Houston, J.R., 2017. Shoreline change in response to sea-level rise on Florida's west coast.

Shoreline position measurements about 300 m apart have been made along the Florida shoreline from the 1800s. There has been net shoreline advance during this time on the Florida E and SW coasts, but the Florida W coast has had net recession. Information is available on factors causing shoreline change on the Florida W coast, including sea-level rise, beach nourishment, loss of sediment to inlets, offshore dredged-sediment disposal, longshore sediment transport, and long-term, onshore sediment transport. Estimates are presented on the contributions these factors have made to shoreline change since the 1800s along 334 km of shoreline in seven west Florida counties. Summing the contributions results in net shoreline recession that agrees with measured recession within standard deviation confidence intervals in each of the counties and for the total shoreline. Sea-level rise is shown to have accounted for less than 20% of the magnitude of all shoreline change (including shoreline advance produced by beach nourishment). Projections of future shoreline change are made using sea-level rise projections of the Intergovernmental Panel for Climate Change (IPCC), along with projections of shoreline change that would be produced by each of the factors. It is shown that beach nourishment quantities at past rates can offset the recessional effects of sea-level rise for most IPCC sea-level rise projections from 2016 to 2065 and 2016 to 2100. A modest increase in nourishment can offset shoreline recession from sea-level rise based on the worst-case IPCC sea-level rise scenario.

Hill, P.S. and Gelati, S., 2017. Competent vs. observed grain size on the seabed of the Gulf of Maine and Bay of Fundy.

The output of a three-dimensional tidal circulation model and nearly 10,000 sediment samples are used to compare observed and competent grain sizes on the floor of the Gulf of Maine and Bay of Fundy. Competent grain size is the largest grain size a flow is capable of mobilizing. Competent and observed grain sizes have similar broad spatial distributions. Coarser observed grain sizes are found in regions of larger stress, and associated coarser competent grain sizes and finer observed sizes are found in regions with finer competent sizes. Areas in which competent sizes are finer than observed sizes likely have significant sources of seabed stress that are not included in the model, specifically from waves and subtidal flows. Areas in which competent sizes are coarser than observed sizes likely are regions where sediment input into the region overwhelms the ability of near-bed flows to transport sediment away from the region, leaving the seabed with a texture similar to that of the supply. The results indicate that sediment texture is unlikely to change greatly if large-scale tidal power development is pursued in Minas Passage, which connects the Minas Basin to the Outer Bay of Fundy. Forecast changes of sediment texture in the Gulf of Maine are small, and in the Bay of Fundy, sediment texture is unlikely to change because it is dominated by sediment supply, which should not be affected by tidal power development.

Benbow, C.A.; MacMahan, J.H., and Thornton, E.B., 2017. Analysis of surface foam holes associated with depth-limited breaking.

The behavior of surf zone foam holes, as observed at the surface and associated with depth-limited breaking, was investigated. Aerial imagery of the surf zone was obtained with a small, unmanned quadcopter that supported an integrated, high-resolution camera. The quadcopter is an ideal platform for acquiring images directly above the surf zone, a requirement to obtain the requisite resolution. The images were georectified so that size, shape, orientation, and evolution of the wave-generated foam patterns could be quantified. Three hypotheses are proposed for foam-hole generation: obliquely descending eddies (ODEs), self-organization because of bubble rise, and bottom-generated turbulent boils. The fringe region was the most seaward foam region and was marked with circular foam rings that increased in area and were more distinct with time. The fringe region data were consistent with both the self-organization because of bubble rise and turbulent boil mechanisms. The gap region, located between the plunge point and the splash-up created by the bore collapse, was marked by horizontal foam tubes oriented in the cross-shore direction. The foam tubes were likely created in the convergent region between two counter-rotating vortices. The largest region encompassed nearly the entire surf zone and was described as a mat of foam that developed obvious foam holes. The foam holes located in the outer surf zone, near the break point, initially decreased in size, consistent with ODEs before increasing in size and elongation. The foam holes located in the inner surf zone, increased in both size and elongation during a wave period. Because of increasing size with time, the foam-hole generation was attributed to turbulent boils. The rate of increase in foam-hole growth significantly decreased as the waves shoaled from the fringe region in the outer to the inner surf zone, suggesting that growth rate and size decreased with depth.

