Tidal Phenomena Research Articles

Mean sea level, tidal components and surges in Guanabara Bay (Rio de Janeiro) from 1990 to 2021

AbstractGuanabara Bay, located in the Metropolitan Region of Rio de Janeiro, one of the largest urban coastal areas in the Southern Hemisphere, is subject to intense maritime traffic due to the presence of several ports. These facilities are affected by sea level fluctuations, influenced by atmospheric and astronomical forces, which motivates synoptic and climatological analysis, including meteorological and astronomical tidal phenomena. This study aimed to assess the evolution of tidal components and the relative mean sea level (MSL) between 1990 and 2021, as well as the atmospheric influence on extreme meteorological tide events, in which the MSL exceeded ±2 and ±3 (±29.98 and ±44.97 cm) standard deviations. The results have shown that, albeit small, the main tidal components (, , , , , , and ) indicated positive trends in the increase of amplitude and phase, despite the small quantities. For the relative MSL, an increase of 0.30 cm·year−1 was observed in agreement with estimates from global series from satellite altimeters and climate model predictions. Pressure and wind field analyses led to the identification of seasonal variability and the pattern of evolution of atmospheric systems associated with extreme events. In the case of positive surges, very intense winds from the SW, extending along the S/SE Brazilian coast, are caused by the presence of a high‐pressure centre over the continent and low‐pressure centres over the ocean, leading to water piling up. In turn, negative surges are caused by the presence of an anticyclone over the ocean, generating NE winds parallel to the coast of Rio de Janeiro, inducing Ekman transport and lowering the sea level. Therefore, the extreme sea level events in the Guanabara Bay are not triggered by local forces, but rather depend on the temporal persistence and direction of winds along the S/SE Brazilian coast.

Effect of background wind and dissipation processes on the diurnal component of atmospheric solar tides

The radiation coming from the Sun heats the Earth’s atmosphere and generates atmospheric tides. In this paper, we model atmospheric tides in the presence of background wind and dissipation processes and investigate their effects. The equations for tidal oscillations of wind and temperature in the atmosphere encompass factors such as background wind, temperature profile, and background composition including ozone, carbon dioxide, hydro-magnetic interactions, Newtonian cooling, eddy, and molecular diffusion. These components interact to define the behavior of tidal phenomena comprehensively. Thermal forcing processes include the insolation absorption of H2O in the troposphere, O3 in the stratosphere, and a contribution from O2 absorption in the thermosphere. The method of solution for the equations is outlined for the solar diurnal tides during the March equinox by considering all these dissipation processes and the background wind. The obtained results are in good agreement with the Global Scale Wave Model (GSWM-00). It is found that the background wind plays significant role in affecting the horizontal wind oscillations below 100 km. At higher altitudes (100–200 km), the background wind, ion drag force, divergence of momentum, and heat fluxes due to molecular and eddy diffusion have a considerable role in affecting the zonal and meridional winds.

Occurrence of microplastics and ecological risk assessment during tidal changes in the Chao Phraya River estuary, Thailand

River estuaries are specific transition zones that connect coastal and terrestrial environments and are recognized as primary conveyors for land-derived plastics to open oceans. The present study is the first to investigate tidal effects on microplastics (MPs) in the Chao Phraya River estuary. MPs (16–5000 μm) were collected from the water column during the changes in tidal current in order to analyze abundance, characteristics, and ecological risk. The abundance of MPs varied from 1.37 to 4.51 pieces/L and an average of 4.0 ± 3.8 pieces/L were found during the tidal cycle, which implied moderate to relatively high contamination when compared to other estuaries. Moreover, the average abundance of MPs during the low tide period was comparatively higher than that in other tidal phenomena. Morphological characteristics revealed that shape of fragments, shade of blue, size of 16–100 μm and PTFE is dominant in the MPs. The pollution load index (PLICPRE) was 5.98, which denoted that the Chao Phraya River estuary is polluted with MPs at a low contamination level. In contrast, the risk index (RICPRE) of MPs in the water column during the tidal cycle was 318.8, which indicated that the estuarine ecosystem of the Chao Phraya River is under considerable risk. In the present study, an ecological risk assessment was conducted for the Chao Phraya River estuary, which provides basic reference data for the management of pollution control related to MPs in the Chao Phraya River basin.

