Geophysics and Seismology Commons^™

Sediment Transport And Geomorphological Evolution In The Transgressive Ship Shoal, Louisiana: Insights From Geophysical Observation, Modeling, And Machine Learning Studies, Haoran Liu

LSU Doctoral Dissertations

Ship Shoal has been a high-priority target sand resource for dredging activities to restore the eroding barrier islands in Louisiana, USA. Many studies have been performed in Ship Shoal in recent decades, but our knowledge of temporal and spatial variations of sediment transport and post-dredge morphology is still limited. The objectives of this dissertation are to explore the sediment infilling process, the spatial and temporal evolution of the morphology of dredge pits near and on Ship Shoal by using multiple methods. Scientific methods used in this study include (a) geophysical observation using bathymetry, side-scan and subbottom technique, (b) sediment transport …

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 …

Twentieth Century Black Carbon And Dust Deposition On South Cascade Glacier, Washington State, Usa, As Reconstructed From A 158‐M‐Long Ice Core, Susan D. Kaspari, Dan Pittenger, T. M. Jenk, U. Morgenstern, M. Schwikowski, N. Buenning, L. Stott

All Faculty Scholarship for the College of the Sciences

Light absorbing particles (LAPs) include black carbon (BC) and mineral dust and are of interest due to their positive radiative forcing and contribution to albedo reductions and snow and glacier melt. This study documents historic BC and dust deposition as well as their effect on albedo on South Cascade Glacier (SCG) in Washington State (USA) through the analysis of a 158‐m (139.5‐m water equivalent [w.e.]) ice core extracted in 1994 and spanning the period 1840–1991. Peak BC deposition occurred between 1940 and 1960, when median BC concentrations were 16 times higher than background, likely dominated by domestic coal and forest …

Atmospheric And Ionospheric Responses To Acoustic And Gravity Waves Driven By Earthquakes And Tsunamis, Pavel A. Inchin

Doctoral Dissertations and Master's Theses

Natural hazards (NHs) are causes for significant concern due to their potentially catastrophic impacts on society. The study of their effects on the upper atmosphere can provide significant insight into the coupled nature of geophysical processes, and drives important applications for radio communication and navigation, leading potentially to the development of NH early-warning systems. Although general concepts underlying their coupling mechanisms are well understood, recent computational capabilities, supported by high temporal and spatial density of observations, have reached the level where such processes can be modeled with unprecedented realism for detailed case studies. The studies provided in this thesis are …

Abiotic Formation Of Dissolved Organic Sulfur In Anoxic Sediments Of Santa Barbara Basin, Hussain A. Abdulla, David J. Burdige, Tomoko Komada

OES Faculty Publications

Sulfurization has been found to enhance organic matter preservation and petroleum formation in marine sediments. However, we do not yet have a comprehensive understanding of sulfurization mechanisms. In this study, we investigated several possible mechanisms of dissolved organic sulfur (DOS) formation in the top 4.5 m of anoxic sediments of Santa Barbara Basin (SBB), California Borderland. Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FTICR-MS), we identified chemical formulas of potential dissolved organic matter (DOM) precursors to these DOS compounds. We also examined how the formulas of abiotically formed DOS changed as a function of depth across a major redox …

Temporal And Spatial Scales Of Correlation In Marine Phytoplankton Communities, A. M. Kuhn, S. Dutkiewicz, O. Jahn, Sophie Clayton, T. A. Rynearson, M. R. Mazloff, A. D. Barton

OES Faculty Publications

Ocean circulation shapes marine phytoplankton communities by setting environmental conditions and dispersing organisms. In addition, processes acting on the water column (e.g., heat fluxes and mixing) affect the community structure by modulating environmental variables that determine in situ growth and loss rates. Understanding the scales over which phytoplankton communities vary in time and space is key to elucidate the relative contributions of local processes and ocean circulation on phytoplankton distributions. Using a global ocean ecosystem model, we quantify temporal and spatial correlation scales for phytoplankton phenotypes with diverse functional traits and cell sizes. Through this analysis, we address these questions: …

Land – Atmosphere – Meteorological Coupling Associated With The 2015 Gorkha (M 7.8) And Dolakha (M 7.3) Nepal Earthquakes, Feng Jing, Ramesh P. Singh, Xuhui Shen

