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Monitoring Air Fluxes In Caves Using Digital Flow Metres, Claudio Pastore, Amir Sedaghatkish, Eric Weber, Nicolas Schmid, Pierre-Yves Jeannin, Marc Luetscher Jun 2024

Monitoring Air Fluxes In Caves Using Digital Flow Metres, Claudio Pastore, Amir Sedaghatkish, Eric Weber, Nicolas Schmid, Pierre-Yves Jeannin, Marc Luetscher

International Journal of Speleology

Precise measurements of airflow within caves are increasingly demanded to assess heat and mass transfers and their impacts on the karst environment, including subsurface ecosystems, hydrochemistry of karst water and secondary mineral precipitates. In this study, we introduce a new, low-cost and lightweight device adapted to monitoring air fluxes in caves which addresses the need for reliable measurements, low power consumption, durability and affordability. The device was calibrated in a wind tunnel, showing the high accuracy and precision of the device. Field-related uncertainties were further investigated in a ventilated cave to determine the effect of local airflow conditions on the …


Iron Isotope Transformations In Saanich Inlet, Claire Onak Apr 2024

Iron Isotope Transformations In Saanich Inlet, Claire Onak

USF Tampa Graduate Theses and Dissertations

Iron (Fe) is required for many biogeochemical processes, with Fe bioavailability and chemistry being controlled by redox reactions that transform Fe between oxidation states and dissolved and particulate phases. In oxic seawater, Fe is present in the Fe(III) oxidation state, mainly as Fe oxyhydroxides. Under anoxic marine conditions, such as margin sediments under oxygen minimum zones or restricted basins with anoxic bottom water, Fe(III) is reduced to Fe(II), which is highly soluble and can be present at high concentrations ([Fe]). Fe isotope ratios (δ56Fe relative to IRMM-14) can be used to characterize Fe redox transformations, constrain Fe sources of Fe …


Thermal Ecology And Swimming Performance Of Native Tadpoles Dryophytes Femoralis In Central Florida, Jessalyn Aretz Mar 2024

Thermal Ecology And Swimming Performance Of Native Tadpoles Dryophytes Femoralis In Central Florida, Jessalyn Aretz

USF Tampa Graduate Theses and Dissertations

Urbanization and climate warming have contributed to global amphibian declines in recent decades. Amphibians are particularly vulnerable to climate and urban-induced warming because their physiological processes are dependent on temperature across all life stages, but few studies have been done on tadpole responses to warming in comparison to adult responses. The study objective was to determine how the thermal ecology and swimming performance of a native Florida tadpole varied with rearing temperature and urban level, and whether these traits are plastic or adaptive. We collected eggs from wild populations of pine woods treefrog (Dryophytes femoralis) tadpoles at an urban and …


Labile Dissolved Nickel (Ni) Concentrations In The North Pacific, Calyn M. Crawford Oct 2023

Labile Dissolved Nickel (Ni) Concentrations In The North Pacific, Calyn M. Crawford

USF Tampa Graduate Theses and Dissertations

Nickel (Ni) is an important micronutrient for phytoplankton and bacteria that serves as a required co-factor in several metalloenzymes. Despite these known biological uses, total dissolved Ni concentrations remain elevated in global surface waters, in contrast to the surface depletion commonly observed for macronutrients and other nutrient-type trace elements. A prevailing hypothesis for the muted depletion of dissolved Ni concentrations in surface waters is that dissolved Ni in seawater is not in a bioavailable form. The chemical lability of Ni in seawater provides insight into Ni speciation and bioavailability, but few measurements have been made in the open ocean to …


Stable Isotope Analysis On Yellowfin And Blackfin Tuna Eye Lenses Reveals Life History Patterns In The Gulf Of Mexico, Kylee M. Rullo Oct 2023

Stable Isotope Analysis On Yellowfin And Blackfin Tuna Eye Lenses Reveals Life History Patterns In The Gulf Of Mexico, Kylee M. Rullo

