Oceanography and Atmospheric Sciences and Meteorology Commons^™

Assessing Long-Term Coral Coverage At East And West Flower Garden Banks, Rebekah Alicia Hernandez

Theses and Dissertations

Coral reefs provide critical habitat for diverse benthic communities; however, more than 10% of existing reefs have been lost as a result of natural and anthropogenic stressors. While there has been a decline in reefs around the world, East and West Flower Garden Banks (FGBs), part of Flower Garden Banks National Marine Sanctuary (FGBNMS), have maintained > 50% live coral cover for over 27 years as revealed by the FGBNMS long-term monitoring (LTM) program. In the 1980’s, the LTM program at East and West FGBs was developed in response to the expansion of oil and gas exploration, anchoring, and fishing impacts …

Biochar Applications To The Remediation Of Lead And Polychlorinated Biphenyl Contaminated Water, Victory Itua Igberase

Theses and Dissertations

This study investigated the performance of biochar materials as adsorbents to remove Pb and polychlorinated biphenyl (PCB) in aqueous solutions. Batch adsorption and column experiment packed with biochar and geomaterials (pumice) in 1:1 volume ratio was evaluated to address the efficacy of biochar in removing Pb while only batch adsorption was employed for PCB removal with biochar materials. Overall, PT biochars performed the best (42–53 mg g−1) followed by BE biochars (10–32 mg g−1) and AB biochars (17–27 mg g−1) while high temperature biochars were favored in terms of maximum Pb adsorption capacity. Column Pb breakthrough showed similar results, with …

A Typology Of Drought Decision Making: Synthesizing Across Cases To Understand Drought Preparedness And Response Actions, Amanda E. Cravens, Jen Henderson, Jack Friedman, Nina Burkardt, Ashley E. Cooper, Tonya Haigh, Michael Hayes, Jamie Mcenvoy, Stephanie Paladino, Adam K. Wilke, Hailey Wilmer

National Drought Mitigation Center: Faculty Publications

Drought is an inescapable reality in many regions, including much of the western United States. With climate change, droughts are predicted to intensify and occur more frequently, making the imperative for drought management even greater. Many diverse actors – including private landowners, business owners, scientists, non-governmental organizations (NGOs), and managers and policymakers within tribal, local, state, and federal government agencies – play multiple, often overlapping roles in preparing for and responding to drought. Managing water is, of course, one of the most important roles that humans play in both mitigating and responding to droughts; but, focusing only on “water managers” …

Novel Application Of 210po-210pb Disequilibria To Date Snow, Melt Pond, Ice Core, And Ice-Rafted Sediments In The Arctic Ocean, Mark Baskaran, Katherine Krupp, Mark Baskaran

Environmental Science and Geology Faculty Research Publications

We collected surface ocean water, snow, grab ice, ice core, melt pond and ice-rafted sediment (IRS) from 5 ice stations during the Western Arctic US GEOTRACES cruise (USGCG Healy; August 10 – October 7, 2015) and analyzed for 210Po (T1/2 = 138.4 days) and 210Pb (T1/2 = 22.3 years) in dissolved and particulate phases (snow, grab ice, ice core, surface seawater) to investigate the 210Po:210Pb disequilibria in these matrices. Thirteen aerosol samples, using a large-volume aerosol sampler (PM10), from Dutch Harbor, AK to North Pole, were also collected and analyzed for 210Po/210Pb to quantify the atmospheric depositional input to the …

Phragmites Australis Dieback In The Mississippi River Delta: Chemical Profiles Of Soil Types And Restoration Potential, Herie Lee

LSU Master's Theses

Since 2016, there has been widespread dieback of P. australis in the Lower Mississippi River Delta (hereafter referred to as Lower MRD, which is defined as the Birds Foot Delta) with relatively little to no signs of recovery. The cause of the current dieback is not fully understood. This thesis explores P. australis with emphasis on chemical profile characterization of different soil types and its effects on plant growth and the potential for restoration in the Lower MRD.

