Pemodelan Kecepatan Arus dan Tinggi Gelombang  Pada Rencana Breakwater Kolam Pelabuhan Meulaboh   Dengan Menggunakan Program Delft3D

The Meulaboh port in West Aceh Regency is one of the ports in the west coast of Aceh Province. Initial operation of this port began in 2016 and currently serves crossing activities with the Meulaboh - Sinabang pass. The Meulaboh port is located in open water facing the Indian Ocean. In extreme conditions, ships often have to delay shipping due to high waves that cause shocks to the ship. Based on these problems, the study will provide an overview of the impact and hydrodynamic response of the Meulaboh port pool area and analyze the impact of wave heights on activities in the port pond based on several Breakwater construction layout scenarios. Alternative handling scenarios are carried out using the Delft3D program. The distribution of wave height at the direction of the wind from the Southwest with Hs = 4.908 m, and Ts = 7.254 seconds which shows the dominant wave from the Southwest restrained by Breakwater and the wave height in front of the port mouth ranges from between 0-1 meters so it is safe against activities cruise.

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The Characteristics of West Season Wind and Wave as well as Their Impacts on Ferry Cruise in The Kalianget-Kangean Cruise Route, Madura, Indonesia

Pertanika Journal of Science and Technology ◽

10.47836/pjst.29.3.16 ◽

2021 ◽

Vol 29 (3) ◽

Author(s):

Viv Djanat Prasita ◽

Lukman Aulia Zati ◽

Supriyatno Widagdo

Keyword(s):

Wind Speed ◽

Wave Height ◽

The West ◽

Wind Speeds ◽

Wave Patterns ◽

Time Stamps ◽

The Mean ◽

Two Peaks ◽

The Impact ◽

Descriptive Statistical Analysis

The wind and wave conditions in the waters of the Kalianget-Kangean cruise route in the west season are relatively high so that these winds and waves can have a dangerous impact on that cruise route. The aim of this research was to analyze the characteristics of wind speed and wave height over a 10 year period (2008-2017), as well as to evaluate the weekly patterns for three months (December 2017-February 2018). These time stamps represent the west season in waters at Kalianget-Kangean route, and to identify the impact of winds and wave on this path. The method used in this research is descriptive statistical analysis to obtain the mean and maximum values of wind speed and wave height. Wind and wave patterns were analyzed by WRPlot and continued with mapping of wind and wave patterns in the waters of Kalianget-Kangean and its surroundings. The data used was obtained from the Meteorology, Climatology and Geophysics Agency. The results show wind and wave characteristics with two peaks formed regularly between 2008-2017, marking the west and east monsoons. In addition, the wind speed and wave height were generally below the danger threshold, ie <10 knots and <2 m, respectively. However, there are exceptions in the west season, especially at the peak in January, where the forces are strengthened with a steady blowing direction. The maximum wind speed reaches and wave height reaches 29 knots and 6.7 m, respectively. The weekly conditions for both parameters from December 2017 to February 2018 were relatively safe, for sailing. Moreover, January 23-29, 2018 featured extreme conditions estimated as dangerous for cruise due to the respective maximum values of 25 knots and 3.8 m recorded. The channel is comparably safe, except during the western season time in December, January, February, characterized by wind speeds and wave height exceeding 21 knots and 2.5 m, correspondingly.

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Growth of Wave Height with Retreating Ice Cover in the Arctic

10.5194/egusphere-egu2020-6557 ◽

2020 ◽

Author(s):

Changlong Guan ◽

Jingkai Li

Keyword(s):