USF Tampa Graduate Theses and Dissertations

Spatial geography, ontogenetic movement, and trophic patterns of mobile species are key elements of effective marine resource management. A number of methods are currently available for tracking movements of pelagic migratory species, including the use of conventional and electronic tags. However, tagging campaigns can take years to provide useful data, can be expensive, and only capture a portion of a fish’s lifetime. For this project, I used stable-isotopic ratios of nitrogen (δ15N) and carbon (δ13C) in metabolically inert, chronologically-layered fish-eye lenses to explore lifetime movement and trophic patterns of yellowfin tuna (Thunnus albacares) and blackfin tuna (Thunnus atlanticus) in the …


Meta-Analysis Of United States Seabird Populations Based On Ocean Biodiversity Information System (Obis) Records (1965–2018), Savannah Hartman Jul 2023

Meta-Analysis Of United States Seabird Populations Based On Ocean Biodiversity Information System (Obis) Records (1965–2018), Savannah Hartman

USF Tampa Graduate Theses and Dissertations

Understanding the distribution of organisms is an important priority for society as we live through ecosystem transformations that threaten the well-being of all organisms. I have approached the dynamic and complex issue of studying biodiversity by using open-access seabird data collected along the Americas since the 1960s. I explained how these data have changed over time and space, how certain species populations could have shifted over time, and possible correlations between this potential geographic change and select environmental variables.

In Chapter 2 I evaluated the suitability of the open-access data archive Ocean Biodiversity Information System (OBIS) for supporting detailed inquiry …


Exploring The Impact Of Eddies On Southern Ocean Biogeochemical Structure Using Bgc-Argo Float Observations, Nicola J. Guisewhite Jul 2023

Exploring The Impact Of Eddies On Southern Ocean Biogeochemical Structure Using Bgc-Argo Float Observations, Nicola J. Guisewhite

USF Tampa Graduate Theses and Dissertations

The Southern Ocean plays a crucial role in global ocean circulation, and global heat and nutrient transport. However, this region is both distant and dangerous and is therefore largely under-sampled and understudied. Methods to fill in biogeochemical data-gaps include using limited in-situ data in models to output biogeochemical property estimates, but a number of recent studies have raised concerns about how most Southern Ocean models do not resolve eddies. Eddies are known to impact biogeochemistry around the globe but little is known about their impact in the Southern Ocean. This study examines temperature, salinity, oxygen, nitrate, and dissolved inorganic carbon …


Climate Of A Cave Laboratory Representative For Rock Art Caves In The Vézère Area (South-West France), Delphine Lacanette, Léna Bassel, Fabien Salmon, Jean-Christophe Portais, Bruno Bousquet, Rémy Chapoulie, Faten Ammari, Philippe Malaurent, Catherine Ferrier Jun 2023

Climate Of A Cave Laboratory Representative For Rock Art Caves In The Vézère Area (South-West France), Delphine Lacanette, Léna Bassel, Fabien Salmon, Jean-Christophe Portais, Bruno Bousquet, Rémy Chapoulie, Faten Ammari, Philippe Malaurent, Catherine Ferrier

International Journal of Speleology

Leye Cave (Dordogne, France) is a laboratory cave in the Vézère area, a region that contains some of the most famous rock art caves in the world such as Lascaux, Font-de-Gaume and Combarelles, and is listed as Human World Heritage by UNESCO. Leye Cave was selected because it is representative of painted caves, with respect to parameters such as its geological stage, the presence of water and carbon dioxide, the geological state of its walls, and the size of the cave. These wall states are studied to better understand the conditions of conservation of rock art caves without damaging them. …


Environmental Chemical Analysis Method Optimization And Application To Northwest Cuban Marine Sediment, Thea R. Bartlett Jun 2023

Environmental Chemical Analysis Method Optimization And Application To Northwest Cuban Marine Sediment, Thea R. Bartlett

