Obeysekera, J. and Park, J., 2013. Scenario-based projection of extreme sea levels.

Heavily populated urban centers and natural areas located in low-lying coastal regions are highly vulnerable to sea-level extremes. Historical data at many tide gages suggest that changes over time in extremes generally follow the rise in mean sea level. Assuming this observation to hold in the future, a relationship between mean sea-level rise and its associated extremes with a generalized extreme value distribution can provide future return levels of extreme sea levels. Current projections of future sea level, which include varying degrees of acceleration, may result in large increases in extremes that need to be accounted for in the evaluation of existing coastal projects or in the planning of new ones. Because precise quantitative estimates of the uncertainties in sea-level rise projections are not available, scenario-based approaches have been suggested for project evaluation and design. Here, we propose a general method based on the synthesis of extreme value statistics with sea-level rise scenarios that allows any combination of linear or nonlinear local and global sea-level rise components and can accommodate the nonstationary evolution of sea-level extremes. The temporal variation of the design level of protection for coastal projects, expressed as the return period of extreme events, and the future behavior of the risk are explored. The concepts are demonstrated through application to tide gage data at several locations in the United States.

Gelinas, M.; Bokuniewicz, H.; Rapaglia, J., and Lwiza, K.M.M., 2013. Sediment resuspension by ship wakes in the Venice Lagoon.

Observations of Bernoulli wakes were recorded and analyzed for 22 passing ships in the industrial Malamocco–Marghera shipping channel in the Venice Lagoon. The wakes were characterized as a progressive N-wave with a dominant, leading trough preceded and followed by small crests. As the wake traveled, water transport under the trough was initially opposite the direction of wake propagation, sending resuspended sediment back toward the channel. Water velocities were documented to reach more than 2 m s⁻¹ under the trough, and suspended sediment concentrations exceeded 380 mg L⁻¹. Sediment loads were successfully predicted from measurements of current speeds, settling speeds, and sediment flux determined as a function of bottom shear stress. Resuspension rates reached several thousand milligrams per square meter per second. The size of the wake, and the amount of resuspension it can cause, might be parameterized by a nonlinear combination of a blocking coefficient S and a depth-based Froude number F; both parameters depend only on the channel geometry and ship's dimensions and speed. In this case, both the depth of the trough and the maximum suspended sediment concentration depended on S^1.6F^3.5.

Li, H.; Lin, L., and Burks-Copes, K.A., 2013. Modeling of coastal inundation, storm surge, and relative sea-level rise at Naval Station Norfolk, Norfolk, Virginia, U.S.A.

The potential risk and effects of storm-surge damage caused by the combination of hurricane-force waves, tides, and relative sea-level-rise (RSLR) scenarios were examined at the U.S. Naval Station, Norfolk, Virginia. A hydrodynamic and sediment transport modeling system validated with measured water levels from Hurricane Isabel was used to simulate two synthesized storms representing 50-year and 100-year return-period hurricanes, a northeaster, and five future RSLR scenarios to evaluate the combined impacts of inundation on this military installation in the lower Chesapeake Bay. The naval base topography and nearshore water body of Hampton Roads were included in the coastal modeling system (CMS), a suite of surge, circulation, wave, sediment transport, and morphology evolution models. The modeling domain was a rectangular area covering the entire Naval Station Norfolk in the Hampton Roads and the mouths of the James and Elizabeth rivers. A variable-resolution grid system was created with a finer resolution of 10 m in the naval base and a coarser resolution of 300 m in the regions away from the base. The boundary-forcing conditions to the CMS were regional storm surge produced by the ADvanced CIRCulation (ADCIRC),and wave conditions by the Simulating WAve Nearshore (SWAN) model. The CMS calculated the local water-surface elevation and storm-surge inundation for combined RSLR, surge, waves, and wind. Results indicate that synthetic storms would cause extensive inundation of coastal land around the naval base. Approximately 60% of the land would be under water with the 100-year storm for the present sea level, and 80% for estimated RSLR of 2 m.

Li, H.; Lin, L., and Burks-Copes, K.A., 2013. Modeling of coastal inundation, storm surge, and relative sea-level rise at Naval Station Norfolk, Norfolk, Virginia, U.S.A.