Arctic Ocean ◽

Surface Waves ◽

Wave Height ◽

Open Water ◽

Ice Cover ◽

Wave Climate ◽

Least Square ◽

The Arctic ◽

The Arctic Ocean ◽

Wave Heights

For the Arctic surface waves, one of the most uncontroversial viewpoints is that their escalation in the past few years is mainly caused by the ice extent reduction. Ice retreat enlarges the open water area, i.e., the effective fetch, and thus allows more wind input energy and available distance for wave evolution. This knowledge has been supported by a few previous studies on the Arctic waves which analyzed the correlation between time-series variations in wave height and ice coverage. However, from the perspective of space, the detailed relationship between retreating ice cover and increasing surface waves is not well studied. Hence, we performed such a study for the whole Arctic and its subregions, which will be helpful for a better understanding of the wave climate and for forecasting waves in the Arctic Ocean.Wave data are produced by twelve-year (2007-2018) hindcasts of summer melt seasons (May-Sept.) and numerical tests with WAVEWATCH III. When a viscoelastic wave-ice model and a spherical multiple-cell grid are applied, simulated wave heights agree with available buoy data and previous research. After the validations, simulated significant wave heights over twelve-year summer melt seasons are used to demonstrate the detailed relationship between the escalation of wave height and reduction of ice extent for the whole Arctic and seven subregions. Through least square regression, we find that the mean wave height in the Arctic Ocean will increase by 0.071m (106km2)-1 when the ice extent is smaller than 9.4&#215;106km2, and roughly 51% is contributed by the enlarged fetch. By analyzing the nondimensional wave energy and comparing the simulated wave height with Wilson IV, we prove the swell is widespread during the summertime in the current Arctic Ocean. Furthermore, we also display the variations in probabilities of occurrence of large waves as ice-edge retreats in seven subregions. Assuming that an ice free period occurs in the Arctic in September, the model results show that the simulated mean wave height is approximately 1.6m and the large waves occur much more frequently, which mean that the growth rate of wave height will be higher if the minimum ice extent keeps reducing in the future.

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Ocean State Forecast along Ship Routes: Evaluation Using ESSO-INCOIS Real-Time Ship-Mounted Wave Height Meter and Satellite Observations

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-15-0047.1 ◽

2015 ◽

Vol 32 (11) ◽

pp. 2211-2222 ◽

Cited By ~ 1

Author(s):

R. Harikumar ◽

N. K. Hithin ◽

T. M. Balakrishnan Nair ◽

P. Sirisha ◽

B. Krishna Prasad ◽

...

Keyword(s):

Indian Ocean ◽

Correlation Coefficient ◽

Wave Height ◽

Significant Wave Height ◽

Satellite Observations ◽

Southern Indian Ocean ◽

Significant Wave ◽

Safe Navigation ◽

Wave Heights ◽

The Indian Ocean

AbstractOcean state forecast (OSF) along ship routes (OAS) is an advisory service of the Indian National Centre for Ocean Information Services (INCOIS) of the Earth System Science Organization (ESSO) that helps mariners to ensure safe navigation in the Indian Ocean in all seasons as well as in extreme conditions. As there are many users who solely depend on this service for their decision making, it is very important to ensure the reliability and accuracy of the service using the available in situ and satellite observations. This study evaluates the significant wave height (Hs) along the ship track in the Indian Ocean using the ship-mounted wave height meter (SWHM) on board the Oceanographic Research Vessel Sagar Nidhi, and the Cryosat-2 and Jason altimeters. Reliability of the SWHM is confirmed by comparing with collocated buoy and altimeter observations. The comparison along the ship routes using the SWHM shows very good agreement (correlation coefficient > 0.80) in all three oceanic regimes, [the tropical northern Indian Ocean (TNIO), the tropical southern Indian Ocean (TSIO), and extratropical southern Indian Ocean (ETSI)] with respect to the forecasts with a lead time of 48 h. However, the analysis shows ~10% overestimation of forecasted significant wave height in the low wave heights, especially in the TNIO. The forecast is found very reliable and accurate for the three regions during June–September with a higher correlation coefficient (average = 0.88) and a lower scatter index (average = 15%). During other months, overestimation (bias) of lower Hs is visible in the TNIO.

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Does Wave Height Matter for Effective Surface Dispersant Application?

