Oceanography Commons^™

Interactions Between Sediment Mechanical Structure And Infaunal Community Structure Following Physical Disturbance, William Cyrus Roger Clemo

Graduate Theses and Dissertations (2019 - present)

Shallow, river-influenced coastal sediments are important for global carbon storage and nutrient cycling and provide a habitat for diverse communities of invertebrates (infauna). Elevated bed shear stress from extreme storms can resuspend, transport, and deposit sediments, disrupting the cohesive structure of muds, and sorting and depositing sand eroded from beaches. These physical disruptions can also resuspend or smother infauna, decreasing abundances and changing community structure. Infaunal activities such as burrowing, tube construction, and feeding can impact sediment structure and stability. However, little is known about how physical disturbance impacts short and long-term sediment habitat suitability and whether disturbance-tolerant infauna influence …

State Of The Fisheries: Status Reports And Aquatic Resources Of Western Australia 2022/23, S.J. Newman, K.G. Santoro, D.J. Gaughan

Status Reports of the Fisheries and Aquatic Resources

Aquatic resources within Western Australia (WA) are in good condition, and this has positioned WA as a global leader in sustainable fisheries management. The sustainable fisheries of WA continue to support our strong economy and regional communities. Nonetheless, the lack of a consistent approach to build in the knowledge of Traditional Owners remains a gap in our longer term fisheries science in Western Australia.

Climate change and climate variability continues to impact fish stocks, challenging our ability to effectively monitor, assess, and manage fish stocks. We are continually working with our stakeholders, and the broader community to be adaptive, responsive, …

The Tidal Prism, Viable Eelgrass Habitat, And The Effects Of Sea Level Rise In Morro Bay, Kaden A. Caliendo

Master's Theses

The tidal prism, or the volume of water exchanged from the sea to an estuary from mean low to mean high tide, influences system hydrodynamics and ecological functioning. Since 1884, the tidal prism in Morro Bay, California has been estimated to be decreasing over time due to sedimentation from upstream practices. What is the current tidal prism in Morro Bay and how will that change with sea level rise? How will eelgrass respond to rising sea levels?

For this study, inexpensive tidal gauges were deployed at four locations in Morro Bay from March to August 2023 to measure spatially varying …

Microscale To Mesoscale Modeling Of The Ocean Under Tropical Cyclones: Effects Of Sea Spray And Surfactants On Tropical Cyclone Intensity And Air-Sea Gas Exchange, Breanna Lynn Cain Vanderplow

All HCAS Student Capstones, Theses, and Dissertations

Tropical cyclone intensity prediction remains a challenge despite computational and observational developments because successful intensity forecasting requires implementing a multitude of atmospheric and oceanic processes. Hurricane Maria 2017 and Hurricane Dorian 2019 serve as prime examples of rapidly intensifying storms that devastated communities in the Caribbean. A lack of understanding and parameterization of crucial physics involved in tropical cyclone intensity in existing forecast models may have led to these and other forecasting errors.

Microscale physical processes at the air-sea interface are a major factor in intensification of tropical cyclones that are often unaccounted for in forecasting models since they are …

Spatial And Temporal Variations Of Microplastics Within Humboldt Bay, California, Isabelle M. Marcus, Tamara B. Barriquand, Rebecca M. Thompson, Bennett C. Hosselkus, Cole T. Hutson, Michael Jacobs, Connor Mcneil, Leah Newton, Stephanie M. Olivarez, Jeffrey Abell

CSU Journal of Sustainability and Climate Change

This study aimed to quantify microplastic (MP) concentration and analyze the spatial and temporal variabilities of the concentrations during the tidal cycle in Humboldt Bay, California. To get an approximation of MP concentration, both water and sediment samples were taken at five different stations, twice during one tidal cycle. Sampling was conducted during two different cruises, on the 19th and 21st of September 2020. The samples were processed in the lab using a density separation procedure and filtration. MP concentrations in the different samples were determined using an average optical microscopy count. Comparison of the water column MP concentrations during …

Tidal Bed Stress Asymmetry And Sediment Transport In Estuaries, Austin Scott Hudson

Dissertations and Theses

Rivers and estuaries provide numerous ecological, economic, and cultural resources. The value of these resources is greatly influenced by sediment transport processes, which can be affected by human activities and climate variability. A key driver of sediment transport in tidal rivers and estuaries is tidal asymmetry of velocity and bed stress, which can manifest from both non-linear tidal interactions and linear interactions among astronomical tidal constituents.

