back to the influence of tropical or extratropical cyclones on the planetary scale flow. Such planetary scale reorganization also occurs in conjunction with serial extratropical cyclogenesis. Potential temperature on the dynamic tropopause (defined by the 2 PVU surface) allows for a dynamically compact characterization of the flow. NCEP Climate Forecast Systems Reanalysis data spanning 32 years are used to provide this measure, and Self-Organizing Maps (SOM) are then constructed to identify our atmospheric regimes. Key elements of this …
Developing A Probabilistic Heavy-Rainfall Guidance Forecast Model For Great Lakes Cities, Cory Kevin Rothstein
Developing A Probabilistic Heavy-Rainfall Guidance Forecast Model For Great Lakes Cities, Cory Kevin Rothstein
Theses and Dissertations
A method for predicting the probability of exceeding specific warm-season (April-October) 0-24 hour precipitation thresholds is developed based upon daily maximums of meteorological parameters. North American Regional Reanalysis and Daily Unified Precipitation data from 2002-2017 were used to gather meteorological data for the Milwaukee and Chicago County Warning Areas. Individual artificial neural networks and multiple logistic regressions were conducted for daily rainfall thresholds above 0.5'', 1'', 1.5'' and 2'' to determine the probability of threshold exceedances for each County Warning Area. The most important parameters were 1000-500 hPa specific humidity, vertical velocities at various levels, high cloud cover, precipitable water …
An Investigation Of The Conditional Practical Predictability Of The 31 May 2013 Heavy-Rain-Producing Mesoscale Convective System, Aidan Kuroski
An Investigation Of The Conditional Practical Predictability Of The 31 May 2013 Heavy-Rain-Producing Mesoscale Convective System, Aidan Kuroski
Theses and Dissertations
On 31 May 2013, strong thunderstorms initiated in west-central Oklahoma with one of the storms eventually creating a very strong tornado near El Reno, OK. The storms then grew upscale into a quasi-stationary mesoscale convective system that produced prolonged heavy rainfall that led to severe flooding across parts of Oklahoma, including the Oklahoma City metropolitan area. A 50-member ensemble of short range (0-24 h) forecasts was conducting using a set of initial conditions generated via cycled data assimilation to quantify event predictability and identify forecast sensitivities, primarily with CI and initial upscale growth. Both a composite and ensemble sensitivity analysis …
Using Advanced Post-Processing Methods With The Hrrr-Tle To Improve The Prediction Of Cold Season Precipitation Type, Timothy Thielke
Using Advanced Post-Processing Methods With The Hrrr-Tle To Improve The Prediction Of Cold Season Precipitation Type, Timothy Thielke
Theses and Dissertations
In this study we explore advanced statistical methods with the operational High-Resolution Rapid Refresh Model (HRRR) Time-Lagged Ensemble (TLE) to improve the prediction of cold season precipitation type. TLEs are a computationally efficient method to provide a slightly improved probabilistic forecast as the differences between model runs are an approximation of initial condition uncertainty. We apply evolutionary programming, weight-decay bias correction, and Bayesian Model Combination with fifteen HRRR forecast variables that potentially relate to precipitation type for station locations in the contiguous United States that are along and to the east of 100 W longitude to obtain probabilistic precipitation type …
Future Melting Away: Water Stress As A Threat To Human Security In Bangladesh And The Role Of International Community, Farzana Afroz Chowdhury
Future Melting Away: Water Stress As A Threat To Human Security In Bangladesh And The Role Of International Community, Farzana Afroz Chowdhury
Theses and Dissertations
Bangladesh is considered as one of the frontline states in the global climate change; its policy agendas attempt to respond to the perceived security threats emanating from such changes. Water stress is one of the key problems the country is facing. Yet, links between glaciers in the Hindu Kush Himalaya, Bangladesh’s climate, growing water stress, and its implications for human security have seldom been studied. Drawing on the concepts of climate change, human security and water stress, the thesis examines the causes of Bangladesh’s freshwater crisis and its contribution to the human insecurity. Here in this study, the influence of …