Evadzi, P.I.K.; Zorita, E., and Hünicke, B., 2017. Quantifying and predicting the contribution of sea-level rise to shoreline change in Ghana: Information for coastal adaptation strategies.

The purpose of this study is to estimate the contribution of sea-level rise (SLR) in Ghana over the last decades and provide an estimation of shoreline retreat due to the projections of regional SLR. This study first analyzes historical shoreline change in Ghana from 1974 to 2015 using satellite images and orthophotos. Second, this study quantifies the SLR contribution to historical shoreline change using sea-level trend estimates from satellite observations, results from digital elevation model analysis, and shoreline change rates. This study finally makes predictions of shoreline in Ghana on the basis of modified Intergovernmental Panel on Climate Change Fifth Assessment Report representative concentration pathways (RCPs) scenarios for Ghana. On average, sea level has risen by about 5.3 cm over the last 21 years and accounts for only 31% of the observed annual coastal erosion rate (about 2 m/y) in Ghana. On the basis of the projected model ensemble-mean rise in sea-level (2.6, 4.5, and 8.5 RCPs) scenarios and assuming that SLR will also contribute to 31% of shoreline retreat in the future, by the year 2025, about 6.6, 4.7, and 5.8 m of coastland in Ghana with lowest slope range (0–0.4%) are projected to be inundated respectively. These projected changes increase to 19.8, 20.7, and 24.3 m by 2050 and further to 36.6, 51.6, and 83.9 m by 2100 for the 2.6, 4.5, and 8.5 RCPs respectively. The analysis that separates sea-level contribution to coastal change from other contributing factors could provide useful information about climate impact for coastal adaptation strategies. This study, however, recommends further research into the anthropogenic and other factors that contribute about 69% of the annual erosion rate in Ghana to help improve adaptation efforts.

Díez, J.; Cánovas, V.; Uriarte, A., and Medina, R., 2017. Characterization of the dry beach profile: A morphological approach.

The dry part of the beach is probably the most extensively used part of the beach system. It comprises the zone from high tide level to the landward edge, which can be either a dynamic (dune field) or a fixed boundary (cliff, rocky ledge, or promenade). Here is presented a complete description of its morphology on the basis of the analysis of 91 study sites selected along the entire coast of Spain. The analysis comprises four different regions in terms of wave climate, geology, and tidal range, covering a wide range of coastal environments. In this study, a zonation of the dry beach profile is presented attending to the dynamics, the morphometric index, and the timescales of variation in which three different segments are defined: the foreshore segment, from the mean high water level to the berm, if present; the seasonal segment, which represents the zone between seasonal berms; and the interannual segment, which comprises the segment between the winter berm (or the most stable berm in case of no seasonality) and the landward edge of the beach. Besides, through cluster profile analysis—applying the K-Means classification algorithm to the entire data set of profiles—four types of dry beach profile are proposed, described, and related to a particular beach modal state: dissipative, intermediate, reflective, and ultradissipative. The observations and results presented here contribute to understanding the morphodynamics of the dry part of the beach and set the basis for subsequent studies concerning the equilibrium dry beach profile.

Horsch, G.M. and Fourniotis, N.Th., 2017. Wintertime tidal hydrodynamics in the Gulf of Patras, Greece.

Three-dimensional numerical simulations have been applied to simulate the winter barotropic hydrodynamic response that develops in the Gulf of Patras due to tidal and wind forcing. The simulations were performed using the code MIKE 3 flexible mesh hydrodynamic module. They reproduce already-known features of the tidal flow entering the Gulf of Patras from the Ionian Sea, such as reflection of the tidal wave at the Rio-Antirio Straits and the cove of the Bay of Nafpaktos. Furthermore, details of the flow structure are revealed, such as the gyre that develops during the transition from ebb to flood tide in front of the Messolonghi Lagoon and the gyre in the Bay of Nafpaktos from flood to ebb. The action of prevailing winds on tidal circulation is to create strong nearshore currents, which dictate the sense of rotation of gyres that develop nearshore at both the northern and southern shores of the gulf, when the wind opposes the tide. The exchange flow, which develops between the Gulf of Patras and the adjacent Nafpaktos Bay, was found to be dominated, in general, by the tide, rather than by the wind; this nevertheless creates a lag in exchange flow when the wind opposes the tide. Finally, tidal circulation was found to create upwellings during the wintertime regime, reported herein for the first time, at the same locations in the Gulf where upwellings are known to develop in the summertime baroclinic flow, although not under the same wind conditions.