Mathematics, Physics, and Computer Science Faculty Articles and Research

Multiple parameters (brightness temperature, soil moisture, surface latent heat flux, surface air temperature and carbon monoxide) before and after the 2015 Nepal M7.8 Gorkha main earthquake and M7.3 Dolakha aftershock were analysed using satellite observation data. The thermal anomalies from optical and microwave data appear about two months prior to the 2015 Gorkha earthquake. Some of the parameters show anomalous changes at different altitudes about 20 days prior to the main earthquake event and 10 days prior to the strong aftershock. Our results show that pre-earthquake anomalous signals propagate from the in situ to the top of atmosphere, and the …

Impacts Of Basin-Scale Climate Modes On Coastal Sea Level: A Review, Weiqing Han, Detlef Stammer, Philip Thompson, Tal Ezer, Hindu Palanisamy, Xuebin Zhang, Catia M. Domingues, Lei Zhang, Dongliang Yuan

CCPO Publications

Global sea level rise (SLR) associated with a warming climate exerts significant stress on coastal societies and low-lying island regions. The rates of coastal SLR observed in the past few decades, however, have large spatial and temporal differences from the global mean, which to a large part have been attributed to basin-scale climate modes. In this paper, we review our current state of knowledge about climate modes’ impacts on coastal sea level variability from interannual-to-multidecadal timescales. Relevant climate modes, their impacts and associated driving mechanisms through both remote and local processes are elaborated separately for the Pacific, Indian and Atlantic …

Hurricane Model Development At Gfdl: A Collaborative Success Story From A Historical Perspective, Morris A. Bender, Timothy Marchok, Robert E. Tuleya, Isaac Ginis, Vijay Tallapragada, Stephen J. Lord

CCPO Publications

The hurricane project at the National Oceanic and Atmospheric Administration (NOAA) Geophysical Fluid Dynamics Laboratory (GFDL) was established in 1970. By the mid-1970s pioneering research had led to the development of a new hurricane model. As the reputation of the model grew, GFDL was approached in 1986 by the director of the National Meteorological Center about establishing a collaboration between the two federal organizations to transition the model into an operational modeling system. After a multiyear effort by GFDL scientists to develop a system that could support rigorous requirements of operations, and multiyear testing had demonstrated its superior performance compared …

Late Quaternary Evolution And Stratigraphic Framework Influence On Coastal Systems Along The North-Central Gulf Of Mexico, Usa, Robert Hollis

Master's Theses

Coastal systems in the Gulf of Mexico are threatened to reduced sediment supply, storm impacts and relative sea level rise (RSLR). The geologic record can provide insights of geomorphic threshold crossings (formation, progradation, transgression, destruction) to these forcing mechanisms to predict future barrier evolution to climate change. The stratigraphic framework and antecedent topography directly influence coastal evolution over geologic timescales. This study synthesizes ~2100km of geophysical data, 700+ sediment cores, and 63 radiocarbon dates to regionally map two sequence boundaries, multiple ravinement surfaces and fourteen depositional facies. One marine isotope stage (MIS) 6 valley’s fill provided up to 300 x10 …

Predicted Deepwater Bathymetry From Satellite Altimetry: Non-Fourier Transform Alternatives, Maxsimo Salazar

Dissertations

Robert Parker (1972) demonstrated the effectiveness of Fourier Transforms (FT) to compute gravitational potential anomalies caused by uneven, non-uniform layers of material. This important calculation relates the gravitational potential anomaly to sea-floor topography. As outlined by Sandwell and Smith (1997), a six-step procedure, utilizing the FT, then demonstrated how satellite altimetry measurements of marine geoid height are inverted into seafloor topography. However, FTs are not local in space and produce Gibb’s phenomenon around discontinuities. Seafloor features exhibit spatial locality and features such as seamounts and ridges often have sharp inclines. Initial tests compared the windowed-FT to wavelets in reconstruction of …

Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World, Kira H. Hamman

Numeracy

Timothy H. Dixon. 2017. Curbing Catastrophe: Natural Hazards and Risk Reduction in the Modern World. (New York, NY: Cambridge University Press) 300 pp. ISBN 978-1108113663.

