Oceanography and Atmospheric Sciences and Meteorology Commons^™

Investigating The Relationship Between Dissolved Oxygen And Nitrate Concentration As A Proxy For Marine Ecosystem Health, Natalia M. Moore

Theses and Dissertations

Coastal environments such as seagrass meadows span a wide range of spatial scales and can experience disturbances that cause rapid shifts to ecosystem dynamics. Increased pressure to the coastal zone has highlighted the need for constant, real-time monitoring to monitor current ecosystem status. A custom, low cost, high resolution, in situ sensor network was designed and tested in the Lower Laguna Madre, Texas to characterize primary productivity in seagrass meadows through gradient patterns of dissolved oxygen concentration, with the purpose of determining whether seagrass or phytoplankton were the more dominant primary producer. There was a distinct vertical and horizontal gradient …

Weather Parameters Influencing The Incidence Of Citrus Canker Caused By Aw Strain In The Rio Grande Valley, Amit Sharma

Theses and Dissertations

Citrus canker caused by bacterium Xanthomonas citri subsp. citri (Xcc) seriously affects the citrus industry by making the fruit unmarketable due to unsightly lesions on the fruit. Canker caused by Aw strain of Xcc was reported in the citrus trees located in the residential areas of the Rio Grande Valley (RGV). Canker severity differs amongst cultivars/varieties, and it is influenced by prevailing environmental conditions. Multiple regression modeling of the disease incidence with the environmental variables such as temperature, humidity, windspeed, wind gust, and rainfall was performed to understand the environmental conditions that are favorable for spread of citrus …

Understanding Ecological Relationships To Improve Biofouling Management Practices In The Marine Environment, Ann Catherine Wassick

Theses and Dissertations

Biofouling, the growth of benthic invertebrates on anthropogenic surfaces, impacts many industries and is a major vector of non-native species worldwide. Understanding the ecological relationships between biofouling organisms and their environment is necessary to assist management practices. This study investigates the biofouling communities at Port Canaveral, Florida, in order to potentially refine biofouling mitigation practices. Recruitment panels were used to document the temporal changes in community composition, biofouling pressure, recruitment, and growth rates. These factors were also used to assess relationships with temperature and salinity. A second component of this work provided documentation on the variation in non-native species abundance …

Modeling Settlement And Filtration Of The Indian River Lagoon Benthic Community, With An Emphasis On Living Dock Restoration Mats, Sandra Lisette Rech

Theses and Dissertations

The Indian River Lagoon (IRL) is one of the most biologically diverse estuaries in North America. An increase in population and anthropogenic effects have led to eutrophication, a decline in water quality, and overall degradation. The Living Docks program is a citizen science initiative started at the Florida Institute of Technology for lagoon restoration. In this program, public and private docks are volunteered to become Living Docks, where oyster mats made of plastic mesh and dead, dried oyster shells are attached to dock pilings in an effort to provide a natural substrate for benthic organism growth. The community which develops …

Tropical Cyclone And Ocean-Atmosphere Interactions In The Gulf Of Mexico, Emily Nichole Eley

Theses and Dissertations

The Gulf of Mexico (GoM) is historically a favorable region for the formation, maintenance and intensification of tropical cyclones that frequently evolve into powerful hurricanes. These natural disasters threaten the basin’s innate habitat and wildlife diversity, and the expansive coastal economies and communities. The dominant ocean circulation feature in the GoM is the Loop Current System (LCS) which includes the Loop Current (LC) and its associated mesoscale eddy field. The LC originates at the Yucatán Channel, loops anticyclonically into the basin, and ends at the Florida Straits; further it produces both anticyclonic and cyclonic eddies. The existence of the LCS …

Sources And Cycling Of Neodymium And Rare Earth Elements In The Arctic Amerasian Basin And Bering Sea, Brian D. Duggan

Theses and Dissertations

The isotopic composition of dissolved neodymium (¹⁴³Nd/¹⁴⁴Nd, expressed as εNd) behaves quasi-conservatively in the ocean and has been used as a palaeoceanographic tracer of ocean circulation. The εNd value of water masses is acquired—and often altered—during interaction with sediments along the margins; however, the processes involved in seawater εNd acquisition remains poorly characterized and quantified. Here we report the results of 349 Nd isotope and 354 rare earth element (REE) concentration measurements from 27 water column profiles across the Bering shelf and through the Arctic Amerasian Basin collected during U.S. Arctic GEOTRACES cruise HLY1502 (GEOTRACES section …