Isolating Secular Signals In Observations And Climate Model Simulations Using M-Ssa Based Wiener Filtering, Christian Grimm
Isolating Secular Signals In Observations And Climate Model Simulations Using M-Ssa Based Wiener Filtering, Christian Grimm
Theses and Dissertations
In this thesis, Wiener filtering of gridded surface-temperature time series from observations and climate model simulations is performed by using multi-channel singular spectrum analysis (M-SSA) in order to isolate non-stationary climate signals. The contributions to the singular spectrum from shorter-term internal climate variability, treated in this context as noise, are estimated by fitting to the data spatially extended stochastic models, which are subsequently used to produce synthetic ensembles of surface temperature time series and the corresponding synthetic M-SSA spectra. The full spectra are weighted by the signal-to-noise ratios and transformed back to physical space to obtain reconstructions of the non-stationary …
Invertebrate Paleoecology Of High Paleo-Latitude Carboniferous Strata Of The Tepuel-Genoa Basin, Argentina, Kate M. Gigstad
Invertebrate Paleoecology Of High Paleo-Latitude Carboniferous Strata Of The Tepuel-Genoa Basin, Argentina, Kate M. Gigstad
Theses and Dissertations
The Late Paleozoic Ice Age (LPIA), which began in the latest Devonian and ended in the Late Permian, was a time of active environmental changes. During this time, glaciers waxed and waned over the ancient continent of Gondwana that was situated over the southern pole. This time of transition from icehouse to greenhouse in the Permian is our closest analogue to our current environmental conditions and increased knowledge of our planetary past will greatly influence our future. Much of the previous research on marine invertebrate paleoecology during the LPIA occurs in far-field or low paleolatitude localities, but less is known …
Carbon Dynamics In Tropical Lake Malawi, Maxon Ngochera
Carbon Dynamics In Tropical Lake Malawi, Maxon Ngochera
Theses and Dissertations
Large lakes of the world play a vital role in the global carbon cycle as they act both as conduits and sinks of terrestrially and atmospherically derived carbon. Lake Malawi, lying at the extreme southernmost end of the East African Rift Valley is one of the largest, deepest and most ancient of the African Great Lakes. In this study, the spatial and seasonal variation of direct measurements of air and water pCO2 were taken for a period of one annual cycle using a vessel of opportunity along the north-south axis of Lake Malawi. These data, together with limnological and meteorological …
A Climatology Of Extreme South American Andean Cold Surges, Kevin Prince
A Climatology Of Extreme South American Andean Cold Surges, Kevin Prince
Theses and Dissertations
Interactions between the tropics and midlatitudes have been an ongoing area of research since the inception of meteorology. Cold surges represent one of several phenomena by which midlatitude features can modulate the atmosphere, both dynamically and thermodynamically, deep into the tropics. This study performs a climatology of particularly strong South American cold surges that follow along the Andes mountains to quantify the maximum extent to which these surges can modulate the atmosphere from the midlatitudes to the tropics. Data was collected for Austral winter (JJAS) from 1980-2010 (31 years). To identify events, standardized anomalies for 925 hPa meridional wind and …
Morphologic Evolution Of A Nearshore Berm: One Year Monitoring At Ft. Myers Beach, Florida, Kristopher Jason Enfinger
Morphologic Evolution Of A Nearshore Berm: One Year Monitoring At Ft. Myers Beach, Florida, Kristopher Jason Enfinger
Theses and Dissertations
Nourishment in the form of a nearhsore berm has become an important alternative method to protecting shorelines and introducing sediment back into the littoral system. In 2009, a nearshore berm was constructed at Ft. Myers Beach, Florida by the U.S. Army Corps of Engineers through maintenance dredging of a nearby navigational channel at Matanzas Pass. Constructed in the form of a nearshore bar, the berm was one of the shallowest placements in a low-wave energy setting. The Coastal Research Lab at the University of South Florida (USF-CRL) conducted field monitoring for the first four years after the construction. This project …