Tropical cyclone impacts on wetland, terrestrial, and shelf systems have been previously studied and reasonably delineated, but little is known about the response of coastal lakes to storm events. For the first time tropical cyclone impacts on a shallow coastal lake in the Louisiana coastal plain have been studied using direct lines of evidence. Using side-scan sonar, CHIRP subbottom, and echo sounder bathymetric profiles, the lake bottom and shallow subsurface of Sister Lake was imaged pre- and post-Hurricanes Katrina and Rita to provide a geologic framework for assessing storm effects. Box cores were collected to provide site-specific “ground truth” data to further evaluate the accretion or erosion of sediment over the short storm period between synoptic geophysical surveys. X-ray radiographs of box cores showed clear increments of recent event sedimentation (1–10 cm in thickness), corroborated with radionuclide dating as being products of the storm period. High percentages of approximately 40% fine sand in the storm layer and its thickness relative to an average long-term sedimentation rate of 2.0 mm/y suggest that transport of storm-related sediments from the inner shelf is a large factor in Sister Lake sedimentation. This study provides a framework and fundamental understanding of lake bottom characteristics and impacts of storm-related physical processes on erosion, sediment resuspension, and deposition. For a general case of subsidence in the Louisiana coastal plain of 6–8 mm/y and future sea-level rise rate of at least 3 mm/y, the sediment deficit for Sister Lake is 7–9 mm/y, which suggests that Sister Lake will deepen and widen with time.

Breaker, L.C. and Ruzmaikin, A., 2013. Estimating rates of acceleration based on the 157-year record of sea level from San Francisco, California, U.S.A.

The question of the acceleration of global sea level rise has gained increasing attention because the present rate of sea level rise is relatively small in comparison to the rates that are predicted to occur in the near future. Recent measurements have come under scrutiny on how to correctly analyze and interpret regional estimates of acceleration. In this context, we employ the Ensemble Empirical Mode Decomposition (EEMD), a data-adaptive method developed for the analysis of nonstationary and nonlinear data to estimate acceleration over the 157-year record of sea level from San Francisco, California. We define sea level acceleration (SLA) as the mean of the second differences of the residual from an EEMD. Using the residual provides a means by which to reduce or eliminate the contaminating influence of decadal and longer-period oscillations in sea level that are folded into estimates obtained using the conventional approach. For the entire record, a value of 0.011 ± 0.003 mm/y² was obtained for the acceleration and its uncertainty, compared with 0.013 mm/y², using the conventional approach. The effect of record length is examined by estimating the accelerations for truncated versions of the record, one starting in 1900 and a second in 1925. The accelerations differed in each case from the conventional values, as expected, because the methods are based on different definitions of SLA.

Prizomwala, S.P.; Shukla, S.B.; Basavaiah, N., and Bhatt, N., 2013. Provenance discrimination studies on sediments of the SW Kachchh coast, western India: insights from heavy mineral and mineral magnetic analysis.

Studies of the SW Kachchh coast, along the western coast of India, including granulometry, heavy mineral content, and mineral magnetic properties for sediment characterization, were undertaken to fingerprint probable source attributes. Heavy mineral analysis showed that the westernmost location received its dominant contribution from Indus-derived sediments (61%), whereas in the easternmost locations, the hinterland/Kachchh mainland–derived sediments dominated, with 79% of the total heavy mineral concentration. Mineral magnetic properties also showed that sediments derived from the fluvial system of the Kachchh mainland were rich in low-coercivity magnetic minerals with distinct multidomain (MD) grain size and were dominantly ferrimagnetic mineral assemblages (S-ratio  =  0.92–1.0), whereas at the western end, the concentration of magnetic minerals was low, with a dominant stable single domain (SSD) size range and antiferromagnetic minerals dominating the magnetic mineral assemblages (S-ratio  =  0.57–0.9). The granulometry, heavy mineral content, and mineral magnetic properties characterize different segments and multiple end members contributing to the coastal setup of the Gulf of Kachchh, India.

Meccia, V.L.; Simionato, C.G., and Guerrero, R.A., 2013. The Río de la Plata estuary response to wind variability in synoptic timescale: salinity fields and salt wedge structure.