Obraczka, M.; Beyeler, M.; Magrini, A., and Legey, L.F., 2017. Analysis of coastal environmental management practices in subregions of California and Brazil.

Globally, human and natural systems in urban coasts face multiple threats, most importantly from climate change. Increasingly, subnational state and local governments are being forced to include climate change impacts into coastal planning and management. Urban coastal managers are looking to more transparent and integrated coastal and environmental management regimes to better address the multiple stressors and uses, as well as to integrate public and stakeholder participation, and maximize a broad range of community economic and environmental and ecosystem benefits. This research presents a case study of coastal and environment management systems in two important coastal regions: an urbanized area of the central coast of California, United States; and the rapidly urbanizing and developing coastal lowlands of Rio de Janeiro, Brazil. Similarities and differences in coastal environmental governance, management, and outcomes were identified and analyzed. The contrasting federalist governance structures are compared, and the coastal management and environment assessment systems in the case study locations are analyzed. This research contributes to the body of knowledge on subnational coastal environmental management systems through the review of previous relevant studies; the examination of historical primary and secondary source official reports; and the collection, analysis, and discussion of important qualitative and quantitative interviews and survey data. The study concludes that transparency and accessibility to the decision-making process are essential to the success of coastal environmental management in both locations, with benefits arising from the presence of public participation and trust. The successful integration of broad stakeholders and public awareness in California provides an example that could possibly be replicable in Rio de Janeiro to increase stakeholder participation in the decision-making processes. The paper concludes with recommendations for further studies of governance and management alternatives, and for extending and strengthening state and local capabilities of coastal environmental processes within integrated coastal environmental management systems.

Chen, L. and Wang, W., 2017. Ecophysiological responses of viviparous mangrove Rhizophora stylosa seedlings to simulated sea-level rise.

As the only forests situated at the transition between land and sea, mangrove forests constitute one of the first ecosystems vulnerable to rising sea level. When sea-level rises, plants are exposed to increased salinity, as well as tidal flooding. The responses of mangrove forests to changing sea levels depend on the synergistic effects of tidal flooding and salinity on plants, especially plants at the seedling stage. Therefore, the aims of this paper were to assess the ability of viviparous mangrove Rhizophora stylosa Griff. seedlings to withstand tidal flooding given different seawater salinities, as well as to investigate the effects of tidal flooding and salinity on plant growth. To accomplish this, a mesocosm experiment was initiated to examine the synergistic effects of tidal flooding and salinity on the growth and physiology of R. stylosa samples subjected to seven tidal flooding times (0, 2, 4, 6, 8, 10, and 12 h simulated semidiurnal tide, twice daily) and two levels of water salinity (15 and 30 PSU [practical salinity units]) over the course of 100 days. Throughout the experimental period, R. stylosa seedlings exhibited the traits of flood-tolerant plants, including such mechanisms as high stem growth rate and leaf assimilation rate, as well as efficient utilization of carbohydrate reserves stored in hypocotyls of seedlings. The growth and physiological responses of R. stylosa seedlings were significantly affected by both salinity and flooding time. However, elevated salinity had less effect on growth and metabolism than simulated sea-level rise by the increase of flooding time. From these results, it can be concluded that R. stylosa at higher salinity exhibits competitive dominance and thus good adaptation of seedlings to future predicted rise in sea level, which could presumably result in niche shifting.

Patranella, A.; Kilfoyle, K.; Pioch, S., and Spieler, R.E., 2017. Artificial reefs as juvenile fish habitat in a marina.

This paper focuses on the use of small, inexpensive, artificial reef modules as replacement juvenile fish habitat within marinas. The research hypothesis was that the placement of small, structurally complex artificial reef modules would increase fish abundance and species richness relative to unmodified marina seawalls. Nondestructive visual surveys of fishes were completed monthly for 14 months for 12 artificial reef sites and 12 control (unmodified) sites within a small marina. Divers recorded species, abundance, and size class (0–2 cm, >2–5 cm, >5–10 cm, >10–20 cm, >20–30 cm, >30–50 cm, and >50 cm) for all sites. Data was statistically analyzed using analysis of variance and a post-hoc Student Newman-Keuls test. Total mean fish abundance and mean species richness were both significantly higher at artificial reef sites than at control sites. Analysis of mean abundance by size class found that the >2–5 cm, >5–10 cm, >10–20 cm, and >20–30 cm classes were significantly higher for artificial reef sites. Species richness analysis by size class found that classes >2–5 cm, >5–10 cm, >10–20 cm, and >20–30 cm were significantly higher at artificial reef sites. Fishes from the grunt (Haemulidae) and snapper (Lutjanidae) families contributed the most to the total abundance for both types of sites. These results support the research hypothesis and have vital implications for mitigating ecological impact to coastal fish nursery areas with the use of artificial structure.