USF Tampa Graduate Theses and Dissertations

A method for gas chromatography tandem mass spectrometry (GC-MS/MS) in selected reaction monitoring (SRM) mode has been optimized to quantify 250 compounds of a variety of compound classes such as polycyclic aromatic hydrocarbons (PAHs), oxidized PAHs, organochlorinated pesticides, polychlorinated biphenyls, biomarkers (hopanes, steranes, tri-aromatic steroids, and fecal sterols), aliphatic hydrocarbons, and plastic additives. This method was validated based on available QA/QC standards using several environmental samples, both sediment and biota, and standard reference materials. This contaminant-focused method can be used as a forensic geochemistry tool to evaluate oil contamination and other contaminant histories in future research studies. When applied to …


Stable Isotope Analysis Of Doryteuthis (Amerigo) Pealeii Eye Lenses To Determine Migratory Patterns In The Eastern Gulf Of Mexico Using Statoliths For Age Determination, Hannah M. Schwaiger Jun 2023

Stable Isotope Analysis Of Doryteuthis (Amerigo) Pealeii Eye Lenses To Determine Migratory Patterns In The Eastern Gulf Of Mexico Using Statoliths For Age Determination, Hannah M. Schwaiger

USF Tampa Graduate Theses and Dissertations

Doryteuthis (Amerigo) pealeii is a common fisheries squid that occurs in the Gulf of Mexico (GoM) and along the east coast of the United States. These squid are an important link in the food web, linking higher and lower trophic positions (Madsen et al., 2007), and they are also used for human consumption. The migration patterns of D. pealeii populations in the northwestern North Atlantic have been thoroughly studied when compared to those in the GoM. This research aims to combine statolith aging and stable isotope analysis to enhance the understanding of D. pealeii migration patterns throughout their short, sub-annual …


Airflow Dynamics In Wind Cave And Jewel Cave: How Do Barometric Caves Breathe?, Annika K. Gomell, Andreas Pflitsch Oct 2022

Airflow Dynamics In Wind Cave And Jewel Cave: How Do Barometric Caves Breathe?, Annika K. Gomell, Andreas Pflitsch

International Journal of Speleology

Recent research on air pressure propagation through barometric caves has revealed various speleoclimatological processes, which cause a more complex relationship between surface air pressure changes and resulting pressure gradients between cave and surface air than previously assumed. So far, however, studies on barometric cave airflow have only been based on surface air pressure measurements. Thus, this study investigates and compares airflow at the openings of Wind Cave and Jewel Cave – two major barometric cave systems in South Dakota, USA – as a response to surface air pressure changes and air pressure gradients. Based on high-resolution long-term air pressure measurements …


Inland Tropical Cyclone Intensity Decay In The Continental United States, Yijie Zhu Jul 2022

Inland Tropical Cyclone Intensity Decay In The Continental United States, Yijie Zhu

USF Tampa Graduate Theses and Dissertations

Tropical cyclone (TC) hazard preparation is mostly focused on coastal cities with less attention typically paid to inland regions. The impact of TCs that propagate far inland is often underestimated and can cause unexpected loss of life and economic loss. This dissertation aims to understand the decay process of TCs during the post-landfall stage by answering three main research questions: (1) What are the general patterns of inland tropical cyclones, including spatial variations, decay rates, and translation speeds? (2) Are there temporal changes in the intensity decay from inland moving hurricanes? (3) How is the hurricane post-landfall dissipation related to …


The Effects Of Temperature And Oxygen Availability On Aerobic Performance In Three Coastal Shark Species; Squalus Acanthias, Carcharhinus Limbatus, And Carcharhinus Leucas, Alyssa M. Andres Jul 2022

The Effects Of Temperature And Oxygen Availability On Aerobic Performance In Three Coastal Shark Species; Squalus Acanthias, Carcharhinus Limbatus, And Carcharhinus Leucas, Alyssa M. Andres

