Beach Processes

This paper presents an analysis of field measurements to investigate the variability of empirical estimations of the longshore transport rate of a mixed beach, and is the first application of the impoundment technique to measure longshore transport rates on mixed beaches. The assessment is performed in terms of the coefficient “k” that is central to the CERC longshore transport equation. For this purpose, beach morphological changes were quantified applying an impoundment technique to act as a barrier to the sediments, while wave and tide data were also recorded during the same period. Beach profile data were analysed following two different methods. As a result, two distinct representative k coefficient values were obtained, one for the shingle profile and one for the mixed profile. Both values are in agreement with the published reduction of k for coarse grain sediments relative to sand. We also found a variation in k with wave conditions, in common with some earlier studies.

Beaches along the eastern branch of the Giens double tombolo are subject to coastal erosion. Prediction of the behavior of the beach profile configuration in response to natural and anthropogenic changes using the concept of equilibrium beach profile (EBP) could be useful in finding the most suitable measure to address the erosion problem. Field investigation data of 11 beaches along the eastern tombolo were supplied for this study, and a nonlinear fitting technique was applied to estimate the best parameter values of seven empirical formulations of the relevant EBP. All of the observed beach profiles could be described by a single function, but a single EBP was inadequate to represent all of the beach profiles observed. The variation found could be explained in terms of longshore variation of bathymetry, sediment size, and wave parameters. Analysis of the validity of the EBPs revealed that a representative EBP of each beach is governed by different equilibrium parameters.

This paper presents an analysis of field measurements to investigate the variability of empirical estimations of the longshore transport rate of a mixed beach, and is the first application of the impoundment technique to measure longshore transport rates on mixed beaches. The assessment is performed in terms of the coefficient “k” that is central to the CERC longshore transport equation. For this purpose, beach morphological changes were quantified applying an impoundment technique to act as a barrier to the sediments, while wave and tide data were also recorded during the same period. Beach profile data were analysed following two different methods. As a result, two distinct representative k coefficient values were obtained, one for the shingle profile and one for the mixed profile. Both values are in agreement with the published reduction of k for coarse grain sediments relative to sand. We also found a variation in k with wave conditions, in common with some earlier studies.

The overall form of many beach profiles has an exponential shape where the depth h is given by h = (Sj k)(l e b) with S,. the beach-face slope at x = 0 and k is an adjustable coefficient that determines the degree of concavity. The cross-shore variation in beach slope is then S = S"e "or S = S"-kh. Beach profiles can be analyzed in terms of both the cross-shore variations in hand S. Based on previous studies, the beach-face slope S" is predictable as a function of the sediment grain size and wave parameters. The evaluation of k can be based on best-fit comparisons with the measured profile depths or from bottomslope variations across the profile. Equations are derived for the evaluation of k from the offshore closure depth of the envelope of profile changes, or from some arbitrarily selected coordinate of the profile. An example of the analysis approach is provided by a beach profile from the Nile Delta coast of Egypt. This measured profile shows good agreement with the exponential form for cross-shore variations in both the absolute depth h and local bottom slope S. There is poor agreement with the h = Ax profile relationship. in part because this Nile Delta profile is more reflective and has a greater concavity than allowed by the x dependence. The failure of the x profile form is still more evident in analyzing the beach-slope variations since it predicts an infinite slope at the shoreline. The exponential beach profile is a convenient mathematical relationship that should be useful in many applications.

Estimation of Longshore Sediment Transport Rate (LSTR) in the littoral zone is essential for managing and developing any coastal zone. Numerical models are powerful tool to understand and investigate various processes responsible for LSTR in a systematic manner since direct measurement of LSTR is a difficult task. A one dimensional LITDRIFT model was implemented along the Vengurla coast for estimation of LSTR and to analyze the sensitivity of each input parameters towards the computation of LSTR. Major input parameters required for the estimation of LSTR are nearshore wave climate, bathymetry, and sediment characteristics. The nearshore wave data at a depth of 15 m were collected using wave rider buoy in 2015 is used in the present study. Field observations were carried out to survey the regional bathymetry and sediment characteristics. Annual net LSTR along Vengurala coast is relatively less and varies from ¡7778 to ¡9015 m 3 with an average of ¡8511 m 3. The net direction of LSTR is towards south and gross LSTR is 1.18 £ 10 5 m 3 /year. The LSTR reveals more sensitivity to coastline orientation and wave direction. A 1 changes in coastline angle and wave direction causes approximately 3000 m 3 /month difference in LSTR. Moreover, wave height, wave period, and bed roughness has an important role for controlling LSTR. The model results help to identify the role of each parameter contributing towards LSTR estimation and a similar model approach can be applied to other coasts for estimating LSTR in an accurate way.

