Flood Tide Research Articles

PENANGANAN BANJIR DAERAH ALIRAN SUNGAI BABON KOTA SEMARANG

Floods are natural disasters that we often encounter during the rainy season. Apart from there are also tidal floods which are caused by global warming, this problem occurs in the city of Semarang, especially North Semarang, specifically the north coast of the Java Sea. Floods that occurred in 2021 in the city of Semarang include Starting from Genuk, Kaligawe, Satsiun Tawang, Tanjungmas, Karangayu, the flood disaster was caused by high rainfall, while tidal floods caused high tides and inundated roads and houses of residents on the north coast of Semarang city. To handle this problem, the government Currently we have made embankments, namely making embankments including the Sringin River which is equipped with a ponpa, Tenggang River, Babon River, Semarang River, Banger River, and others. These embankments are equipped with pumps so that when the water from upstream to downstream is high, the water is pumped. to the sea, the aim is to find out one of the annual discharges of the river, namely the Babon, and to find out the tamping capacity of the Babon River Longstorage. Apart from that, there is a method for handling tidal floods, namely using the Babon River Longstorage which is equipped with a pump, if there is high tide which inundates roads and houses. residents then the pump is turned on, whereas if the water recedes and does not inundate residential areas then the pump is turned off. Flood control analysis is calculated using the HEC-RAS program simulation using a return period of 50 years. Based on calculations using the HEC-HMS program. The flood discharge is 2,529 m3/sec. The high tide elevation is + 1.67 m, while the normal water level is -0.5 m.

Application of sma method and ahp to predict the level of tidal flood vulnerability in Tegal City

Application of sma method and ahp to predict the level of tidal flood vulnerability in Tegal City

Sea Level Tidal Attributes in Port Said Harbor, Eastern Egyptian Mediterranean Coast

Observed sea level data attained from a pressure sensor tide gauge, installed inside Port Said harbor in Egypt, was utilized to modernize tidal characteristics and surges in the study area. Five years of hourly sea level dataset (June 2010 to June 2015) were analyzed using the harmonic analysis approach of Delft-3D Tide suit. The results of the analysis revealed that the semi-diurnal constituents (M2, S2), together with the solar annual (Sa) dominate tide behavior in the area. Furthermore, a semidiurnal tidal regime by a ratio of 0.21 is based on the form factor (FF) equation. Moreover, tidal asymmetry (Ar.) shows a flood tide with a short period of a value equal to 0.01068 > 0.01, which reflects a tide wave distortion. From power spectral analysis, the sea-level change is controlled by both the significant tidal and non-tidal (storm surge) components by almost an equal percentage of 50.63 % and 49.37 % respectively. Additionally, the residual from sea level harmonic analysis was annually correlated with the meteorological parameters of wind, temperature, and atmospheric pressure to estimate their effect on Sea-Level Rise (SLR). A small positive trend line of SL was distinguished in the years from 2011 to 2015 by approximately (2 mm/yr.) due to the weak correlation of meteorological parameters, in conjunction with a conventional relationship with atmospheric pressure and temperature. In 2010, a slight negative linear tendency was noticed of 0.3 mm/yr., which can be related to the direct proportional relation of atmospheric pressure and surge component, besides an inversely proportional relation of air temperature and residual component, regardless of the weak correlation with wind vector. Overall, the research provides insights into the tidal characteristics, surges, and sea-level rise in Port Said Harbor. Understanding these attributes serves the objective of this paper to assess the impact of sea-level rise and develop appropriate adaptation strategies in coastal areas

Racial hydrologies

AbstractIn the South Carolina Lowcountry, near‐annual hurricanes and record‐breaking sea levels have led to disastrous flooding, overwhelming the region's historical tidal infrastructures and entrenched racial geographies. In response, Lowcountry governments, institutions, and residents have undertaken efforts at “perimeter protection,” raising dikes and seawalls to safeguard selected urban and rural plantation spaces from tidal flooding. Although perimeter protection is presented as a neutral resilience strategy, its practices and material forms reveal a close relationship between coastal protection and efforts to preserve landscapes of white supremacy. Such logics of perimeter protection contrast with everyday affective encounters with eroding coastlines and with the futures outside of bounded edges imagined by Black Charlestonians. By situating the region's hydrological history within the legacy of slavery and plantation extraction, and by following the effects of current sea level rise, we can see how historical hydrologies—which in this case are also racial hydrologies—are entangled with landscapes of contemporary environmental injustice.