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-2014.1.747 ◽

2014 ◽

Vol 2014 (1) ◽

pp. 747-761

Author(s):

Charles Huber ◽

Alexis Steen ◽

Brian Parscal

Keyword(s):

Crude Oil ◽

Wave Height ◽

Breaking Waves ◽

Time Of Application ◽

Tier Ii ◽

Increased Risk ◽

Wave Heights ◽

Wave Conditions ◽

In The Beginning ◽

The Impact

ABSTRACT The Deepwater Horizon (DWH) crude oil release provided an occasion to test the delivery and effectiveness of dispersants on surface oil slicks to reduce the potential exposure of shoreline habitats and marine wildlife to spilled oil. In the beginning of the DWH response, there was concern that the calm sea conditions did not provide sufficient wave energy for dispersant action to occur. At one point a minimum 3-foot wave height requirement for dispersant application was set in an attempt to ensure sufficient mixing energy for dispersant activation was present at the time of application. Because of the ability of aerial dispersant application to rapidly treat large spatial areas and quantities of oil, there was a contrasting concern that a 3-foot (0.91 m) minimum wave height requirement was overly restricting dispersant operations; thereby, increasing environmental exposures. To evaluate the wave heights that effectively dispersed the Macondo crude oil, the SMART (Special Monitoring of Applied Response Technologies) Tier II/III monitoring data of dispersant applications performed in low wave conditions, i.e., < 3 ft (0.91m) were analyzed. Of the 27 SMART Tier II/III monitoring operations conducted in significant wave heights (SWHs) of < 3 feet (0.91 m), 21 were reported as “effective,” 4 were reported as “inconclusive,” and only 2 were reported as “no observed dispersion.” These results demonstrate dispersants were effective in low wave conditions and on weathered Macondo crude oil as a function of distance from the spill site. The paper then estimates the impact that setting wave height restrictions has on dispersant operations showing that a > 3 feet requirement could reduce surface dispersant operational days by as much as 67%. With the dispersant assets available during the DWH response, this could have resulted in leaving up to 700,000 gallons of oil per day on the water,a thus exposing shoreline habitat and offshore wildlife to an increased risk of oiling. The paper concludes thatWave height should not be used as a criterion for approving or conducting surface dispersant application operations, becausewave heights as low as 0.5–1.0 feet were effective in immediately dispersing fresh and weathered Macondo crude oil, and may be sufficient to disperse other oils, andResearch on dispersant application in calm sea conditions has shown that oils would rapidly and almost totally disperse when exposed to breaking waves after being left on a calm water surface for prolonged periods. The paper recommends that government and response organizations should review and consider revising their guidance and operational procedures for dispersant application approval in light of the analysis presented in this paper.

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Computing Domestic Prices in Precolonial West Africa: A Methodological Exercise from the Slave Coast

History in Africa ◽

10.2307/3172064 ◽

1991 ◽

Vol 18 ◽

pp. 239-257 ◽

Cited By ~ 5

Author(s):

Robin Law

Keyword(s):

West African ◽

Methodological Issues ◽

The West ◽

African Slave ◽

Domestic Prices ◽

European Trade ◽

The Indian Ocean ◽

Republic Of Benin ◽

The Impact ◽

Local Value

The present paper is a by-product of a recently completed study of the impact of the Atlantic slave trade in the West African ‘Slave Coast’ (roughly, the modern Republic of Bénin). One of the most striking features of the operation of the European trade in this region was the prominence among the commodities imported of cowry shells (brought ultimately from the Maldive Islands in the Indian Ocean), which were used locally as a currency. Assessment of the impact of the European trade obviously requires detailed empirical study of the operation of this cowry currency, and in particular of the question of whether the massive importation of cowries which it involved led to significant depreciation of their local value. A more extended treatment of this subject is in preparation. Although there is a great deal of contemporary documentation of the prices of various commodities in local markets between the seventeenth and nineteenth centuries, this evidence presents considerable problems of interpretation and evaluation. This paper deals with these methodological issues, in the belief that they may be potentially illuminating for the study of other areas than the Slave Coast.