This paper presents an analysis of field measurements to investigate the variability of empirical estimations of the longshore transport rate of a mixed beach, and is the first application of the impoundment technique to measure longshore transport rates on mixed beaches. The assessment is performed in terms of the coefficient “k” that is central to the CERC longshore transport equation. For this purpose, beach morphological changes were quantified applying an impoundment technique to act as a barrier to the sediments, while wave and tide data were also recorded during the same period. Beach profile data were analysed following two different methods. As a result, two distinct representative k coefficient values were obtained, one for the shingle profile and one for the mixed profile. Both values are in agreement with the published reduction of k for coarse grain sediments relative to sand. We also found a variation in k with wave conditions, in common with some earlier studies.

Wave-induced Longshore Sediment Transport (LST) play an important role in the dynamics of the Dhanushkodi sandspit located southeast of Rameshwaram. The LST along the Dhanushkodi coast is studied based on data collected simultaneously in Gulf of Mannar (GoM) and Palk Bay (PB) using directional waverider buoys. The numerical model REF/DIF1 was used to calculate the nearshore waves and the LST rate was estimated using three different formulae. The model validation was done based on the measured nearshore waves using InterOcean S4DW. Numerical model LITPACK was also used for simulating non-cohesive sediment transport and the LITLINE module was used to study the shoreline evolution over 5 years. Low net annual LST along PB (~ 0.01×10 6 m 3) compared to the GoM region (0.3×10 6 m 3) were due to the weak waves. Accretion in the region led to growth of the Dhanushkodi sandspit by 65 m during the period 2010-2015.

The accurate assessment of longshore sediment transport pattern along Nagapattinam-Poompuhar coastline bears significance due to the historical erosion and its geographical location adjoining the sheltered Palk Bay. Directional waves were measured off Nagapattinam coastline for one year to estimate the longshore sediment transport rate. It shows that the transport rate is relatively high about 0.1 X 10 6 rrr'/month in November and December and is low showing less than 0.03 X 10 6 mvrnonth in March, April and July. Though the annual gross transport is found to be 0.6 X 10 6 mvyear, the annual net transport is very low showing less than 0.006 X 10 6 mvyear (towards north), indicating the coastline tends to be a nodal drift regime. The temporary rise in wave activities during the cyclonic days often increases the southerly drift, which partly gets deposited in the Palk Bay and causes deficit for the northerly drift.

The accurate assessment of longshore sediment transport pattern along Nagapattinam-Poompuhar coastline bears significance due to the historical erosion and its geographical location adjoining the sheltered Palk Bay. Directional waves were measured off Nagapattinam coastline for one year to estimate the longshore sediment transport rate. It shows that the transport rate is relatively high about 0.1 X 10 6 rrr'/month in November and December and is low showing less than 0.03 X 10 6 mvrnonth in March, April and July. Though the annual gross transport is found to be 0.6 X 10 6 mvyear, the annual net transport is very low showing less than 0.006 X 10 6 mvyear (towards north), indicating the coastline tends to be a nodal drift regime. The temporary rise in wave activities during the cyclonic days often increases the southerly drift, which partly gets deposited in the Palk Bay and causes deficit for the northerly drift.

Rip currents have an important control on the exchange of water and advected materials such as sediment and pollutants, between the surf zone and inner shelf. Concurrent in situ Eulerian and Lagrangian (GPS drifter) data of surf zone waves and currents were combined with video data on wave breaking patterns over the inner and outer bars on a high energy, double-barred beach. The data collectively show how the occurrence of wave breaking over the outer bar changes the behavior of a channel rip current, and the exchange process. On both days, there was a prominent clockwise eddy in the surf zone, for which the seaward-heading portion formed a rip current in a well-defined channel rip, incised into the inner bar. Exit rate (measured with drifters) from the surf zone to inner shelf decreased significantly with increased wave breaking over the outer bar, from 71% exits to 6% over the two days. Exit rate appears to be driven by the balance between wave breaking over the inner and outer bars and pulsing of currents within the surf zone. Under higher wave conditions, there were stronger pulsations in surf zone currents and more surf zone exits. However, higher wave conditions caused wave breaking over the outer bar. This breaking increases vorticity around the outside of the surf zone eddy, which increases surf zone retention. This is in contrast to previous studies showing that vorticity is highest at the center of surf zone eddies. Under such conditions, drifter exits were rare, and occurred due to vortex shedding. During lower incident wave conditions, eddy vorticity was lower, and drifters could relatively freely exit the surf zone. This is one of the few studies that investigate surf zone circulation on a high energy, double-barred beach.

