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Finkl, C.W. and Makowski, C., 2021. Alongshore classification and morphometric analysis of coastal belts: The state of Oregon, USA. Journal of Coastal Research, 37(2), 238–271. Coconut Creek (Florida), ISSN 0749-0208.Classification of the state of Oregon coastal belt (western United States) was based on the interpretation of satellite imagery using the Biophysical Cross-shore Classification System (BCCS). This seven-county, 480-km stretch was subdivided based on coastal archetypes that formed distinct bio-geomorphological and ecological sequences on both alongshore and cross-shore axes. Shore-parallel and shore-perpendicular units were concomitantly determined by cognitive inspection of satellite images, in which cross-shore archetypical sequences were observed in the first instance to have alongshore spread that could be secondarily codified in terms of alongshore catenas. Because shore-normal transects encompass marine, coastal, and terrestrial environments that have a shore-parallel width, it was possible to extrapolate cross-shore classificatory units into alongshore stretches called domains. Characterization of alongshore domains was based on conjoining archetypes into catenary sequences that typify coastal belts both alongshore and cross-shore from adjacent offshore areas to several kilometers inland. Compilation of coastal belt catenas showed that promontories and headlands, which are composed of resistant igneous and metamorphic rocks, function as anchor points along the shore and are interspersed by sedimentary (littoral) coastal belts that contain mainland and barrier beaches backed by dune, wetland, flat (estuaries), or upland archetypes. A consizement of several alongshore domain catenary sequences within a particular coastal segment thus formed an overarching super domain. Typical alongshore super domains consisted of the following sequences: Barrier-Beach-Dune (Ba-Be-Du), Barrier-Beach-Dune-Wetland (Ba-Be-Du-W), Beach-Dune-Upland (Be-Du-U), Beach-Dune-Wetland (Be-Du-W), Beach-Cliff-Upland (Be-Cl-U), Beach-Wetland-Flat (Be-W-F), and Rock-Cliff-Upland (R-Cl-U). Morphometric analysis of each county allowed the determination of specific characteristics for each super domain (e.g., alongshore length, percentage of the county coastal belt, and percentage of the Oregon coastal belt). Furthermore, archetype morphometrics were calculated to show which cross-shore archetypical features were most prevalent along the state's coastal belt. This examination of the Oregon coast showed that the alongshore classification of coastal belts on a regional scale, which is based on cross-shore biophysical interpretations, offers the opportunity to characterize offshore, inshore, and onshore eco-geomorphological features through the use of super domains and morphometric analysis. This approach to coastal classification thus serves as a blueprint for the comprehensive characterization of coastal belts worldwide.

Finkl, C.W. and Makowski, C., 2021. Alongshore classification and super domain delineation of coastal belts based on interpretation of biophysical catenary sequences observed from satellite images. Journal of Coastal Research, 37(1), 1–25. Coconut Creek (Florida), ISSN 0749-0208.The cross-shore classification of coastal belts, facilitated by the interpretation of biophysical features from satellite imagery, is an adjunctory approach to traditional alongshore classification procedures. Methods such as the Biophysical Cross-shore Classification System (BCCS) (Finkl and Makowski, 2020a) and the Coastal Belt Linked Classification (CBLC) (Finkl and Makowski, 2020d) not only provide insight into cross-shore natural ecological variability and zonation, but also emphasize eco-geomorphological linkages so that shore-normal transitions and successions can be delineated and understood. The discernment of numerous cross-shore biophysical transect codifications in a satellite image seascape scene (referred to as either BCCS or CBLC code sequences) results in coastal belt segmenting that identifies offshore, nearshore, inshore, and onshore similarities and differences. This, in turn, can be correlated alongshore by establishing the swath widths of each cross-shore transect as an individual domain. Data integration and interpretation processes are similarly applied as procedural management of geological borehole (well) logs to determine drilling and petrophysical parameters. This study demonstrates that once all individual alongshore domains are interpreted for a specific coastal area, they can be collectively amalgamated and concised to create a universal alongshore super domain for the entire coastal belt. The advantage of constructing a Concised Alongshore Super Domain is that the procedure provides a sagacious and rational basis for swath alongshore classification of coastal belts. This study shows the effective use of this methodology across coastal belts of varying latitudes, as the interpolation of shore-normal ecological sequences validates the cross-shore correlation between transects and can result in a universal alongshore classification process in the form of super domains for coastal belts worldwide.