Arctic Ocean And Subarctic Seas Dynamics In A Changing Climate, Sarah B. Hall

Theses and Dissertations

Salinity is the primary determinant of the Arctic Ocean’s vertical density stratification in the upper ocean, which has major implications on the ocean’s physical dynamics alongside a period of rapidly declining sea ice. In recent decades, the Arctic’s freshwater content (FWC) has increased as a result of the accumulation of freshwater source inputs. Additional freshwater exported to the North Atlantic may hinder overturning processes that are vital to the regulation of global climate. This dissertation employs in situ measurements, satellite observations, and ocean model simulations to better understand salinity and freshwater changes in the Arctic Ocean during this changing climate. …

An Investigation Of Geostationary Satellite Imagery To Compare Developing And Non-Developing African Easterly Waves, Jenna Bartlett

Theses and Dissertations

African easterly waves (AEWs) are known precursors to tropical cyclone (TC) formation, although it is not always clear which AEWs will develop and which AEWs will not. To investigate AEW evolution, this study examines novel observations from the geostationary Advanced Baseline Imager (ABI) during July-September 2019. Case studies are conducted for two AEWs: one that became Hurricane Dorian, the strongest and most devastating hurricane of the 2019 Atlantic hurricane season, and a long-lived September AEW that did not become a TC. Lower-level moisture and flow, and the strength and spatial distribution of convective activity, differed between these two waves. By …

Defining Viable Solar Resource Locations In The Southeast United States Using The Satellite-Based Glass Product, Jolie Kavanagh

Theses and Dissertations

This research uses satellite data and the moment statistics to determine if solar farms can be placed in the Southeast US. From 2001-2019, the data are analyzed in reference to the Southwest US, where solar farms are located. The clean energy need is becoming more common; therefore, more locations than arid environments must be observed. The Southeast US is the main location of interest due to the warm, moist environment throughout the year. This research uses the Global Land Surface Satellite (GLASS) photosynthetically active radiation product (PAR) to determine viable locations for solar panels. A probability density function (PDF) along …

The Effects Of Incorporating 0-500 M Srh Into The Violent Tornado Parameter, Jay Palmer Roberts

Theses and Dissertations

Between 2011-2021, violent tornadoes accounted for an average of 65% of all tornado-related fatalities. The Violent Tornado Parameter (VTP), created in 2018, attempts to address this forecast problem but has issues with false alarms. Storm Relative Helicity has historically been used in tornado forecasting. Recent studies have shown the 0-500 m effective layer SRH (ESRH) has skill in discerning significantly tornadic events from those that are not.

This study explored the effects of incorporating 0-500 m ESRH into the VTP and issues relating to the parameter’s false alarm rate by examining RUC/RAP forecast soundings for 302 U.S. tornadic events (83 …

Fish Community Analysis Using Multidirectional Rov Video Surveys In The Northwestern Gulf Of Mexico, Keegan J. Angerer

Theses and Dissertations

In this study, ROV surveys with multidirectional video were used to analyze the fish communities associated with artificial reef patches in the Rio Grande Valley artificial reef 13.7 km off the coast of South Padre Island, TX. Nine configurations of reef patches consisting of varying combinations and densities of concrete pyramid and low-profile modules were surveyed. The highest species diversity was found at patches with large deployments of both pyramids and low-profile modules. Total Red Snapper Lutjanus campechanus abundance did not differ between configurations, but the highest abundances of juvenile Red Snapper were found at configurations with one pyramid and …

Red Drum (Sciaenops Ocellatus) Trophic Web Reconstruction Using Stable Isotopes In Two Systems In The Northwestern Gulf Of Mexico, Elizabeth Mogus Garcia

Theses and Dissertations

Estuaries act as nurseries for many important fishes, including predators like Red Drum (Sciaenops ocellatus). Using gut content and stable isotope analyses to better understand juvenile S. ocellatus’ diet and role within the trophic web, a full year of data was collected on a quarterly basis to illustrate a change in diet based on resource availability at two study sites and for two non-overlapping S. ocellatus sizes. Panopeidae and Penaeidae were the most abundant prey items found in S. ocellatus stomachs for both sizes, sites, and four quarters representing over 50% of the diet. Stable isotope analyses …