Coastlines are undergoing constant geomorphologic changes with respect to the incident wave climate. Based on waves measured at 9 m water depth, simulation of near shore wave transformation is done using REFDIF-1 numerical model and the near shore breaker parameters are estimated at two micro-tidal beaches along central west coast of India. Model results are validated with measured values. From the breaker parameters, longshore current and longshore sediment transport rates (LSTR) are computed by using semi-empirical equations. Estimated longshore current and LSTR are showing dramatic variations with respect to seasons. Predominant direction of LSTR is observed towards north since the approach waves are from south west direction during pre-monsoon and post monsoon. During monsoon season, waves are from west southwest and resulted in southerly transport. The estimated annual net and gross LSTR by CERC at two locations are in the same order whereas LSTR estimated by Walton & Bruno and Kamphuis equations are showing different estimations because of difference in surf-zone width and foreshore slope between the two locations. For micro-tidal beaches with length less than 6 km, Kamphuis equation is giving agreeable estimation of LSTR. Sensitivity analysis of LSTR estimate shows that coastal inclination is the prominent factor in determining LSTR than incident wave angle.

The need for quantitative assessments at a large spatial scale (103 km) and over time horizons of the order 101 to 102 years have been reinforced by the 2019 Special Report on the Ocean and Cryosphere in a Changing Climate, which concluded that adaptation to a sea-level rise will be needed no matter what emission scenario is followed. Here, we used a simple geometrical analysis of the backshore topography to assess the likely response of any wave-dominated coastline to a sea-level rise, and we applied it along the entire Great Britain (GB) coastline, which is ca. 17,820 km long. We illustrated how the backshore geometry can be linked to the shoreline response (rate of change and net response: erosion or accretion) to a sea-level rise by using a generalized shoreline Exner equation, which includes the effect of the backshore slope and differences in sediment fractions within the nearshore. To apply this to the whole of GB, we developed an automated delineation approach to extract the...

The modern technique of Coastal Engineering has enabled the succesful modification of the environment, the recuperation and the stabilization of those sandy areas which due to human action, were in a process of regression and erosion. This work developes a mathematical and numerical model to adjust and analyze the variations between the dissipative profiles and the reflectives ones. The research also emphasizes the enveloping profile to calculate the stable behaviour of the beach.

Beaches along the eastern branch of the Giens double tombolo are subject to coastal erosion. Prediction of the behavior of the beach profile configuration in response to natural and anthropogenic changes using the concept of equilibrium beach profile (EBP) could be useful in finding the most suitable measure to address the erosion problem. Field investigation data of 11 beaches along the eastern tombolo were supplied for this study, and a nonlinear fitting technique was applied to estimate the best parameter values of seven empirical formulations of the relevant EBP. All of the observed beach profiles could be described by a single function, but a single EBP was inadequate to represent all of the beach profiles observed. The variation found could be explained in terms of longshore variation of bathymetry, sediment size, and wave parameters. Analysis of the validity of the EBPs revealed that a representative EBP of each beach is governed by different equilibrium parameters.

The morphometric changes in coastal landforms can be related to the seasonal and spatial variation in wind velocity, wave energy, storm surges, and cyclonic phenomena along the coast of India. The west coast is marked with a broad and shallow continental shelf. It is subject to high storm surges, but smaller waves along the coast of Karnataka and Kerala in early monsoons, maximum morphological changes take place with high wave energy. During this period, most of the sediment material gets transported along the shore and gets preserved during the post-monsoon season. The gross sediment transport is low (5x10 5 m 3) along the west coast. While, the east coast of India with a narrow and steep shelf, produces high and powerful waves. Rivers, along their mouth region, discharge water and sediment explicitly as well, higher along east coast. The northeast monsoon brings high wave activity along the east coast, increasing the rate of sediment transport (15-20 x10 5 m 3). Meanwhile, the stretches of the east coast are subjected to severe storm surges and cyclonic storms during October-December. The calculated wave energy spectrum was used to identify the different wave systems present in the study areas. The present study determines the distribution of wave energy along the Indian coast and the associated coastal conditions.