The Río de la Plata estuary response to wind variability in a synoptic timescale is studied with the Estuarine, Coastal and Ocean Model forced by tides, runoff, and idealized winds. Ancillary conductivity, temperature, and depth data from synoptic oceanographic cruises are used to validate the conclusions derived from the simulations. Results show that the estuary's response to wind variability can be explained in terms of four characteristic patterns associated with winds that blow with a dominant component either along or across the estuary axis. Cross-estuary winds from the SW produce a northward displacement of the surface salinity front toward the Uruguayan coast and cause downwelling between Montevideo and Punta del Este. Reciprocally, under NE winds, the surface salinity front migrates to the SW and upwelling between Montevideo and Punta del Este occurs. Along-estuary winds with a downstream component produce a net outflow of continental surface waters and inflow of bottom shelf waters, resulting in an intensification of the stratification. In opposition, winds with an upstream component produce a weakening of the vertical structure. Stratification can be destroyed by strong or persistent SE winds, which are not frequent in the region, and it recovers in a relatively short period (10–15 days) after wind relaxation. Consequently, the salt wedge structure is observed in the Río de la Plata during most of the year. This implies that significant vertical mixing events producing exchanges of water and properties between the surface and the bottom waters occur only a few times a year. As a consequence, the Río de la Plata shows strong retentive features, favoring biota by retaining eggs and larvae—and favoring pollutant accumulation.

Erginal, A.E.; Ekinci, Y.L.; Demirci, A.; Avcıoğlu, M.; Öztürk, M.Z.; Türkeş, M., and Yiğitbaş, E., 2013. Depositional characteristics of carbonate-cemented fossil eolian sand dunes: Bozcaada Island, Turkey.

Coastal eolianite on the south coast of Bozcaada Island, Turkey, was investigated by field observations, petrographic and climatological examinations, and electrical resistivity tomography data. The 4- to 7-m-thick eolianite, including rhizolith morphotypes characterized by root tubules and bifurcated root casts, demonstrates dune-sand accumulation during the Upper Pleistocene. Our results showed that paleowind drift and recent windblown sand drift on the island are similar. The dune sands exhibit various cement types formed of calcite and aragonite, such as micrite encrustations, meniscus and gravitational cements, and in particular, void fills. Dune-sand accumulation took place on the truncated surface of Miocene deposits. Geophysical data showed the existence of large weathered cavities within the eolianite and a high-angle normal fault, which displaces the eolianite, together with the underlying Miocene unit.

Kirby, R.E. and Widjeskog, L.E., 2013. Sediment redistributed by coastal marsh mosquito ditching in Cape May County, New Jersey, U.S.A.

Effects of mosquito ditching on salt-marsh sediment budgets have not been quantified for lack of sufficient records, but such information is necessary to provide historical context for current management objectives. We were able to do so in Cape May County, New Jersey, where Mosquito Extermination Commission records reported 1,493,900 m³ of spoil redistributed through ditching from1902 to1974. The amount of spoil redistributed rose to 2,240,850 m³–22,987,800 m³ overall when ditch-cleaning efforts were included. On a 54-km² study area, 161,560 m of ditches removed as much as 99,000 m³ of material. If all such sediment stayed in the system and was deposited in open water, it would have added 0.082 mm/y to those areas. If the sediments had accumulated only in the larger water bodies, it would have been sufficient to add 0.16 mm/y to those areas. Alternatively, if the material had been deposited only on the marsh surface, the material displaced by mosquito ditching was capable of adding only 0.036 mm/y. These rates are inconsequential in a system infilling at a rate of 4.4–7.4 mm/y. Materials released by mosquito ditching thus have added to the sediment budgets of this coastal system, but shoaling of bays and sounds in recent centuries is a consequence of increases in all sediment sources including many of anthropogenic origin. Nonetheless, other consequences of ditching to the marsh (e.g., increased drainage, transport of water, and erosion of ditch banks) are not negligible in consideration of all anthropogenic effects. These data can help parameterize models of salt-marsh accretion in the face of climate change.

Yao, Y.; Huang, Z.H.; Monismith, S.G., and Lo, E.Y.M., 2013. Characteristics of monochromatic waves breaking over fringing reefs.