On the contribution of tidal floods on damp walls of Venice

The city of Venice, Italy, has historically coped with tidal flooding and is an example of a resilient system, but today the disruptive effects of relative sea level rise pose even more complex challenges. Some of the most significant damage to the city's historic architectural assets is related to the effects of salty water on masonry due to rising damp and tidal flooding. This paper evaluates the entity and distribution of rising damp in seven Venetian brick masonries by quantifying moisture content, soluble salt content, and ion distribution. The distribution is compared with previous literature data and related to tidal and meteorological data recorded prior to sampling. The results show that frequent tidal flooding exacerbates rising damp phenomena within building masonry, resulting in higher moisture contents both in height and depth. Possible future scenarios of relative sea level based on models and the effects of countermeasures such as the MOSE dam are discussed about the likely damage to masonry exposed to rising damp and tidal flooding.

Sediment dynamic on the tidal flat sheltered by artificial engineering: A case study on eddies

Tidal flats are important ecological and terrestrial resources. With the increasing development of coastal engineering projects, it is important to understand the dynamic response of tidal flats to human activities. Hence, the time series of wave, current, and suspended sediment during the spring tide from April 30, 2013 to May 1, 2013 were recorded by three tripod observation systems placed on the upper, middle, and lower parts of the tidal flats south of a constructed harbor in Wanggang, Jiangsu, China. The results showed that eddies formed south of the reclamations during flood tides. The directions of local tidal currents changed from their original southwest to the present northwest, and the ebb tides also changed but continued to flow northeast. The sediment transport process was basically consistent with the currents. The total net sediment fluxes during the tidal cycle (mean values of two tides) on the mudflat were two orders of magnitude larger than those on the salt marsh. Most of the sediments on both the mudflat and the salt marsh were transported northward alongshore, and a small portion of the sediments was transported seaward on the mudflat but shoreward on the salt marsh. The portion of the tidal flat with an elevation >1 m was wide in the north but narrow in the south, as determined by analysis of LiDAR elevation data, which coincided with the local sediment dynamics. The sediments were transported northward from southern deep waters during flood tides, which assisted in the expansion of the tidal flats in the north. This phenomenon reflected unique local sediment dynamics that were highly constrained by reclamations and Dafeng Harbor in the north as well as seawalls in the west. The tidal flat influenced by eddies can extend up to approximately 10 km south of the Dafeng Harbor. This case study has significant implications for the protection of tidal flats and the construction of coastal artificial engineering projects.

The hydrodynamics of Lizard Island lagoon, Great Barrier Reef

Hydrodynamic processes are a major driver for marine systems, linking marine organisms with their environment. However, a lack of hydrodynamic data at an ecologically relevant spatial resolution has stymied our understanding of reef function, as exemplified by Lizard Island on the Great Barrier Reef. To address this gap, 23 to 27 Marotte HS current meters were deployed over three periods, collecting 15 months of current velocity data. Combining these data with wind and tide datasets, we provide a preliminary description of the circulation in the Lizard Island lagoon, examining wind and tide influence, and flushing time. During south-easterly trade winds, flood tides flow through the Lagoon Entrance, while wind-induced waves cross the Bird-South crest, driving a north-westerly flow through Loomis Channel and across the western lagoon. Ebb tides flow east–south-east through the Lagoon Entrance and south-west through the Palfrey-South channel. Tides contribute a mean of 20.4% to the overall current speed, particularly in deeper sites with less reef interference, while shallow sites were more influenced by wind. Lizard Island lagoon flushing times ranged from a few hours to 10 days; longer during periods with low wind speeds. Hindcast flushing times during the 2016 coral bleaching event (following 8 Degree Heating Weeks) were approximately 22 h, suggesting that flushing time likely had minimal influence on bleaching. Our analyses provide initial insights into the circulation of the Lizard Island system and aid understanding of the potential relationships between reef organisms and their physical environment, bridging the gap between ecology and hydrodynamics.

Enhancing regional resilience: assessing tidal flood vulnerability and adaptation strategies in a coastal community

Abstract This study aims to assess the vulnerability of communities in Sungai Pauh, Sungai Pauh Pusaka, and Sungai Pauh Tanjung, Langsa, Aceh Province to tidal flooding, and understand their adaptation strategies and the main socio-economic and environmental contributors to vulnerability. A mixed methods approach combines quantitative vulnerability index calculations with qualitative data from interviews. We assessed the vulnerability index using secondary data sources (population density, gender, vulnerable age, poor population, and disabled population) to evaluate the vulnerability of communities. The 34 key informants represent various levels of society, including village officials, government employees, and the community. High social vulnerability was identified, related to population density, gender, age, poverty, and disability, while economic vulnerability was low due to dependence on fishing. The recommendations include knowledge dissemination, public awareness campaigns, the formation of community groups for flood relief, and infrastructure development, with a focus on channel reconstruction to increase resilience and reduce the impact of tidal floods.