In Curbing Catastrophe, Timothy H. Dixon explores commonalities among natural disasters like Hurricane Katrina, the 2010 earthquake in Haiti, and the meltdown at Fukushima. He identifies communication failure between scientists and policy makers as a major culprit in the devastation that results from such events and offers strategies for improving that communication. He includes optional in-depth scientific and quantitative examinations of the events and the resulting devastation, making the book appropriate for use …

Theory And Application Of Geophysical Geodesy For Studying Earth Surface Deformation, Makan A. Karegar

USF Tampa Graduate Theses and Dissertations

An interdisciplinary approach at the interface between geodesy and geophysics has recently resolved several Earth science problems at regional and global scales. I use the term “geophysical geodesy” to distinguish the technical and theoretical aspect of geodesy from geophysical applications of geodetic techniques. Using a wide range of Earth observation data, I study the spatio-temporal characteristics of Earth surface deformation in the United States associated with several geophysical processes, including natural and anthropogenic subsidence and uplift, regional relative sea-level rise, and continental hydrological loading. The theoretical portion of this dissertation applies loading theory and develops a new hybrid method to …

Caves As Observatories For Atmospheric Thermal Tides: An Example From Ascunsă Cave, Romania, Virgil Drăgușin, Laura Tîrlă, Nicoleta Cadicheanu, Vasile Ersek, Ionuț Mirea

International Journal of Speleology

As part of a microclimate study at Ascunsă Cave, Romania, we used Gemini Tinytag Plus 2 data loggers to record cave air temperature variability. At one of the monitoring points we recognized the presence of semidiurnal cycles on the order of a few thousands of a degree Celsius that could be produced under the influence of the semidiurnal tidal components of the Sun (S₂) or the Moon (M₂). Using a Gemini Tinytag Plus 2 data logger with an external probe we measured core rock temperature and showed that it does not influence the cave air temperature …

Climate Change On The Quelccaya Ice Cap, Central Andes, And Its Relationship With The Large-Scale Circulation, Christian Pedro Yarleque Galvez

Legacy Theses & Dissertations (2009 - 2024)

Glaciated areas over the central Andes are highly sensitive to atmospheric forcings, as demonstrated by their current accelerated retreat in response to global warming. The present Thesis is focused on quantifying and assessing future climate change impacts over Quelccaya ice cap (QIC), the world-largest tropical ice body, which is considered as a representative case of the tropical Andean cryosphere. I focused my study on characterizing large-scale forcing and future changes of precipitation and temperature, since they represent the most important variables for accumulation and ablation processes in glaciated mountain regions. In my research I developed tools to overcome the lack …

Combined Assimilation Of Satellite Precipitation And Soil Moisture: A Case Study Using Trmm And Smos Data, Liao-Fan Lin, Ardeshir M. Ebtehaj, Alejandro N. Flores, Satish Bastola, Rafael L. Bras

Geosciences Faculty Publications and Presentations

This paper presents a framework that enables simultaneous assimilation of satellite precipitation and soil moisture observations into the coupled Weather Research and Forecasting (WRF) and Noah land surface model through variational approaches. The authors tested the framework by assimilating precipitation data from the Tropical Rainfall Measuring Mission (TRMM) and soil moisture data from the Soil Moisture Ocean Salinity (SMOS) satellite. The results show that assimilation of both TRMM and SMOS data can effectively improve the forecast skills of precipitation, top 10-cm soil moisture, and 2-m temperature and specific humidity. Within a 2-day time window, impacts of precipitation data assimilation on …

3d Seismic Interpretation Of A Plio-Pleistocene Mass Transport Deposit In The Deepwater Taranaki Basin Of New Zealand, Francisco Jose Rusconi

Graduate Theses and Dissertations

A series of Plio-Pleistocene mass transport deposits (MTD) have been identified in the deepwater Taranaki Basin, in New Zealand, using the Romney 3D seismic survey, which covers an area of approximately 2000 km2. One of these MTDs has been chosen for description and interpretation based on high confidence mapping of its boundary surfaces. The deposit exhibits an array of interesting features similar to those documented by researchers elsewhere plus a unique basal feature unlike those previously observed. The basal shear surface exhibits erosional features such as grooves, “monkey fingers”, and glide tracks. Internally, the MTD is typically characterized by low …

How Dredge Pits Evolve Over Time: A Look At Their Geomorphologic Evolution And Infilling Processes, Patrick Robichaux

LSU Master's Theses

As coastal environments become more susceptible to land loss through accelerating sea level rise and subsidence, new restoration methods harnessing borrowed sediment are more valuable than ever. Mud-capped dredge pits (MCDPs) are a relatively new source of restoration-quality sediment that has only recently been utilized for beach and barrier island restorations in Louisiana. Because MCDPs have been in use for less than two decades in only a handful sites, little is understood about their evolution over decadal timescales. To improve our understanding of MCDPs after they are dredged, we have conducted a suite of geophysical surveys including bathymetry, sidescan sonar, …