A fringing reef is a reef that is directly attached to a shore. Since fringing reefs resemble plane beaches in some aspects, it is important to understand the similarities and discrepancies between the wave breaking over fringing reefs and the wave breaking over plane beaches. With an idealized fringing reef (a plane sloping fore reef and a submerged horizontal reef flat), a series of laboratory experiments were conducted in a wave flume to understand how the reef-flat submergence and the fore-reef slope may affect the characteristics of wave breaking over fringing reefs. The results show that the relative reef-flat submergence (the ratio of the reef-flat submergence to the wave height) is an important factor to characterize most wave-breaking features (the breaker type and location, the surf-zone width, and the incipient breaker depth index). The influence of the fore-reef slope appears to be insignificant in our experimental conditions. The findings in this study can be used to calibrate or improve some existing analytical or numerical models developed for cross-shore wave transformation, wave-induced setup and wave-driven flow over fringing reefs.

Lonard, R.I.; Judd, F.W., and Stalter, R., 2013. The biological flora of coastal dunes and wetlands: Distichlis spicata (C. Linnaeus) E. Greene.

Distichlis spicata (C. Linnaeus) E. Greene is a New World temperate-, subtropical-, and tropical-zone rhizomatous, dioecious grass. It is an important species in coastal salt marshes, brackish marshes, and tidal wetlands, where it is often a dominant species. Inland ecotypes of this taxon occur in wet alkaline sites throughout temperate regions of the United States, Mexico, and South America. Distichlis spicata often occurs in wetlands, where total soluble salts seasonally range from about 20 to 43 ppt and where the pH varies from 5 to 7. Higher salinities in the rhizome–root matrix reduce shoot growth more than root growth. Also known as salt grass, D. spicata is a clonal stress tolerator that spreads laterally into disturbed sites in the upper marsh, and it recovers quickly from burial by wrack debris after storms. A typical water level range for salt grass is from 10 to 15 cm below to 5 cm above the marsh surface, but it can tolerate tidal amplitudes ranging from 1.36 to 1.74 m for 1 hour on some coastlines. Pistillate plants typically dominate lower elevations in tidal marshes, whereas higher elevations in marshes support populations dominated by male plants. Herein, we present a review of the biology of this important species.

Baker, R.G.V. and McGowan, S.A., 2013. Geographic information system planning for future sea-level rise using evidence and response mechanisms from the past: a case study from the Lower Hunter Valley, New South Wales.

One of the greatest challenges of coastal land-use policy is predicting future rates of sea-level rise from different proposed climate change scenarios. This study uses evidence from past higher Holocene and Pleistocene shorelines in southern Australia to develop possible response functions for future sea level modelling. A rule-of-thumb is determined by comparing rising sea levels of the past from relic intertidal biological markers with Antarctic temperature fluctuations during the mid-Holocene. The result is that for every 1°C increase in Southern Hemisphere relative temperatures, there would be, on average, a 0.9-m positive response in mean relative sea levels. Spectral analysis, comparing mean sea-level records from Sydney, Australia; the Southern Hemisphere temperature anomaly data (1850 to 2011); and Antarctic temperature fluctuations from the last 7000 years suggest that there are significantly longer (∼20 y and ∼50 y) periodicities that must be accounted for in any accurate determination of projections for 2100. For southern Australia, past sea-level rise appears to be in phase with Antarctic temperature changes and possible meltwater surges, suggesting that the use of linear sea-level rates per year, whilst convenient for planning, may be physically misleading. The policy response from the past should be a precautionary principle, based on centennial envelopes, capturing possible intermittent rapid surges that can be punctuated by decadinal stillstands. Three past–present–future (PPF) sea-level scenarios are applied to a case study of an area surrounding the Hexham Swamp, Newcastle, Australia. An impact infrastructure audit is undertaken, using a light detection and ranging geographic information system relative to multiple PPF centennial sea-level rise envelopes, to plan in this context for future sea-level rise.

Nebel, S. H.; Trembanis, A.C., and Barber, D.C., 2013. Storm frequency and barrier island erosion rates, Cedar Island, Virginia.