Chun, H. and Suh, K.-D., 2017. Analysis of longshore currents with an Eulerian nearshore currents model.

In the present study, longshore currents are analyzed with the three-dimensional nearshore currents model in the Eulerian framework. It was found that the model was reduced to the classical one-dimensional longshore currents model for a long, straight, uniform coast, which could also be obtained from the Lagrangian nearshore currents model. It indicates that the longshore current velocities calculated by the Eulerian and Lagrangian models are equivalent to each other for a long, straight, uniform coast. In addition, it was shown that longshore currents with a parabolic vertical profile could be reproduced by the wave–current interaction term in the model. The analysis has been confirmed by the numerical experiments on DUCK94. According to the numerical experiment, the depth-averaged velocities from the present numerical model were consistent with those of one-dimensional longshore currents model at a significance level of 0.05. The present numerical model successfully predicted the parabolic profile of longshore currents outside the surf zone. However, the parabolic profile of longshore currents inside the surf zone was not shown in the present numerical results.

Vergara Dal Pont, I.P.; Caselli, A.T.; Moreiras, S.M., and Lauro, C., 2017. Recent coastal geomorphological evolution in the Negro River's mouth (41°S), Argentinean Patagonia.

This paper analyzes the geomorphological evolution of the Negro River's mouth to understand how aerodynamic and hydrodynamic states of the Atlantic coast have developed to this date. Accordingly, the morphometry of the beach and the historical river flow record were studied. The results indicate a dichotomous state for this coast. The SW area is characterized by cliffs with an average recession rate of 0.69 m/y during the 1959–2011 period, whereas the NE area is characterized by beaches in stable and accretion states. In the latter zone, a relatively fast coastal accretion was corroborated with the advance of a berm of up to 170 m between 1986 and 2014; furthermore, the beach extension grew to 760 m during 1986–2004. Since 1936, a completely new phenomenon was observed at the Negro River's mouth: the displacement and accretion of intertidal banks toward the coast provoked the closure of the channels of fluvial discharge and tidal currents. This activity at the Negro River's mouth could be due to the reduction of river discharge during the 20th century, which increased the preponderance of littoral current over the river discharge.

Low, L. and Anderson, C.J., 2017. The threat of a nonnative, invasive apple snail to oligohaline marshes along the northern Gulf of Mexico.

Aquatic invasive species continue to be a persistent ecological problem. Management of these species requires understanding of their impact and the conditions favorable for their occurrence. Pomacea maculata is an invasive, nonnative freshwater apple snail threatening wetlands through substantial herbivory. Recent detection of P. maculata in coastal Alabama has raised concerns regarding the susceptibility of estuarine marshes in Mobile Bay and the northern Gulf of Mexico. To evaluate this threat, mesocosms were created to examine snail response to the combined effects of salinity and plant species common to estuaries throughout the region. Over a 5-week period, snails in brackish-water mesocosms (∼10 parts per thousand [ppt], with Juncus roemerianus or Cladium jamaicense) became dormant and neither fed nor reproduced. Snails in freshwater mesocosms (<1 ppt, with Alternanthera philoxeroides or Sagittaria lancifolia) were active and exhibited herbivory, whereas snails in mixed salinity (∼5 ppt, with Typha angustifolia and Scirpus validus) exhibited some activity but minimal herbivory. In follow-up studies examining salinity and plant species individually, snails fed on palatable leaves in only freshwater and mixed salinity conditions. Further, snails in freshwater did not consume measureable amounts of S. validus, T. angustifolia, J. roemerianus, and C. jamaicense, suggesting that plant palatability of common estuarine plants may also restrict herbivory. From these results, managers are cautioned that estuarine marshes with low to mixed salinities and colonized by palatable plants may be susceptible to invasion by P. maculata.