Finkl, C.W. and Vollmer, H.M., 2017. Methods for investigating sediment flux under high-energy conditions on the southeast Florida continental shelf using Laser Airborne Depth Sounding (LADS) in a Geographic Information System (GIS) dataframe. Laser Airborne Depth Sounding (LADS) bathymetric surveys conducted in 2001 and 2008 bracket two hurricane landfalls (Hurricane Ivan in 2004 and Hurricane Katrina in 2005) in Broward County, southeast Florida, thus providing an opportunity to investigate changes in bottom topography as a result of wave and current action. The seafloor in this region is characterized by a wide range of sedimentary features that are normally stabilized (held in place) by outcrops of carbonate bedrock and coral reefs. During high-energy events, however, the sedimentary deposits are partially mobilized by waves and currents. This methodological study used the two LADS bathymetric surveys to construct triangulated irregular networks (TINs, which are a digital means of representin...

Finkl, C.W. and Makowski, C., 2020. Coastal Belt Linked Classification (CBLC): A system for characterizing the interface between land and sea based on large marine ecosystems, coastal ecological sequences, and terrestrial ecoregions. Journal of Coastal Research, 36(4), 677–693. Coconut Creek (Florida), ISSN 0749-0208.The Coastal Belt Linked Classification (CBLC) is a novel approach based on interpretation of satellite images and assimilation of collateral data to characterize coastal belt segments that function as discrete interfaces between land and sea. This method is based on the formulation of concepts derived from the Biophysical Cross-shore Classification System (BCCS), the worldwide and regional-scale Large Marine Ecosystems (LME) classification, and the global distribution of terrestrial Ecoregions (ER). The coastal belt, a zone that extends across the shore from marine environments to inland terrestrial habitats, has recently been described in terms of cross-shore catenary sequences based on biophysical attributes of geomorphology and ecology. The CBLC formulates a cross-shore coastal classification by conjoining the Dominant Catenary Sequences (DCS) and Coastal Ecological Sequences (CES) with marine (LME) and terrestrial (ER) ecological systems; thus, a linkage is now provided between marine and terrestrial areas across coastal belts that function as transitional succession zones. This study proposes to combine the traditionally separated tripartite marine, coastal, and terrestrial delineations by melding them into a single descriptive code sequence that can be ascertained from interpretation of Google Earth satellite imagery and accessing collateral data via interactive LME and ER online platforms. Development of the CBLC is facilitated by the fact that LME and ER units are codified by numerals that are easily added to the formulated CES as prefixes and suffixes. The resulting combined alphanumeric code brings together a trove of information at different levels of investigation (Levels I – IV) that was heretofore not easily assimilated. This linkage of DCS and CES catenas with marine LME and terrestrial ER units brings added advantage to the interpretation of satellite imagery of the world's coasts, as it allows coastal belts to be viewed within the context of transitional interfaces between connected marine and terrestrial parameters. Recognition of coastal belts as interfacial bridges linking terrestrial and marine ecosystems into one codified descriptor sequence allows for cross-shore transects to be defined in the form of the Coastal Belt Linked Classification (CBLC) and provides an opportunity to fully comprehend the dynamic nature of coastal zones around the world.