Growth And Reproduction In Gulf Of Mexico Black Corals (Antipatharians) In Field And Laboratory Studies, Victoria E. Salinas

Theses and Dissertations

Black corals provide an important ecosystem of marine life and are found throughout all the oceans of the world at depths between 2 and 8,600 m. However, little is understood about their life history and the factors that control the distribution of black corals, particularly in the Gulf of Mexico (GoM). Given the impacts of the Deepwater Horizon oil spill on soft corals (e.g., black corals and octocorals) in the GoM, studies of their growth and reproductive biology in both natural and aquaculture environments are crucial for restoration efforts. The objectives of this study were to examine reproductive processes, compare …

Network Analysis Of Scientific Research In The Gulf Of Mexico, Juliet S. Vallejo

Theses and Dissertations

The Gulf of Mexico ecosystem represents a significant management challenge in its 3,423-mile coastline and transnational regulatory setting, along five states from the United States, six states from Mexico, and Cuba which borders the southeastern quadrant. Providing various resources to the regional economies, the continued success of these resources depends on the collaboration among transnational participants in bringing together complementary skills and multidisciplinary approaches to producing, circulating, and utilizing scientific knowledge. Using bibliometric analysis of Gulf of Mexico-related published research over 18 years from 2000 to 2018 allows for identifying organizations, their connections, and trends in the production of scientific …

Water Quality Correlations With Phytoplankton Community Composition In A Polluted Shallow Subtropical Estuary, Connor Joseph Wong

Theses and Dissertations

The Indian River Lagoon (IRL) estuary has experienced eutrophication and degraded water quality due to high nutrient input, urbanization, and anthropogenic stressors. High nutrient input and restricted estuarine hydrology promotes algal blooms. Algal blooms or harmful algal blooms (HABs) are a global concern as they can cause negative ecological and economic impacts. The frequency and range of HABs is expected to be exacerbated by climate change and altered oceanic and estuarine conditions. Research on the formation and frequency of HABs is an ongoing global effort, but algal blooms are often dynamic and patchy making them difficult to study. This study …

Effects Of Nutrient Enrichment On Mangrove And Saltmarsh Habitats, Elena A. Flores

Theses and Dissertations

Nutrient over-enrichment is a global threat to coastal and marine environments. Yet, system-specific attributes of estuarine and coastal ecosystems may result in large differences in their sensitivity and susceptibility to such threat. In tropical latitudes, plant species adapted to low-nutrient habitats generally have nutrient-conservation mechanisms that acquire, use, and internally recycle nutrients efficiently. Thus, a major challenge for managers and decision makers is to develop a predictive and holistic understanding of how nutrient loading alters ecosystem functions and therefore ecosystem services. The objective of the present research is to document short and long-term effects of persistent nutrient …

Analyzing The Impact Of Governance Strategies On Trust And Risk In The Salish Sea Transboundary Fishery Context, Evelyn Roozee

Theses and Dissertations

The Salish Sea is the site of a transboundary fishery whose coastal jurisdiction includes British Columbia, Washington State, the two federal governments, and many Indigenous tribes with sovereign rights. Fishery management becomes increasingly complex when transboundary cooperation is needed. Furthermore, while the Salish Sea region has attempted to facilitate better transboundary collaborative governance, these have generally failed to institutionalize the principles of adaptive management. This research seeks to assess current trust and risk perceptions and analyze the effects of control mechanisms used in the transboundary fishery management network. The data consists of a survey measuring collaborative precursors, barriers, and outcomes …

Exploring The Impact Of End-User Engagement On The Diffusion And Adoption Of A Climate Resilience Tool In The Gulf Of Mexico, Renee C. Collini

Theses and Dissertations

Climate change-related hazards negatively impact ecosystems, economies, and quality of life. Significant resources have been invested in data collection and research with the goal of enhanced understanding and capacity to predict future conditions in order to mitigate or adapt to intensifying hazard risk. The expansive production of climate science has generated a necessary complimentary enterprise dedicated to enhancing decision-makers’ understanding of and access to climate science as it is essential for future societal and ecological well-being. Though the aim of these many tools is to support resilient decision-making in the face of climate change, professionals report an underutilization of climate …