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Weather Window Analysis of Irish and Portuguese Wave Data With Relevance to Operations and Maintenance of Marine Renewables

Volume 8: Ocean Renewable Energy ◽

10.1115/omae2013-11125 ◽

2013 ◽

Cited By ~ 2

Author(s):

Michael O’Connor ◽

Tony Lewis ◽

Gordon Dalton

Keyword(s):

Wave Height ◽

Wave Energy ◽

West Coast ◽

Atlantic Coast ◽

The West ◽

Wave Data ◽

Window Analysis ◽

Operations And Maintenance ◽

Wave Heights ◽

Waiting Periods

This paper presents the results of a weather window analysis of wave data from the west coast of Ireland and the Atlantic coast of Portugal in order to quantify the levels of access to ocean energy renewables, which may be deployed there, for operation and maintenance activities. In order to operate and maintain offshore marine renewables, a device will have to be accessible for a certain period of time. This will require a weather window consisting of a consecutive period of wave heights low enough and long enough for the device to be accessed. It is important to quantify what the levels of access are off the Irish west coast and Portuguese Atlantic coast given their high wind and wave resource. Wave data from two wave buoys, the M3 buoy located 56km off the west coast of Ireland and the Leixoes buoy located 19km off the Portuguese coast, are analysed to quantify the levels of access that exist. The data is used to quantify the general regimes at both sites by presenting the wave energy resource, the mean annual exceedance and the wave height frequency at both sites. The levels of access are quantified at operations and maintenance (O/M) access limits of Hs 1.0, 1.5, 2.0 and 2.5m wave height, by presenting the number of windows and the percentage of the year that these windows make up as well as the total number of hours, monthly and annual, that the wave heights are below these limits. Also presented are the waiting periods between windows by showing both the longest individual waiting periods between windows in a year and also the total intervals between windows in a year. The levels of access observed off Ireland and Portugal are then compared to levels of access observed at other marine renewable locations, namely the North Sea, Irish East Coast and Pacific North-western US coast. The results indicate that the levels of access off Ireland and Portugal are far below those observed at other marine renewable locations, and at the lower wave height access limits, there are very few suitable weather windows and considerable winter waiting periods between these windows. The implications of these low levels of access suggest that maintaining wave energy converters, off the west coast, may not be feasible and devices will need to be brought ashore for O/M activities.

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The Indian Ocean Tsunami: Economic Impact, Disaster Management, and Lessons

Asian Economic Papers ◽

10.1162/asep.2005.4.1.1 ◽

2005 ◽

Vol 4 (1) ◽

pp. 1-39 ◽

Cited By ~ 46

Author(s):

Prema-chandra Athukorala ◽

Budy P. Resosudarmo

Keyword(s):

Indian Ocean ◽

Economic Impact ◽

Disaster Management ◽

National Development ◽

Indian Ocean Tsunami ◽

Aceh Province ◽

The Indian Ocean ◽

Policies And Programs ◽

Andaman Earthquake ◽

The Impact

This paper documents and analyzes the immediate economic impact of the Indian Ocean tsunami generated by the Sumatra-Andaman earthquake of 26 December 2004, with a focus on Indonesia (Aceh province) and Sri Lanka, and assesses the disaster management process. The preliminary findings point to the importance of educating the public about simple precautions in the event of a disaster and enforcing coastal environmental regulations. The findings also argue for designing policies and programs, as an integral part of national development strategies, for mitigating the impact of natural disasters on the poor and highlight the need for combining international aid commitments with solutions to the limited aid-absorptive capacity in disaster-affected countries.

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The Impact of Tropical Cyclone Seroja to The Rainfall and Sea Wave Height in East Nusa Tenggara

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/925/1/012049 ◽

2021 ◽

Vol 925 (1) ◽

pp. 012049

Author(s):

R Kurniawan ◽

H Harsa ◽

M H Nurrahmat ◽

A Sasmito ◽

N Florida ◽

...