Rodriguez Paneque, R. and Finkl, C.W., 2020. Erosion of carbonate beaches on the northeastern coast of Cuba. Journal of Coastal Research, 36(2), 339–352. Coconut Creek (Florida), ISSN 0749-0208.Beaches on the northeastern coast of Cuba have made this area one of the most important tourist destinations in the Caribbean, despite the fact that many beaches are visibly eroded. In this study, the causes and magnitude of coastal erosion on the northeastern coast of Cuba were evaluated using the Digital Shoreline Analysis System (DSAS 4.3) application, satellite images, and beach profiles. Time frames between 7 and 14 years were considered from 2003 to 2017 using satellite images and between 11 and 18 years using beach profiles. Results of this investigation showed that 56% of northeastern coast beaches tend to erode at a rate of less than 1.2 m/y. An increase in the recurrence of extreme events (hurricanes and tropical storms) during the last 39 years induced more beach erosion. It was furthermore observed that El Nino–Southern Oscillation events enhanced the sedimentary balance of the beaches by returning sand volumes that were transported in a westerly direction to their original shoreline locations. Possibly due to sea-level rise, which may be occurring in response to global warming, beaches on the northeast coast will retreat on average about 0.17 m/y. At this rate of shoreline recession, by the end of the twenty-first century, 14% of the beaches on this littoral will be lost, and the width of 27% of the other beaches will be significantly reduced.

Finkl, C.W. and Makowski, C., 2020. Lateral extrapolation of coastal catenary sequences using the Biophysical Cross-shore Classification System (BCCS) to create shore-parallel situational zonation mapping units. Journal of Coastal Research, 36(3), 457–471. Coconut Creek (Florida), ISSN 0749-0208.The Biophysical Cross-shore Classification System (BCCS), which uses transects to assess shore-normal ecological and geomorphological successions from offshore to onshore within a coastal belt (Finkl and Makowski, 2020a), also provides a basis for extrapolating cross-shore catenas into shore-parallel units. This paper shows that three-dimensional transects can be parameterized in terms of alongshore breadth as well as cross-shore width and depth below or elevation above sea level. The codification of cross-shore environments and habitats in the framework of the BCCS provides an interpretative basis for determining the lateral extent of transect units (archetypes and sub archetypes) by lateral extrapolation to polygonal mapping units. The method discussed here is akin to geological cores or cross-sections that are used to laterally extrapolate units within vertical sequences. Repetitive successions of archetypes, based on cross-shore ecological interpretation of satellite imagery, results in a common master sequence referred to as a Dominant Catenary Sequence (DCS). The DCS is composed of generic archetypes, such as Barrier, Beach, Beach Ridge, Cliff, Coral Reef, Delta, Dune, Flat, Ice, Lagoon, Mountain, Rock, Till (Glacial Material), Upland, and Wetland. The more detailed Coastal Ecological Sequence (CES) of a coastal belt, which is defined by a discrete codification sequence built up from the DCS, is formulated by cognitive geovisual analytics to link the dominant catena with a numbered shore-parallel shape distinction and subscripted sub archetypes to refine the sequential composite archetypes in a DCS. Once the DCS- or CES-labeled transect has been plotted on a satellite image, the identified shore-normal units can be extrapolated into shore-parallel polygons by traditional (i.e. visual, cognitive) image interpretive and mapping techniques to show the spatial extent of classified archetypes and sub archetypes.

Vollmer, H.M.; Finkl, C.W., and Makowski, C., 2015. Novel method for interpreting submarine geomorphology from LADS bathymetry using Surfer® 12 shaded relief maps. Laser Airborne Depth Sounding (LADS) produces high-resolution x, y, z surface data of seafloor topography that permits interpretation of geomorphological features, benthic environments, and habitats, as well as recognition of cultural features and submarine engineering structures. Because the quality of the resulting surface data depends on the type of processing software, it is worthwhile to consider potential improvements of previous bathymetric imagery displays generated from LADS data. A novel method for formatting, gridding, and exporting LADS data into Surfer® 12 software is shown to produce enhanced quality surfaces that facilitate shaded relief map analysis. This new Surfer 12 shaded relief map creation procedure intensifies the interpretation of submarine geomorphology from LADS bathymetry images in a GIS platform environment.

Makowski, C.; Finkl, C.W., and Vollmer, H.M., 2015. Geospatially integrated seafloor classification scheme (G-ISCS): A new method for cognitively interpreting benthic biogeomorphological f...

Finkl, C.W. and Makowski, C., 2020. Latitudinal and situational zonation of coastal catenary sequences observed from satellite images using the Biophysical Cross-shore Classification Syste...