The Influence Of Vertical Advection Discretization In Wrf-Arw Model On Capping Inversion Representation In Warm-Season, Thunderstorm Supporting Environments, David Nevius
Theses and Dissertations
This study evaluates forecasts of capping inversions and thermodynamic variables for believed areas of possible deep, moist convection initiation during the warm-season using the Weather Research and Forecasting Model (WRF) with the Advanced Research core (WRF-ARW). WRF-ARW was configured nearly identical to the National Severe Storms Laboratory (NSSL) version of WRF (NSSL-WRF). WRF-ARW's default third-order-accurate vertical advection scheme, which is an odd-order-accurate scheme, is known to introduce implicit damping which acts to dampen short wavelength features (Skamarock et al. 2008), such as capping inversions. It is hypothesized that by increasing WRF-ARW's vertical advection to the next higher, even-order-accurate vertical advection …
A New Analysis Of The Gálvez-Davison Index For Convective Forecasts In Northern Africa, Gabriel D. Donndelinger
A New Analysis Of The Gálvez-Davison Index For Convective Forecasts In Northern Africa, Gabriel D. Donndelinger
Theses and Dissertations
Severe wind gusts and thunderstorms have been difficult to forecast in Africa. Traditional convective forecast tools (e.g. Total Totals Index, Lifted Index, K Index (KI) and Convective Available Potential Energy) do not accurately portray potential for thunderstorms in Africa. This research effort used the Gálvez-Davison Index (GDI), a convective index created for the tropics, and assess its applicability to northern Africa. GDI was produced for the Caribbean and Central America, and utilized temperature, moisture, mid-level stability, dry air entrainment and an elevation factor to calculate convective potential. In this research, GDI and KI were calculated using Global Forecast System (GFS) …
Impacts Of Sub-Auroral Polarization Streams On High Frequency Operations As A Function Of Modeled Particle Energy Flux, Nathan D. Smith
Impacts Of Sub-Auroral Polarization Streams On High Frequency Operations As A Function Of Modeled Particle Energy Flux, Nathan D. Smith
Theses and Dissertations
Space weather events can cause irregularities within the ionosphere; in particular, this research examines sub-auroral polarization streams (SAPS), as their accompanying irregularities and effects can degrade high-frequency (HF) signal propagation. It is known that the strongest westerly current drifts delineating SAPS are associated with a deep ionospheric trough, which in turn contaminates HF data with clutter from the non-standard ionosphere. Having a methodology to track and identify these occurrences on current computational architecture would provide operators enhanced situational awareness in knowing to expect degradation in HF processes. This study has discovered a weak, yet significant, exponentially decaying correlation between maximum …
The Geographic Distribution Of Downburst Frequency Across Spaceport Florida, Tania M. Garza
The Geographic Distribution Of Downburst Frequency Across Spaceport Florida, Tania M. Garza
Theses and Dissertations
Strong winds from downbursts pose a significant hazard to personnel and launch operations at Cape Canaveral Air Force Station (CCAFS) and NASA Kennedy Space Center (KSC). The CCAFS/KSC complex has a robust mesonet from which an 18 year (1995-2012) warm-season convective wind climatology (WSCWC) was developed (Koermer 2017). While the frequency of downbursts in the area has been determined, the frequency at the individual tower locations has not. The 5-minute peak wind data from the WSCWC was analyzed to determine the geographic distribution of downburst frequency across Spaceport Florida. For this project a downburst was determined by the threshold of …
Methodology To Analyze Tropical Cyclone Intensity From Microwave Imagery, Matthew W. Perkins
Methodology To Analyze Tropical Cyclone Intensity From Microwave Imagery, Matthew W. Perkins
Theses and Dissertations