The morphometric changes in coastal landforms can be related to the seasonal and spatial variation in wind velocity, wave energy, storm surges, and cyclonic phenomena along the coast of India. The west coast is marked with a broad and shallow continental shelf. It is subject to high storm surges, but smaller waves along the coast of Karnataka and Kerala in early monsoons, maximum morphological changes take place with high wave energy. During this period, most of the sediment material gets transported along the shore and gets preserved during the post-monsoon season. The gross sediment transport is low (5x10 5 m 3) along the west coast. While, the east coast of India with a narrow and steep shelf, produces high and powerful waves. Rivers, along their mouth region, discharge water and sediment explicitly as well, higher along east coast. The northeast monsoon brings high wave activity along the east coast, increasing the rate of sediment transport (15-20 x10 5 m 3). Meanwhile, the stretches of the east coast are subjected to severe storm surges and cyclonic storms during October-December. The calculated wave energy spectrum was used to identify the different wave systems present in the study areas. The present study determines the distribution of wave energy along the Indian coast and the associated coastal conditions.

The accurate assessment of longshore sediment transport pattern along Nagapattinam-Poompuhar coastline bears significance due to the historical erosion and its geographical location adjoining the sheltered Palk Bay. Directional waves were measured off Nagapattinam coastline for one year to estimate the longshore sediment transport rate. It shows that the transport rate is relatively high about 0.1 X 10 6 rrr'/month in November and December and is low showing less than 0.03 X 10 6 mvrnonth in March, April and July. Though the annual gross transport is found to be 0.6 X 10 6 mvyear, the annual net transport is very low showing less than 0.006 X 10 6 mvyear (towards north), indicating the coastline tends to be a nodal drift regime. The temporary rise in wave activities during the cyclonic days often increases the southerly drift, which partly gets deposited in the Palk Bay and causes deficit for the northerly drift.

Coastlines are undergoing constant geomorphologic changes with respect to the incident wave climate. Based on waves measured at 9 m water depth, simulation of near shore wave transformation is done using REFDIF-1 numerical model and the near shore breaker parameters are estimated at two micro-tidal beaches along central west coast of India. Model results are validated with measured values. From the breaker parameters, longshore current and longshore sediment transport rates (LSTR) are computed by using semi-empirical equations. Estimated longshore current and LSTR are showing dramatic variations with respect to seasons. Predominant direction of LSTR is observed towards north since the approach waves are from south west direction during pre-monsoon and post monsoon. During monsoon season, waves are from west southwest and resulted in southerly transport. The estimated annual net and gross LSTR by CERC at two locations are in the same order whereas LSTR estimated by Walton & Bruno and Kamphuis equations are showing different estimations because of difference in surf-zone width and foreshore slope between the two locations. For micro-tidal beaches with length less than 6 km, Kamphuis equation is giving agreeable estimation of LSTR. Sensitivity analysis of LSTR estimate shows that coastal inclination is the prominent factor in determining LSTR than incident wave angle.

The backshore zone is transitional environment strongly affected by ocean, air and sand movements. On dissipative beaches, the formation of ephemeral dunes over the backshore zone plays significant contribution in the beach morphodynamics and sediment budget. The aim of this work is to describe a novel method to identify ephemeral dunes in the backshore region and to discuss their morphodynamic behavior. The beach morphology is identified using Argus video imagery, which reveals the behavior of morphologies at Cassino Beach, Rio Grande do Sul, Brasil. Daily images from 2005 to 2007, topographic profiles, meteorological data, and sedimentological parameters were used to determine the frequency and pervasiveness of these features on the backshore. Results indicated that coastline orientation relative to the dominant NE and E winds and the dissipative morphological beach state favored aeolian sand transport towards the backshore. Prevailing NE winds increase sand transportation to the ...

The modern technique of Coastal Engineering has enabled the succesful modification of the environment, the recuperation and the stabilization of those sandy areas which due to human action, were in a process of regression and erosion. This work developes a mathematical and numerical model to adjust and analyze the variations between the dissipative profiles and the reflectives ones. The research also emphasizes the enveloping profile to calculate the stable behaviour of the beach.