Badescu, V.; Ciocanea, A.; Cathcart, R.B., and Finkl, C.W., 2013. Desalination brine disposal by submerged pipes in Red Sea. Journal of Coastal Research, 29(6A), 81–92. Coconut Creek (Florida), ISSN 0749-0208. Seawater desalination plants, especially those in Saudi Arabia, require the disposal of useless posttreatment brine— generally about 50% of the volume of seawater processed by such plants designed to make freshwater. This article focuses on the sustainability of the brine disposal process. A proper decision about the brine disposal method must take into account technical, environmental, and economic constraints. Brine disposal by submerged pipes is considered here; the case of desalination plants in Saudi Arabia on the Red Sea shore is considered as an example. The central concept is the available head at the discharge point. Higher values of the available head ensure larger jet dispersion lengths and better conditions for submarine brine dilution. We assessed the quality of the dilution process by calculating the Froude number of the brine discharge jet, whose optimum values are between 20 to 25. Using the Froude number allows us to find the optimum pipe length and the optimum depth of the discharge point for a sustainable brine disposal. Comments concerning the cost of the submerged pipes are presented.

Oretga, L.; Celentano, E.; Finkl, C., and Defeo, O., 2013. Effects of climate variability on the morphodynamics of Uruguayan sandy beaches. Effects of long-term trends in climatic variability on the morphodynamics of a reflective and a dissipative sandy beach in Uruguay (SW Atlantic Ocean) were analyzed. The Atlantic Multidecadal Oscillation (AMO) alternates between warm and cold cycles with a periodicity of roughly 70 years, with a shift toward a warm phase since 1995, resulting in an increase of sea surface temperature in the study area. Wind speed anomalies (WSA) also increased through time and were associated with an increasing speed of southerly winds, particularly after 1997. Beach morphodynamics showed no statistically significant trends in grain size, but long-term morphodynamic patterns differed between beaches: the dissipative beach showed an increase in swash and beach width, Dean's parameter, and the Beach Index (a measure of beach morphodynamic state). At the same time, the slope dec...

Benedet, L.; Finkl, C.W., and Dobrochinski, J.P.H., 2013. Optimization of nearshore dredge pit design to reduce impacts on adjacent beaches. The magnitude of the effects of nearshore dredge pits on adjacent beaches depends on a range of parameters, including seabed geomorphology, local wave climate, sediment supply, and pit design characteristics (e.g. distance offshore, depth of cut, cross-shore and alongshore extents, shape of pit). Delft3D, a morphological model developed by Deltares, was used to investigate relationships between dredge pit design parameters and impacts on adjacent beaches. The purpose of this study was to identify design parameters that affected the magnitude of dredge pit effects on adjacent beaches. An ancillary purpose was to develop a scientific basis for dredge pit design recommendations for beach restoration and other sediment needs of coastal infrastructure projects. Dredge pit design sensitivity tests were conducted using Delft3D. A schematic model was constructed usi...

Over the last century, remotely sensed mapping of continental shelf seafloor topography has had a rich history of applied research with varying techniques, all of which strive to accurately visualize the submarine benthos. Many early techniques (e.g., three-dimensional hachure maps) relied solely on the researcher’s knowledge and cartographic skills in absence of technological advances yet to be made. Acoustic mapping practices were then derived from war-time sonar sweeps that painted a surprisingly vivid picture of the seafloor through the use of sound. Through time, more sophisticated acoustic remote sensing techniques were developed and used as either sidescan sonar, single beam echo sounders, or multibeam reflection sounders. More powerful ground-penetrating seismic techniques have also been used to not only map the surface layer of the seafloor, but to also visualize what lies below the benthic interface. However, aircraft and satellite-assisted techniques enabled researchers to recently make considerable advancements in the visualization of benthic environments. Once mainly used as military reconnaissance procedures for strategic planning, the advent of high-resolution aerial photography and orthoimagery has proven to be among the most effective techniques for visualizing shallow, low turbid waters along continental shelves. Equally as effective for clear waters within the nearshore of the continental margin are airborne laser bathymetry (ALB) methods, which use pulses of light to acquire bathymetric and topographic configurations based on airborne laser reflectance. Lastly, hyperspectral and multispectral sensors onboard orbiting satellites (e.g., IKONOS, Landsat, MODIS, SPOT) provide a continuous stream of benthic environment visualization without the logistical inconveniences of deploying a vessel or aircraft every time images are to be acquired. A historical review of advances in seafloor mapping methods shows that remote sensing techniques led to new ways of visualizing dynamic benthic environments that ranged from broadly generalized geomorphological features to specific biological coverages.

