A generalized methodology, relevant for a wide variety of shoreline change analyses, is developed to estimate the horizontal offset between proxy-based high water line (HWL) type shorelines and datum-based mean high water (MHW) type shorelines. The ability to compute this term is critical for change analyses that incorporate variously defined and derived shoreline estimates because this horizontal offset nearly always acts in one direction; HWL shorelines are landward of MHW shorelines. Not accounting for this offset will cause shoreline change rates to be biased toward slower shoreline retreat, progradation rather than retreat, or faster progradation than in reality (for the typical case where datum-based shorelines are collected after proxy-based shorelines), depending on actual changes at a given site. It is also demonstrated that by computing the uncertainty associated with this proxy datum shoreline bias, we are quantifying, for the first time, the uncertainty of HWL shorelines due to water level fluctuations. Complete accounting of the uncertainty of shoreline position estimates is necessary for determining the statistical significance of shoreline change rate computations. The proxy-datum bias and the bias uncertainty are estimated to be approximately 18 and 9 m, respectively, on average for the sandy beaches of the California coast (and significantly larger on the milder sloping beaches of the U.S. Pacific Northwest). The importance of accounting for the bias in calculating shoreline change rates is confirmed as its inclusion along the California coast changes the coastwide decadal-scale (1970s to present) shoreline change rate from net progradation to net shoreline retreat.

This study has depicted a scenario on assessing spatial and temporal land use/cover changes in and adjacent to marine protected areas (MPA) in a study site in Thailand. The measurement of landscape stability and its implications for protection and conservation of coastal resources are emphasized in this study. The methods employed include interpretation and analysis of satellite images, aerial photographs, and geographic information system (GIS) data. Image analysis and GIS techniques have been used extensively, and a site-specific geospatial database was developed accordingly. Initial temporal changes inside and outside protected areas are captured from visual interpretation of three time series satellite images, where an increase of aquaculture ponds and abandoned areas is clearly visible. The output changes derived from the image differencing techniques demonstrated considerable changes in the whole study area as well as inside the protected area boundary during 1976 to 1990. Compared to the earlier time (1976–1990) the changes during 1990 to 2005 are found to be less extensive. Although the existing marine protected areas were declared earlier than the 1990s, the changes are still found inside the protected area boundary during 1990–2005. The result shows significant increases in agriculture areas, including aquaculture development, which are, however, less inside the protected areas than the buffer areas. While mangrove areas have noticeable negative changes, an increase in Malalueca forest areas is interesting. In the discussion, a quantitative comparison of legislative boundary and buffer effects on protecting land use and land cover is illustrated. In light of existing ecological context and socioeconomic activities, observations are made on agents of change and resource use conflicts.

The thermoluminescence (TL) properties of feldspar were used to investigate the sediment movement processes in a fluvial–coastal system. Field samples were collected at various locations along the Tenryu River and the Enshunada Coast in Japan. After a series of pretests, an appropriate TL measuring sequence was proposed for this study. Applying this approach, the natural TL intensity of feldspar grains was measured. Owing to the young age of the research area, it was assumed that the natural TL difference was ascribed to the sample depositional environment under which different possibilities of sunlight exposure exist. Surface sediment particles in the target area were classified into three groups in terms of TL intensities, i.e., river sand with large TL signals, coastal sand with medium TL signals, and dune sand with small TL signals. Stratified configuration of the Nakatajima Coastal Dune was observed from the underground-sample TL glow curves with a top, windblown, dune-sand layer; a bottom, wave-induced, coastal sand layer; and a mixing layer in between. A rather complex sediment-movement pattern in front of the Tenryu River mouth was revealed after investigation of the underwater samples. Because of the seawater influence, acting as an ultraviolet filter to sunlight, underwater samples present a larger, high-temperature TL peak than the low-temperature peak; whereas these two are almost the same for ground samples.

