Coastal Dynamics 2017 Paper No. 156 513 How Tides and Waves
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Coastal Processes and Longshore Sediment Transport Along Krui Coast, Pesisir Barat of Lampung
ICOSITER 2018 Proceeding Journal of Science and Applicative Technology Coastal Processes and Longshore Sediment Transport along Krui Coast, Pesisir Barat of Lampung Trika Agnestasia Tarigan 1, Nanda Nurisman 1 1 Ocean Engineering Department, Institut Teknologi Sumatera, Lampung Selatan, Lampung Abstract. Longshore sediment transport is one of the main factors influencing coastal geomorphology along the Krui Coast, Pesisir Barat of Lampung. Longshore sediment transport is closely related to the longshore current that is generated when waves break obliquely to the coast. The growth of waves depends upon wind velocity, the duration of the wind, and the distance over which the wind blow called fetch. The daily data of wind speed and direction are forecast from European Centre for Medium-Range Weather Forecasts (ECMWF). This study examines for predicting longshore sediment transport rate using empirical method. The wave height and period were calculated using Shore Protection Manual (SPM) 1984 method and the longshore sediment transport estimation based on the CERC formula, which also includes the wave period, beach slope, sediment grain size, and breaking waves type. Based on the use CERC formula it is known that from the Southeast direction (Qlst(1) ) the sediment transport discharge is 2.394 m3/s, in 1 (one) year the amount of sediment transport reaches 75,495,718 m3/s. 3 Whereas from the northwest direction of (Qlst(2)) the sediment transport debit is 2.472 m /s, in 1 (one) year the amount of sediment transport reaches 77,951,925 m3/s. 1. Introduction The geographical condition of Krui Coast which is directly adjacent to the Indian Ocean makes this area get a direct influence from the physical parameters of the sea, which is the wave. -
Wintertime Coastal Upwelling in Lake Geneva: an Efficient Transport
RESEARCH ARTICLE Wintertime Coastal Upwelling in Lake Geneva: An 10.1029/2020JC016095 Efficient Transport Process for Deepwater Key Points: • Coastal upwelling during winter in a Renewal in a Large, Deep Lake large deep lake was investigated by Rafael S. Reiss1 , U. Lemmin1, A. A. Cimatoribus1 , and D. A. Barry1 field observations, 3‐D numerical modeling, and particle tracking 1Ecological Engineering Laboratory (ECOL), Faculty of Architecture, Civil and Environmental Engineering (ENAC), • Upwelled water masses originating from the deep hypolimnion spend Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland up to 5 days near the surface before descending back into that layer • Wintertime coastal upwelling is an Abstract Combining field measurements, 3‐D numerical modeling, and Lagrangian particle tracking, fi ef cient yet overlooked process for we investigated wind‐driven, Ekman‐type coastal upwelling during the weakly stratified winter period deepwater renewal in large deep lakes with favorable wind conditions 2017/2018 in Lake Geneva, Western Europe's largest lake (max. depth 309 m). Strong alongshore wind stress, persistent for more than 7 days, led to tilting and surfacing of the thermocline (initial depth Supporting Information: 75–100 m). Observed nearshore temperatures dropped by 1°C and remained low for 10 days, with the lowest • Supporting Information S1 temperatures corresponding to those of hypolimnetic waters originating from 200 m depth. Nearshore • Movie S1 current measurements at 30 m depth revealed dominant alongshore currents in the entire water column − (maximum current speed 25 cm s 1) with episodic upslope transport of cold hypolimnetic waters in the fi ‐ Correspondence to: lowest 10 m mainly during the rst 3 days. -
Evolution of Spectra for Mechanical and Wind Waves in a Large Tank