Australia is one of the driest continents on earth with most interior lands classified as steppe or desert. With an expanding coastal population pushing farther inland, the need for freshwater increases for urban use, agriculture, and industry and because there is little freshwater at the surface and most of the groundwater is too saline and generally unsuitable for multiple uses, new sources of freshwater must be sought to sustain future development of Western Australia's interior. To mitigate this ongoing macroproblem, it is proposed to establish a new Southern Ocean maritime sea-lane between Antarctica and Western Australia with the first large-scale deployment of very capacious floating liquid freshwater containers (Stauber bags), barges hauled and shuttled regularly by carousel-type supertugboats to convey a directly acquired, essentially cost-free, bulk-harvested potable subglacial Antarctic meltwater possibly siphoned from beneath the floating Amery Ice Shelf and transported to Western Aus...

It might be argued that this paper does not sensu stricto contribute to "polar science." It, however, rekindles aspects of its history and of that of both oceanography and cartography. Obviously the interest for the polar regions was keen in the 19th century and elicited financial support. The paper may lift anew the veil that has somewhat dimmed the light that should shine on polar science achievements of Belgian explorers and scientists. Knowledge of the names of geographic features in the Antarctic is probably less widespread, and yet, there are many Belgian names on and near the southernmost continent. Most names were given by the head of the first-ever Antarctic expedition to spend a winter on the southernmost continent. Belgian Royal Navy Lieutenant Adrien de Gerlache de Gomery's expedition in the Antarctic brought back a wealth of scientific information. His trip ended precisely 111 years ago, and has been--literally--carved in stone as the Belgica is indeed one of the 20 oceanographic vessels Prince Albert I of Monaco selected to be represented on the façade of the Musée Océanographique de Monaco.

Coastal restoration in Louisiana requires clean sands for beach and dune restoration, whereas mixed sediments are required to rebuild marshes. The Louisiana coastal erosion problem is especially dire because it occurs on several fronts with the narrowing and overtopping of barrier islands and loss of back barrier bay and interior marshlands. Coastal restoration efforts in Louisiana depend on emplacement of sediment to build up barrier island and deltaic systems. Discovery of usable sediment is thus a vital factor in restoration efforts because up to 80% of some restoration project budgets can be allocated to exploration, exploitation, and emplacement of sediment. Because this cost is directly proportional to the distance of borrow sources from the project area, the cost-effectiveness of barrier island restoration and marsh creation depends on locating sufficient sediment volumes that are suitable for placement on beaches and dunes and for creating marshes. The restoration of Louisiana's barrier i...

Continental shelf environments along the Florida Atlantic southeast coast offshore Palm Beach County were mapped by interpreting seafloor topography derived from airborne laser bathymetry. The study area covered approximately 270 km2 along 75 km of coast, extending from the shore to about 55 m water depth beyond the shelf break to the upper Florida-Hatteras Slope. Forty-two mapping units were used to depict seafloor features that ranged from bedrock outcrops and coral reefs to different types of morphosedimentary bodies. Background theory and protocols of geomorphological symbolization are provided as a rationale for the seafloor mapping. Geomorphological mapping symbols were developed specifically for this project and collected in a symbol library as part of an ArcInfo GIS extension that was used to produce the maps in a GIS environment. Spatial distribution patterns of landform assemblages evident in the color-pattern mapping units permitted regionalization of shelf environments into three prim...