In this study, an analytical framework is developed to examine and describe the dynamics of bed stress asymmetry in semidiurnal, diurnal, and mixed-tide estuaries (Chapter 1). While tidal velocity asymmetry has been previously analyzed, …

Reducing Uncertainty In Sea-Level Rise Prediction: A Spatial-Variability-Aware Approach, Subhankar Ghosh, Shuai An, Arun Sharma, Jayant Gupta, Shashi Shekhar, Aneesh Subramanian

I-GUIDE Forum

Given multi-model ensemble climate projections, the goal is to accurately and reliably predict future sea-level rise while lowering the uncertainty. This problem is important because sea-level rise affects millions of people in coastal communities and beyond due to climate change's impacts on polar ice sheets and the ocean. This problem is challenging due to spatial variability and unknowns such as possible tipping points (e.g., collapse of Greenland or West Antarctic ice-shelf), climate feedback loops (e.g., clouds, permafrost thawing), future policy decisions, and human actions. Most existing climate modeling approaches use the same set of weights globally, during either regression or …

Smart Sounding Table Using Adaptive Neuro-Fuzzy Inference System, Osman Ünal, Nuri Akkaş

Journal of Marine Science and Technology–Taiwan

Marine engineers measure the liquid level (sounding depth) to calculate the volumetric content of a ship's tank. The sounding depth is determined using an ullage pipe located at specific points on the tanks. To estimate the accurate volume of liquid, considering the ship's trim and heel conditions, engineers use a tank table (sounding table) consisting of hundreds of pages. However, this method is time-consuming and lacks intermediate values for sounding depth, trim, and heel. Ship designers recommend to use linear interpolation for intermediate values, yet this process is also time-consuming. This paper proposes the implementation of an Adaptive Neuro-Fuzzy Inference …

Case Study Of Coastal Erosion And Measures At Kezailiao Coast, Taiwan, Tai-Wen Hsu, Yi-Tse Tu, Jen-Yi Chang

Journal of Marine Science and Technology–Taiwan

This paper examines major factors of coastal erosion and measures against beach erosion at Kezailiao Coast, Taiwan. Typical examples of coastal erosion due to natural or man-made factors are reviewed. Case studies of countermeasure for beach erosion are addressed. We further analyze and discuss historical shoreline and coastal cliff recession as a result of the attack of storm surges and waves. The coastline mainly made up of cliffs (2-3m high), made of soft, easily eroded boulder sand and clay. In total, 3km of land have been lost since 1951, including villages and farm buildings. The most important impacts of beach …

Wearable Sensor-Based Walkability Assessment At Ferry Terminal Using Machine Learning: A Case Study Of Mokpo, Korea, Jungyeon Choi, Hwayoung Kim

Journal of Marine Science and Technology–Taiwan

Walkability assessments are becoming more popular, as walking offers numerous health, environmental, and economic benefits to communities. However, previous studies on ferry terminal walkability assessment have been inadequate. This study aimed to develop a wearable sensor system to automatically assess walkability at ferry terminals without conducting surveys. We applied seven machine learning (ML) classifiers to detect different walking environments, including flat ground (FG), downhill slope (DS), uphill slope (US), and uneven surface (UE). The ML models were evaluated across different combinations of classes: 2-class (FG vs. UE), 3-class (U) (FG vs. US vs. UE), 3-class (D) (FG vs. DS vs. …

Application Of Blockchain Technology In Aquaculture Management, Yu-Jen Pan, Hsin-Pei Shieh

Journal of Marine Science and Technology–Taiwan

In recent years, food safety has become a growing concern in Taiwanese society. To ensure efficient management of the supply chain within the L Aquatic Products company, it is imperative to employ reliable technical support in establishing an effective traceability management system. The traceability of products can provide managers with valuable insight into the intricacies of the supply chain. By establishing a dependable food traceability system, brand trust can be strengthened, and consumers can inquire about the movement of aquatic products within the supply chain. Blockchain technology offers features such as traceability, accountability, transparency, reliability, trust, privacy, and security, making …

Production Of Ground Granulated Blast-Furnace Slag Cement: Energy And Carbon Reduction Efficiency Of Cement-Grinding System, Kuan-Hung Lin, Chung-Chia Yang

Journal of Marine Science and Technology–Taiwan

This study used clinker, ground granulated blast-furnace slag (GGBS), and gypsum in a cement-grinding system to produce GGBS cement (GCE). Gypsum was used as the alkaline activator to modify the surface area of GCE and increase its compressive strength. The results revealed that the use of the gypsum activator and the modification of the surface area of GCE effectively increased the formerly inadequate compressive strength of GCE (GGBS > 60%) in the early stage. In addition, energy consumption data were obtained during the production of GCE and Portland cement (PCE) by the cement-grinding system. The calculations concerning the production proportions indicated …

The Uses And Limitations Of Citizen Science For Monitoring The Australian Grey Nurse Shark (Carcharias Taurus) Population, Leah Corckran

Independent Study Project (ISP) Collection

iNaturalist is a citizen science photographic database, which is an underutilized resource in photographic identification research studies. Grey nurse sharks are critically endangered and there is a lack of knowledge regarding the estimated population size, longevity, and interactions with fisheries of this species off the coasts of Australia. To determine how photos submitted to iNaturalist can be used in Carcharias taurus conservation, the photographs were evaluated on a number of criteria including: location, date, visibility of spot patterns, visible sex characteristics, and visible injuries. In total, 814 photographs of grey nurse sharks were obtained from the iNaturalist database. Only 23.2% …

