USGS St. Petersburg Science Seminar Series Archive
The SPCMSC hosts a monthly seminar featuring scientists from both U.S. Geological Survey and non-USGS scientists. Explore our archive of past seminars below.
Explore past seminars:
Tuesday, April 16
Simeon Yurek
USGS Wetlands Aquatic Research Center
"Evaluating Optimal Foraging of Wetland and Coastal Species Using Individual-Based Modeling and Structured Decision Making."
Abstract
Optimal foraging is a central problem in ecology and in fish and wildlife management. Foragers on patchy landscapes must efficiently balance time between searching for and consuming resources to meet their daily energetic needs, while also avoiding predators, and at times competing for resources with other foragers. Availability of foraging resources is often directly linked to hydrodynamic and geomorphic processes that determine the types and densities of prey and browse that landscapes can support. On landscapes that are highly degraded through climate change and human land use, forage resources may be critically scarce, diffuse, separated by great distances, and difficult to locate and detect. For these reasons, optimal foraging has been described as a decision problem with specified objectives, value systems, tradeoffs, consequences, constraints, and uncertainty. Importantly, while the forager faces the problem of locating sufficient forage resources, natural resource managers also face a decision problem of identifying restoration strategies that best support the species and ecosystems that they are managing. This talk discusses two approaches for examining the optimal decision problem. The first approach uses individual-based ecological modeling (IBM) to better understand how patch selection foraging behaviors of wading birds collectively determine outcomes for foraging and population dynamics. An example is given for the Everglades, where prey availability for wading birds is strongly determined by seasonally-dynamic inundation and drying of the patterned geomorphology of the wetland landscape, which results in dynamic conditions of habitat connectivity, and prey dispersal and concentration. The second approach applies structured decision-making (SDM) to co-produce restoration strategies with fish and wildlife managers to ensure that decisions align with specified management objectives. SDM follows the organized and deliberative PrOACT framework (Problem Statement, Objectives, Alternatives, Consequences, and Tradeoffs), which specifies components of the decision-making problem using supporting tools such as objectives hierarchy tables, SMART tables (Simple, Multi-Attribute Rating Technique), and risk analyses. These techniques help managers to quantify the impact of hazards on natural resources of concern, and to illuminate tradeoffs in their decision making. An example is given for barrier islands in the northern Gulf of Mexico, where successional dynamics of beach, dune, scrub-shrub, and maritime forest strongly determine prey availability for imperiled shorebird and beach mice populations. Both of these approaches are developed to support management decision making given uncertainty in climate change and land use practices.
April 2, 2024
Drs. Hongqing Wang and Qin Jim Chen
Dr. Hongqing Wang, USGS Wetland and Aquatic Research Center; and Qin Jim Chen, Northeastern University, Civil and Environmental Engineering & Marine and Environmental Sciences
“Monitoring and Modeling of Wave Dynamics to Assess the Effectiveness of Living Shorelines”
Abstract
Living shoreline techniques have been applied globally in replacement of hardened structures for coastal protection and restoration and ultimately for the development of sustainable shorelines under climate change and sea level rise. Wave energy is one of the major driving forces for shoreline degradation, erosion, and retreat. Therefore, wave attenuation capacity of living shorelines as well as structure-induced changes in current velocity and sediment transport, deposition, and erosion associated with wave dynamics need to be determined to assess the effectiveness of the living shoreline projects. The success of living shoreline projects requires the integration of monitoring and modeling to obtain long-term data on wave, current, and sediment dynamics with and without living shoreline structures. Here, we present the integrated monitoring and modeling of nearshore processes at three living shorelines along the Atlantic coast. This project is supported by the NFWF Hurricane Sandy Coastal Resiliency Competitive Grant Program. We focus on the application of modeling in support of the assessment of long-term wave attenuation capacity of living shorelines using Fog Point living shoreline in Chesapeake Bay as an example. We present a novel framework leveraging scientific machine learning methods for accurate and rapid prediction of long-term hydrodynamic forcing impacting living shorelines using short-term measurements of water levels and wind waves. Long Short-Term Memory (LSTM) models were developed using four-month wave measurements in the stormy seasons to predict integral wave parameters and energy spectra for multiple years. The validated models were then used to determine the long-term wave forcing impacting the living shorelines based on the modeled wave characteristics and spectra. Model results show that the surrogate models utilizing LSTM to predict wave spectra in the frequency domain enable long-term predictions of spectral wave evolution with a minimal computational cost. Our findings provide valuable insights into the efficacy of living shorelines in attenuating wave energy.