USF Tampa Graduate Theses and Dissertations

Anthropogenically driven climate changes are altering marine habitats globally. Rising sea surface temperatures and coastal eutrophication, arising from global warming and coastal nutrient loading, have resulted in progressive ocean deoxygenation. This may restrict available habitat of marine organisms as studies suggest that the balance between metabolic oxygen demand and environmental supply plays an important role in limiting viable habitat and species fitness. As ectothermic predators, with temperature-dependent metabolism and high metabolic demands, coastal shark species may be susceptible to shifts in ocean temperature and oxygen. Such environmental changes may alter metabolic performance and ultimately success and survival within shark habitat. …


Zooplankton Biodiversity In The Northeast Gulf Of Mexico And On The West Florida Shelf From 2005 - 2014, Megan Ferguson Jul 2022

Zooplankton Biodiversity In The Northeast Gulf Of Mexico And On The West Florida Shelf From 2005 - 2014, Megan Ferguson

USF Tampa Graduate Theses and Dissertations

Zooplankton abundance and biodiversity was measured in the northeast Gulf of Mexico (NEGoM) and on the West Florida Shelf. Bongo net samples were collected between May 2005 to September 2009 through the SEAMAP program, and between July 2010 to August 2014 through the C-IMAGE program. Calanoid copepods were the most abundant zooplankton group in most of the samples collected, but ostracods, larvaceans, and chaetognaths were also abundant. Shannon and Inverse Simpson indices were calculated for all zooplankton samples and generally showed similar trends, but only Shannon indices were used for statistical analyses. In the winter and spring there were significant …


Elucidating The Sources Supplying Aerosol Iron, Zinc, And Cadmium To The Surface Of The North Pacific Ocean With Stable Isotopes, Zach B. Bunnell Jul 2022

Elucidating The Sources Supplying Aerosol Iron, Zinc, And Cadmium To The Surface Of The North Pacific Ocean With Stable Isotopes, Zach B. Bunnell

USF Tampa Graduate Theses and Dissertations

Transition metals, such as iron (Fe), zinc (Zn) and cadmium (Cd), are found at just trace amounts within the global oceans yet are vital for many biological functions of phytoplankton. As a result, these metals influence the ocean’s efficacy for carbon sequestration. Atmospheric dust is the primary input of Fe to various surface waters and may also supply Zn and Cd to oligotrophic surface waters. Here, I present Fe, Zn, and Cd isotope data from the US North Pacific GEOTRACES Section GP15 (Alaska-Tahiti) from the low-dust season (Sept. – Nov. 2018). Using this data and aerosol enrichment factors, I show …


Modeling Air Pressure Propagation Through Wind Cave And Jewel Cave: How Can Air Pressure Signals Inside Barometric Caves Be Predicted From Surface Pressure Measurements?, Annika K. Gomell, Andreas Pflitsch Apr 2022

Modeling Air Pressure Propagation Through Wind Cave And Jewel Cave: How Can Air Pressure Signals Inside Barometric Caves Be Predicted From Surface Pressure Measurements?, Annika K. Gomell, Andreas Pflitsch

International Journal of Speleology

Recent speleoclimatological research has shed new light on air pressure dynamics inside barometric caves by identifying pressure-modifying processes and resulting systematic differences between cave and surface air pressure. Based on these new findings, a multi- step quantitative model is developed and explored to predict air pressure inside Wind Cave and Jewel Cave – two major barometric cave systems in the Black Hills of South Dakota, USA – from external surface measurements. Therefore, each identified speleoclimatological pressure process is translated into a mathematical operation. Model evaluation based on Pearson correlation and mean (absolute) deviation between model outputs and control measurements yields …


Empirical And Modeled Δ13c And Δ15n Isoscapes In The Gulf Of Mexico And Their Application To Fish Eye Lens Migration Studies, Brianna Michaud Apr 2022