An Investigation Of Sea-Breeze Driven Convection Along The Northern Gulf Coast, Caitlin Ford

Theses and Dissertations

Although sea-breezes frequently initiate convection, it is oftentimes challenging to forecast the precise location of storm development. This research examines temporal and spatial characteristics of sea-breeze driven convection and environmental conditions that support convective or non-convective sea-breeze days along the Northern Gulf Coast. Base reflectivity products were used to identify the initial time of convection (values greater than 30 dBZs) along the sea-breeze front. It was found that convective sea-breezes initiated earlier in the day compared to non-convective sea-breezes. Mapping convective cells in ArcGIS revealed favored locations of thunderstorm development including the southeastern cusp of Mobile County, Alabama and convex …

Against The Clock: Uncovering Diurnal Time Interval Decision Differences During Tornado Warnings For Lower Mississippi Valley Residents, Stephen Holden Wooten

Theses and Dissertations

With a higher number of nocturnal tornado events, I surveyed residents of Alabama, Arkansas, Kentucky, Mississippi, and Tennessee (N = 487 for each sample) to determine the time, in minutes, it took to reach a decision on shelter-seeking. I utilized latent class analysis (LCA) to create class memberships, based on diurnal and nocturnal scenarios, to associate with time intervals. Four actors were identified for each scenario: Tech Users, Typical Actors, Non-Reactors, and Social Actors for the day sample, Tech Users, Typical Actors, Passive Actors, and Non-Reactors for the night sample. Time intervals were created and applied to each class. All …

Impact Of Climate Oscillations/Indices On Hydrological Variables In The Mississippi River Valley Alluvial Aquifer., Meena Raju

Theses and Dissertations

The Mississippi River Valley Alluvial Aquifer (MRVAA) is one of the most productive agricultural regions in the United States. The main objectives of this research are to identify long term trends and change points in hydrological variables (streamflow and rainfall), to assess the relationship between hydrological variables, and to evaluate the influence of global climate indices on hydrological variables. Non-parametric tests, MMK and Pettitt’s tests were used to analyze trend and change points. PCC and Streamflow elasticity analysis were used to analyze the relationship between streamflow and rainfall and the sensitivity of streamflow to rainfall changes. PCC and MLR analysis …

Use Of Consumer Grade Small Unmanned Aerial Systems (Suas) For Mapping Storm Damage In Forested Environments, James Dewey Cox

Theses and Dissertations

Storm damages to forested environments pose significant challenges to landowners, land managers, and conservationists alike. Damage scope and scale assessments can be difficult, costly, and time consuming with conventional pedestrian survey techniques. Consumer grade sUAS technology offers an efficient, cost-effective way to accurately assess storm damage in small to moderate sized survey areas (less than 10 km²). Data were collected over a 0.195 km² area of damaged timber within the Kisatchie National Forest in Central Louisiana using a DJI Mavic 2 Pro drone. Collected imagery was processed into an orthomosaic using Agisoft Metashape Professional with a resulting ground sampling distance …

Testing The Efficacy Of Uvc Leds For Biofouling Control, Margaret Jeannette Giggie

Theses and Dissertations

The use of ultraviolet-C (UVC) light as a biofouling preventative has been successfully demonstrated using mercury-based lamps. However, these lamps have several limitations (such as fragility and use of mercury), and the use of UVC LEDs (light-emitting diodes) has been suggested as an alternative. Several experiments were conducted to assess the efficacy of LED strips (29 W, 270 nm, emittance angle of 130º) for biofouling control, as well as to compare them to a classic lamp (25 W, 254 nm, emits UVC light at 360º). Experiment #1 assessed the biofouling abundance and community composition on test panels exposed to either …

Burn Probability And Climate Change: A Quantitative Evaluation Of The Temporal Alterations Of Wildfire, David N. Robinson

Theses and Dissertations

The intensity of extreme weather events, specifically wildfires, along the West Coast has slowly grown overtime due to atmospheric changes caused by climate change. The Air Force, though aware of the threat that is wildfire, does not currently have a quantitative way to assess the hazard to base locations. In this paper, burn probability is quantitatively calculated through the geospatial analysis programs to provide a means of assessing wildfire vulnerability. The FlamMap fire simulator generated burn probabilities for Vandenberg Air Force Base using climate data generated by the remote automated weather station on the base to highlight how the burn …