Characteristics of internal waves in the Bali Sea from Sentinel-1A data and ocean modeling

Abstract Internal waves (IWs) that propagate into the Bali Sea are supposed to originate from the generating sill area in the southern part of the Lombok Strait. This study aims to investigate surface features and mechanism of IWs formation and propagation into the Bali Sea. The datasets are acquired from the Sentinel-1A imageries and CROCO model simulation. The results showed that solitary wave packets are spread over two areas: near Lombok Strait as generating area, and in the western and northern parts of the Bali Sea as propagating area. The length of IWs crests increased as they moved into the propagation area. The model showed that mixed semidiurnal tidal currents near the sill flow northward (southward) alternately during the flood (ebb) tidal period, resulting in the pycnocline deepening down to ~400 m near the northern sill area during the flood tide. Furthermore, the model demonstrated an alternating upward and downward movement of vertical currents components, associated with propagation of IWs’ crests and troughs along IWs pathway.

Instrumentation for Monitoring and Early Warning of Tidal Flood Using ESP32S2 Microcontroller and A01NYUB Ultrasonic Sensor in Tambakrejo, Semarang

Abstract A tidal flood early warning system is crucial to minimize the impact and loss in tidal flood-prone areas. This research proposes an instrumentation and information system for tidal flood early warning monitoring by optimizing tidal data in the local area. The efficiency of the instrumentation depends on the accuracy of the sensors installed. This research presents the testing and application of The A01NYUB ultrasonic sensor with The ESP32S2 microcontroller for real-time technology-based water level monitoring and The Internet of Things concept. The collected sensor data is analyzed with an algorithm that has also been proposed in this research. The results show that the ultrasonic sensors can provide a reliable and adequate tide monitoring scheme with an accuracy of RMSE value of 0.08943 and bias value of – 2×10−16. The developed system provides early warning when the sea level reaches 260-280 cm with the MSL datum reference value range of -20 cm to 40 cm. The system has been tested at the Fisherman Boat Harbor, Tambakrejo, Semarang, Central Java, Indonesia. The test has shown the system’s accuracy and has proven that the developed system will help minimize the impact of the tidal flood disaster.

The effect of water tidal flood towards the durability of asphalt concrete wearing course (ac-wc) mixture

The effect of water tidal flood towards the durability of asphalt concrete wearing course (ac-wc) mixture

The Community Adaptation Strategies to Tidal Floods (Case Study: Karangjompo Community, Tirto Sub-District, Pekalongan Regency)

The Community Adaptation Strategies to Tidal Floods (Case Study: Karangjompo Community, Tirto Sub-District, Pekalongan Regency)

Monitoring post-spawning movement, habitat use, and survival of adult anadromous rainbow smelt using acoustic telemetry in a New Hampshire estuary.

Anadromous rainbow smelt (Osmerus mordax, [Mitchill 1814]) are found along the northeast Atlantic coastline of North America, with their range now limited to north of Cape Cod, Massachusetts, USA. Although their anadromous life cycles are described broadly, gaps remain regarding how adult rainbow smelt use estuaries post-spawning, including movement behaviors, habitats used, and specific timing of emigration to coastal waters. In spring 2021, we used acoustic telemetry to characterize movements during and after the spawning season of rainbow smelt captured in tributaries to Great Bay, New Hampshire, USA, a large estuarine system near the southern edge of their range. Forty-four adult rainbow smelt (n = 35 male, n = 9 female) were tagged with Innovasea V5 180-kHz transmitters and an array of 22,180 kHz VR2W receivers were deployed throughout Great Bay to detect movements of tagged fish from March to October 2021. Rainbow smelt were detected 14,186 times on acoustic telemetry receivers, with 41 (93%) of the tagged individuals being detected at least once post-tagging. Individuals were detected moving between tributaries, revealing that rainbow smelt can use multiple rivers during the spawning season (March-April). Mark-recapture Cormack-Jolly-Seber models estimated 83% (95% confidence interval 66%-92%) of rainbow smelt survived to the mainstem Piscataqua River, and a minimum of 50% (22 of 44) reached the seaward-most receivers and were presumed to have survived emigration. Most individuals that survived remained in the estuary for multiple weeks (average = 19.47 ± 1.99 standard error days), displaying extended use of estuarine environments. Downstream movements occurred more frequently during ebb tides and upstream movements with flood tides, possibly a mechanism to reduce energy expenditures. Fish emigrated from the estuary by mid-May to the coastal Gulf of Maine. Our results underscore that rainbow smelt need access to a variety of habitats, including multiple tributaries and high-quality estuarine habitat, to complete their life cycle.

