Oceanography and Atmospheric Sciences and Meteorology Commons^™

Geohash-Based Arrangement Of Live-Fire Exercise Areas Using Ais, Sang-Lok Yoo, Cho-Young Jung

Journal of Marine Science and Technology–Taiwan

Live-fire exercise (LFX) areas at sea threaten the safety of ships, whereas, and indiscriminately abandoned unexploded bombs threaten the lives of fishermen. No statistical or scientific research has been conducted on the appropriate locations for LFX areas. Therefore, this study proposes a method for effectively arranging the LFX areas at sea that considers the safety of passing ships and national security. First, the proposed method classifies ship tracking data collected in the daytime based on the dawn and dusk times of the civil twilight phase. Second, the method uses a Geohash geocoding process to identify whether an LFX area coincides …

Assessing Hierarchical Corporate Sustainability Transition Practices Under Uncertainty: An Approach In The Port And Shipping Industry In Southeast Asia, Mei-Train Yeh, Feng-Ming Tsai, Taufik Kurrahman

Journal of Marine Science and Technology–Taiwan

The port and shipping industry in Southeast Asia has experienced significant development in response to the increasing demand for maritime logistics and transportation services. However, this expansion has resulted in notable social and environmental impacts. Consequently, it is imperative for both scholars and practitioners to comprehend the concept of corporate sustainability transition (CST), which entails the establishment of shipping operations that effectively balance environmental, social, and economic considerations. Additionally, technologies that are used to facilitate the transition process must be investigated. Several studies have been undertaken to ascertain the attributes pertaining to sustainability transition. Nevertheless, there has been a lack …

Research On Risk Assessment Of Container Operation Process In Ports Considering Functional Areas, Chen-Yu Lin, Ming-Jiu Hwang, Tzu-Heng Yen

Journal of Marine Science and Technology–Taiwan

The risk management of container ports has drawn significant attention recently in part because of recent high-profile accidents in global container ports and in part due to the increasing focus on port safety as a key element in sustainable maritime transportation. This research presented a novel, two-layer container port risk assessment model by partitioning the container port into four areas based on the process of container transportation: loading and unloading, in-port container transportation, storage, and gate areas. Failure mode and effects analysis (FMEA) and quantitative risk analysis modeling were combined for each part of the process to evaluate the risk …

Artificial Intelligence In Prediction Of The Remaining Useful Life Of Wind Turbine Shaft Bearings, Jinsiang Shaw, B.J. Wu

Journal of Marine Science and Technology–Taiwan

Long-term periodic rotation and unstable load changes in wind turbines can cause unexpected damage to high-speed shaft bearings (HSSBs). In this study, after preprocessing of the HSSB vibration signal, four different models for predicting bearing degradation in terms of remaining useful life (RUL) in days were investigated: support vector regression (SVR), convolutional neural networks (CNN), long short-term memory (LSTM), and CNN-LSTM. The experimental results revealed that the CNN achieved the best mean absolute error (MAE), at 0.44 days, based on frequency response plot using the fast Fourier transform (FFT), while that of the CNN-LSTM model predicted using the amplitude profile …

Impact Of Multiple Water Temperature Structures On The Behavioral Pattern Of Chum Salmon (Oncorhynchus Keta) On The Coast Of The Shiretoko Peninsula, Xinyi Li, Hiroshi Yamaguchi, Hokuto Shirakawa, Kenji Minami, Nobuhiko Sato, Yanhui Zhu, Yasuyuki Miyakoshi, Kazushi Miyashita

Journal of Marine Science and Technology–Taiwan

During the migration of chum salmon (Oncorhynchus keta) towards the Shiretoko Peninsula in Hokkaido, Japan, the convergence of coastal currents results in the formation of intricate water temperature structures. However, the impact of this phenomenon on the behavioral tendencies of chum salmon remains largely unexplored. In 2012 and 2013, we conducted a study to document the vertical water temperature profiles and uninterrupted swimming patterns of homing chum salmon in the coastal waters surrounding the Shiretoko Peninsula. The results indicated that chum salmon exhibited a preference for avoiding thermoclines characterized by rapidly decreasing water temperatures. They were predominantly observed swimming either …