In chapter 2, I characterized the chemical profiles of soils collected from healthy and dieback stands of Phragmites, and from newly …

210po And 210pb As Tracers Of Particle Cycling And Export In The Western Arctic Ocean, Wokil Bam, Kanchan Maiti

Environmental Science and Geology Faculty Research Publications

The distribution and vertical fluxes of particulate organic carbon and other key elements in the Arctic Ocean are primarily governed by the spatial and seasonal changes in primary productivity, areal extent of ice cover, and lateral exchange between the shelves and interior basins. The Arctic Ocean has undergone rapid increase in primary productivity and drastic decrease in the areal extent of seasonal sea ice in the last two decades. These changes can greatly influence the biological pump as well as associated carbon export and key element fluxes. Here, we report the export of particulate organic and inorganic carbon, particulate nitrogen …

U.S. Geological Survey Science For The Wyoming Landscape Conservation Initiative—2018 Annual Report, Patrick J. Anderson, Cameron L. Aldridge, Jason S. Alexander, Timothy J.` Assal, Steven Aulenbach, Zachary H. Bowen, Anna D. Chalfoun, Geneva W. Chong, Holly Copeland, David R. Edmunds, Steve Germaine, Tabitha Graves, Julie A. Heinrichs, Collin G. Homer, Christopher G. Huber, Aaron N. Johnston, Matthew J. Kauffman, Daniel J. Manier, Ryan R. Mcshane, Cheryl A. Eddy-Miller, Kirk A. Miller, Adrian P. Monroe, Michael S. O'Donnell, Anna Ortega, Annika W. Walters, Daniel J. Wieferich, Teal B. Wyckoff, Linda Zeigenfuss

United States Geological Survey: Water Reports and Publications

The Wyoming Landscape Conservation Initiative (WLCI) was established in 2007 as a collaborative interagency partnership to develop and implement science-based conservation actions. During the past 11 years, partners from U.S. Geological Survey (USGS), State and Federal land management agencies, universities, and the public have collaborated to implement a long-term (more than 10 years) science-based program that assesses and enhances the quality and quantity of wildlife habitats in the southwest Wyoming region while facilitating responsible development. The USGS WLCI Science Team completes scientific research and develops tools that inform and support WLCI partner planning, decision making, and on-the-ground management actions.

In …

Simulating Cambrian Climate: The Significance Of Atmospheric Co2 Concentration And Continental Position, Grace Cutting

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

The Cambrian Period began approximately 541 million years ago, and is known for the “Cambrian Explosion”, a time when multicellular life began to rapidly diversify. There is natural historic evidence (isotopes, rock formations, and fossils) that suggests the Cambrian Period experienced a warm climate. However, there is also conflicting evidence that the Cambrian climate may have undergone freezing and thawing cycles, with ice possibly present near the equator. It is critical to understand how ecosystems were able to adapt to past climate changes, especially when analyzing the impacts of modern human activity on climate. Climate model simulations were run to …

An Integrative Model For Soil Biogeochemistry And Methane Processes: I. Model Structure And Sensitivity Analysis, Daniel M. Ricciuto, Xiaofeng Xu, Xiaoying Shi, Yihui Wang, Xia Song, Christopher W. Schadt, Natalie A. Griffiths, Jiafu Mao, Jeffrey M. Warren, Peter E. Thornton, Jeff Chanton, Jason K. Keller, Scott D. Bridgham, Jessica Gutknecht, Stephen D. Sebestyen, Adrien Finzi, Randall Kolka, Paul J. Hanson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Environmental changes are anticipated to generate substantial impacts on carbon cycling in peatlands, affecting terrestrial-climate feedbacks. Understanding how peatland methane (CH₄) fluxes respond to these changing environments is critical for predicting the magnitude of feedbacks from peatlands to global climate change. To improve predictions of CH₄ fluxes in response to changes such as elevated atmospheric CO₂ concentrations and warming, it is essential for Earth system models to include increased realism to simulate CH₄ processes in a more mechanistic way. To address this need, we incorporated a new microbial-functional group-based CH₄ module into the Energy …