Differentiation of continental shelf morphology along the southeast Florida Atlantic coast was based on interpretation of airborne laser bathymetry. The 600-km2 shelf study area, which had a shoreline extent of about 160 km and extended up to 10 km offshore, displayed a diverse range of seafloor morphologies that were characteristic of four main alongshore reaches. Reach I (sand flats and karst topography) in the northern part of the study area is terminated southward by the Bahamas Fracture Zone, a major morphotectonic feature. Reach II (sand flats and coral reefs) is characterized by sand flats with diabathic channel fields leeward or shoreward of the Florida Reef Tract, the seaward margin of which occurs along the shelf break on the upper part of the continental slope. Reach III (sand flats, hardgrounds, and coral reefs) is characterized by extensive nearshore rock outcrops that are exposed as bare rock surfaces on the seafloor or are variously mantled by thin veneers of sand that are not thic...

Beach erosion, a problem along most sandy shores, can be caused by man-induced interventions to the coast or natural processes. Remediation of beach erosion (i.e., beach restoration) along eroding developed beachfronts is commonly practiced in the United States by periodic beach renourishment with or without coastal structures. Rates of erosion within beach fills generally vary greatly, and areas that erode faster than the nourishment average are commonly termed erosional hot spots (EHSs). Delray Beach, located on the southeast coast of Florida, was renourished for the fourth time on December of 1992 with about 914,000 m3 of sand dredged from offshore and placed along 2.7 km of beach. About 448,000 m3 of the fill had eroded away by 2001, about eight and a half years after initial construction. Two beach segments with erosion rates higher than the nourishment average were identified based on analysis of annual beach profile data. About 40% of the eroded volume accrued from one of these beach segme...

Beach nourishment requires large volumes of sand from offshore and new sources are constantly sought for development. The sediment-starved continental shelf off the central-west coast of Florida has traditionally supplied beach-quality sediments from ebb-tidal shoals and nearshore sand sheets, but as these supplies dwindle, sand searches increasingly look farther offshore for resources. Widely spaced sediment ridges, interspersed by karstified limestone seafloor (hard grounds), offer potential as sand resources that can be exploited by dredging to renourish eroded beaches for shore protection. The sand ridges, late Holocene in age, are generally shoreface detached, sediment starved, and clustered in “ridge fields.” Six sediment ridge fields identified along 285 km of coast (Anclote, Sand Key, Sarasota, Manasota, Captiva, and Collier) contain about 1.4 billion cubic meters of sediments that are potentially available for dredging. Evaluation of these sediment sources, within the purview of the USMi...

Coastal land loss in the Mississippi River delta region, related to degradation of wetlands and erosion of barrier islands, contributes to loss of valuable habitat, endangerment of infrastructure and socioeconomic systems, and coastal flooding hazards. Restoration of these ecosystems is thus a primary activity that requires large volumes of sand to rebuild beach–dune systems and restore wetland habitats. Sand sources have traditionally been sought offshore in the marine environment, but there are problems associated with setbacks from oil and gas infrastructure, presence of muddy overburden, and limited reserves of beach-quality sediments. Fluvial sand sources in channel and point-bar deposits become an attractive alternative for barrier island restoration because of large volumes of relict deposits and because active sand waves are renewable. Results of preliminary geophysical and geotechnical investigations in the lower Mississippi River (south of New Orleans) along a 32-km stretch of the river...

Airborne laser bathymetry (ALB) is a new laser bathymetric survey tool that has applicability in clear coastal (Case II) waters to depths of −70 m. The new sounding technique features rapid acquisition of large, high-quality data sets via variable swath widths that are independent of water depth. This advanced ALB system was deployed along the continental shelf of southeast Florida (Palm Beach, Broward, and Miami-Dade Counties), providing a contiguous data set for 160 km of coast from onshore to 6 km offshore. Image enhancement of the ALB digital data facilitates recognition of numerous seafloor features and bathymetric patterns. Bathymetric analysis of the 600-km2 survey area on the continental shelf shows inherited lithologic features that are partly covered by surficial sediments. Primary parabathic (shore-parallel) provinces include: (1) nearshore rocky zones dominated by the Anastasia Formation, (2) coral-algal reef systems (Florida Reef Tract [FRT]), and (3) marine platforms (terraces). Sed...