PENGEMBANGAN ARDUINO DATA LOGGER MENGGUNAKAN TDR H3CR UNTUK SIMULATOR PASANG SURUT

Tides, crucial natural phenomena, significantly impact various aspects of life. Recognizing their importance, this study presents the development of a tidal simulator leveraging Arduino data logging and TDR H3CR technology. The simulator aims to mimic tidal processes, crucial for educational and research purposes. Traditional methods of acquiring tidal data are time-consuming and expensive. Thus, a simulator proves advantageous in reducing research time and costs. At Raja Ali Haji Maritime University, a tidal simulation model exists but with manual operation and limited data capture capabilities. To address these limitations, this study designed a new simulator utilizing H3CR, DC Water Pump, and DC Selenoid Valve for automated tidal circulation. The research method involved system design, component integration, and laboratory experiments. Calibration of components like the ultrasonic sensor HC-SR04 ensured accurate data collection. The overall system experiment validated the simulator's functionality, demonstrating its ability to replicate tidal processes effectively. Results indicated that the simulator produced tidal patterns resembling sinusoidal waves, with slight noise attributed to sensor limitations. The designed simulator serves as an efficient learning tool for understanding tidal phenomena, exhibiting comparable results to natural tidal data. This study contributes to the advancement of tidal simulation technology, offering a cost-effective and accessible solution for educational and research purposes.

Relationship Between Earth-Moon Distance and Tides

For residents and fishermen in coastal cities, tidal phenomena are a dangerous existence, and for tidal power stations, tidal phenomena will bring clean energy to them. For the formation of tidal phenomena, the most closely related is the distance between the Earth and the Moon. Therefore, this paper collects the tides and Earth-Moon records in New York in 2022, and performs data visualization operations on the data, and uses STL (Seasonal Decomposition of Time Series), MSTL (Multiple Seasonal-Trend Decomposition using Loess) models to predict, so as to explore the concern between the Earth-Moon distance and tides. Monthly seasonality is found from our analysis as well as the general trend which follows the research results regarding to earth moon distance variation. The results show that when the Earth is close enough in the Moon, the tides are more pronounced.

The influence of the Sun, Moon and Earth Tides

Tidal phenomena, a ubiquitous spectacle along coastlines, have captivated human curiosity for centuries. It can be involved in some small activities like fishing on the sea. Also, some big activities like the prediction of the position of the Earth should take the consideration of tides. This paper is aimed to have a summary of the formation and the principles of tides. Then, according to the essential theory, some applications are discussed based on the fields of astrology, geography, and clean energy. The principles of these applications are summarized and concluded into some useful information. The information that people derive from tides is a significant amount which can help humans make more efficient methods for the prediction of some phenomena like earthquakes and the movement of moons. As a result, The value of tides is still a potential topic that can help human progress in human beings.

Некоторые оценки тяжелых ледовых условий (сжатий) в Печорском море по данным наблюдений и моделирования (моделирование и анализ)

The work continues the study focused on the analysis of the severe ice conditions’ formation in the Pechora Sea during navigation in 2003 and 2018 (published in vol.12, no.4, 2022). Using a numerical model, the authors reproduce the dynamics and some elements of the morphometry of the ice cover during the indicated ice seasons. Thus, they reveal that the significant ice pressure (100—150 kPa and more) is caused by the strong on-shore wind, while the ice pressure related to the tidal phenomena have the predominant value at the weak winds. The tidal ice pressure occurs permanently and regularly, and varies mainly within the range of 10—50 kPa. The contribution of ice hummocks to the total ice volume becomes significant when strong ice pressure happens at the background of high ice thickness (close to the seasonal maximum, i.e. more than 60—70 cm). With small ice thicknesses, even strong ice pressure, as a rule, does not lead to a significant increase in the equivalent thickness of hummocks.