February 26, 2024
Tony L. Diaz
Ph.D. student, University of Florida
"The “Bathy-drone” for Underwater Survey and Mapping"
Abstract
A unique drone-based system for underwater mapping (bathymetry) was developed at the University of Florida. The system, called the “Bathy-drone”, is comprised of a drone that drags, via a tether, a small vessel on the water surface in a raster pattern. The vessel is equipped with a COTS sonar unit that has down scan, side-scan and chirp capabilities and logs data onboard. Data can then be retrieved, post mission, from the vessel and plotted in a variety of ways. The system provides both isobaths (underwater topo plots) and contours of bottom hardness. Extensive testing of the system was conducted on a 5-acre pond, located at the University of Florida Plant Science and Education Unit in Citra, FL. Prior to performing scans of the pond, ground truth data was acquired with a RTK GPS unit on a pole to precisely measure the location of the bottom at over 300 locations. An assessment of the accuracy and resolution of the system was measured by comparison to the ground truth data. During testing, our research group found that there are numerous advantages and attributes of the Bathy-drone system including ease of implementation and the ability to initiate surveys from the land without the need for a boat. The system is also inexpensive, light-weight, thus making transport convenient. The Bathy-drone can raster at speeds of between 0 and 12 mph, and thus can be used in waters with swift currents. Additionally, there are no propellers underwater, so the vessel does not have a tendency to snag on floating vegetation. We have been able to raster an area of more than 10 acres in one battery charge and in less than 25 minutes. Surveys for the SFWMD were conducted on the Kissimmee River and canals in the Lake Worth District.
January 16, 2024
Megan Gillen
Ph.D. Candidate in the MIT-WHOI Joint Program
"Modeling Lower Shoreface Equilibrium Morphology and Net Transport under Dynamic Wave Conditions."
Abstract
The lower shoreface, a transitional subaqueous region extending from the seaward limit of the surf zone to beyond the closure depth, serves as a sediment reservoir and pathway in sandy beach environments over annual to millennial time scales. Despite its important role in shoreline dynamics, however, the morphodynamics of the lower shoreface remain poorly quantified and understood. Previous shoreface energetics models often use static wave parameters, oversimplifying the variable wave climates experienced in these regions. These assumptions may be causing discrepancies between equation-based theoretical equilibrium profiles and bathymetric data. We combine energetics-based sediment transport formulae with empirical wave climate data to incorporate dynamic wave conditions in modeled equilibrium profiles and net transport rates. We also examine using bedload formulae, neglected in prior approaches, with suspended transport equations to model sediment flux and morphology. Equilibrium shoreface shape computed using a 40-year wave climate is steeper in shallower water compared to profiles using single wave characteristics. High energy waves direct sediment onshore at equilibrium, while short-period waves move sediment offshore. Most waves moving sediment at steady-state also deviate from equilibrium wave values, demonstrating the importance of utilizing long-term wave climates when modeling transport across the shoreface. Our results reveal how infrequent storm waves and bedload affect shoreface equilibrium morphology and net transport, informing our understanding of lower shoreface morphodynamics.