Airborne laser bathymetric (ALB) systems rapidly acquire large, high-quality datasets via variable swath widths that are independent of water depth. Laser bathymetric survey tools have applicability in clear coastal (Case II) waters down to −70 meters depth. Deployed along the southeast Florida (Palm Beach, Broward, and Miami-Dade Counties) coast, an advanced ALB system provided a continuous dataset for 160 kilometers of coast from onshore to 6 kilometers offshore. Digital terrain models developed from this high-density bathymetric data permitted recognition of numerous seafloor features and bathymetric patterns from different image formats. Bathymetric analysis of the 600-km2 survey area on the narrow continental shelf shows inherited lithologic features that are partly covered by surficial sediments. Primary parabathic provinces include: (1) nearshore rocky zones dominated by the Anastasia Formation, (2) coral-algal reef systems (Florida Reef Tract [FRT]), and (3) marine terraces. Secondary sed...

Studies of coastal morphodynamics are becoming increasingly more focused on quantification of relationships between processes, form and function of dynamic landform systems because wave climates (e.g., wave height, wave period, seasonality, cyclical patterns) and sediments (i.e., composition, size, and shape) interact in various ways to collectively produce distinctive types of beaches. This paper identifies criteria and boundary conditions that characterize beaches in terms of morphodynamic states (environmental conditions or energetic stages of development) that produce discrete beach types. Long-term hindcast wave statistics (U.S. Army Corps of Engineers, Wave Information Study), small-scale aerial photography, cross-shore beach profiles, and beach sediment data from Florida's Atlantic (Delray Beach) and Gulf (Longboat Key) coasts were used as a basis for linking beach morphology with coastal processes. The role of cross-shore sediment variation in classification of beaches is related to prediction of beach types using the dimensionless fall velocity (Ω), the results of which are compared with field observations and morphological interpretation of aerial photographs. A new curve-fitted equation, the morphodynamic boundary condition (MBC), identifies parametric limits that force dissipative or reflective beach conditions when new sediments are artificially placed on the beach (e.g., during beach nourishment programs). Results indicate that the Ω parameter of the new model is strongly influenced by cross-shore selective sorting of bimodal sediments, temporal changes in beach grain size, seasonal wave patterns, and inputs of new sediments to the littoral system. Calculation of Ω using beachface samples produces a bias toward reflective states (decrease in Ω). Sediment samples from bar systems, on the other hand, produce a bias toward dissipative states (increase in Ω). Composite grain size of the active profile is recommended because it more accurately predicts beach states based on Ω (compared to field observation of beach type). The addition of new sediment to beaches requires an understanding of form–process continuums and the MBC equation is a step in that direction. The potential impacts of beach nourishment on beach morphology can be thus determined from local wave data by calculating hypothetical Ω values as a function of changes in beach composite grain size and a constant K value. The MBC equation (Ω=Kdf−2), as applied in planning phases of renourishment projects, can predict changes in beach morphodynamic states, as conditioned by the grain size of the placed fill.

The decrease in longshore sediment volumes from north to south, calculated for littoral cells between inlets, indicates significant loss from the littoral drift system along the Florida east coast or localized deposition. The decrease in littoral drift volume from about 490,000 m3 of sediment over a distance of about 550 km (average diminution rate of about 890 m3 km−1) was traditionally accounted for in terms of alongshore deposition and some unknown degree of speculated offshore transport. With the application of laser airborne depth sounding (LADS) technology to bathymetric survey in southeast Florida (2001–2003), recognition of detailed bottom topography became possible for the first time. Significant in this regard was the bathymetric display of macro- and mesoscale morphological features that showed areal continuity of sandy bottoms and the prominent but disjunctive occurrence of relict barrier coral reef tracts that line the shelf edge. Identification of gaps in the line of barrier reefs s...