Beaches are highly flexible structures that can be deformed by several reasons, some natural as wind and swell and others not, as human actions. Gravel, considered as a component of the beach is not always separated from the rest of the materials. It is a part of the coastline sedimentary balance, usually with time and spatial scales much greater than those corresponding to the stretch of the coast under study. The conceptual and experimental difficulties of studying this kind of beach have meant that nowadays they are really unknown. In this paper, methodologies to classify and determinate the most important characteristics in gravel beaches are presented. The authors have studied 34 shingle beaches in the region of Alicante (Spain) from a database with their characteristics. Obtained data corresponds to the morphology of the beach, the materials that take part in its composition and the wave energy, considering its incidence, the wave height, the local period and its influence on the coastline. At the beginning, mathematical models are generated, allowing the expression of the relationships between the slope of berm and the rest of variables. To classify the beaches, a factor analysis has been used on the experimental data matrix, considering all the variables as predictive, obtaining in this way an index for beach classification with similar characteristics. Furthermore, to determine the predictive variables that allow characterizing the 34 beaches, a discriminant analysis has been applied over several sets of variables. In each case, a predictive model of cluster belonging is created, considering a Coastal Cities and their Sustainable Future 297

Cocos Bay on the east coast of Trinidad comprises a barrier beach system that protects the Ramsar listed freshwater Nariva Swamp from the high energy environment of the Atlantic. The Manzanilla beach with its open bay morphology, and exposure to the Atlantic Ocean presents an interesting dynamic. There have been many developments in coastal geomorphology in terms of studying beach and nearshore changes. However, most studies on beach classification overlooked the dynamics of beaches in the Caribbean exposed to the Atlantic Ocean. Attempts to classify Manzanilla beach into the existing frameworks for beach state classification has proven to be problematic. This paper evaluates the applicability of such beach state classifications on beaches exposed to the Atlantic. Results indicate that an adjustment of the original limits for the dissipative beach domain is necessary in order to classify this beach. A Manzanilla dissipative domain is also proposed as a modification of the previous l...

Although, a variety of methods have been employed to determine sediment transport along Goa coast, the results differ in some sections. Fifteen studies have been reviewed, compared, re-assessed and a corrected shore drift map of the Goa coast is prepared and presented. Advantages and limitations of these methods are discussed. The present review and re-assessment confirms that, though sediment transport is bi-directional, the long-term net shore drift direction along Calangute and Colva beaches is southward. The overall net shore drift direction along Goa coast is also towards south. It is qualitatively determined that except for 3 short drift cells, shore zone has long-term stability. Finally, it is concluded that landform indicator study using remote sensing can be an effective method for determining long-term net shore drift along the coast.

This article presents an overview of investigations that were carried out to determine the dynamics of littoral transport along the west coast of India, during last three decades. Sedimentological methods, wave refraction diagrams, tracer tracking, geomorphic indicators etc. have been used for determination of littoral dynamics at various locations and along larger areas of west coast of India. Wave refraction studies have been conducted to determine locations of wave convergence and divergence, rip currents and to provide quantitative measurements of littoral drift and drift direction for local as well as regional areas. However, studies based on geomorphic indicators aided with remote sensing techniques were reliable to determine littoral drift cells and drift direction within each cell and net littoral drift direction along west coast of India. This review indicates that though littoral drift is variable, bi-directional and season dependent, long-term net littoral drift along wes...

Indonesia as one oftropical and archipelago countriesis daily illuminated by the sunlight.The integration of sunlight and earth pseudo-movement cause a dry and rainy seasons. The transition from one to another seasonoccur twice a year, which isMarch-May (first transition season) and September-November (second transition season). This research aim was to analyze the foreshore slope dynamic atCilacapcoast during the transitionseason. Data of slope dynamic were collected biweekly from March to May 2017 at 16 sites, where the distance of each site was 2 miles.The angle of slope was measured perpendicular to the shoreline using Theodolite,i.e. at the boundary of coastal vegetation, center site and foreshore waterline at low tide. The backshoreslope at four sites were increase at the second month and at the end of the transition seasonwas decline. The changes of foreshore slope at other siteswere decrease. The monthly dynamic of foreshore slope in the transitionseason underwent a narrow of change and different condition.The highest and lowest slope of the coast occurred on April (8%) and May (5.2%) consecutively. The transition season wasmostly influenced by the changes of wind pattern thatwouldaffect the ocean wave and the impacttobackshore slope was vary.The backshore slope changes were shown that more slopingat the end of the season. The transition season had an impact onbackshore slope and statistically, the monthly changes of coast slope weresignificant difference [p (0.05) ].