Study of the characteristics of currents and water-level variations in the Cochin estuary reveals, for the first time, unique signatures of mixed standing-waves in the southern region. Analysis of the simultaneous water-level data generated at the mouth of the estuary, located about 45 km upstream, showed very little dissipation had taken place in the tidal amplitudes, implying that tides are amplified because of a physical barrier. The amplitudes of the major tidal constituents O₁, K₁, M₂, and S₂ were 87, 87, 83, and 79%, respectively, of the values close to the sea. The M₂ tide was found to be the maximum, followed by the K₁, S₂, and O₁ constituents. Sea level was found to be largely forced by the astronomical tides at both the locations. The nontidal time series at the two locations correlated strongly, with the percentage of the variance explained by the relationship being about 82.3%. Currents and their displacements were found to be of low magnitude but revealed significant spatial variability, even though they were closely spaced. As compared with the cross-shore currents, the alongshore currents were highly coherent, with clear signatures of tidal forcing. Further, tidal analysis of synchronous data on various parameters—water level, alongshore and cross-shore currents, temperature, and salinity—revealed the relative dominance of the various tidal constituents. The water temperature peaked during late afternoon, suggesting solar forcing, whereas salinity variation, though quite low in range, showed signatures of tidal forcing. A scatter plot of water level and spatial average of alongshore currents revealed correlations of minima in overtide velocity amplitudes. The magnitude of the currents was very small and not proportional to the tidal heights observed. Intense mixing is closely related to the horizontal velocity shear, which causes mixing sufficient to destratify the water column. Resonance of the M₂ tidal wave may be possible because of the length and depth relation in the estuary, and the results suggest overtides are the causative factor.

From July 2003 to June 2004, the physiographic characteristics of the ichthyofauna of the estuary of Saco da Fazenda were studied in four defined areas representative of the estuary. A total of 4502 individuals were captured, with 42 species, 35 genera, and 21 families. Engraulidae were the most abundant fish, and Cetengraulis edentulus dominated the captures. The species of occasional occurrence prevailed in the samplings and were represented mainly by juvenile individuals. The highest abundances occurred during the months of summer and autumn, in contrast with high biomasses in the spring and autumn; area IV contributed the largest captures. The richness indexes, diversity, and equitability presented similar flotation patterns, with high values in spring and summer. The Jaccard index revealed a greater similarity in the composition of the ichthyofauna in areas II and IV, while the lowest happened between I and IV, which is probably due to the different sizes of these areas.

This paper clearly shows the relevance of this estuary, albeit strongly impacted, for recruitment of small fish mainly during summer and autumn months.

Deltas and clinoforms are accretionary deposits with subaerial and subaqueous topsets, respectively. Various factors have been proposed that may control their geometry, especially the interaction of sediment supply and physical oceanographic energy. A conceptual model of how this interaction affects shelf sedimentation indicates that sediment from most rivers should form deltaic features in quiescent environments. In more energetic settings, most sediment from small rivers (sediment load of 10⁶–10⁷ t/y) should be dispersed, limiting significant shelf accumulation, but the increased supply from larger rivers (sediment load of 10⁸–10⁹ t/y) could allow for sediment retention on the shelf, leading to clinoform development. However, in the Adriatic Sea, a river delta and a shelf clinoform (i.e., adjacent to the Po River and the Apennine rivers, respectively) have developed from similar sediment supply and oceanographic energy. This suggests that other factors are likely important, particularly differences in the shelf gradient and the timing of floods and storms. The shelf gradient is lower near the Po River, favoring retention of sediment in shallower water as compared to the Apennine rivers. In addition, floods and storms are uncorrelated on the Po River shelf due to the large size of the drainage basin, enhancing sediment deposition in shallow water. For the Apennine rivers, the drainage basin of individual rivers is small, and floods and storms are generally correlated, facilitating offshore deposition of sediment and leading to the development of a shelf clinoform.

This research deals with the probabilistic simulation and assessment of erosion in the downstream maritime slopes in hop ports (ports with deep approach channels to be able to accommodate the recent vessels generations) with natural side slopes. The study concentrated on the liquefaction effect in the erosion factor, which is the main controllable parameter for this phenomena. The probability of failure for the limit state function represents the erosion factor, which has a liable representation by a normal distribution with parameters μ = 2.63 and σ = 1.69, as a representative limit state function. This research deals with a maritime channel with certain dimensions as an example. The probabilistic simulations for downstream slope erosion were carried out using the Monte Carlo technique by using a probabilistic model. The generated probabilistic histograms of the erosion factor based on one run and different numbers of simulated random samples were determined. Based on these reliability simulation results, the erosion volumes per unit width of the channel were evaluated. Validation and sensitivity analyses were also carried out to ensure more reliability for this research.