Thermal Radiation Anomalies Associated With Major Earthquakes, Dimitar Ouzounov, Sergey Pulinets, Menas Kafatos, Patrick Taylor

Mathematics, Physics, and Computer Science Faculty Articles and Research

Recent developments of remote sensing methods for Earth satellite data analysis contribute to our understanding of earthquake related thermal anomalies. It was realized that the thermal heat fluxes over areas of earthquake preparation is a result of air ionization by radon (and other gases) and consequent water vapor condensation on newly formed ions. Latent heat (LH) is released as a result of this process and leads to the formation of local thermal radiation anomalies (TRA) known as OLR (outgoing Longwave radiation, Ouzounov et al, 2007). We compare the LH energy, obtained by integrating surface latent heat flux (SLHF) over the …

Evidence For Late Pliocene Deglacial Megafloods From Giant Sediment Waves In The Northern Gulf Of Mexico, Zexuan Wang

Masters Theses & Specialist Projects

Laurentide Ice Sheet outburst floods to the Gulf of Mexico have been mainly documented based on deep-sea cores, especially the megafloods, only during the last several interglacial episodes in the late Pleistocene. The paleoclimatic significance of giant sedimentary structures developed under unconfined Froude-supercritical turbidity currents in subaqueous settings is considerably under-examined. This research extensively documents >20-km-wide and 200-m-thick Plio-Pleistocene giant sediment waves for the first time on the northern Gulf of Mexico continental slope using 3D seismic data, which show waveform morphology in unprecedented detail. The results suggest that such large-scale bedforms were formed under sheet-like unconfined Froudesupercritical turbidity currents …

Satellite Observation Of Ch4 And Co Anomalies Associated With The Wenchuan Ms 8.0 And Lushan Ms 7.0 Earthquakes In China, Y. Cui, Dimitar Ouzounov, N. Hatzopoulos, K. Sun, Z. Zou, J. Du

Mathematics, Physics, and Computer Science Faculty Articles and Research

Spatial and temporal variations of total column of CH4 and CO (TotCH4 and TotCO) associated with the 12 May 2008 Wenchuan and 20 April 2013 Lushan earthquakes in western Sichuan, China were investigated using satellite data from AQUA AIRS in order to understand the lithospheric and atmospheric interactions during the seismic activity. The Wenchuan MS 8.0 and Lushan MS7.0 earthquakes occurred in the Longmenshan fault zone. It was observed that large amounts of gases emitted from the earth's crust into the atmosphere before, during and after the earthquakes. The anomalies of TotCH4 and TotCO occurred along the …

Assessing Seasonal And Spatial Variability In The Hydrogeochemistry Of Glacial Meltwater In Iceland, Anisha Tuladhar

Masters Theses & Specialist Projects

A detailed comparative geochemical characterization of three different types of Iceland glacial systems was conducted during June, August, and October, 2016. The study was carried out at a total of 11 outlet glacier rivers flowing from the icecaps Vatnajökull, Eyjafjallajökull, and Mýrdalsjökull. A total of 75 grab samples were collected (25 for each sampling period). The hydrogeochemical variations of Icelandic glacial meltwater are influenced by volcanic activity, temporal changes, and geographical location, which differed between the sampling sites within the glaciers and icecaps. Lower pH range, and comparatively higher and variable specific conductivity, SO4, S and F is linked to …

Synoptic Atmospheric Conditions, Land Cover, And Equivalent Temperature Variations In Kentucky, Dorothy Yemaa Na-Yemeh

Masters Theses & Specialist Projects

Research has demonstrated that equivalent temperature (T_E), which incorporates both the surface air temperature (T) and moist heat content associated with atmospheric moisture, is a better indicator of overall heat content. This thesis follows up on a study that used T_E to determine the impacts of land use/land cover and air masses on the atmospheric heat content over Kentucky during the growing season (April-September). The study, which used data from the Kentucky Mesonet, reveals that moist weather types dominate the growing season and, as expected, differences between T and T_E are smaller under dry atmospheric conditions …

Contributions Of Wood Smoke And Vehicle Emissions To Ambient Concentrations Of Volatile Organic Compounds And Particulate Matter During The Yakima Wintertime Nitrate Study, Graham Vanderschelden, Benjamin De Foy, Courtney Herring, Susan D. Kaspari, Tim Vanreken, Bertram Jobson