Research On The Collision Risk Of Ships Off Keelung Based On Ais Data, Shih-Tzung Chen, Ming-Feng Yang, Sheng-Long Kao, Mengru Tu, Jun-Yuan Kuo, Yen-Ting Chao, Huang-Kai Hsu

Journal of Marine Science and Technology–Taiwan

In previous literature, several computational methods have been proposed to analyze collision risks for vessels navigating at sea, most of which rely on the calculation of DCPA and TCPA between two vessels. However, this study adopts an enhanced version of the Vessel Conflict Ranking Operator (VCRO) to assess vessel collision risks. This approach not only considers the relative distance and relative velocity between two vessels but also takes their relative aspect into account. This methodology was applied to real-world vessels’ dynamic data collected through AIS. From a near-collision perspective, it identifies high-risk areas near Keelung water where commercial vessels and …

Cooling Performance Analysis For Mobile Vehicles By Thermal Resistance Network, Chia-An Yang, Jung-Chang Wang, Pi-Hsia Yen

Journal of Marine Science and Technology–Taiwan

This paper used CFD software to simulate the cooling situation of the engine space of a mobile vehicle. We used thermal resistance network diagram to calculate the heat flux at each position of the power system, and discussed the CFD simulation results. The error between the simulation results and the experiment was 10.07%. The thermal resistance network diagram proposed in this paper can reduce the time for numerical simulation by evaluate the heat flux at each position of the power system.

Microbial Community And Genome Structure In Coastal Seawater From A Commercial Port And Nearby Offshore Island In Northern Taiwan, Chi-Yu Shih, Ching-Hsiang Chin, Shiow-Yi Chen, Chun-Ru Hsu, Lee-Kuo Kan, Wen-Shyong Tzou

Journal of Marine Science and Technology–Taiwan

The pollution stemming from the use of petroleum by boats, the presence of deceased marine life, hazardous chemicals, and wastewater is a major issue in human-made commercial ports. This pollution poses a considerable challenge to the diverse organisms inhabiting the seawater. To comprehend the impact of this pollution on the microbiome, we conducted a study in which we collected surface water samples from a commercial port called Keelung Port, as well as a nearby offshore island known as Keelung Islet. These locations are situated in northern Taiwan, along the Northwestern Pacific Ocean. Through the use of whole-metagenome shotgun sequencing, we …

2023 January - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

Seagrass Posidonia Escarpments Support High Diversity And Biomass Of Rocky Reef Fishes, Oscar Serrano Gras, Karina Inostroza, Glenn Hyndes, Alan M. Friedlander, Eduard Serrano, Caitlin Rae, Enric Ballesteros

Research outputs 2022 to 2026

Although seagrass meadows form a relatively homogenous habitat, escarpments, which form three-dimensional structures and originate from the erosion of seagrass peat, can provide important habitat for reef fishes. Here, we compare fish assemblages and habitat structural complexity among seagrass Posidonia australis escarpments and canopies, as well as limestone reef habitats, to understand the role of seagrass escarpments as reef fish habitat in Shark Bay, Western Australia. The total number of fish species, fish biomass, and top predator biomass were significantly higher in seagrass escarpments and reef habitats than in seagrass canopies due to lower habitat structural complexity and thus becoming …

Decline Of Seagrass (Posidonia Oceanica) Production Over Two Decades In The Face Of Warming Of The Eastern Mediterranean Sea, Victoria Litsi-Mizan, Pavlos T. Efthymiadis, Vasilis Gerakaris, Oscar Serrano, Manolis Tsapakis, Eugenia T. Apostolaki

Research outputs 2022 to 2026

* The response of Posidonia oceanica meadows to global warming of the Eastern Mediterranean Sea, where the increase in sea surface temperature (SST) is particularly severe, is poorly investigated. * Here, we reconstructed the long-term P. oceanica production in 60 meadows along the Greek Seas over two decades (1997–2018), using lepidochronology. We determined the effect of warming on production by reconstructing the annual and maximum (i.e. August) SST, considering the role of other production drivers related to water quality (i.e. Chla, suspended particulate matter, Secchi depth). * Grand mean (±SE) production across all sites and the study period was 48 …