Codar's Surface Flow At The Mouth Of The Chesapeake Bay: Relation To Bay's And Atlantic's Forcing, Shelby Kathryn Henderson

OES Theses and Dissertations

Surface currents in the lower Chesapeake Bay (CB) observed with land-based high-frequency radar antennas, or Coastal Ocean Dynamics Application Radar (CODAR), produce hourly 2D maps of current velocities used for search and rescue, pollution tracking, and fishing operations. This study analyzes the correlations between a 9-year record of surface currents measured by CODAR to coastal sea level, local wind forcing, river discharge into CB, and water transport through the Florida Straits, representing the Gulf Stream’s control on sea level along the U.S. mid-Atlantic coast. The goal of this study is to find ways to use CODAR data to detect and …

Droughtscape, Summer 2021, National Drought Mitigation Center

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

DroughtScape, Summer 2021

Geological Structures And Crustal Architecture Of The Cascadia Subduction Zone From The Integration Of Multiple Geophysical Datasets, Asif Ashraf

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

The Cascadia subduction zone (CSZ) has a high potential for an inevitable and devastating megathrust earthquake. This margin is characterized by a complex seismicity pattern. Particularly in Oregon, there is a seismically quiescent zone bounded by high seismicity regions to the north and south. To comprehend these variations in seismicity, it is important to study the differences in crustal architectures and physical properties (densities and magnetic susceptibilities) along the CSZ. The primary objectives are to develop two plate-scale 2D integrated models through different seismicity zones and to map major tectonic structures from filtered potential fields. The Juan de Fuca oceanic …

Modeling And Measuring Water Level Fluctuations In The Greenland Ice Sheet: How Moulin Life Cycle And Shape Can Inform Us On The Subglacial Drainage System., Celia Trunz

Graduate Theses and Dissertations

In the ablation zone of land terminating sectors of the Greenland Ice Sheet (GrIS), water pressures at the bed control ice motion variability on diurnal and seasonal timescales. During the melt season, large volumes of surface meltwater access the ice-bed interface through moulins.Moulins are large vertical shafts that connect the supraglacial and subglacial drainage systems. Moulins form when a crevasse intersects a surface meltwater source that can drive hydrofracture to the bed of the ice sheet. Upon reaching the bed, meltwater can establish and sustain an efficient, channelized drainage system. Due to the technical impossibility of physically exploring underwater passages …

Archaeology And Seasonality Of Stock Island (8mo2), A Glades-Tradition Village On Key West, Ryan M. Harke

USF Tampa Graduate Theses and Dissertations

Later Glades-period cultures (ca. 500–1760 CE) of south Florida and the Florida Keys are understudied and thus poorly understood, especially those that pre-date the arrival of Spaniards to the New World. Recent archaeological models of their sociopolitical organization suggest that by the Glades I-II transition (750/800 CE), south Florida peoples were organized into what appear to be regional population centers (e.g., Pineland and Mound Key, Granada, Turner River) and smaller hinterland towns in the Everglades (e.g., Cane Patch, Bear Lake) and the Florida Keys (e.g., Stock Island, Clupper Site). Smaller towns are hypothesized to be sedentary, heterarchically-organized, simple chiefdoms from …

Radioisotope Constraints Of Arctic Deep Water Export To The North Atlantic, Lauren Kipp, Jerry F. Manus, Markus Kienast

School of Earth & Environment Departmental Research

The export of deep water from the Arctic to the Atlantic contributes to the formation of North Atlantic Deep Water, a crucial component of global ocean circulation. Records of protactinium-231 (231Pa) and thorium-230 (230Th) in Arctic sediments can provide a measure of this export, but well-constrained sedimentary budgets of these isotopes have been difficult to achieve in the Arctic Ocean. Previous studies revealed a deficit of 231Pa in central Arctic sediments, implying that some 231Pa is either transported to the margins, where it may be removed in areas of higher particle flux, or exported from the Arctic via deep water …