Empirical And Modeled Δ13c And Δ15n Isoscapes In The Gulf Of Mexico And Their Application To Fish Eye Lens Migration Studies, Brianna Michaud

USF Tampa Graduate Theses and Dissertations

Isoscapes are depictions of the spatial patterns of isotopic values in a given area. Isoscapes can be created using measurements form samples (empirical isoscapes) or using statistical models of spatial isotopic variation (modeled isoscapes). Isoscapes have a wide variety of potential applications though, in the realm of marine ecology, they are most often used infer ecological processes, food web linkages, the origin of samples, and the movements of marine organisms.

However, to use isoscapes for these applications, it is necessary to have isoscapes at spatial scales relevant to the application in question. It is also necessary to have isoscapes that …


Assessing Changes In Actual Air Quality And Public Perceptions Of Air Quality In Kathmandu Valley Nepal Pre And Post Covid-19 Lockdown, Robin Margherita Rives Mar 2022

Assessing Changes In Actual Air Quality And Public Perceptions Of Air Quality In Kathmandu Valley Nepal Pre And Post Covid-19 Lockdown, Robin Margherita Rives

USF Tampa Graduate Theses and Dissertations

Air pollution is a global concern. Cities around the world fail to meet air quality standards set by the World Health Organization Air Quality Guidelines, which has a significant impact on public health. As the capital city and largest metropolitan region of Nepal, Kathmandu is a hotspot for urban pollution in South Asia. Nepal faces emissions from both internal and external sources. External sources include emissions from Nepal’s neighboring countries of India and China and emissions resulting from tourism. Internal sources of pollution in the country include brick and cement factories, consumption of energy from traditional sources such as biomass, …


Quantitative Assessment Of The Trophic Ecology Of The Oceanic Ctenophore, Bolinopsis Infundibulum, In Monterey Bay, California, Victoria C. Scriven Mar 2022

Quantitative Assessment Of The Trophic Ecology Of The Oceanic Ctenophore, Bolinopsis Infundibulum, In Monterey Bay, California, Victoria C. Scriven

USF Tampa Graduate Theses and Dissertations

Bolinopsis infundibulum is a wide-ranging, ubiquitous ctenophore whose fragile nature makes the collection of specimens and quantification of key predator-prey activities in controlled laboratory experiments, challenging. Thus, in situ methods often represent the best means for data collection. However, while present in surface waters, these animals can also be abundant at depths well beyond those attainable by divers. As a result, very little empirical data exist over the depth range of their natural habitats which limits our ability to assess key predator-prey interactions needed to assess their ecological role in midwater food webs. Working in Monterey Bay, California, remotely operated …


Anthropogenic Impacts On The Glowworm Cave, Waitomo, New Zealand: A Microclimate Management Approach, Chris Hendy, David J. Merritt, Shannon Corkill Feb 2022

Anthropogenic Impacts On The Glowworm Cave, Waitomo, New Zealand: A Microclimate Management Approach, Chris Hendy, David J. Merritt, Shannon Corkill

International Journal of Speleology

Waitomo Glowworm Cave is a highly visited cave where the highlight is viewing the bioluminescence display of a large colony of glowworms. The visitation levels result in the build-up of anthropogenic CO2, to the extent that it could cause corrosion of speleothems. The cave experiences chimney-effect ventilation with air flowing either upward or downward through the main cave chambers depending on air density differences between the cave and the outside environment. Lack of airflow leads to CO2 build-up; however, unrestricted airflow can draw in cool, dry air which is harmful to the glowworms. Consequently, airflow is managed …


Low Impact Sampling Of Speleothems – Reconciling Scientific Study With Cave Conservation, Claire L.V. Macgregor, John C. Hellstrom, Jon D. Woodhead, Russell N. Drysdale, Rolan S. Eberhard Nov 2021