V. Polnikov, F. Qiao, H. Ma, and S. Jiang EVOLUTION OF SPECTRA FOR MECHANICAL AND WIND WAVES IN A LARGE TANK Vladislav Polnikov1†1, Fangli Qiao2, 3, Hongyu Ma2, and Shumin Jiang2 1A.M. Obukhov Institute of Atmospheric Physics of RAS, Moscow, Russia 2First Institute of Oceanography of MNR, Qingdao, China 3Laboratory for Regional Oceanography and Numerical Modeling, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China (Received xx; revised xx; accepted xx) Empirical spectra for mechanical and wind waves measured in a large tank of the First Institute of Oceanography of China are presented. Analysis for the first and the second type of waves is done separately. It is shown that, in the case of mechanical waves with a steepness more than 0.2, the frequency spectra of waves evolve to ones with the tail decay S() f f 4.2 0.1 , whilst the shape of spectra at large fetches is self-similar. Numerical solutions of the four-wave kinetic equation, written in the fetch-limited version, result in the same spectra. This allows treating the empirical observations for mechanical waves as the natural evolution of free nonlinear surface waves. In the case of wind waves, the wave spectra evolve to ones with the tail decay S() f f 4.0 0.05 at fetches X greater than 8 meters, under any applied winds. The well-known 3/2 Toba’s “three-second relation”, HT p , between the mean wave height, H, and the peak period, Tp, is well fulfilled. Though, the intensities of spectra tails do not follow the Toba’s ratio, 4 24p S()() f gu* f , rather they better correspond to the ratio S()(/)() f u** Xg gu f with p = 1/3. -
99 UPWELLING in the GULF of GUINEA Results of a Mathematical
99 UPWELLING IN THE GULF OF GUINEA Results of a mathematical model 2 2 6 5 0 A. BAH Mécanique des Fluides géophysiques, Université de Liège, Liège (Belgium) ABSTRACT A numerical simulation of the oceanic response of an x-y-t two-layer model on the 3-plane to an increase of the wind stress is discussed in the case of the tro pical Atlantic Ocean. It is shown first that the method of mass transport is more suitable for the present study than the method of mean velocity, especially in the case of non-linearity. The results indicate that upwelling in the oceanic equatorial region is due to the eastward propagating equatorially trapped Kelvin wave, and that in the coastal region upwelling is due to the westward propagating reflected Rossby waves and to the poleward propagating Kelvin wave. The amplification due to non- linearity can be about 25 % in a month. The role of the non-rectilinear coast is clearly shown by the coastal upwelling which is more intense east than west of the three main capes of the Gulf of Guinea; furthermore, by day 90 after the wind's onset, the maximum of upwelling is located east of Cape Three Points, in good agree ment with observations. INTRODUCTION When they cross over the Gulf of Guinea, monsoonal winds take up humidity and subsequently discharge it over the African Continent in the form of precipitation (Fig. 1). The upwelling observed during the northern hemisphere summer along the coast of the Gulf of Guinea can reduce oceanic evaporation, and thereby affect the rainfall pattern in the SAHEL region. -
Waves and Structures
WAVES AND STRUCTURES By Dr M C Deo Professor of Civil Engineering Indian Institute of Technology Bombay Powai, Mumbai 400 076 Contact: [email protected]; (+91) 22 2572 2377 (Please refer as follows, if you use any part of this book: Deo M C (2013): Waves and Structures, http://www.civil.iitb.ac.in/~mcdeo/waves.html) (Suggestions to improve/modify contents are welcome) 1 Content Chapter 1: Introduction 4 Chapter 2: Wave Theories 18 Chapter 3: Random Waves 47 Chapter 4: Wave Propagation 80 Chapter 5: Numerical Modeling of Waves 110 Chapter 6: Design Water Depth 115 Chapter 7: Wave Forces on Shore-Based Structures 132 Chapter 8: Wave Force On Small Diameter Members 150 Chapter 9: Maximum Wave Force on the Entire Structure 173 Chapter 10: Wave Forces on Large Diameter Members 187 Chapter 11: Spectral and Statistical Analysis of Wave Forces 209 Chapter 12: Wave Run Up 221 Chapter 13: Pipeline Hydrodynamics 234 Chapter 14: Statics of Floating Bodies 241 Chapter 15: Vibrations 268 Chapter 16: Motions of Freely Floating Bodies 283 Chapter 17: Motion Response of Compliant Structures 315 2 Notations 338 References 342 3 CHAPTER 1 INTRODUCTION 1.1 Introduction The knowledge of magnitude and behavior of ocean waves at site is an essential prerequisite for almost all activities in the ocean including planning, design, construction and operation related to harbor, coastal and structures. The waves of major concern to a harbor engineer are generated by the action of wind. The wind creates a disturbance in the sea which is restored to its calm equilibrium position by the action of gravity and hence resulting waves are called wind generated gravity waves. -