Satellites with microwave remote sensing capabilities can be utilized to study atmospheric phenomena through high-level cloud cover (particularly cirrus), an advantage over visible and infrared bands, which only sense cloud tops. This unique capability makes microwave imagery ideal for studying the cloud structures of tropical cyclones (TCs) in detail, and relating these features to TC intensity. Techniques to estimate the intensity of TCs using infrared imagery, such as the Dvorak technique, have been used in TC forecasting for 40 years. However, due to the inherent temporal limitations of microwave imagery, no such similar technique exists for the microwave spectrum. This …
Evaluation Of A Cloud Detection Technique Using Spatial And Radiometric Thresholds For Near Infrared Satellite Imagery, William J. Graff
Evaluation Of A Cloud Detection Technique Using Spatial And Radiometric Thresholds For Near Infrared Satellite Imagery, William J. Graff
Theses and Dissertations
Knowledge of cloud location in near infrared (NIR) imagery is of interest to the meteorological community given the wavelengths greater spatial resolution compared to longwave infrared and its potential nighttime applications. This method consists of an algorithm that can be employed by multiple instrument platforms. It analyzes changes between satellite image radiances and a seasonal synthetic background radiance image. The NIR sensor bands of the Sentinel-2 Multispectral Instrument (MSI) and Suomi National Polar-Orbiting Partnership (Suomi NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) satellite instruments are used to evaluate the performance of a monochromatic change detection technique designed to locate areas …
Forecasting Lightning Initiation Utilizing Dual-Polarization Radar Parameters Over Washington, D.C., Sarah A. Olsen
Forecasting Lightning Initiation Utilizing Dual-Polarization Radar Parameters Over Washington, D.C., Sarah A. Olsen
Theses and Dissertations
Accurate forecasts of thunderstorms are vital to space launch, aviation, and public safety. Prior studies by Woodard (2011), Thurmond (2014), and Travis (2015) show that dual-polarization radar can be utilized to identify the presence of hydrometeors necessary for cloud charging. These studies emphasized that a combination of radar reflectivity (Z) and differential reflectivity (ZDR) predictors have the potential to improve forecast skill of lightning initiation over methods that rely on Z alone (Roeder and Pinder, 1998; Yang and King, 2010). Travis (2015) discovered two parameters, when used together, produced the best results: Z ≥ 36.5 dBZ and ZDR …
Forecasting Lightning Cessation Using Dual-Polarization Radar And Lightning Mapping Array Near Washington, D.C., Nancy M. Holden
Forecasting Lightning Cessation Using Dual-Polarization Radar And Lightning Mapping Array Near Washington, D.C., Nancy M. Holden
Theses and Dissertations
Accurate forecasts of thunderstorms are important to space launch, aviation, and public safety. While prior studies have primarily focused on atmospheric conditions leading to lightning onset, less research has been dedicated to the challenging problem of predicting lightning cessation. This study verifies the probabilistic lightning cessation model developed by Joseph Patton (2017) at Florida State University for use by the U.S. Air Force's 45th Weather Squadron at Cape Canaveral Air Force Station (CCAFS) and the National Aeronautics and Space Administration (NASA) Kennedy Space Center (KSC). The Washington, D.C. greater metropolitan area, which presents a climate different to that of central …
Evaluation Of A Climate Change Training Program For Local Government Employees, Clara Kashar
Evaluation Of A Climate Change Training Program For Local Government Employees, Clara Kashar
Theses and Dissertations
A local government in South Florida launched a training program to improve employee engagement on climate change using best practices in adult learning and climate communication to bridge the gap between climate science and action in government operations. The purpose of this program evaluation was to determine whether that climate change development and training program for local government employees met its stated goals and objectives. This evaluation blended a component of Stufflebeam’s Context, Input, Process, Product (CIPP) model with Kirpatrick’s Four Levels model. To conduct the evaluation, the researcher used a mixed methods approach for analyzing both quantitative and qualitative …