Low Impact Sampling Of Speleothems – Reconciling Scientific Study With Cave Conservation, Claire L.V. Macgregor, John C. Hellstrom, Jon D. Woodhead, Russell N. Drysdale, Rolan S. Eberhard

International Journal of Speleology

Speleothems are increasingly valued as important paleoclimate archives and yet the removal of samples from caves can come at a cost to natural heritage, impacting delicate environments with limited mechanisms for repair. Conservation of cave environments is a key responsibility for scientists and, with this in mind, we are working to develop and implement techniques that allow us to extract valuable scientific data, with minimal impact. In this study, we demonstrate the utility of low-impact reconnaissance dating surveys on caves in southern Tasmania and southwest Western Australia as a precursor to the removal of stalagmites for paleoclimate reconstruction. Small flakes …


Riverine And Estuarine Co2-System Studies On The West Coast Of Florida, Christopher S. Moore Nov 2021

Riverine And Estuarine Co2-System Studies On The West Coast Of Florida, Christopher S. Moore

USF Tampa Graduate Theses and Dissertations

Coastal and estuarine acidification impacts ecosystem health and economic resources and has both natural and anthropogenic components (Cai et al., 2021). Riverine input is one of several important factors that can influence acidification in coastal ecosystems. Rivers disgorging into coastal environments can create strong gradients, both spatial and temporal, that make accurate CO2-system characterization challenging. The work described in this thesis provides a baseline CO2-system study of four major rivers that flow into Tampa bay with an emphasis on seasonal change. As a second objective, this thesis examines the effects of HgII additions on CO2-system measurements in organic-rich estuarine waters. …


Continuous Color Model As A Tool To Improve Speleothem Age Model Development, Celia Campa-Bousoño, Ángel García-Pérez, Ana Moreno, Miguel Iglesias, Hai Cheng, R Lawrence Edwards, Heather Stoll Oct 2021

Continuous Color Model As A Tool To Improve Speleothem Age Model Development, Celia Campa-Bousoño, Ángel García-Pérez, Ana Moreno, Miguel Iglesias, Hai Cheng, R Lawrence Edwards, Heather Stoll

International Journal of Speleology

Because they can archive a variety of geochemical proxies and be precisely and accurately dated with the U-Th decay series chronometer, stalagmites are widely used for paleoclimate reconstructions. However, limitations in the use of this chronometer arise because U-Th dating is analytically time consuming, expensive, and requires a relatively large sample size. These limitations restrict the number of absolute dates usually obtained, which can result in significant uncertainties in the age model and inhibit the ability to archive high resolution records of environmental variability, particularly in those stalagmites where there are variations in growth rate not constrained by U-Th dates. …


Air Pressure Propagation Through Wind Cave And Jewel Cave: How Do Pressure Waves Travel Through Barometric Caves?, Annika K. Gomell, Daniel C. Austin, Marc J. Ohms, Andreas Pflitsch Sep 2021

Air Pressure Propagation Through Wind Cave And Jewel Cave: How Do Pressure Waves Travel Through Barometric Caves?, Annika K. Gomell, Daniel C. Austin, Marc J. Ohms, Andreas Pflitsch

International Journal of Speleology

In barometric caves, air pressure gradients between the outside atmosphere and the cave induce strong bidirectional compensating currents, which control almost all elements of speleoclimatology, including air temperature, humidity, and CO2 dynamics. Therefore, this study set out to investigate air pressure propagation through Wind Cave and Jewel Cave – two major barometric cave systems in the Black Hills of South Dakota, USA. Based on high-resolution air pressure data from both the surface and several measurement sites inside the caves, four systematic changes of pressure waves during their journey through the caves and their related speleoclimatological processes were identified and …


From River To Sea: Improving Carbon System Measurement Methods For Use In Rivers, Estuaries, And Oceans, Ellie Hudson-Heck Aug 2021

From River To Sea: Improving Carbon System Measurement Methods For Use In Rivers, Estuaries, And Oceans, Ellie Hudson-Heck