Shoreline surveys, high-resolution satellite imagery, aerial photography, and topographic maps were compiled using GIS and analyzed with the Digital Shoreline Analysis System to examine event- and decadal-scale patterns of shoreline movement related to tropical cyclone impacts on south Cedar Island, Virginia. Global Positioning System (GPS) shoreline surveys conducted on southern Cedar Island 1.5 months before and 3 weeks after Tropical Storm Ernesto in 2006 recorded shoreline movement that resulted from the storm. On average (arithmetic mean), the southern section of Cedar Island retreated 25.4 ± 1 m as a result of the storm. The most severe erosion was documented to the south of an ephemeral inlet where the shoreline retreated 54.8 m. Shoreline recovery in the study area was determined from a February 2007 aerial photoset and a June 2007 GPS shoreline survey. Between September 2006 and February 2007, the shoreline accreted an average of 7.4 ± 2.1 m. Between February 2007 and June 2007, the shoreline eroded an average of 0.2 ± 2.1 m. The comparison of the July 2006 (pre-Ernesto) and June 2007 (9 months after Ernesto) data revealed that the shoreline had not recovered to its poststorm position but rather had undergone net erosion averaging 18.3 ± 1 m. Additionally, the 155-year record (1852–2006) of Cedar Island shoreline retreat was compared with the historical record of tropical cyclones passing within 200 km of the Delmarva Peninsula. A marked acceleration in island retreat rates began in 1980 and continued until the end of the study period in 2007. This acceleration in island erosion rate coincided with an increased frequency of tropical cyclones within the studied region.

Orton, T.G.; Lark, R.M.; and Sasaki, J., 2013. Using geostatistics to analyze prediction errors from a simulation model of sediment particle sizes across Tokyo Bay.

Buildup of sediment on the seabed of Tokyo Bay has had an impact on water quality and ecosystems in the bay. Process models have been built to simulate the mechanisms governing sediment buildup, but such models are useful only if they can be validated against measurements obtained from the study area. Visual comparison of maps produced by the process model with measurements can provide some information about the ability of the process model to simulate the spatial variation of sediment buildup, but we consider a more rigorous geostatistical approach to perform this validation task. We consider predictions by process simulation models of the median particle diameter (MPD) of sediment across Tokyo Bay; we use a geostatistical approach to test whether the process model provides useful information for explaining the spatial distribution of 95 MPD measurements from the bay. Furthermore, we use the geostatistical approach to investigate the spatial distribution of model errors and to test whether there is evidence that errors could be explained by other environmental variables. The aim of the study is to demonstrate the kind of information we can get from such a geostatistical analysis of model output and errors, without looking directly inside the process simulation model. This information could subsequently be used to assist research into further simulation model developments.

Peterson, C.D.; Cruikshank, K.M.; Darienzo, M.E.; Wessen, G.C.; Butler, V.L., and Sterling, S.L., 2013. Coseismic subsidence and paleotsunami run-up records from latest Holocene deposits in the Waatch Valley, Neah Bay, northwest Washington, U.S.A.: links to great earthquakes in the northern Cascadia Margin.

Representative shallow cores (1–2-m depth) from the Waatch Valley (n = 10) and from Neah Bay back-barrier wetlands (n = 7) record four coseismic subsidence events and associated paleotsunami inundations during the last 1300 years in the North Central Cascadia Margin. Three of the subsidence events (SUB1, SUB2b, and SUB3) correlate to reported great earthquakes dated at AD 1700, about 1.1 ka, and about 1.3 ka. An additional subsidence horizon (SUB2a), which is newly discovered in the study area, might correlate to a widely reported paleotsunami inundation, dated between 0.7 and 0.9 ka in the study region. The magnitudes of paleosubsidence in the Waatch Valley are modest (about 0.5−1.0 m), as based on macofossil evidence of abrupt wetland burial. Paleotsunami origins of the four landward thinning sand sheets are confirmed by the presence of ocean diatom taxa and beach sand grains. Long wave run-up in the low-gradient Waatch floodplain ranged from 2.5 to 4.5 km up-valley distance from the present tidal inlet shoreline. Paleotsunami overtopping of the Neah Bay barrier ridge (6–8-m elevation North American Vertical Datum of 1988 [NAVD88]) provides the first estimates of paleotsunami minimum run-up height at the entrance to the Juan de Fuca Strait.

González, P.; Lluch-Cota, S.E., and Nava-Sánchez, E.H., 2013. Relation between the structure of mangrove forests and geomorphic types of lagoons of the Baja California Peninsula.