Development Of A Flash Drought Intensity Index, Jason A. Otkin, Yafang Zhong, Eric D. Hunt, Jordan I. Christian, Jeffrey B. Basara, Hanh Nguyen, Matthew C. Wheeler, Trent W. Ford, Andrew Hoell, Mark Svoboda, Martha C. Anderson

National Drought Mitigation Center: Faculty Publications

Flash droughts are characterized by a period of rapid intensification over sub-seasonal time scales that culminates in the rapid emergence of new or worsening drought impacts. This study presents a new flash drought intensity index (FDII) that accounts for both the unusually rapid rate of drought intensification and its resultant severity. The FDII framework advances our ability to characterize flash drought because it provides a more complete measure of flash drought intensity than existing classification methods that only consider the rate of intensification. The FDII is computed using two terms measuring the maximum rate of intensification (FD_INT) and average drought …

Water Quality Threats, Perceptions Of Climate Change And Behavioral Responses Among Farmers In The Ethiopian Rift Valley, Tewodros R. Godebo, Marc A. Jeuland, Christopher J. Paul, Dagnachew L. Belachew, Peter G. Mccornick

National Drought Mitigation Center: Faculty Publications

This work aims to assess water quality for irrigated agriculture, alongside perceptions and adaptations of farmers to climate change in the Main Ethiopian Rift (MER). Climate change is expected to cause a rise in temperature and variability in rainfall in the region, reducing surface water availability and raising dependence on groundwater. The study data come from surveys with 147 farmers living in the Ziway–Shala basin and water quality assessments of 162 samples from groundwater wells and surface water. Most groundwater samples were found to be unsuitable for long term agricultural use due to their high salinity and sodium adsorption ratio, …

Biotransformation Of Doxycycline By Brevundimonas Naejangsanensis And Sphingobacterium Mizutaii Strains, Ting He, Jianguo Bao, Yifei Leng, Daniel D. Snow, Shuqiong Kong, Tong Wang, Xu Li

Nebraska Water Center: Faculty Publications

The fate of doxycycline (DC), a second generation tetracycline antibiotic, in the environment has drawn increasing attention in recent years due to its wide usage. Little is known about the biodegradability of DC in the environment. The objective of this study was to characterize the biotransformation of DC by pure bacterial strains with respect to reaction kinetics under different environmental conditions and biotransformation products. Two bacterial strains, Brevundimonas naejangsanensis DD1 and Sphingobacterium mizutaii DD2, were isolated from chicken litter and characterized for their biotransformation capability of DC. Results show both strains rely on cometabolism to biotransform DC with tryptone as …

Drone-Based Magnetic Surveying In Eastern Nebraska, Sulaiman Albadi

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

A magnetic survey is one of the methods used by scientists to detect subsurface features. Magnetic surveys can be carried out by walking on the surface of the earth with a magnetic field reading device called a magnetometer. Alternatively, a magnetometer can be installed on a moving platform (aircraft, boat, drone, bicycle) to conduct a more efficient magnetic survey. The geophysics team at the University of Nebraska at Lincoln assembled a drone-based magnetic survey system in 2019 (Jacobson and Filina, 2019) that has proven effective in magnetic readings over the Northern Bounding Fault (NBF) in eastern Nebraska (Jacobson and Filina, …

Past Ice-Ocean Interactions On The Sabrina Coast Shelf, East Antarctica: Deglacial To Recent Paleoenvironmental Insights From Marine Sediments, Kara J. Vadman