Impacts Of Synoptic-Scale Dynamics On Cloud Properties And Radiation In High Southern Latitudes, Tyler R. Barone

Master's Theses

Predicting future climate change relies on accurate representations of the earth’s surface radiation budget. Complex interactions between large-scale dynamical conditions (e.g., low-pressure systems) and microscale processes (e.g., cloud properties) are key contributors to energy budget biases within global climate models. Proper estimation of cloud microscale processes and their responses to synoptic-scale dynamics will greatly improve the accuracy of the simulated energy balance within global climate models. High-latitudinal clouds have significant influences on the Earth’s radiative balance. We examined observations from two field campaigns at Macquarie Island in the Southern Ocean and McMurdo Station in Antarctica. Two global climate models are …

Daily Synoptic-Scale Influences On Weather-Dependent Renewable Energy Supply And Demand In Hypothetical Fully Electrified North American Interconnections, Howard Tang

Master's Theses

Energy grids around the world are becoming increasingly penetrated by renewable energy sources, resulting in progressively variable energy generation. This study aims to provide a fundamental basis for observing atmospheric conditions in relation to weather-dependent renewable energy supply, where daily synoptic-scale influences are considered in hypothetical fully electrified North American interconnections. Three renewable energy types – 100% wind energy, 100% solar energy, and a 50-50 split of wind and solar energy – are scaled to meet weather-driven energy demand on average in three interconnections, namely the Western Interconnection, the Eastern Interconnection, and a hypothetical combined interconnection composed of the Western, …

Cloud Phase Distribution At A Global-Scale And The Governing Factors Using Satellite And In-Situ Airborne Observations, Dao Wang

Master's Theses

Cloud thermodynamic phase distributions play a crucial role in accurately representing cloud radiative effects and feedback in a changing climate. The partitioning of cloud thermodynamic phases (ice, liquid, and mixed phase) significantly influences Earth's surface temperature and its ability to mitigate the impact of global warming. Satellite-based cloud phase data are frequently used for the evaluation of global climate models, yet validation of them against in-situ observations is still lacking. This study examines global cloud phase distributions and their determinant factors by validating three satellite-based cloud phase products against an extensive in-situ airborne dataset. CALIPSO exhibits the most similar ice …

Marine Heatwaves Modulate The Genotypic And Physiological Responses Of Reef-Building Corals To Subsequent Heat Stress, Kristen T. Brown, Amatzia Genin, Matheus A. Mello-Athayde, Ellie Bergstrom, Adriana Campili, Aaron Chai, Sophie G. Dove, Maureen Ho, Devin Rowell, Eugenia M. Sampayo, Veronica Z. Radice

Biological Sciences Faculty Publications

Back-to-back marine heatwaves in 2016 and 2017 resulted in severe coral bleaching and mortality across the Great Barrier Reef (GBR). Encouragingly, some corals that survived these events exhibit increased bleaching resistance and may represent thermally tolerant populations that can better cope with ocean warming. Using the GBR as a natural laboratory, we investigated whether a history of minimal (Heron Island) or severe (Lizard Island) coral bleaching in 2016 and 2017 equates to stress tolerance in a successive heatwave (2020). We examined the genetic diversity, physiological performance, and trophic plasticity of juvenile (<10 cm) and adult (>25 cm) corals of two common genera ( …

Levels Of Autotrophy And Heterotrophy In Mesophotic Corals Near The End Photic Zone, Amy Carmignani, Veronica Z. Radice, Kathryn M. Mcmahon, Alex I. Holman, Karen Miller, Kliti Grice, Zoe Richards

Biological Sciences Faculty Publications

Mesophotic corals live at ~30-150 m depth and can sustain metabolic processes under light-limited conditions by enhancing autotrophy through specialized photoadaptations or increasing heterotrophic nutrient acquisition. These acclimatory processes are often species-specific, however mesophotic ecosystems are largely unexplored and acclimation limits for most species are unknown. This study examined mesophotic coral ecosystems using a remotely operated vehicle (Ashmore Reef, Western Australia at 40–75m depth) to investigate the trophic ecology of five species of scleractinian coral (from genera Leptoseris, Pachyseris, and Craterastrea) using stable isotope analyses (δ¹³C and δ¹⁵N) of host and symbiont tissues …

Climate And Health: Impact Of Climate Education On Nursing Student Knowledge, Confidence, And Intent To Act, Beth Tremblay, Janice Hawkins

Ellmer School of Nursing Faculty Publications

Background: Because climate change negatively impacts human health, nurses need skills to mitigate climate change and nurse educators need effective educational strategies to teach climate change content in undergraduate nursing programs. To address this need, we embedded an energy efficiency treasure hunt and Climate for Health Ambassador Training into our prelicensure nursing curricula.