Intercomparison Of Four Microphysics Schemes In Simulating Persistent Arctic Mixed-Phase Stratocumulus Clouds, Zachary A. Cleveland

Theses and Dissertations

Persistent Arctic mixed-phase stratocumulus clouds (AMPS) are important to the surface radiation budget of the Arctic. Their presence produces warming within the boundary layer and at the surface and inaccurately forecasting AMPS can lead to large, erroneous temperature forecasts. A Large Eddy Simulation of a case study of a persistent AMPS cloud was conducted using the Advanced Research Weather Research and Forecasting (WRF-ARW) model. The case examined occurred near Oliktok Point, AK between 26 and 27 April, 2017. The produced cloud pattern and properties of four different microphysics schemes -- P3, Thompson, Morrison, and WSM6 -- are compared to observations. …

Applications Of A Lightning Proxy To Generate Synthetic Lightning For Use In Physics-Based Image-Chain Models, Bryan G. Castro

Theses and Dissertations

A method of generating synthetic lightning through the use of a convective available potential energy (CAPE) times precipitation rate (P) proxy is applied over three distinct climatological zones of the world for a single warm season: central and southern AZ of the United States, central Cuba, and North Korea. Global Forecast System (GFS) 0.25° by 0.25° forecast data for June, July, and August of 2019 is used to provide 6-hourly CAPE and precipitation rate, while Global Lightning Dataset (GLD360) data for the period 2016 to 2020 is used to provide observed lightning strokes. A five-year lightning climatology study is conducted …

Global Sporadic-E Climatological Analysis Using Gps Radio Occultation And Ionosonde Data, Travis J. Hodos

Theses and Dissertations

A climatology of sporadic-E (Es) derived from a combined data set of GPS radio occultation (GPS-RO) and ground-based ionosonde soundings is presented for the period from September 2006 to February 2019. The ionosonde soundings were measured using the Lowell Digisonde International (LDI) Global Ionosphere Radio Observatory (GIRO) network consisting of 65 sites and 13,141,060 total soundings. The GPS-RO observations were taken aboard the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) satellites and processed using two binary Es detection algorithms, totaling 9,072,922 occultations. The first algorithm is an S4 amplitude threshold calibrated to the occurrence of any blanketing Es …

A Framework For Assessing Facility-Level Vulnerability And Risk To Extreme Weather Events, Blake A. Gawlik

Theses and Dissertations

Intensifying extreme weather events, tied to the rise in the global average temperature, put global built infrastructure at risk. This presents a daunting challenge for organizational leaders who are tasked to determine how best to adapt current infrastructure to uncertain future events. To develop adaptation plans and policies, vulnerability and risk must be downscaled to an actionable scale, such that planners, designers, and engineers can make adaptation recommendations. However, previous research has largely assessed risk at coarser scales, e.g., regional, national, or global. These assessments are informative, but do not help those tasked to lead adaptation to make detailed, actionable …

A Critical Review Of Climate Change On Coastal Infrastructure Systems, Gregory J. Howland Jr.

Theses and Dissertations

This thesis is a response to climate threats identified by DoD report on Climate Change in 2019. A critical review of climate change literature related to coastal infrastructure was conducted to synthesize past research and to inform future research. This review intends to inform how climate change may impact infrastructure systems, how those impacts are evaluated, can the investigation be improved, and what can stakeholders learn from the outcomes. The end goal is to find climate change mitigation strategies and adaptation measures, or identify the easiest path to get to that end. The compiled information will inform civilian and military …

Carbon Estimation And Decision Making In Usaf Acquisition, Robert F. Gray

Theses and Dissertations

Recent executive orders and international agreements require the United States to significantly reduce its carbon and greenhouse gas emissions. The DoD is a significant contributor to the carbon emissions of the USA and will be required to reduce the emissions. Therefore, in order to make appropriate programmatic decisions the DoD needs to develop an appropriate method for estimating carbon and making programmatic decisions; trading-off carbon emissions with the traditional cost-schedule-performance metrics. This thesis examines the possibility of developing a model that can be used to estimate the carbon footprint of producing a system before detailed engineering designed have been complete.