Coastal Risk Assessment for Ebeye
Coastal Risk Assesment for Ebeye Technical report | Coastal Risk Assessment for Ebeye Technical report Alessio Giardino Kees Nederhoff Matthijs Gawehn Ellen Quataert Alex Capel 1230829-001 © Deltares, 2017, B De tores Title Coastal Risk Assessment for Ebeye Client Project Reference Pages The World Bank 1230829-001 1230829-00 1-ZKS-OOO1 142 Keywords Coastal hazards, coastal risks, extreme waves, storm surges, coastal erosion, typhoons, tsunami's, engineering solutions, small islands, low-elevation islands, coral reefs Summary The Republic of the Marshall Islands consists of an atoll archipelago located in the central Pacific, stretching approximately 1,130 km north to south and 1,300 km east to west. The archipelago consists of 29 atolls and 5 reef platforms arranged in a double chain of islands. The atolls and reef platforms are host to approximately 1,225 reef islands, which are characterised as low-lying with a mean elevation of 2 m above mean sea leveL Many of the islands are inhabited, though over 74% of the 53,000 population (2011 census) is concentrated on the atolls of Majuro and Kwajalein The limited land size of these islands and the low-lying topographic elevation makes these islands prone to natural hazards and climate change. As generally observed, small islands have low adaptive capacity, and the adaptation costs are high relative to the gross domestic product (GDP). The focus of this study is on the two islands of Ebeye and Majuro, respectively located on the Ralik Island Chain and the Ratak Island Chain, which host the two largest population centres of the archipelago. -
Coastal Dynamics 2017 Paper No
Coastal Dynamics 2017 Paper No. 157 INTEGRATED MODELLING OF THE MORPHOLOGICAL EVOLUTION OF THE SAND ENGINE MEGA-NOURISHMENT Arjen Luijendijk1,2, Rufus Velhorst1, Bas Hoonhout1,2, Sierd de Vries1, and Rosh Ranasinghe2,3 Abstract This study presents some recent developments in coastal morphological modeling focusing on flexible meshes, flexible coupling between models operating at different time scales, and a recently developed morphodynamic model for the intertidal and dry beach. This integrated modeling approach is applied to the Sand Engine mega nourishment in The Netherlands to illustrate the added-values of this integrated approach. A seamlessly coupled modeling system for Delft3D and AeoLiS has been developed and applied to compute the first years of evolution of the Sand Engine, both for the subaqueous and subaerial areas. The subaqueous bed level changes have been computed with the new Flexible Mesh version of Delft3D, resulting in comparable accuracy levels as to the standard Delft3D version. The integrated morphodynamic prediction of both subaqueous and subaerial reveals a qualitative behavior which is very similar to observations. Model results confirm that after the first year after construction the sand supply for aeolian transports is predominantly from the intertidal area. The AeoLiS model results indicate a significant intertidal erosion volume of about 230,000 m3 over the five year period, which is a not to be neglected volume, especially in multiyear or decadal predictions. Interestingly, the model results show that the spit, developed by the wave-related processes, is also subject to aeolian transports acting on the emerged spit during lower tides. The seamlessly coupled models are now able to combine the dry beach behaviour with subaqueous morphodynamic evolution, which is important in medium-term to decadal morphodynamic predictions but also relevant for designing such sandy solutions incorporating lakes, lagoons, and relief. -
Third International Workshop on Sustainable Land Use Planning 2000