Shoreline change is considered the most dynamic processes in coastal region. Coastal erosion is a global problem where 70% beaches around the world are recessional. Almost all coastal area in Bali is potential to suffer from erosion. Badung Regency in Bali has many beaches that famous as tourism area where from about 64 km shoreline length, 11,5 km were recorded suffered by erosion in 1985 and 12,1 km erosion in 2007. This study aims to determine the value of shoreline changes that occur in western of Badung Regency from 2001 to 2010 based on the predicted wave data using monthly wind data from Ngurah Rai, Tuban, Badung, Bali meteorological station. Shoreline change simulation measured the forward (accretion) or backward (erosion) distance of the shoreline on the East-West direction. Bali has wind patterns that influenced by the Northwest monsoon from November-April and Southeast monsoon from May-October. In 2001-2010, dominant wind in this region was coming from east, southeast, and west. Geographically western coast of Badung influenced by incoming winds from the west, southwest, and south. Wind blow towards the coast in 2001-2010 are dominantly come from the west with wind speed range was about 1,7-4,7 m/s. Simulation indicated that generally shoreline tends to experience accretion in the north and erosion in the south. From 16000 m of study shoreline, along 7100 m of shoreline tend to suffer by erosion. Oppositely, along 8900 m of shoreline tend to have accretion.

This study applies some of the most practical longshore sand transport formulations and evaluates their adequacy to estimate the total (suspended and bed load) longshore sediment transport rate (LSTR) at Buarcos Beach, in the West coast of Portugal. The straightforward methodology here present is simple to apply and therefore useful to quickly obtain a first estimate of the littoral transport in coastal engineering studies. A sensitive analysis to the variation of hydrodynamic and morphologic parameters was performed. The most accurate prediction of the LSTR at Buarcos coastal region was obtained by the Kamphuis formulation derived in the last decade, which is recommended to be applied in similar hydrodynamic and morphodynamic conditions in the West coast of Portugal.

The Karnataka coast is subjected to high wave activity during the southwest monsoon when most of the sandy beaches undergo erosion. Based on the littoral cell concept, the Karnataka coast is broadly divided into 14 major littoral cells and 26 stations are selected in the present study. WaveWatch III global wave model data at 0.5°interval were used to derive the nearshore wave characteristics from XBeach numerical model. The model results were validated with the measured wave rider buoy data of the Indian National Centre for Ocean Information Services. The beach orientation, nearshore slope, median sediment size, significant wave height, mean wave direction, and the peak wave period were used in the estimation of longshore sediment transport rate. The mean significant wave height along the Karnataka coast was about 0.86 m, wave direction was about 210°and peak wave period was about 13 sec. The wave height during southwest monsoon (June-September) was higher, post-monsoon (October-December) was moderate and pre-monsoon (January-May) was the calmest period. Direction of longshore sediment transport was southwards during pre-and post-monsoons when waves were from the south-southwest. Whereas, northwards during monsoon when the wave approach from west-southwest to west. The annual net longshore sediment transport rate estimated was about 0.65910 6 m 3 towards the south and the sediment budget investigation depicts the loss of 0.067910 6 m 3 during the study period.

The rate of alongshore sediment transport in the surf zone  deponds  on the product of the local wave height and mean alongshore current speed. In this study, measurements of alongshore sediment transport rate have been carried out in the surf zone of Noor coastal area, in the southern part of the Caspian Sea during September 2011 to June 2012. Also alongshore sediment transport rate has been  estimated by different famous semi-empirical formulas.
As ANN models are capable of scrutinizing hidden laws of natural phenomena such as sediment transport process,to study the rate of longshore sediment transportan Artificial Neural Network (ANN) model was trained using three dominant parameters of sediment transport formulas including wave breaking height (H_b), surf zone width (W), and alongshore current velocity (V). The results of ANN model and some sediment transport rate formulas concerning alongshore sediment transport rate, were compared with corresponding measured values. The results show that the estimated value of alongshore sediment transport rate by CERC, Walton and Bruno, Kamphuis formulas and ANN model is 737.8 m^3/day ,670.3 m^3/day , 593.3 m^3/day and 592.4 m^3/day  , respectively. A according to the results, the calculated R^2 values, in estimation of alongshore sediment transport rate for ANN model and CERC, Walton and Bruno, and Kamphuis formulas, are 0.99, 0.98, 0.75 and 0.84, while the RMSE values are 4.7×10-4, 8.4×10-4, 9.1×10-2 and 1.4×10-3, respectively.