USF Tampa Graduate Theses and Dissertations

Over the last 30 years, spectrophotometric methodologies have been developed, with increasing rigor, to accurately measure all four carbon system parameters: total alkalinity (AT), total carbon (CT), partial pressure of CO2 (pCO2), and pH. Spectrophotometric measurements of carbon system parameters rely on quantitative characterizations of the response of sulfonephthalein indicator dyes (e.g., meta-cresol purple (mCP), thymol blue (TB), and bromocresol purple (BCP)) to changing solution pH, as well the response of indicator physical-chemical characteristics to key environmental variables (salinity (SP), temperature (T), and pressure). Until recently, the physical-chemical properties …


Archaeology And Seasonality Of Stock Island (8mo2), A Glades-Tradition Village On Key West, Ryan M. Harke Jun 2021

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 …


Past Ice-Ocean Interactions On The Sabrina Coast Shelf, East Antarctica: Deglacial To Recent Paleoenvironmental Insights From Marine Sediments, Kara J. Vadman May 2021

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 …


Investigating The Hydrology Of The Western Greenland Ice Sheet: Spatiotemporal Variability And Implications On Ice-Dynamics, Jessica Z. Mejia Apr 2021

Investigating The Hydrology Of The Western Greenland Ice Sheet: Spatiotemporal Variability And Implications On Ice-Dynamics, Jessica Z. Mejia

USF Tampa Graduate Theses and Dissertations

Since the 1990's the Greenland Ice Sheet (GrIS) has been losing mass at an accelerating rate in response to climatic warming and is currently the largest terrestrial contributor to sea-level rise. While ice sheet models agree the GrIS will continue losing mass throughout the century, there are significant uncertainties associated with future sea-level rise contributions. Predicting the GrIS's response to future climate warming scenarios is limited by gaps in our understanding of the links between ice sheet hydrology and dynamics. Meltwater produced on the ice surface flows within supraglacial streams that deliver it to crevasses or moulins—vertical conduits extending from …


Influence Of Some Climatic Elements On Radon Concentration In Saeva Dupka Cave, Bulgaria, Peter Nojarov, Petar Stefanov, Karel Turek Dec 2020

Influence Of Some Climatic Elements On Radon Concentration In Saeva Dupka Cave, Bulgaria, Peter Nojarov, Petar Stefanov, Karel Turek

International Journal of Speleology

This study reveals the influence of some climatic elements on radon concentration in Saeva Dupka Cave, Bulgaria. The research is based mainly on statistical methods. Radon concentration in the cave is determined by two main mechanisms. The first one is through penetration of radon from soil and rocks around the cave (present all year round, but has leading role during the warm half of the year). The second one is through thermodynamic exchange of air between inside of the cave and outside atmosphere (cold half of the year). Climatic factors that affect radon concentration in the cave are temperatures (air, …


Plio-Pleistocene Antarctic Ice-Ocean Interactions In The Ross Sea, Catherine Prunella Nov 2020

Plio-Pleistocene Antarctic Ice-Ocean Interactions In The Ross Sea, Catherine Prunella

USF Tampa Graduate Theses and Dissertations

Warm, intermediate-depth Southern Ocean waters are implicated in recent Antarctic ice mass loss. Direct observations of Antarctic Ice Sheet (AIS) retreat are temporally limited, necessitating paleoceanographic records of ocean-ice interactions during past warm climate intervals. Deepsea and ice-proximal sediments record orbitally-paced glacial-interglacial fluctuations in AIS volume during the Plio-Pleistocene (last 5 million years; Ma), but the total contribution of the AIS and the role of ocean heat in these fluctuations remain unresolved. To address the response of Antarctica’s ice sheets to changing ocean temperatures during the Plio-Pleistocene, International Ocean Discovery Program (IODP) Expedition 374 recovered sediments from the Ross Sea …