DEVELOPMENT OF SUSTAINABLE TOURISM INSTRUMENTS FOR ECOLOGICAL RESILIENCE IN PARI ISLAND, DKI JAKARTA

<p><span>The research objective is to develop an instrument for assessing sustainable tourism in the context of ecological resilience in Pari Island, DKI Jakarta. This study uses research and development methods through the ADDIE model approach. The research sample includes potential and factual coral reef areas for tourism in Pari Island. The results of the study concluded that the validation of important instruments includes: (1) natural/biological criteria, namely unique and beautiful coral reefs, quite unique tidal phenomena, endemic flora and fauna such as seagrass and fish habitat, as well as other aquatic biota, ease of observing aquatic biota, opportunities for trekking, snorkeling, etc. as well as the support of comfortable temperature and humidity, normal rainfall conditions, as well as well-managed household industrial waste; and (2) Physical environmental criteria such as dominant beaches, controlled coastal land conversion rate and protected from pollution, ease of utilizing rocky beaches for friendly productive activities. The environment, such as maintaining fish, marine tourism, and others as well as the existence of a map of the distribution of coral reefs that accurately depicts local potential as well as information related to the low risk of natural disasters (landslides, floods, tsunamis). </span></p>

Influence of tidal phenomena on nutrient variations in water column of the Chao Phraya River estuary

Influence of tidal phenomena on nutrient variations in water column of the Chao Phraya River estuary

The Structure of the Zooplankton Communities in Sukhoe More Bay, Southeastern White Sea

This paper presents the results of our investigation of the zooplankton communities from Sukhoe More Bay, located in the southeastern part of Dvina Bay of the White Sea, in July−August, 2018. The species composition, quantitative characteristics and spatial distribution of zooplankton were studied. The zooplankton communities are composed of 34 species of hydrobionts. Copepods were the dominant group in the entire study area. The zooplankton communities were characterized by high quantitative indicators. Juvenile stages of copepods were a significant contribution to the formation of the total number of zoocenoses. During high water level, the abundance of zooplankton was 37 000 ind./m3, biomass, 0.6 g/m3 (wet weight). During low water level these parameters were 210 000 ind./m3 and 1.7 g/m3 (wet weight), respectively. The structure, abundance and spatial distribution of zooplankton in the bay are determined by the morphometric features of the reservoir (shallow water), the influence of a complex of environmental factors (temperature and salinity), as well as tidal phenomena.

How Should Soundscape Optimization from Perceived Soundscape Elements in Urban Forests by the Riverside Be Performed?

Urban forests by the riverside are important habitats for various animals and contribute various soundscapes for citizens. Unfortunately, urban forests are exposed to the influence of riverside traffic noises from freeways. This study aims to explore the spatial and temporal variation of soundscape, conduct soundscape optimization for multiple parameters, and find a balance and its interval of soundscape elements through optimizing a soundscape map. Questionnaires and measuring equipment were used to gather soundscape information in an urban forested area in Fuzhou, China. Diurnal variations and soundscape mapping were used to analyze spatial and psychophysical relationships between soundscape drivers. We then conducted optimization for a soundscape map, which included normalization, critical value determination, target interval of optimal SPL determination, and modification of SPL and mapping. Our findings suggest that biological activities and natural phenomena are potential drivers for diurnal variation of soundscapes, especially tidal phenomena contributing water and shipping soundscapes. Our results also suggest that all the high values of perceived soundscapes were found at the southwest corner of the study area, which includes both riverside and urban forest elements. Furthermore, we suggest combining both optimal soundscape and SPL correction maps to aid in sustainable design in urban forests. This can contribute to the understanding and methodology of soundscape map optimization in urban forests when proposing suitable design plans and conservation of territorial sound.

Analysis of the level of community resilience to tidal flood disaster in Karangagung Village, Palang District, Tuban Regency, East Java

Tidal floods are inundations of water on the coastal plain due to high tide. Tidal floods are caused by tidal phenomena and excessive sea water intrusion due to rain. The level of resilience of coastal communities needs to be studied in order to minimize the impact and obtain recommendations for increasing the resilience of coastal communities to the threat of disasters. The aim of this research is to determine the level of community resilience to tidal floods in Karangagung Village, Palang District, Tuban Regency, East Java. The level of community resilience to tidal floods was analyzed using the Coastal Community Resilience (CCR) method. The results of the level of community resilience in facing tidal floods in Karangagung Village, Palang District, Tuban Regency have a value of 3.96 in the high category.