Purpose: To evaluate the impact of these educational activities on self-reported knowledge, confidence, and intent to engage in climate action.

Methods: A quasi-experimental one-group posttest design examined the effectiveness of 2 educational interventions on increasing knowledge, confidence, and intent to engage in climate action. A convenience sample …

Quantifying The Economic Costs Of Global Warming, Christopher W. Callahan

Dartmouth College Ph.D Dissertations

Climate change poses a threat to the well-being of people across the globe. Rising global temperatures will increase the frequency and magnitude of extreme climate events, threatening the lives and livelihoods of vulnerable people. Yet the magnitude and persistence of these economic impacts are poorly understood, making it difficult both to design equitable mitigation and adaptation strategies and to hold emitters accountable for the impacts of their emissions. In this thesis, I combine methods from detection and attribution, climate projection, and causal inference to understand the global economic consequences of past and future climate change. I show that two extreme …

Alternatives To Reducing Aviation Fuel-Burn With Technology: Fully Electric Autonomous Taxibot, Denzil Neo

Student Works

Aircraft taxiing operations in the aerodrome were identified to consume the most jet fuel apart from the cruise phase of the flight. This was also well supported by various research associating taxi operations at large, congested airports, with high jet fuel consumption, high carbon emissions, and noise pollution. Existing literature recognised the potential to address the environmental issues of aerodrome taxi operations by operating External or Onboard Aircraft Ground Propulsion Systems (AGPS). Designed to power aircraft with sources other than their main engines, external Aircraft Ground Power Systems (AGPS) have shown the potential to significantly cut jet fuel consumption and …

Using Micro Satellites To Assess The Impact Of Algae Growth On Global Warming, Hursh, Vanessa

Student Works

Data gathered from microsatellites can inform policymakers and environmental agencies about the impact of algae on global warming. It can guide the development of strategies to mitigate or harness the potential benefits of algae growth.

Comparison Of Permafrost Thaw-Related Changes To Hydrological Response And Land Cover In Subarctic Peatland-Dominated Landscapes, Mikhail Mack

Theses and Dissertations (Comprehensive)

The hydrological implications of discontinuous permafrost thaw in peatland-dominated basins are not well understood. While there is evidence suggesting that permafrost-thaw-driven land cover change increases annual runoff and the runoff ratio in the Taiga Plains of northwestern Canada, few studies have evaluated the impact on small to medium-sized basins (< 10⁵ km²) outside this ecoregion. Here, we assess runoff, runoff ratio, and precipitation trends for 34 peatland-dominated basins, of which 28 are in the discontinuous and sporadic permafrost zones and 6 in adjacent permafrost-free environments. We calculated annual and monthly trends between 1970 and 2016 using the Mann-Kendall …

Spatial And Temporal Characteristics Of Historical Surface Climate Over The Northwest Territories, Canada, Bhaleka D. Persaud

Theses and Dissertations (Comprehensive)

Climate change is putting many of the Northwest Territories (NWT) ecosystems, its people and animal populations at risk due to accelerated warming, permafrost thaw, and changing precipitation regimes. As the NWT continues to warm, at disproportionately higher rates when compared to the rest of Canada, threats to the stability of NWT’s ecosystems are expected to increase. Consequently, understanding how climate warming has changed historically and its implications on natural ecosystems requires point-to-region-specific, long-term climatic data to elucidate important drivers of observed changes relevant to decision makers at community, Indigenous, Territorial and Federal government levels. However, in situ climate data are …