Establishing flood thresholds for sea level rise impact communication.

Sea level rise (SLR) affects coastal flood regimes and poses serious challenges to flood risk management, particularly on ungauged coasts. To address the challenge of monitoring SLR at local scales, we propose a high tide flood (HTF) thresholding system that leverages machine learning (ML) techniques to estimate SLR and HTF thresholds at a relatively fine spatial resolution (10 km) along the United States' coastlines. The proposed system, complementing conventional linear- and point-based estimations of HTF thresholds and SLR rates, can estimate these values at ungauged stretches of the coast. Trained and validated against National Oceanic and Atmospheric Administration (NOAA) gauge data, our system demonstrates promising skills with an average Kling-Gupta Efficiency (KGE) of 0.77. The results can raise community awareness about SLR impacts by documenting the chronic signal of HTF and providing useful information for adaptation planning. The findings encourage further application of ML in achieving spatially distributed thresholds.

Capturing the net ecosystem CO2 exchange dynamics of tidal wetlands with high spatiotemporal resolution by integrating process-based and machine learning estimations

Accurate estimation of the net ecosystem CO2 exchange (NEE) at regional scales is of great significance for studying the carbon sink potential of coastal wetland ecosystems and their responses to global climate change. However, current NEE estimation methods are mainly developed for terrestrial ecosystems and are therefore unsuitable for NEE estimation with high spatiotemporal resolution estimation in coastal wetlands subjected to sub-daily tidal flooding. In this study, we proposed a high spatiotemporal resolution NEE estimation method for coastal marsh wetlands that properly considered tidal influence by combining the advantages of process-based modeling and machine learning. This method was verified and applied in the Changjiang estuary and Liaohe estuary marsh wetlands based on eddy covariance and environmental measurements, climate reanalysis data, and satellite images. The proposed method had good performance in the NEE estimation of tidal marsh wetlands, with Phragmites australis, Spartina alterniflora, and Suaeda salsa having coefficients of determination (R2) of 0.850, 0.676, and 0.658, respectively, and root mean square error (RMSE) values of 7.211 μmol m−2 s−1, 8.105 μmol m−2 s−1, and 0.109 μmol m−2 s−1, respectively. By integrating the tide level and salinity, the NEE estimation accuracy for each vegetation type was improved. The total annual NEE values of the Changjiang estuary and Liaohe estuary marsh wetlands in 2022 were estimated to be −0.297 and −0.444 Tg C yr−1, respectively. This study demonstrated that integrating process-based model and machine learning estimation can reliably capture the NEE dynamics of coastal wetlands, providing a useful tool to quantify coastal blue carbon potential with high spatiotemporal resolution at large scales.

Coastal Tidal Flat And Tidal Current Observation Based On Satellite Remote Sensing

Satellite remote sensing has been an effective way to acquire surface image sequences of costal field, and the satellite video at a frame rate of multiple frames per second could provide chance for short-time observations at high temporal resolution such as the observation of surface tidal currents. The observation of surface tidal currents has been facilitated by advanced image preprocessing methods and large-scale image velocimetry, while the space-time volume velocimetry (STVV) was used in this study. STVV can simultaneously obtain the direction and magnitude of the flow velocity through the surface texture without any artificial tracers, hence it is considered as a promising method. Since it has only been proposed in recent years, this study evaluated the accuracy of the STVV algorithm and tested the robustness of the STVV to environmental disturbance factors firstly. The simulated image sequences were used so that the exact accuracy of STVV can be known by comparing the measured and ground truth values since the ground truth of the pixel flow velocity is predictable and modifiable. The effects of the two main STVV parameters, the size of the search area and the selected frames of images, on the results were analyzed, and the robustness against image noise and fog was examined. The size of the search area and selected frames of images were found having the similar effects on the calculation results that the larger both are, the higher the calculation accuracy will be. Although the lower Signal-to-noise ratios lead to more inaccurate results, STVV is robust to image noises from the results in the given cases. Additionally, the accuracy of STVV is acceptable for a small amount of mist, but thicker fog results in large errors. Further research to develop image processing methods to improve the accuracy of STVV in the future is highly necessary. Therefore, based on one satellite video with the frame rate of 10fps and the resolution of 0.95m shooting on September 15th, 2017, surface tidal current observation of the New York Harbor during the flood tide using STVV was achieved. The flow velocity magnitude can reach 3m/s, and the flow direction is consistent with the actual situation. The feasibility of surface tidal current observation using STVV from the satellite video was proved