Finite-Sized Orbiter’s Motion around the Natural Moons of Planets with Slow-Variable Eccentricity of Their Orbit in ER3BP

This article is devoted to the study of the stability of movement of a satellite of finite size around the natural satellites of the planets in the solar system, using the new concept of ER3BP with variable eccentricity. This concept was introduced earlier for the variable spin state of a secondary planet correlated implicitly to the motion of the satellite for its trapped orbit near the secondary planet (which is involved in the Kepler duet “Sun-planet”). But it is of real interest to explore another kind of this problem, plane ER3BP “planet-moon-satellite”. Here, we consider two primary celestial bodies, a planet and a moon, the latter revolves around its common barycenter in a quasi-elliptical orbit in a fixed plane (invariable plane) around the planet with a slowly varying eccentricity on a large time scale due to tidal phenomena. This study presents both new theoretical and numerical results for various cases of the “planet-moon-satellite” trio.

Numeričko modeliranje hidrodinamičke izvedbe na poroznom kosom tipu plutajućeg lukobrana

A breakwater is a coastal building that aims to break up or withstand wave energy that enters the beach so that the characteristics of the incoming waves are by calculations and can reduce abrasion on the shoreline. Designing a floating breakwater is very complicated because it depends on many aspects. These fundamental aspects depend on each other, so if one of these aspects changes, the integrity of the floating breakwater structure will also change. One of these aspects is the magnitude of the transmission and reflection coefficients generated by the floating breakwater. This research will study the hydrodynamic performance of floating breakwater due to variations in slope and porosity in reducing and reflecting waves with computational fluid dynamics (CFD). The slope-porous floating breakwater dimension is based on previous experimental data, including a constant water depth of 0.75 m, a wave height of 0.05 - 0.125 m, and a wave period of 1.1 - 2 sec on regular waves. The results of the numerical model validation and experiments on all variations of the floating breakwater model are quite good, which is less than 10% for both wave transmission and reflection. Analysis of the influence of changes in the mooring line angle, the simulation is carried out at an angle of 30 deg to 90 deg and produces an average transmission coefficient of 0.79 and a reflection of 0.21. While the effect of changes in water level elevation (0.85 m, 0.75 m, and 0.65 m) gives a reasonably significant average transmission coefficient of 0.85 and a reflection of 0.13. The mooring line angle will be gentler at high tide, and the transmission and reflection coefficients will be higher. However, the mooring line will loosen at low tide, causing the structure to move more freely and eliminating the function of the floating breakwater itself so that the tidal phenomenon becomes a challenge for coastal experts in designing structures to produce effective and efficient hydrodynamic performance.

The Development of Tidal Power System Can be Installed in Existing Dykes -The Open Channel Experimental Verification

As problems such as difficulties in securing stable energy resources and global warming due to the emission of greenhouse gases due to the use of fossil fuels have emerged, interest in the development of renewable energy is increasing. Since the tidal phenomenon has a regularity that occurs regularly with a certain period, it is possible to predict accurately in advance, which has a advantage in terms of energy recovery. Therefore, various methods have been devised to utilize the tide as an energy source. Tidal power using barrages is a representative method that is widely operated, but the promotion of tidal power generation projects is being delayed or stopped due to the decrease in the level of water in the tidal basin, changes in water quality and in the ecosystem. In this study, a field experiment was conducted to develop and verify the performance of a tidal power device applicable to sea areas where dykes are already installed. As a result of carrying out four cases of experiments using two water tanks, pipe lines, open channels, weirs, and water turbine and generator, the possibility of developing a power generation system capable of 10 kW output or more and 60% efficiency or more was confirmed. These research results can be used for small-scale tidal power by utilizing the existing dykes.

Time Segmentation-Based Hybrid Caching in 5G-ICN Bearer Network

The fifth-generation communication technology (5G) and information-centric networks (ICNs) are acquiring more and more attention. Cache plays a significant part in the 5G-ICN architecture that the industry has suggested. 5G mobile terminals switch between different base stations quickly, creating a significant amount of traffic and a significant amount of network latency. This brings great challenges to 5G-ICN mobile cache. It appears urgent to improve the cache placement strategy. This paper suggests a hybrid caching strategy called time segmentation-based hybrid caching (TSBC) strategy, based on the 5G-ICN bearer network infrastructure. A base station’s access frequency can change throughout the course of the day due to the “tidal phenomena” of mobile networks. To distinguish the access frequency, we split each day into periods of high and low liquidity. To maintain the diversity of cache copies during periods of high liquidity, we replace the path’s least-used cache copy. We determine the cache value of each node in the path and make caching decisions during periods of low liquidity to make sure users can access the content they are most interested in quickly. The simulation results demonstrate that the proposed strategy has a positive impact on both latency and the cache hit ratio.