Farhadzadeh, A. and Gangai, J., 2017. Numerical modeling of coastal storms for ice-free and ice-covered Lake Erie.

Lake Erie is the shallowest among the Great Lakes. Because of its shallow depth and because predominant wind direction in the area is along the lake's longitudinal axis, eastern and western Lake Erie experience significant storm surge that are usually followed by seiches. The lake warms in summer and quickly freezes over in winter when it often develops extensive surface ice. The surface ice, in turn, can modify wind setup and waves and even hinder wave propagation in areas where the surface ice is densely concentrated. In the following, a coupled numerical model for storm surge and wave is utilized for the simulation of Lake Erie coastal storms under ice-free and ice-covered lake conditions. Six extreme events, affecting both eastern and western Lake Erie, are selected for presentation here. A high resolution mesh is developed using the National Oceanic and Atmospheric Administration (NOAA) bathymetric data. The wind and pressure fields are developed for the selected storms based on the Climate Forecast System Reanalysis hindcast data and are used in the model as the primary forcing mechanism for the extreme events. For winter storms, the model is provided with temporally and spatially varying ice fields developed based on the NOAA Ice Atlas. Quantitative comparisons of spatial and temporal variations of simulated and measured storm surge and wave fields are presented. Furthermore, for the winter storms, the effect of ice cover on storm surge is assessed by comparing the model results for storm surge with actual ice-covered condition and the hypothetical ice-free condition.

Bollinger, M.A. and Kline, R.J., 2017. Validating sidescan sonar as a fish survey tool over artificial reefs.

Visual observation methods via SCUBA are commonly used to survey artificial reef fish, although conditions in the Gulf of Mexico often make surveys difficult or even dangerous for divers. In this study, sidescan sonar was used to quantify water-column fish abundance and was compared to the established visual observation methods on SCUBA over four reef sites. Calibrated intensity values measured from sidescan sonar echo returns were used to estimate fish body length and to calculate scaled biomass (g/m² reef) from a pooled fish length–weight relationship of commonly observed reef fish in the area. Sidescan sonar methods were equivalent to SCUBA surveys for measuring fish abundance over the same reef areas; however, overall reef-associated abundances measured with sidescan were significantly higher because the sidescan could measure a larger water-column area and furthermore allowed for a rapid assessment of abundance on a greater number of reefs in a single sampling day. Scaled abundance and biomass differed significantly between structural types, with the reefed oil-jacket structures in deeper, federally managed waters showing the highest scaled abundance and biomass. With sidescan methods, five reef sites could be surveyed in one day, demonstrating the capability for macroscale comparisons of fish abundance, biomass, and structural preference among sites.

Conde-Frias, M.; Otero, L.; Restrepo, J.C.; Ortiz, J.C.; Ruiz, J., and Osorio, A.F., 2017. Swash oscillations in a microtidal dissipative beach.

This paper evaluates the relationship between gravity and infragravity energy with swash oscillations as well as the model's ability to reproduce the transformation of the wave as it approaches the shore on a dissipative beach. For this purpose, numerical experiments were conducted in a dissipative beach from Cartagena, Colombia. Mean free surface measurements were carried out for 2 days in February 2014 by installing a cross-shore array of pressure sensors, as well as a Fourier analysis from these measurements to identify frequency components that characterize the waves and the energy associated with them. To implement the numerical modelling, the SWASH model (The Simulation WAves till Shore is a numerical model that resolves nonlinear shallow-water equations) was set up by using the bathymetric profile of Bocagrande Beach obtained during the field campaign. The results of this numerical modelling enabled the study of the infragravity energy growth mechanism and the evolution of gravity energy as the wave approaches the shore, as well as the relationship between gravity and infragravity energy with swash oscillations. Overall, the results show that the model is able to reproduce the significant wave height and significant wave height associated with infragravity energy; moreover, the model is able to accurately describe processes of energy dissipation and energy transfer. Furthermore, through a spectral analysis applied to the swash oscillations time series it was possible to find that saturation occurs at low-frequency significant swash height and high-frequency significant swash height as the significant wave height increases, since its increase is not linear with respect to the signficant wave height incident.

Yang, S.; Liu, X.; Liu, Q.; Guan, L.; Lee, J.M., and Jung, K.H., 2017. A study of storm surge disasters based on extreme value distribution theory.