To understand the evolution and stability of beaches, prediction of the equilibrium beach profile (EBP) is theoretically and practically important. In the present paper, a new equation, h = Ae Bx + C is developed to predict the change in beach profile for sections above the water level and the adjacent nearshore portions. Moreover, fractal analysis is applied to predict types of EBP for the first time using the field data collected from Liao Zuikou and Nanwan beaches, South China. Three types of EBP termed Upward-concave EBP (U-EBP), Downward-concave EBP (D-EBP) and Medium-characteristic EBP (M-EBP), are given for the studied region of South China.

In a coastal region where there are large pressures on the beach resources through recreational usage, understanding the beach morphodynamic classification is paramount. On this basis, some selected beaches along Terengganu coastal region were chosen in order to determine its morphodynamic classification according to the indices modelled by Wright and Short (1984). As a result, the beaches at the northern and southern parts of Terengganu were classified as intermediate state while the middle part classified as reflective beach. Most of the beaches exhibited characteristics resulting from antecedent hydrodynamic conditions with stronger hydraulic forces at the middle region compared with the northern and southern beaches.

An analytical study to develop correlations between wave characteristics and longshore sediment transport along the perimeter of the Adra River Delta (Spain) has been carried out. Wave characteristics are based on visual data and buoy data. Five regions are defined along the delta in view of the grain size, which varies in range 0.33 < Ds0 < 2.0 (ram). Total sediment transport in each region is evaluated from aerial photographs covering a 30-year period. Calculated K values decrease with increasing Ds0. A diagram including results taken from other studies together with the present values is given. Although there are appreciable differences between the techniques followed to obtain the data, the diagram shows a consistent variation of K with Ds0.

The 26th December 2004 Indian Ocean tsunami devastated coastal regions of the Indian subcontinent. Andaman and Nicobar Islands, coastal stretches of Tamil Nadu, Andhra Pradesh and Kerala were the most affected regions of India. Changes in the beach profiles, long shore currents, breaking wave characteristics in the surf zone at selected locations along the Tamil sediment transport rates were estimated from the observed parameters. Studies were carried out earlier (1995-1996 and 1998) to understand the coastal environment over a one-year cycle in the study region. The post-tsunami observations were compared with the earlier studies to establish the variations in the littoral environment and to ascertain the normalcy of the littoral environment in the post-tsunami scenario. From the changes in the beach profiles, the shoreline was observed to recede by about 20 m and built-up of backshore by about 0.5 m at most locations. Observations from the field investigations and comparisons with earlier studies along this stretch of the coastline indicate that the coastline is yet to return completely to normalcy. r

Equilibrium profile is one of the conce pts in coastal geomorphology which is a result of the balance of destructive versus constructive forces. Two e quilibrium be ach profile models, viz. Bruun/Dean's twothirds power mode l and modified Bodge expone ntial model were used to analyse the measured post-monsoon (winter) beach profiles from three beaches in Goa having varying coastal morphology settings. The major factors that affect the equilibrium beach profile, viz. the me dian grain size (D 50 ) and the profile shape factor m, which are inve rsely proportional to each othe r, have been analysed for their application to the study site. Also, the variation of these two parameters with beach slope and grain size is studie d. Longshore sedime nt transport rates (LSTRs) are estimate d at these three beaches from the littoral environme ntal observations. LSTRs show that during winte r months, the net transport is of the orde r of 10.83  10 6 m 3 /year (southe rly transport) and 9.02  10 6 m 3 /year (southerly transport) respectively, at Candolim and Ke ri beaches, whe reas it is about 0.62  10 6 m 3 /year (northerly transport) at Miramar. This article discusses the methods used and results of measure me nts of beach morphology, LSTRs, analysis of equilibrium profiles and influe nce of various paramete rs relate d to equilibrium profiles.

Coastal dynamics represent change from time to time, could be the form of coastal presenting effect of sedimentation and earn also in the form of coastal backing effect of erosion. This research of coastal morphodynamics on Belang Bay, will study by some aspect that is: beach morphology, grain size sediment and hydrodynamics activity. The purpose of this study is to see how far the influence of the morphodynamics of the coastal damage and sensitivity (susceptibility) coastal sea water due to the influence of hydrodynamics. Method of data collection and analysis, two main parameters were measured wave energy and beach characteristics. Knowledge on the morphodynamic behavior of beaches was obtained from a topographic measurements of 15 beach transects normal to the coastline. Widely used morphodynamic parameters, like the Surf Similarity and the Surf Scaling parameters, were applied to the data, resulting in a general morphodynamic characterization of beaches, represented in a map of beach type distribution. In Molompar beach identified by sediment material vary between fine sand up to coarse sand which is distribution in each coastal circulation cell of Molompar beach.