Atmospheric Meteorological Effects On Forecasting Daily Lightning Occurrence At Cape Canaveral Space Force Station, Jon Saul, Torrey J. Wagner, Eric G. Mbonimpa, Brent T. Langhals

Faculty Publications

As the Cape Canaveral Space Force Station and Kennedy Space Center increase their launch rate, any process that could assist in the automation of the currently-manual lightning forecast would be valuable. This work examines the possibility of machine-learning assistance with the daily lighting forecast which is produced by the 45th Weather Squadron. A dataset consisting of 34 lightning, pressure, temperature and windspeed measurements taken from 334 daily weather balloon (rawinsonde) launches in the timeframe 2012-2021 was examined. Models were created using recursive feature elimination on logistic regression and XGClassifier algorithms, as well as Bayesian and bandit optimization of neural network …

The Behavior Of Partially Coherent Twisted Space-Time Beams In Atmospheric Turbulence, Milo W. Hyde Iv

Faculty Publications

We study how atmospheric turbulence affects twisted space-time beams, which are non-stationary random optical fields whose space and time dimensions are coupled with a stochastic twist. Applying the extended Huygens–Fresnel principle, we derive the mutual coherence function of a twisted space-time beam after propagating a distance z through atmospheric turbulence of arbitrary strength. We specialize the result to derive the ensemble-averaged irradiance and discuss how turbulence affects the beam’s spatial size, pulse width, and space-time twist. Lastly, we generate, in simulation, twisted space-time beam field realizations and propagate them through atmospheric phase screens to validate our analysis.

Combustion Soot Nanoparticles: Mechanism Of Restructuring And Mechanical Properties, Ali Hasani

Dissertations

Soot, a product of incomplete combustion of fossil fuels, is a global warming agent. The effect of soot particles on climate depends on their morphology. Freshly released soot particles are fractal lacey aggregates, but they often appear collapsed in atmospheric samples collected away from emission sources. A body of work has concluded that the collapse is caused by liquid shells when they form by vapor condensation around soot aggregates. However, some recent studies argue that soot remains fractal even when engulfed by the shells, collapsing only when the shells evaporate. To reconcile this disagreement, the effects of the condensation and …

Monitoring Climate Change With Machine Learning And Uncertainty Quantification, Firas Gerges

Dissertations

The impact of climate change on the environment has become increasingly visible today. One important topic in climate change monitoring is to forecast future climate events, which relies on long-term prediction of climate variables at a local regional scale. This topic is crucial for disaster risk management and for resolving climate change at the local level. General Circulation Models (GCMs) allow for the simulation of several climate variables, decades into the future. GCM simulations, however, are at a global large scale and are too coarse to monitor climate change at the local small scale. This dissertation explores new machine learning …

2022 - Tennessee Annual Climate Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

Spatiotemporal Variability Of Drought And Its Relationships To Enso And Iod Indices In Somaliland, Mohamed S Bile, Paul Ts Limbu

Tanzania Journal of Science

Drought is one of Somaliland’s most prevalent natural hazards, causing serious socioeconomic and environmental harm. This study investigated the spatial and temporal variability of drought and its relationships with El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) indices using the Standardized Evapotranspiration Index (SPEI) from 1981 to 2020. The Mann-Kendall trend test and Sen's slope estimator were used to assess the trends of annual and seasonal SPEI time series. The Empirical Orthogonal Function (EOF) was employed to examine the dominant modes of the SPEI series, and Pearson and partial correlation analyses were performed to investigate the associations between …

Historical Tsunami Observability For Izu–Bonin–Mariana Sources, Walter Szeliga, Rachelle Reisinger, Breanyn T. Macinnes

Geological Sciences Faculty Scholarship

The Izu–Bonin–Mariana Subduction System (IBM) is one of the longest subduction zones in the world with no instrumental history of shallow focus, great earthquakes (Mw > 8). Over the last 50 years, researchers have speculated on the reason for the absence of large magnitude, shallow seismicity on this plate interface, exploring factors from plate age to convergence rate. We approach the question from a different point of view: what if the IBM has hosted great earthquakes and no documentable evidence was left? To address the question of observability, we model expected tsunami wave heights from nine great earthquake scenarios on the …

2022 December 29 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.