There are limited studies involving geomorphic factors and ecological patterns on a landscape scale of coastal features. This study examines the hypothesis that the structure of mangroves varies with habitat type. Using geomorphic criteria, we identified and classified 51 lagoons that contain mangroves on the Baja California Peninsula. Four lagoon types were analyzed: open drowned valley (I-A), barred drowned valley (I-C), Gilbert de Beaumont barrier lagoon (III-A), and cuspate lagoon (III-B). Structure patterns of mangrove forests growing at the edge of the lagoons were identified through photo interpretation and field observations, using landscape indices related to (1) area, density, and variability of the patches; (2) ecotone; and (3) form. Multivariate and univariate analyses were performed to determine the effects of habitat types on mangrove structure. Cluster analysis based on structural similarity showed two groups: (A) forests with limited structural development that grow mostly at the shore of lagoons I-A and I-C, and (B) larger forests with numerous patches, larger average size, average perimeters, and simpler forms than those in the first group, which grow mostly in lagoon type III-A. Similarity analysis showed no differences between the forests of lagoon types I-A and I-C, but there were differences between these two types and type III-A. Variance analysis showed differences in area, perimeter, and the shape of patches with respect to habitat type. Tukey's Honestly Significant Difference post hoc tests confirmed previously identified groups and showed that forest patches in lagoon type III-B are of intermediate structure. Lagoon type III-A appear to be more important in distribution and development of mangrove forests. Finally, we found that the spatial scale analyses and use of geomorphologically defined habitats were effective approaches for a first-order differentiation of mangrove forests.

Pan, Y.; Li, L.; Amini, F., and Kuang, C., 2013. Full-scale HPTRM-strengthened levee testing under combined wave and surge overtopping conditions: overtopping hydraulics, shear stress, and erosion analysis.

Post–Hurricane Katrina investigations revealed that most earthen levee damage occurred on the levee crest and landward side slope as a result of wave overtopping, storm surge overflow, or a combination of both. This study was conducted to investigate the hydraulic parameters and erosion characteristic of one levee strengthening technique, a high-performance turf reinforcement mat (HPTRM), under combined wave and surge overtopping conditions, about which little is known. Because the HPTRM system can only be tested using a full-scale model, a full-scale laboratory study on combined wave and surge overtopping of a levee crest and landside slope strengthened by the HPTRM was conducted in a two-dimensional laboratory wave/flow flume. The overtopping hydraulic features were summarized during the tests. The time series of flow thickness and velocity at five locations on the levee crest and landside slope were measured. Soil erosion and stem and blade loss were measured during the test intervals. New empirical equations were developed to estimate the average overtopping discharge. Based on the distribution of the overtopping discharge, combined wave and surge overtopping was divided into two cases: a surge-dominated case and a wave-dominated case. New equations were developed to estimate the mean flow thickness, root-mean-square wave height, mean velocity, and velocity of the wave front on the landside slope. The shear stress and average overtopping velocity on the landside slope and levee crest were calculated. The characteristics of soil loss and grass stem and blade loss on the HPTRM-strengthened levee were given. A “maximum soil loss” was found for each measuring point.

Hasan, G.M.J.; van Maren, D.S., and Hin Fatt, C., 2013. Numerical study on mixing and stratification in the ebb-dominant Johor Estuary.

A three-dimensional hydrodynamic model is used to investigate intratidal spring-neap variations of turbulent mixing and stratification in the Strait of Singapore and its adjacent Johor estuary area. The waters in the Johor estuary are ebb dominant because of interaction of the O1–K1–M2 tidal constituents. In most estuaries mixing rates during the flood are larger than during the ebb because of a flood-dominant tidal asymmetry. The Johor estuary is an example where tidal asymmetry supports stronger mixing during ebb tides, whereas similar to other estuaries, tidal straining promotes stable stratification during the ebb. Therefore an analysis of intratidal variation in stratification reveals the relative importance of both mechanisms. Vertical profiles of salinity, flow velocity, and eddy diffusivity show a marked asymmetry between flood and ebb tides. Small changes in the tidal currents substantially influence the eddy diffusivity, energy dissipation rate, and build up of stratification, which is explained using the nondimensional Richardson number. The estuary is found completely mixed during flood tide and slightly stratified during ebb tide, suggesting tidal straining (generating ebb stratification) is more important for the intratidal variation in mixing and stratification than tidal asymmetry (flood stratification).