Within the surf zone, the energy expended by wave breaking is strongly influenced by nearshore bathymetry, which is often linked to the character and abundance of local sediments. Based upon a continuous, two year record of Argus Beach Monitoring System (ABMS) data on the north shore of Kachemak Bay in southcentral Alaska, we model the enhancement of wave energy dissipation by the presence of intertidal sand waves. Comparison of model results from simulations in the presence and absence of sand waves illustrates that these ephemeral morphological features can offer significant protection to the backing beach and sea cliff through two mechanisms: (1) by moving the locus of wave breaking seaward and (2) by increasing energy expenditure associated with the turbulence of wave breaking.

""Cocos Bay on the east coast of Trinidad comprises a barrier beach system that protects the Ramsar listed freshwater Nariva Swamp from the high energy environment of the Atlantic. The Manzanilla beach with its open bay morphology, and exposure to the Atlantic Ocean presents an interesting dynamic. There have been many developments in coastal geomorphology in terms of studying beach and nearshore changes. However, most studies on beach classification overlooked the dynamics of beaches in the Caribbean exposed to the Atlantic Ocean. Attempts to classify Manzanilla beach into the existing frameworks for beach state classification has proven to be problematic. This paper evaluates the applicability of such beach state classifications on beaches exposed to the Atlantic. Results indicate that an adjustment of the original limits for the dissipative beach domain is necessary in order to classify this beach. A Manzanilla dissipative domain is also proposed as a modification of the previous limits set out by the dissipative domain.

Keywords: Cocos Bay, Manzanilla, dissipative domain, beach classification, morphodynamic indices.
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The process of erosion and accretion taking place along a stretch of coastline is governed by the geology of the area and the direction and strength of the wave attack. The Manzanilla beach is a very dynamic system owing to the open bay morphology, and being exposed to the Atlantic Ocean. The Las Cuevas beach is less dynamic, due to its embayed characteristic, and being open to the Caribbean Sea, a much smaller body of water. It is apparent that the interplay of coastal processes, sediment characteristics, and coastline orientation account for the variations in the intensity of the processes operating at each beach. The study seeks to explore the similarities and differences in processes at work in shaping these coastlines. This paper presents the data collected on coastal processes, sediment and morphological characteristics of both beaches.

"The shoreline monitoring component of the Coastal Conservation Project which commenced in 1988 provides valuable insights on the dynamics of the coastline. The scientific data are used by government and other agencies in formulating policies and plans for the coastline. While coastlines of Trinidad and Tobago are monitored under this project, this report presents only the research conducted in Trinidad during the period 2004 – 2008.  The report focuses on the 25 beaches and bays monitored, comprising 64 beach profiling stations. The report reveals that most of the beaches and bays in Trinidad are in a state of dynamic equilibrium where the seasonal changes of erosion and accretion occurring on the beaches revolve around a state of stability.
The beaches on the north coast are less prone to erosion due to the more resilient metamorphic rocks that form these bays. However, changes in sand elevations due to normal wave processes do occur. During the period 2004–2008 all beaches monitored on the north coast experienced a state of dynamic equilibrium with the exception of the east and west stations at Las Cuevas Bays and the western part of Blanchisseuse Bay.
All east coast beaches also experienced dynamic equilibrium except the southern part of Cocos Bay. Erosion in this part of the coastline threatened to breach the roadway and prompted government to construct a 2 km long rip rap revetment as a means of shoreline protection. This has curbed the erosion in the protected area but to the extreme south erosion is ongoing at a rate of 2.5 m/yr since 2005.
The beaches on the south coast experienced dynamic equilibrium except at the western section of Guayaguayare Bay.  Erosion in this part of the bay averaged 1.20 m/yr since 2004. This erosion can be attributed to both offshore and onshore open trenching for pipe laying activities.
The west coast beaches are located within the Gulf of Paria which provides a sheltered environment.  Erosion however was observed at North Chatham which averaged 1.20 m/yr since 2004.  Erosion was also observed at the western section of Guapo Beach in Clifton Hill during 2006 and 2007. On the south-western peninsula, while Punta del Arenal (Icacos) is experiencing accretion, Columbus Bay is being eroded. The erosion has prompted property owners to employ the use of coastal protection measures such as revetments and groins. This report makes recommendations for modifying the current monitoring regime as well as highlights further research needs.
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