SEAVITT NORDENSON Landscape Research Record No. 4 STRUCTURES OF COASTAL RESILIENCE: DESIGN STRATEGIES FOR STORM RISK REDUCTION AT JAMAICA BAY, NEW YORK SEAVITT NORDENSON, CATHERINE The City College of New York, Spitzer School of Architecture, Program in Landscape Architecture, [email protected] 1 ABSTRACT This proposal for enhancing coastal resiliency at Jamaica Bay, New York consists of strategic design recommendations for the Rockaway Peninsula, the central marsh islands, and Back Bay communities. These recommendations, developed in a progressive academic research laboratory with the support of USACE, embrace the vast scale of Jamaica Bay as an asset for exploring USACE’s new focus on developing nature-based features as viable coastal storm risk reduction techniques. The Jamaica Bay resiliency plan includes three strategies developed through field research and modeling, both physical and digital. The first strategy addresses water quality and the reduction of back-bay flooding via a series of over wash plains, tidal inlets, and flushing tunnels at the Rockaway Peninsula and Floyd Bennett Field. The second strategy develops enhanced verges at Robert Moses’ Belt Parkway and elevates of coastal edges at vulnerable back-bay communities, managing flood risk with a layered system of marsh terraces, berms, and sunken attenuation forests. The third strategy develops novel techniques of bay nourishment and marsh island restoration through maximizing the efficacy of minimal quantities of dredged material. This “island motor / atoll terrace” would align with local cycles of maintenance dredging. Dredged material from maintenance dredging may be beneficially reused to nourish the Rockaways’ coastal beaches, enhance the bay’s marsh islands, and create living shorelines at the back-bay perimeter. -
The Influence of the Sand Engine on the Sediment Transports And
The influence of the Sand Engine on the sediment transports and budgets of the Delfland coast Analysis of bi-monthly high-resolution coastal profiles L.W.M. Roest Master thesis Hydraulic Engineering Front cover: Aerial photograph of the Sand Engine with Scheveningen in the background. Taken on 16 February 2016, by Rijkswaterstaat/Jurriaan Brobbel, https://www.flickr.com/photos/zandmotor/25106436435/ Back cover: Aerial photograph of the Sand Engine looking to the South. Taken on 16 February 2016, by Rijkswaterstaat/Jurriaan Brobbel, https://www.flickr.com/photos/zandmotor/25080093026/ The influence of the Sand Engine on the sediment transports and budgets of the Delfland coast Analysis of bi-monthly high-resolution coastal profiles Master Thesis For the degree of Master of Science in Civil Engineering at Delft University of Technology To be publicly defended on 17th August 2017 L.W.M. Roest 10th August 2017 Graduation committee: prof.dr.ir. S.G.J. Aarninkhof Delft University of Technology dr.ir. S. de Vries Delft University of Technology dr.ir. M.A. de Schipper Delft University of Technology dr. M.F.S. Tissier Delft University of Technology An electronic version of this thesis is available at http://repository.tudelft.nl/ Faculty of Civil Engineering and Geosciences (CEG) · Delft University of Technology Abstract The Sand Engine is a new innovation in coastal protection, a mega feeder nourishment. This pilot project was constructed in 2011 along the Delfland coast, which is historically prone to erosion. Since its construction, the Sand Engine is intensively being monitored to track the morphological development. The objective of this thesis is therefore to assess how the morphology of the Sand Engine is evolving over time and how this evolution contributes to the sediment budgets of the Delfland coast. -
Observations of the Sand Engine Pilot Project
Coastal Engineering 111 (2016) 23–38 Contents lists available at ScienceDirect Coastal Engineering journal homepage: www.elsevier.com/locate/coastaleng Initial spreading of a mega feeder nourishment: Observations of the Sand Engine pilot project Matthieu A. de Schipper a,b,⁎, Sierd de Vries a, Gerben Ruessink c, Roeland C. de Zeeuw b, Jantien Rutten c, Carola van Gelder-Maas d, Marcel J.F. Stive a a Faculty of Civil Engineering and Geosciences, Department of Hydraulic Engineering, Delft University of Technology, Delft, The Netherlands b Shore Monitoring and Research, The Hague, The Netherlands c Faculty of Geosciences, Department of Physical Geography, Utrecht University, Utrecht, The Netherlands d Ministry of Infrastructure and the Environment (Rijkswaterstaat), Lelystad, The Netherlands article info abstract Article history: Sand nourishments are a widely applied technique to increase beach width