Keyword(s):

Tropical Cyclone ◽

Wave Height ◽

Extreme Rainfall ◽

Active Phase ◽

Extreme Rainfall Events ◽

Rainfall Events ◽

The Indian Ocean ◽

The Impact ◽

The City ◽

Sea Wave

Abstract Natural events following the activity of the Tropical Cyclone Seroja in April 2021 are investigated. During its active phase, Tropical Cyclone Seroja generated extreme rainfall events in some sub-provinces of East Nusa Tenggara (NTT): Ngada, Alor, Belu, Rote Ndao on 4 April, 2021, Kupang on 4 to 5 April, 2021, East Sumba on 4 to 6 April, 2021. Moreover, these extreme rainfall events triggered flood in Alor, East Flores, Lembata, The City of Kupang, Kupang, East Sumba, Malaka, Belu, and North Central Timor. The maximum sea wave height of the Indian Ocean at the Southern part of NTT was also increasing, from 4 meters on 1 to 2 April, 2021 up to 6 meters on 3 April, 2021, and rose to higher than 7 meters on 4 to 6 April, 2021. On 7 to 9 April, 2021, the sea wave height declined as the Tropical Cyclone Seroja moved to the Southwest of NTT.

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Contemporary Qur'anic Studies in Iran and its Relationship with Qur'anic Studies in the West

Journal of Qur anic Studies ◽

10.3366/jqs.2012.0037 ◽

2012 ◽

Vol 14 (1) ◽

pp. 45-72

Author(s):

Morteza Karimi-Nia

Keyword(s):

Islamic Law ◽

Human Sciences ◽

The West ◽

Communications Technologies ◽

Religious Learning ◽

The Status ◽

Islamic Republic Of Iran ◽

Almost All ◽

The Impact ◽

The Relationship

The status of tafsīr and Qur'anic studies in the Islamic Republic of Iran has changed significantly during recent decades. The essay provides an overview of the state of Qur'anic studies in Iran today, aiming to examine the extent of the impact of studies by Western scholars on Iranian academic circles during the last three decades and the relationship between them. As in most Islamic countries, the major bulk of academic activity in Iran in this field used to be undertaken by the traditional ʿulamāʾ; however, since the beginning of the twentieth century and the establishment of universities and other academic institutions in the Islamic world, there has been increasing diversity and development. After the Islamic Revolution, many gradual changes in the structure and approach of centres of religious learning and universities have occurred. Contemporary advancements in modern sciences and communications technologies have gradually brought the institutions engaged in the study of human sciences to confront the new context. As a result, the traditional Shīʿī centres of learning, which until 50 years ago devoted themselves exclusively to the study of Islamic law and jurisprudence, today pay attention to the teaching of foreign languages, Qur'anic sciences and exegesis, including Western studies about the Qur'an, to a certain extent, and recognise the importance of almost all of the human sciences of the West.

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Faiza Ambah's Mariam and the Embodied Politics of Veiling in France

Paragraph ◽

10.3366/para.2019.0310 ◽

2019 ◽

Vol 42 (3) ◽

pp. 333-350

Author(s):

Kaya Davies Hayon

Keyword(s):

The West ◽

Everyday Lives ◽

Embodied Experiences ◽

Primary Means ◽

The Veil ◽

Islam And Secularism ◽

The Impact

This article argues that Mariam uses its eponymous heroine's lived and embodied experiences of veiling to explore the impact of French secular legislation on Muslim schoolgirls' everyday lives in France. Interweaving secularism studies, feminism and phenomenology, I argue that the film portrays the headscarf as the primary means by which its protagonist is able to resist male patriarchal authority and negotiate her hybrid subjectivity. I conclude that Mariam offers a nuanced representation of veiling that troubles the perceived distinctions between Islam and secularism, oppression and freedom, and the veil and feminism in France and the West.

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