USF Tampa Graduate Theses and Dissertations

The East Antarctic Ice Sheet (EAIS) contains ~53 meters of sea level equivalent (SLE) ice, and observations suggest it is sensitive to ongoing and past climate change. The EAIS has traditionally been considered insensitive to climate perturbations because it is largely grounded above sea level. However, aerogeophysical surveys, oceanographic observations, and models indicate that large areas of the EAIS are grounded below sea level and contain 19.2 m SLE. Marine-based parts of the EAIS are thought to be located on inland-sloping beds that drain through marine terminating outlet glaciers, indicating large areas of the EAIS may be more sensitive to …

Characterizing The Northern Hemisphere Circumpolar Vortex Through Space And Time, Nazla Bushra

LSU Doctoral Dissertations

This hemispheric-scale, steering atmospheric circulation represented by the circumpolar vortices (CPVs) are the middle- and upper-tropospheric wind belts circumnavigating the poles. Variability in the CPV area, shape, and position are important topics in geoenvironmental sciences because of the many links to environmental features. However, a means of characterizing the CPV has remained elusive. The goal of this research is to (i) identify the Northern Hemisphere CPV (NHCPV) and its morphometric characteristics, (ii) understand the daily characteristics of NHCPV area and circularity over time, (iii) identify and analyze spatiotemporal variability in the NHCPV’s centroid, and (iv) analyze how CPV features relate …

Hydrometeorological Responses To Abrupt Land Surface Change Following Hurricane Michael, Shannon Alexis Nelson

LSU Master's Theses

While many of the destructive environmental conditions associated with tropical cyclones are well recognized, tropical cyclone-induced defoliation, a reduction in green leaves and mature vegetation, has been largely overlooked as a source of environmental stress following tropical cyclone passage. The land surface change associated with defoliation reduces evapotranspiration and shade, thus altering boundary layer moisture and energy fluxes that drive the local water cycle, for many months after tropical cyclone passage. Understanding the potential for any hydrometeorological impacts arising from such abrupt land surface change is important for guiding future post-hurricane preparedness and recovery planning in coastal communities.

This thesis …

Changes In Tropospheric Ozone Associated With Strong Earthquakes And Possible Mechanism, Feng Jing, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The index of ozone anomaly (IOA) has been proposed to detect changes in tropospheric ozone associated with strong earthquakes. The tropospheric ozone prior and after the 2008 Wenchuan earthquake has been analyzed using IOA. Atmospheric infrared sounder ozone volume mixing ratio (O3 VMR) at different pressure levels (600, 500, 400, 300, 200 hPa) for an 18-year period 2003–2020 has been considered to identify the unique behavior associated with the strong earthquakes. Our results show distinct enhancement in tropospheric ozone occurred 5 d (7 May 2008) prior to the main event and distributed along the Longmenshan fault zone. An enhancement in …

Linking Human Activities To Water Quality In Coastal New England: Past And Present, Amelia Hurst

University Scholar Projects

This project examines the timing and effect of direct and indirect anthropogenic and natural influences on the marine environment in embayments in southern New England over the past decades to century timescale. We investigated the effects of human land use from colonial through post-industrial times, determined baseline conditions and natural climatic variability, and analyzed the response of marine ecosystems to specific local management actions aimed to improve water quality. A coastal sediment core was taken in Mumford Cove, CT and was analyzed downcore for eutrophication markers (C: N, %C, %N, d¹⁵N, d¹³C) and metals (Hg, Pb, …

Multi-Dimensional Drought Assessment In Abbay/Upper Blue Nile Basin: The Importance Of Shared Management And Regional Coordination Efforts For Mitigation, Yared Bayissa, Semu Moges, Assefa Melesse, Tsegaye Tadesse, Anteneh Z. Abiy, Abeyou Worqlul

National Drought Mitigation Center: Faculty Publications

Drought is one of the least understood and complex natural hazards often characterized by a significant decrease in water availability for a prolonged period. It can be manifested in one or more forms as meteorological, agricultural, hydrological, and/or socio-economic drought. The overarching objective of this study is to demonstrate and characterize the different forms of droughts and to assess the multidimensional nature of drought in the Abbay/ Upper Blue Nile River (UBN) basin and its national and regional scale implications. In this study, multiple drought indices derived from in situ and earth observation-based hydro-climatic variables were used. The meteorological drought …