for recreation or coastal safety. As the Received 10 July 2015 size of these nourishments increases, new questions arise on the adaptation of the coastal system after such large Received in revised form 19 October 2015 unnatural shapes have been implemented. This paper presents the initial morphological evolution after imple- Accepted 30 October 2015 mentation of a mega-nourishment project at the Dutch coast intended to feed the surrounding beaches. In Available online xxxx total 21.5 million m3 dredged material was used for two shoreface nourishments and a large sandy peninsula. The Sand Engine peninsula, a highly concentrated nourishment of 17 million m3 of sand in the shape of a Keywords: fi Alongshore feeding sandy hook and protruding 1 km from shore, was measured intensively on a monthly scale in the rst 18 months Mega nourishment after completion. -
Building with Nature in Search of Resilient Storm Surge
Nat Hazards (2013) 65:947–966 DOI 10.1007/s11069-012-0342-y CONCEPTUAL NOTE TO THE EDITOR Building with Nature: in search of resilient storm surge protection strategies E. van Slobbe • H. J. de Vriend • S. Aarninkhof • K. Lulofs • M. de Vries • P. Dircke Received: 29 September 2011 / Accepted: 1 August 2012 / Published online: 13 September 2012 Ó Springer Science+Business Media B.V. 2012 Abstract Low-lying, densely populated coastal areas worldwide are under threat, requiring coastal managers to develop new strategies to cope with land subsidence, sea- level rise and the increasing risk of storm-surge-induced floods. Traditional engineering approaches optimizing for safety are often suboptimal with respect to other functions and are neither resilient nor sustainable. Densely populated deltas in particular need more resilient solutions that are robust, sustainable, adaptable, multifunctional and yet eco- nomically feasible. Innovative concepts such as ‘Building with Nature’ provide a basis for coastal protection strategies that are able to follow gradual changes in climate and other environmental conditions, while maintaining flood safety, ecological values and socio- economic functions. This paper presents a conceptual framework for Building with Nature E. van Slobbe (&) Alterra, Wageningen University and Research Centre, PO Box 47, 6700 AA Wageningen, The Netherlands e-mail: [email protected] H. J. de Vriend EcoShape Foundation/Deltares/Delft University of Technology, Burgemeester de Raadtsingel 69, 3311 JG Dordrecht, The Netherlands S. Aarninkhof EcoShape Foundation/Royal Boskalis, Burgemeester de Raadtsingel 69, 3311 JG Dordrecht, The Netherlands K. Lulofs School of Management and Governance, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands M. -
Guide Wave Analysis and Forecasting
WORLD METEOROLOGICAL ORGANIZATION GUIDE TO WAVE ANALYSIS AND FORECASTING 1998 (second edition) WMO-No. 702 WORLD METEOROLOGICAL ORGANIZATION GUIDE TO WAVE ANALYSIS AND FORECASTING 1998 (second edition) WMO-No. 702 Secretariat of the World Meteorological Organization – Geneva – Switzerland 1998 © 1998, World Meteorological Organization ISBN 92-63-12702-6 NOTE The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the World Meteorological Organization concerning the legal status of any country, territory, city or area, or of its authorities or concerning the delimitation of its fontiers or boundaries. CONTENTS Page FOREWORD . V ACKNOWLEDGEMENTS . VI INTRODUCTION . VII Chapter 1 – AN INTRODUCTION TO OCEAN WAVES 1.1 Introduction . 1 1.2 The simple linear wave . 1 1.3 Wave fields on the ocean . 6 Chapter 2 – OCEAN SURFACE WINDS 2.1 Introduction . 15 2.2 Sources of marine data . 16 2.3 Large-scale meteorological factors affecting ocean surface winds . 21 2.4 A marine boundary-layer parameterization . 27 2.5 Statistical methods . 32 Chapter 3 – WAVE GENERATION AND DECAY 3.1 Introduction . 35 3.2 Wind-wave growth . 35 3.3 Wave propagation . .36 3.4 Dissipation . 39 3.5 Non-linear interactions . .40 3.6 General notes on application . 41 Chapter 4 – WAVE FORECASTING BY MANUAL METHODS 4.1 Introduction . 43 4.2 Some empirical working procedures . 45 4.3 Computation of wind waves . 45 4.4 Computation of swell . 47 4.5 Manual computation of shallow-water effects . 52 Chapter 5 – INTRODUCTION TO NUMERICAL WAVE MODELLING 5.1 Introduction .