Management strategies for reducing phosphorus levels in saltwater-intruded agricultural fields

As sea levels continue to rise and high tide flooding events increase in frequency, researchers and farmers alike are looking for solutions to adapt to and mitigate the effects of saltwater intrusion (SWI). Some landowners on the Lower Eastern Shore of Maryland respond to SWI by taking land out of agriculture. For example, they (1) attempt to remediate salt-damaged soils (e.g., planting switchgrass, Panicum virgatum), (2) restore native marsh grasses (e.g., planting saltmarsh hay, Spartina patens), or (3) abandon fields altogether (e.g., allow for natural recruitment). This work examines the ability of each of these land management practices to reduce phosphorus (P) levels in soils and porewater, with the overall goal to benefit both the farming community and water quality in the Chesapeake Bay. We show that remediation and restoration practices are efficient at taking up soil P and reducing porewater P concentrations through biomass P uptake. After three years of growth, we observed an increase in P uptake in biomass of Panicum virgatum (remediation species; 11–30 kg ha−1) and Spartina patens (restoration species; 4–18 kg ha−1) and a decline in available soil P pools (M3P; 30–50 % kg M3P ha−1). At all farms, under all three management strategies, the P fertility index value (FIV) in the topsoil was 33–50 % lower than baseline conditions, likely reducing the potential release of P to nearby waterways. Results from this work will help inform state-level coastal management policies and determine optimal strategies for climate resilience.

Dynamics of microplastic abundance under tidal fluctuation in Musi estuary, Indonesia

Tidal dynamics contribute to fluctuations in microplastic abundance (MPs). This is the first study to characterize MPs under the influence of tidal fluctuations in the Musi River Estuary. MPs samples were collected during flood and ebb tides at 10 research stations representing the inner, middle and outer parts of the Musi River Estuary. MPs were extracted to identify the shape, color and size. MP abundances were 467.67 ± 127.84 particles/m3 during flood tide and 723.67 ± 112.05 particles/m3 during ebb tide. The concentration of MPs in the outer zone of the estuary (ocean) was detected to be higher than in the inner zone of the estuary (river). The MPs found were dominated by black color, film shape and size 101–250 μm. A greater abundance of MPs at ebb tide than at flood tide implies that the Musi Estuary's largest source of emissions is discharge from the river.

Adaptive Capacity of Fishermen in Facing Tidal Floods with Vulnerability to Viability (V2V) Approach

Tambakrejo’s small-scale fishing households have low socio-economic capabilities and must face the problem of tidal flooding. Therefore, this research has the following objectives: 1) To identify the vulnerability of fishing households in Tambakrejo Fishermen Village to social-ecological changes due to tidal flooding. 2) To investigate the adaptive responses of fishermen households in facing socio-ecological changes due to tidal flooding. This research uses primary data by using semi-structured interviews. The number of respondents in the study was 60, determined by the snowball sampling technique. The data were analyzed using descriptive statistical methods. The results of the research show that the community is vulnerable to both natural and institutional aspects. Adaptive responses shape community resilience through increased collaboration capacity and community learning capacity. This research contributes to the government's ability to distribute assistance to the community, especially fishing households affected by tidal flooding.

Pemetaan Daerah Banjir Rob Akibat Kenaikan Muka Air Laut di Wilayah Kecamatan Sasak Ranah Pasisie Kabupaten Pasaman Barat

Tidal flooding often occurs in coastal areas and this is sometimes very difficult to predict because it can occur suddenly this happens because sea water is higher than the land surface. This research aims at 1) vulnerability to tidal flooding due to sea level rise,, 2) disaster mitigation of community preparedness. This type of research is quantitative. Data were analyzed using the overlay method and mitigation using the PLS (Partial Least Square) approach, and by taking random sampling of the population. This research results in 1) tides have a formzahl value of 0.31 with a mixed type leaning to double daily occurring twice the tide and twice the ebb with almost the same height, in tidal affected areas have 2 classes, namely vulnerable and not vulnerable areas that are quite vulnerable have an area of 1009 Ha. The distribution of areas classified as quite vulnerable is in areas close to the coast. Areas that are not vulnerable have an area of 11,173 with areas that are not close to the coast. 2) on policies, emergency response plans, disaster warning systems, resource mobility is able to explain the preparedness variable by 60.9%. Based on the results of these calculations it can be concluded that this research model is included in the moderate or moderate category. Because if > 0.50 indicates a moderate model.