Climatic And Topographic Control Of The Stable Isotope Values Of Rivers On The South Island Of New Zealand, Matthew S. Lachniet, Christopher M. Moy, Christina Riesselman, Haroon Stephen, Andrew M. Lorrey

Geoscience Faculty Research

We show that climate and topography control the spatial distribution of stable isotope values on the South Island of New Zealand, based on a spatially dense (n = 193) river isotopic survey. Our data show a δ O minimum in isotope values east of the Southern Alps that demonstrates topographically driven continentality associated with the Southern Alps, which intersect the prevailing, moisture-laden westerlies. Our data define a South Island surface water line of δ H = 8.17 (±0.26) × δ O + 10.57 (±2.04), which is identical within 95% confidence intervals to the global and New Zealand meteoric water lines …

Organic Matter Spatial And Temporal Patterns In Coastal Sands Of Long Bay, South Carolina, Kayla B. Christofferson

Honors Theses

Sandy coastlines serve crucial functions to coastal economies and coastal ecology alike. In the past, organic-poor sands were considered of lower importance than organic-rich muds. Recent studies showed that sands’ low organic matter concentrations are due to high biogeochemical cycling rates, driven by rapid physical exchange, but remain infrequently studied. I present time-series of sand mass-loss-on-ignition (LOI, an organic matter proxy) profiles from February 2017 onwards at multiple sites along Long Bay, South Carolina. LOI profiles exhibit subsurface maximum values, unlike the typical decrease with depth in muddy sediments. I hypothesize that organic matter distribution with depth is affected by …

Isolated Point Discharges Into Coastal Swashes As Nutrient Sources To Coastal Waters, Mary E. Olsen

Honors Theses

Coastal water quality in the Grand Strand of South Carolina is directly influenced by human activities. Nutrient-rich runoff, stemming from numerous anthropogenic sources, finds its way into coastal waters through freshwater inputs often through tidal creeks, termed swashes. In order to better describe the amount of nutrient inputs into Singleton Swash and White Point Swash, we examine anthropogenic runoff from isolated identifiable point discharges and their nutrient concentrations. We report concentrations of dissolved inorganic nitrogen (DIN, as the sum of nitrate, nitrite and ammonium) and phosphate in discharge and creek water. We hypothesize that nutrient concentrations of isolated, minor point …

Small-Scale Resuspension And Redistribution Of Surface Sediments In The Northeast Gulf Of Mexico, Austin Harris

Master's Theses

Following the release of ~4.9 million barrels of oil into the Gulf of Mexico from the Macondo wellhead, a vast area of the seafloor contained recently deposited marine sediments contaminated by the oil spill. The initial deposition of these contaminated marine sediments was likely not the end of the journey for the particles. Downslope gravitational processes and events of increased current speed in the deep ocean setting can result in recently deposited sediments to resuspend and be moved laterally with the current flow, increasing the area effected by the oil spill. Erosion experiments performed in a closed-loop resuspension flume were …

Microplankton Dynamics In The River-Dominated Mississippi Bight, Adam D. Boyette

Dissertations

The Mississippi Bight (MSB) is a river-dominated continental margin influenced by multiple large river systems, including the Mississippi River, Alabama and Tombigbee rivers via Mobile Bay, and numerous smaller rivers, creeks, and bayous. This is part of a biologically-rich ecosystem that supports the second largest fishery industry by volume in the United States. Despite our understanding of the linkages between primary production with higher trophic levels, there remains limited studies quantifying these trophic interactions in this system. Microplankton (µm) community dynamics and trophic connectivity between primary producers and heterotrophic protists represent a critical nexus influencing overall biological productivity in this …