Chronic erosion of beaches along the eastern Texas barrier island coast is increasingly mitigated by renourishment efforts that periodically place large volumes of sand onshore. Location of beach-quality sands on the inner continental shelf is challenged in an environment where terrestrial rivers deposit fluvial sediments in back bays and lagoons instead of offshore and by shelf areas that are dominated by muds. The search for beach-quality sands thus requires understanding of the coastal geological framework and morphodynamic processes that accompanied late Quaternary evolution in the northern Gulf of Mexico. The occurrence of surficial sand deposits as positive bathymetric features on the seafloor (ridges, shoals, banks) and presence of sands buried in paleovalley (drowned channels) infill sequences makes for complicated search procedures that must accurately differentiate a range of sedimentary settings by geophysical and geotechnical surveys. Compilation of vast amounts of data from historica...

Many different kinds of classification have been applied to coasts in attempts to characterize dominant features in terms of physical or biological properties, modes of evolution, or geographic occurrence. Some of the earlier general classifications were broad in scope but lacked specificity while other specialized systems were narrowly focused, providing uneven coverage of taxonomic units for coastlines of the world. Due to more comprehensive study of coasts and the increasing availability of information, especially digital formats in GIS frameworks, integrated and systematic approaches to coastal classification are favored. The complex demands of today require sophisticated solutions to overlapping and interrelated problems in the littoral, as facilitated by organization of biophysical parameters into a coherent whole or universal scheme. The developmental approach to a new comprehensive classification system is thus proposed for the coastal fringe, a swath zone 5 to 10 km wide across the shore...

Erosion of sandy beaches is a worldwide problem that elicits innovative geoengineer‐ing techniques to reduce adverse impacts of shoreline retreat. Beach replenishment has emerged as the “soft”; shore‐stabilization technique of choice for mitigating beach erosion. This method of shore protection involves the addition of sand to the littoral sediment budget for sacrificial purposes. Because inland sand sources are often uneconomical or impractical to use, and known nearshore sources are limited, finding adequate quantities of suitable sand on the inner continental shelf is often vital to beach replenishment projects. The technical studies of survey and materials analysis that identify and delineate usable sand sources are sometimes almost as expensive as small‐project dredging, pumping, and placing the sand on the beach as fill. Inadequate quantity or substandard quality of shelf sand, as well as often‐prohibitive overhead expenses, thus compel shoreline managers to seek suitable sand sources offshore. In t...

Makowski, C.; Finkl, C.W., and Vollmer, H.M., 2016. Classification of continental shelves in terms of geospatially integrated physiographic realms and morphodynamic zones. The continental shelf off southeast Florida contains a range of benthic environments that are discernible via remote sensing platforms because of low turbidity in the water column. Using the Geospatially Integrated Seafloor Classification Scheme (G-ISCS), physiographic realms and associated morphodynamic zones were cognitively interpreted and classified at a nominal scale of 1:6000 across four remote sensing platforms (i.e. GeoEye IKONOS-2, Landsat-5 Thematic Mapper [TM], Landsat-7 Enhanced Thematic Mapper [ETM], and National Agriculture Imagery Program [NAIP] high-resolution aerial orthoimagery). Attribute tables were created in conjunction with interpretations to quantify and compare spatial relationships between classificatory units and the different remote sensing platforms. Resultant maps exported from ESRI ArcGIS® ArcMap ...

Ebb-tidal deltas or ebb shoals in moderate to high-energy environments often contain well-washed sandy sediments. These clean sands attract the attention of coastal engineers because they are commonly suitable for shore protection efforts such as beach renourishment (replenishment), dune restoration, and marsh remediation. Ebb-tidal deltas are sediment sinks where sandy materials are sequestered in deposits that can build up to such significant proportions that they form large coastal salients. In addition to sediments debouching from the inlet, longshore sediments are either trapped in the shoal or are bypassed in swash bars. Accumulation of sediments in these depocenters at the mouths of inlets often appear as a ready-made point borrow source that can be accessed for shore protection by dredging and placement on adjacent eroded shores. Ebb-tidal deltas are, however, in delicate balance with inlets, longshore drift, beach-dune systems and overall coastal stability. Removal of sediment volume by dredging from deltas interrupts the sand-sharing balance between inlets, ebb-tidal shoals, coupled beach-dune systems, wetlands, and shoreline stability.