In this study, a statistical model was set up using extreme value distribution theory to estimate the return periods for both the highest surge levels and the adjusted direct economic losses from storm surge disasters based on the historical database. The extreme value distribution theory has been widely applied in hydrology and coastal engineering, and one well-performing extreme distribution is the Gumbel distribution. Based on the Gumbel distribution, three parameter estimation methods were used to determine the best method for generating the Gumbel distribution functions; subsequently, the expressions for the return periods were derived. The least square method was identified as the best parameter-estimation method for this study. Comparisons were implemented among return periods of the highest surge levels with the adjusted direct economic loss, which showed that the linear functional relationship between these two indicators was not significant. This study also found there was strong spatial autocorrelation for the highest surge levels with the adjusted direct economic loss by employing spatial analysis along the China's coastline. Analysis based on comparisons among the return periods of the highest surge levels and the adjusted direct economic loss in three coastal regions showed different levels of return periods the regions tended to have. Furthermore, analysis of the variation in indicators between the former half and the latter half of the study period reflected the change in climate. The application of the extreme value distribution theory was extended to evaluate economic losses during a storm surge disaster, and the underlying relationships and the deviations between the highest surge levels and the adjusted direct economic loss were analyzed, which indicated the damages caused by storm surges did not completely depend on the surge level.

Saayman, M. and Saayman, A., 2017. How important are Blue Flag awards in beach choice?

South Africa's almost 3000-km coastline has long stretches of sandy beaches. An important yardstick for measuring their quality is the Blue Flag award, desired by beach and coastal management agencies. This paper investigates whether the Blue Flag status necessarily attracts a different beachgoer. It asks whether clear differences can be found between beachgoers at Blue Flag and non-Blue Flag beaches. Surveys of beachgoers were conducted during summer (March to April 2014) at six beaches near Cape Town and three near Mossel Bay. Four of these nine Western Cape beaches had Blue Flag status. The data from 374 completed questionnaires collected via random sampling were analysed using principal component analysis and logistic regression analysis. The results showed that seven beach-specific attributes attract beachgoers, with the most important ones being beach cleanliness and infrastructure. The results of the logistic regression showed that Blue Flag beachgoers are more likely to be locals, travelling in larger groups and who are motivated to visit the specific beach on the basis of attractiveness. They also regard visual beach cleanliness as more important. The paper has several findings, namely, it identified unique motives for travelling to a beach and it identified the attributes that mattered to beachgoers. It also highlighted the need for educational activities as well as environmental issues. Another important finding is a clear distinction between Blue Flag and non-Blue Flag beachgoers. This innovative study made a contribution in terms of literature and practise.

Hashim, M.; Aziz, M.F.H.A.; Hassan, R.B., and Hossain, M.S., 2017. Assessing target strength, abundance, and biomass for three commercial pelagic fish species along the east coast of Peninsular Malaysia using a split-beam echo sounder.

Decapterus maruadsi (round scad), Megalaspis cordyla (torpedo scad), and Selar boops (oxeye scad) are commercially important small pelagic fish species of Malaysia. Despite their commercial and ecological value, little is known about their target strength (TS), spatial and vertical distributions, and biomass estimates. A split-beam acoustic survey was performed in the east coast of Peninsular Malaysia (ECPM) in March–June 2009. The calibrated echo sounder allowed determination of TS, estimation of fish density (spatial distribution) and biomass, and produced density maps along depth gradients (vertical distribution). The TS–length relationships indicated that the logarithmic TS was proportional to the squared length. Additional water parameters that included salinity, temperature, and dissolved oxygen (DO) were collected to examine fish density changes in relation to water quality and depth. Results revealed that the small pelagic fish formed small schools that were scattered over a wide area of the ECMP; mean density varied between 1.1 and 1.9 t/km². The maximum fish density was in the spatial coverage between 102.875° E, 6.000° N and 103.125° E, 6.500° N. The mean total biomass was about 18,610 t. Optimum fish density was estimated around water depths between 40 and 60 m. Fish density mainly decreased with decreasing DO and with increasing depth. The demonstrated acoustic method can be used as a monitoring tool for national fish stock surveys.

Kolahdoozan, M.; Bali, M.; Rezaee, M., and Moeini, M.H., 2017. Wave-transmission prediction of π-type floating breakwaters in intermediate waters.