Barbaro, G. and Foti, G., 2013. Shoreline behind a breakwater: comparison between theoretical models and field measurements for the Reggio Calabria Sea.

Longshore sediment transport is affected by coastal structures, which cause phenomena such as the erosion and deposition of sediments. These phenomena may also occur at locations far from the coastal structure. The prediction and management of shoreline evolution are necessary to protect coasts; they should take into account both long-term and short-term effects and should consider the presence or absence of coastal structures. In this paper several models that predict shoreline evolution behind a breakwater have been analyzed. The results of the predictions have been compared with real shoreline evolution measured in the Natural Ocean Engineering Laboratory (NOEL) in Reggio Calabria, where an experiment concerning the possibility of converting wave energy into electricity using a particular device placed in a breakwater is being investigated. A breakwater was installed in March 2005 and is still there, and it has altered the natural coastal processes affecting the shoreline profile. Comparisons were made in June 2005 (3 months after the installation of the breakwater) and in September 2010. The results indicate that the shoreline profile is not symmetrical about the centerline of the structure, but the salient (the point where advancement is prominent) is displaced toward the south side such that erosion is deeper on the north side.

Avcıoğlu, M.; Erginal, A.E.; Kiyak, N.G.; Kapan-Yeşilyurt, S., and Yiğitbaş. 2013. A preliminary note on depositional characteristics and optical luminescence age of a marine terrace, Strait of Çanakkale, Turkey

This preliminary study investigated the depositional features and optical luminescence age of marine terrace sediments located on the east coast of the Strait of Çanakkale, Turkey. With regard to depositional setting, the studied sequence is formed mostly of shallow marine deposits rich in quartz and oysters as well as other accessory minerals and various fossil sea shells. In vertical section, the sequence is characterized by two different stratigraphic units, i.e. a 1.50-m-thick sandy to gravely bottom unit (unit A) and an overlying 2.5-m-thick fossiliferous zone (unit B). On the basis of optically stimulated luminescence (OSL) age estimations obtained from six sampling levels from bottom to top, we determined superimposed cycles of deposition during interglacials from 246.47 ± 25.32 ka (unit A) at MIS 7 to 127.48 ± 8.91 ka (unit B) at MIS 5.

González Trilla, G.; Pratolongo, P.; Beget, M.E.; Kandus, P.; Marcovecchio, J., and Di Bella, C., 2013. Relating biophysical parameters of coastal marshes to hyperspectral reflectance data in the Bahia Blanca Estuary, Argentina.

Salt marshes occupying the tidal fringe of estuaries and protected coasts provide valuable ecosystem services, and remote sensing is a powerful tool for their large-scale monitoring. However, in order to apply remote sensing techniques to evaluate the ecological state of salt marshes, a deeper understanding is needed about the interactions between field biophysical parameters and the sensor's reflectance. The main objective of this work is to analyze and quantify the influence of different biophysical parameters characterizing stands of Spartina alterniflora marshes in the Bahia Blanca Estuary, Argentina, on their spectral response. Spectral reflectance at high resolution was measured in S. alterniflora canopies under natural conditions, manipulating standing biomass by means of successive harvestings. Reflectance data were acquired using a FieldSpec® spectroradiometer, which measures in the visible, near-infrared, and shortwave-infrared spectral bands. Based on these reflectance data, spectral indices such as the normalized difference vegetation index (NDVI) were calculated for each biomass condition. Biomass, leaf area index (LAI), percent canopy cover (PCC), water content, and soil properties were also evaluated. LAI, PCC, and biomass were positively correlated between each other. As a general trend, as biomass decreased, absorption in red wavelengths decreased and reflectance in near-infrared increased. Several indices explained the variability in LAI, biomass, and PCC. For example, NDVI_Rouse had a positive regression with PCC (R² = 0.80, N = 75) and LAI (R² = 0.67, N = 75). Results indicate that LAI, biomass, and PCC of Spartina alterniflora could be accurately determined from spectral data.