On The Rocks, Below The Rocks: A Study Of Intertidal Life In The Low, Middle And High Zones Of The Puerto Cabuyal – Punta San Clemente Marine Reserve During An El Niño Event, Juliana M. Ferrer

Independent Study Project (ISP) Collection

The rocky intertidal zone is one of the most difficult environments for organisms to survive in due to its harsh biotic and abiotic conditions. As such, it is also one of the best indicators of climate change and an important barrier to beach erosion. This study looked at the rocky intertidal zone of the Puerto Cabuyal-Punta San Clemente Marine Reserve in the Manabí province of Ecuador, with a focus on observing and identifying the organisms found in the area. Data was collected along 30 m transects at varying elevations along the shore using quadrants of two sizes: 50x50 cm for …

Extent Of The 2023 Coral Bleaching Event In The Nargana Region Of Guna Yala, Panama, Brydon Deanna Hollander

Independent Study Project (ISP) Collection

Coral reefs are diverse marine ecosystems that exist in tropical ecosystems all over the world. They provide a myriad of ecological services that are vital for marine organism biodiversity and human coastal communities. A major threat to coral reefs is a rise in sea surface temperature that causes coral bleaching. The effect of a coral bleaching event in Nargana, Guna Yala will be investigated to examine how the health status of coral reef ecosystems are being impacted. To guide these efforts, the extent of coral bleaching will be measured along with whether sea surface temperature (SST), human concentration, and El …

Reef Fish Wariness Behavior: Fish Flight Initiation Distance Mediated By Territoriality And Body Size In Three Reef Sites Off The Western Coast Of Isla Colón, Bocas Del Toro, Panamá, Alina G. Irvine

Independent Study Project (ISP) Collection

Coral reefs are highly productive and diverse underwater ecosystems, providing a variety of environmental services including sand generation, nutrient processing, fish supply, and tourism. However, coral reefs have been increasingly impacted by natural and anthropogenic disturbances, which has negatively affected fish security within their environment. A significant observation is the reduction in evasive behaviors among reef fish in marine reserves compared to those exposed to anthropogenic threats. The present research aims to investigate the factors mediating fish wariness behavior through an exploration of the roles of territoriality and body size on fish flight initiation distance (FID). FID is the distance …

Representations And Realities: Misali Island's Biodiversity In Hybrid Narratives, Justin Ross Whitney

Independent Study Project (ISP) Collection

Marine Protected Areas (MPAs) are complex organisms that ebb and flow between strict and unyielding conservation doctrines often at the cost of community engagement. Misali Island is different. Conceived and advocated for by community members, this organism has navigated a tumultuous tenure of environmental degradation, periods of high and low funding, and a looming tourism presence. On top of these challenges has been a growing fishing community attempting to share in the bounty of this shockingly biodiverse setting. This study sorts through the grey space of Misali Island by applying a hybrid narrative that interfaces the marine context of the …

A New View Of Chlorophyll Dynamics In The Southern Mid-Atlantic Bight From A Two-Year High-Resolution Spray Glider Survey, Francesco Lane

OES Theses and Dissertations

The southern Mid-Atlantic Bight (MAB) near Cape Hatteras, NC, USA, is likely a hotspot for the episodic export of carbon-rich shelf waters to the open ocean. Over a 2 year period, from March 2017 to May 2019, Spray gliders repeatedly occupied transects, along the slope and across the shelf, generating high-resolution chlorophyll fluorescence (fChl) data in the southern MAB. This study implements an fChl calibration method utilizing remotely sensing ocean color as a standard. We validate the method’s utility by demonstrating a reduction in post-calibration cross-mission fChl variability and demonstrating close correspondence between the calibrated fChl data and an in …

Do Microplastics, Vibrio Bacteria, And Warming Water Temperatures Cause Disease In The Northern Star Coral, Astrangia Poculata?, Heather Leigh Sheffey

OES Theses and Dissertations

As marine plastic pollution increases, it becomes imperative to study the effects of microplastics on marine fauna. Marine plastic debris is a vector for disease to marine invertebrates (Lamb et al., 2018; Rotjan et al., 2019). In this context, studies have shown Astrangia poculata will consume microplastics as they do their normal food (Allen et al, 2017; Rotjan et al., 2019). Further, with temperatures increasing worldwide, there is a concern the virulence of disease-causing bacteria will increase (Vezzulli et al., 2015). In a series of manipulative laboratory experiments, this study quantified changes in respiration rates and visual health of Astrangia …

Við Pollurinn: The Effects Of Human-Caused Stimuli On Harbor Seals (Phoca Vitulina) In Ísafjörður, Ella Jorgensen

Independent Study Project (ISP) Collection

Harbor seals are important for the health of Iceland’s marine ecosystems. They are normally seen hauled-out onto land to rest. There are many factors that affect the haul-out patterns of harbor seals including location, season, time of day, tide height, weather, and human-caused stimuli. The presence of human-caused stimuli can also have a negative impact on haul-out patterns and behaviors. The Icelandic harbor seal population is threatened as it has been declining since 1980. Climate change and the rise of tourism in Iceland may be a factor contributing to this decline; and there is a gap in knowledge on the …