All Faculty Scholarship for the College of the Sciences

A multiple linear regression (MLR) chemical mass balance model was applied to data collected during an air quality field experiment in Yakima, WA, during January 2013 to determine the relative contribution of residential wood combustion (RWC) and vehicle emissions to ambient pollutant levels. Acetonitrile was used as a chemical tracer for wood burning and nitrogen oxides (NOx) as a chemical tracer for mobile sources. RWC was found to be a substantial source of gas phase air toxics in wintertime. The MLR model found RWC primarily responsible for emissions of formaldehyde (73%), acetaldehyde (69%), and black carbon (55%) and mobile sources …

Implications Of Sea Ice On Southern Ocean Microseisms Detected By A Seismic Array In West Antarctica, Martin J. Pratt, Douglas A. Wiens, J. Paul Winberry, Sridhar Anandakrishnan, Garrett G. Euler

All Faculty Scholarship for the College of the Sciences

The proximity of Southern Ocean storms coupled with seasonal variation in sea ice make Antarctica ideal for the study of microseism sources. We explore frequency-dependent beamforming results using a short-duration, 60 km aperture, broad-band seismic array located on the Whillans Ice Stream, West Antarctica. Locations of single-frequency microseism (13–16 s period) generation are in regions where the continental shelf is ice-free, consistent with previous studies, and show Rayleigh wave sources remaining at consistent backazimuths throughout the duration of the array. Beamforming analysis of daily noise correlations shows that long-period double-frequency microseisms (9–11 s) consist predominantly of Rayleigh waves excited by …

Mapping The Nonstationary Internal Tide With Satellite Altimetry, Edward Zaron

Civil and Environmental Engineering Faculty Publications and Presentations

t Temporal variability of the internal tide has been inferred from the 23 year long combined records of the TOPEX/Poseidon, Jason-1, and Jason-2 satellite altimeters by combining harmonic analysis with an analysis of along-track wavenumber spectra of sea-surface height (SSH). Conventional harmonic analysis is first applied to estimate and remove the stationary components of the tide at each point along the reference ground tracks. The wavenumber spectrum of the residual SSH is then computed, and the variance in a neighborhood around the wavenumber of the mode-1 baroclinic M2 tide is interpreted as the sum of noise, broadband nontidal processes, and …

Spatial Patterns Of Sea Level Variability Associated With Natural Internal Climate Modes, Weiqing Han, Gerald A. Meehl, Detlef Stammer, Aixue Hu, Benjamin Hamlington, Jessica Kenigson, Hindumathi Palanisamy, Philip Thompson

OES Faculty Publications

Sea level rise (SLR) can exert significant stress on highly populated coastal societies and low-lying island countries around the world. Because of this, there is huge societal demand for improved decadal predictions and future projections of SLR, particularly on a local scale along coastlines. Regionally, sea level variations can deviate considerably from the global mean due to various geophysical processes. These include changes of ocean circulations, which partially can be attributed to natural, internal modes of variability in the complex Earth's climate system. Anthropogenic influence may also contribute to regional sea level variations. Separating the effects of natural climate modes …

Subsidence Monitoring In Hampton Roads Using Satellites, Ben Hamlington

July 29, 2016: The Latest in Sea Level Rise Science

No abstract provided.

Applications Of Satellite Geodesy In Environmental And Climate Change, Qian Yang

USF Tampa Graduate Theses and Dissertations

Satellite geodesy plays an important role in earth observation. This dissertation presents three applications of satellite geodesy in environmental and climate change. Three satellite geodesy techniques are used: high-precision Global Positioning System (GPS), the Gravity Recovery and Climate Experiment (GRACE) and Interferometric Synthetic Aperture Radar (InSAR). In the first study, I use coastal uplift observed by GPS to study the annual changes in mass loss of the Greenland ice sheet. The data show both spatial and temporal variations of coastal ice mass loss and suggest that a combination of warm atmospheric and oceanic condition drove these variations. In the second …

Crop Modeling For Assessing And Mitigating The Impacts Of Extreme Climatic Events On The Us Agriculture System, Zhenong Jin

Open Access Dissertations

The US agriculture system is the world’s largest producer of maize and soybean, and typically supplies more than one-third of their global trading. Nearly 90% of the US maize and soybean production is rainfed, thus is susceptible to climate change stressors such as heat waves and droughts. Process-based crop and cropping system models are important tools for climate change impact assessments and risk management. As data- science is becoming a new frontier for agriculture growth, the incoming decade calls for operational platforms that use hyper-local growth monitoring, high-resolution real-time weather and satellite data assimilation and cropping system modeling to help …