Floating breakwaters (FBs) are distinguished as an environmentally friendly type of breakwater that are more deployed in the development of small ports. Dissipation and reflection are the main mechanisms by which FBs protect the leeward side; however, because of the structure geometry, a portion of the incident wave energy is transmitted to the shoreline. Thus, the transmission coefficient (C_t), which stands for the transmitted portion of wave energy in comparison with the total wave energy, is an important parameter that describes the structure's efficiency. Only a limited number of studies have been performed for the description of wave energy that is transmitted in the intermediate waters; therefore, in this study, an attempt has been made to present a proposed formula for the prediction of C_t in intermediate waters. The proposed formula is based on the experimental measurements performed in the current study. The proposed formula was also evaluated using extra data. The correlation coefficients of 0.75 and 0.69 for the data set of this study and extra data from previous studies revealed that the proposed formula is more accurate than the previous formula provided for shallow and intermediate waters.

Yin, Z.; Jin, L.; Liang, B., and Wang, Y., 2017. Numerical investigation of wave reflection from a stepped breakwater.

On the basis of a combination of the Reynolds-averaged Navier–Stokes equations, standard k-ϵ equations, and volume-of-fluid technique, a two-dimensional mathematical model was used to investigate the wave reflection performance of a stepped breakwater. A series of experiments was conducted to measure the wave heights and validate the mathematical model, and they exhibited good agreement. The aforementioned mathematical model was used to compute composite wave heights for different still-water depths, incident wave heights, wave periods, single step widths, and stepped breakwater slope scenarios. The two-probes method was used to determine the incident and reflected waves from the records of composite waves. The results showed that the stepped breakwater slope (especially for the gentle scenarios) plays a dominant role in wave reflection, and the wave reflection coefficient increases with increasing slope. However, it decreases with the increase of relative width of a single step and incident wave steepness respectively. Using the Iribarren number and the relative width of a single step, a simple formula for wave reflection coefficient was developed on the basis of the dimensional analysis method. It was validated using the corresponding data.

Zheng, S.; Wang, A.; Mohmand, Y.T., and He, Y., 2017. Path optimum algorithm for container relocation problems in port terminals worldwide.

The container relocation problem (CRP) is concerned with emptying a cluster of identical containers stacked in one bay where every container is given a fixed extractive sequence with the fewest number of relocations. Such a typical problem has been examined in this paper. This research differs from previous studies in the following aspects: First, the retrieval paths of the CRP is proposed and its nondeterministic polynomial-time-hardness has been proved. Moreover, a mathematical model is presented that can provide the theoretical basis for the current research. Since the feasible retrieval paths are numerous, heuristic rules are presented to effectively reduce the resolution space. In addition, a new path optimum algorithm (POA) based upon heuristics is proposed to find the optimal solution for any-scale instances in a shorter central processing unit run time. Numerical experiments and comparisons with the other algorithms from the literature show the superiority, high efficiency, robustness, and accuracy of this algorithm. As competition among coastal and inland container ports has become fierce, POA can be used to increase port handling efficiency and facilitate the decision making regarding container port infrastructure planning, and contribute to coastal research worldwide.

Chang, C.-H.; Wang, K.-H., and Hsieh, P.-C., 2017. Fully nonlinear model for simulating solitary waves propagating through a partially immersed rectangular structure.

In this study, a two-dimensional fully nonlinear wave model is developed to simulate a solitary wave propagating through the surface of a partially immersed rectangular structure. The analysis includes the transient characteristics of the evolving waveforms throughout the process of wave-structure interaction. The potential-flow–based finite difference model is generalized by solving the transformed equations in grids according to a vertically transient curvilinear coordinate system. The fully nonlinear conditions at the free surface are treated by a mixed explicit-implicit scheme to ensure numerical accuracy and stability. The wave elevations in terms of reflected and transmitted waves under various structural and wave conditions are computed and compared with those from a series of small-scale experimental tests. Good agreement for results of selected cases is also confirmed by comparison with other published experimental measurements and integrated analytical-numerical model (IANM) solutions. It is found that both the structural length and the positioned gap greatly affect the wave reflection, transmission, and wave runup at the front and rear walls of the structure. For a structure with more complex geometry, simulations of a solitary wave passing through a partially immersed body with an excavated bottom are also performed. The excavated zone is shown to suppress the transmission process of the incident waves.