Low-carbon Transformation of Nankai Campus Based on Energy Audits Comprehensive utilization of New Energy

The existing campus has a large building area, a low level of energy saving, less renewable energy utilization, higher energy consumption, and obvious energy-saving space. Based on the energy audit of Nankai University, this paper proposes a low-carbon campus transformation technology system combining building energy saving, clean heat supply and distributed photovoltaic in view of its problems such as high municipal heating energy consumption, low comfort, high electricity bill, and tight electricity consumption. Because the campus has both winter holidays and there is tidal phenomenon in teaching buildings and dormitory buildings, etc., the heating demand is reduced, so its heating and energy-saving space is large. At the same time, the number of campus building floors is low, the roof is conducive to the installation of photovoltaic, it is estimated that the annual power generation of rooftop photovoltaic installation can reach more than 70% of the campus electricity consumption, combined with energy-saving transformation and smart energy management, it is easy to achieve its low-carbon goals.

Computational Fluid Dynamics-based Simulation and Design of a Horizontal Tidal Turbine System

Tidal phenomena, the rhythmic rise and fall of sea waters due to gravitational forces among celestial bodies like the Sun, Earth, and moon, offer a dependable source of renewable energy. Tidal energy, with its predictability and high energy density, is an attractive sustainable option. Tapping into this energy requires a specialized device, the tidal turbine, where the rotor plays a vital role. The rotor converts the kinetic energy of incoming tides into useful mechanical energy, evaluated through thrust, torque, and power efficiency. This study focuses on designing a horizontal tidal turbine using a three-dimensional Computational Fluid Dynamics (CFD) model with ANSYS Fluent software. Input parameters are based on real-world measurements of the average current velocity of 1 m/s obtained using Acoustic Doppler Current Profiler (ADCP). The paper serves two purposes: validating the applied design approach and analysing crucial design factors. By confirming design compatibility and assessing factor properties, the research contributes to optimizing tidal turbine efficiency and its feasibility as a sustainable energy source.

An Intelligent Rebalance System for Tidal Phenomenon of Dockless Bicycle-Sharing

With the advantages of flexible parking locations and convenient cycling, Dockless Bicycle-sharing (DBS) has become increasingly popular worldwide. However, with the massive increase of DBSs and electric fences, DBS systems face several challenges: (1) the hardness of identifying the DBS tidal zones; (2) the difficulty of accurately evaluating and identifying overload fences; (3) the issues of rebalancing DBS in time. To deal with these challenges, we propose a Dockless Bicycle-sharing Dynamic Rebalance (DBSDR) system to dynamically provide the optimal bicycle guidance for the DBS network. The DBSDR system contains three modules: DBS tidal zone identification, evaluation framework of overload fences, and DBS dynamic guidance. For DBS tidal zone identification, tidal zone identification and location from each fence with bicycle flows are provided with the HDBSCAN clustering method. The evaluation framework, covering DBS flows and the parking demand density, is proposed to assess the characteristics of overload fences. Finally, a DBS dynamic guidance method is provided to balance DBS for the tidal phenomenon with guiding users to the optimal target fence. Extensive experiments conducted on real-world DBS datasets show the effectiveness and accuracy of rebalancing the tidal phenomenon in the DBS system.

Application of BP Neural Networks in Tide Forecasting

Tidal phenomenon is a significant dynamical phenomenon in the ocean, and the accurate prediction of tide is an important task for various maritime activities. This paper proposes analysis method considering tidal periodicity and apply it to the actual tide prediction. The results prove that this method can solve the delay problem in tide prediction, improve the accuracy of prediction. Compared with the tidal harmonic analysis method, the prediction result of this method is more accurate and requires less data for short-term tidal forecast. Although this study can only provide an accurate forecast for 3 days, it is enough to deal with risks. How to improve the accuracy of long-term prediction is one of the future research directions.