The study produced a group of guiding regression models for estimates and the determined conclusions related to the evaluated erosion volumes we carefully examined by considering calculation conditions based on a 95% confidence level with different assumptions. Then preliminary estimates for the eroded volumes (m³/m) in the downstream slope of the channel were evaluated and so used to determine the relevant regression models. These distributions were determined based on a group of assumed realistic conditions, which include variable berm depths and constant downstream slope angles in one simulated group with erosion volumes against downstream slopes depths heights variation and constant berm depths and variable slope angles in another with erosion volumes against downstream slopes angles variation. The limit state functions representing the erosion volumes variation behavior under the different conditions were also determined by using reliable statistical goodness-of-fit software. The research results are presented in a graphical form for the purpose of improving the current application capabilities in the subject and providing practical usage for the unprotected maritime navigation channel, trenches, and maritime downstream slopes.

Time-frequency techniques to characterize cuspate patterns in light detection and ranging (lidar) data are introduced using examples from the Atlantic coast of Florida, United States. These techniques permit the efficient study of beach face landforms over many kilometers of coastline at multiple spatial scales. From a lidar image, a beach-parallel spatial series is generated. Here, this series is the shore-normal position of a specific elevation (contour line). Well-established time-frequency analysis techniques, wavelet transforms, and S-Transforms, are then applied to the spatial series. These methods yield results entirely compatible with the traditional method of estimating the spacing of cuspate features. In addition, confidence intervals are readily established for the spatial extent and wavelengths of cuspate landforms simultaneously at multiple scales. Examples show this method is useful for capturing transitions in cuspate shapes. With the advent of land-based time-lapse lidar, such techniques should be particularly useful for characterizing the evolution of cuspate landforms and testing models for beach face dynamics.

Mixed sand and gravel beaches form a wedge of protective sediment at the base of eroding cliffs. In profile these beaches are typically steep with a prominent storm berm. If the volume of beach sediment is insufficient, storms strip beach sediments seaward, exposing the cliff toe to wave attack. The beach volume is thus crucial to the protection of sea cliffs. In this article we describe a method of calculating alongshore variation in the volume of mixed sand and gravel beaches using ground penetrating radar (GPR). Eighteen sites were studied along 50 km of the east coast of South Island, New Zealand. The method was underpinned by an ability to map the boundary between beach sediments and underlying Pleistocene alluvial-fan sediments. This was achieved by studying the radar facies, particularly landward-dipping overwash deposits and seaward-dipping beach erosion surfaces. The method was ground-truthed in three ways: (1) a stream provided a clean section through one site that was imaged by radar; (2) a storm stripped beach sediment from three sites exposing the substrate, which was then surveyed and compared with radar profiles; (3) excavations in a previous study at nine sites were used to combine the stratigraphy with the radar images. GPR proved highly effective in this environment, revealing thin beaches in the south of the study area that thicken northward in the direction of alongshore sediment transport. Cliff height decreases northward such that there is a transition from beaches in front of cliffs, to beaches that overtop low cliffs, to barriers in front of a coastal lagoon.

This paper reports on a remote sensing station specifically designed to investigate eolian processes at a beach–dune system. The monitoring station is located at Greenwich Dunes, Prince Edward Island National Park, Prince Edward Island (Canada), and it is the second, improved generation of a previous system using continuous video and photographs. The setup consists of three digital single-lens reflex cameras, a two-dimensional sonic anemometer, two safires, erosion–deposition pins, and an array of batteries and solar panels. The cameras run on a timer that takes pictures every hour. The images are rectified and analyzed using a combination of ArcMap 9.2 and PCI Geomatica software, which permits the generation of moisture maps, vegetation, ice and snow cover, shoreline position, and erosion–deposition processes. The two-dimensional sonic provides continuous wind speed and direction, and the saltation probes record the intensity of transport events. The result is a large geodatabase of a time series of factors affecting eolian processes at the beach at a variety of temporal and spatial scales. This geodatabase can be queried, and it is a valuable tool for studying the frequency and magnitude of events delivering sediment from the beach to the dune and thus for improving our knowledge of sediment transport at coastal areas. Although the remote sensing station was initially conceived as a tool to measure subaerial processes, a full year of measurements shows large potential for the system to provide information on processes at the nearshore environment and ice dynamics.

The synergistic application of optical and radar satellite imagery improves emergency response and advance coastal monitoring from the realm of “opportunistic” to that of “strategic.” As illustrated by the Hurricane Ike example, synthetic aperture radar imaging capabilities are clearly applicable for emergency response operations, but they are also relevant to emergency environmental management. Integrated with optical monitoring, the nearly real-time availability of synthetic aperture radar provides superior consistency in status and trends monitoring and enhanced information concerning causal forces of change that are critical to coastal resource sustainability, including flooding extent, depth, and frequency.