2023 Seminars
October 31, 2023
Dr. Marci Robinson
USGS Florence Bascom Geoscience Center, Reston, VA
"Middle Miocene shelf deposits from Maryland and Virginia and what they tell us about North Atlantic paleoceanography"
Abstract
Sedimentary records from the Maryland and Virginia Coastal Plain contain valuable quantitative paleoecological data from the Miocene Climatic Optimum (MCO) and the Middle Miocene Climate Transition (MMCT). These records occur as marine sedimentary packages deposited during intervals of high sea level, reflecting eccentricity-scale variability in glacio-eustatic sea level and confirming episodes of Antarctic ice sheet growth and decay. Each sedimentary package is unique in that it reflects the magnitude, speed and duration of sea level change and the resulting environmental conditions. Many of these records are contained within the iconic Calvert Cliffs in southern Maryland along the western shore of the Chesapeake Bay. Ongoing work aims to correlate the Calvert Cliffs outcrops with the Baltimore Gas & Electric (BG&E), Haynesville and Solomons Island cores to create a composite section of the most complete record of the MCO and MMCT in the Atlantic Coastal Plain. These records will be used to establish refined estimates of sedimentation rates and the duration of hiatuses. In this talk, I will focus on the process of building reconstructions of local and regional paleoceanography and productivity, to include changes in ocean circulation, bottom water oxygenation and upwelling strength. I will examine these data in terms of the climate framework established by age-diagnostic diatom and planktic foraminiferal species, alkenone stratigraphy, and orbital (eccentricity-scale) tuning. And I will show how the lateral correlation of sedimentary units between cores and outcrops in very close proximity is aided by cluster analyses of benthic foraminiferal assemblages. This research will yield a reconstruction of paleoenvironments through time and insight into how biologic communities are affected by the variable regional paleoceanography among different warm intervals of the MCO.
October 17, 2023
Dr. Joel Carr
USGS Eastern Ecological Science Center
"Model explorations of nonlinear dynamics, alternate ecosystems states and future projections in coastal seagrass (Zostera marina) systems"
Abstract
In many systems, feedbacks that exist between biota and their abiotic environment have the potential to lead to nonlinear dynamics. These feedbacks may involve changes in microclimate, fluid flow, sediment dynamics, biogenic soil formation, nutrient cycling and soil respiration among many others. These feedbacks and interactions are often further complicated by stochastic or cyclic processes such as fire, large storms, and/or seasonality. For example, intertidal coastal environments are prone to changes not only induced by sea level rise but by increases in storminess, temperature, and anthropogenic disturbances. It is often unclear how changes in external drivers may affect the dynamics of these low energy coastal environments because their ecogeomorphic response is non-linear, and characterized by many thresholds and discontinuities due to the presence of feedbacks. As such, process-based modeling of the ecogeomorphic processes underlying the dynamics of these ecosystems is useful, not only to predict their change through time, but also to generate new hypotheses and research questions. Many eelgrass models that incorporate impacts of temperature and light on photosynthesis and respiration have been developed; however, accounting for uncertainty in future projections of eelgrass is difficult due to large number of combinations of environmental drivers with different occurrence likelihoods. Here I will share a suite of modeling exercises exploring impacts of feedbacks for seagrass (Zostera marina) starting from a simple process-based point models, building through more spatially explicit formulations and eventually sharing a distribution driven model framework that leverages combinations of empirical and mechanistic relationships to allow for modeling and tracking the distribution of potential outcomes simultaneously.
October 11, 2023
Dr. Michael Kinsela
University of Newcastle, Australia, Coasts & Estuaries Research Group
"Mapping the coastal seabed to understand past and future coastal change in Australia"
Abstract
Why are some sandy coasts in southeastern Australia experiencing sustained erosion while others nearby are accreting? How sensitive or resilient are different coasts to present/future sea-level rise? How does the coastal seabed influence cross-shore sediment transport and sediment budgets along embayed coastlines? What is the offshore extent of the “active” beach system over coastal planning and management timescales? How can we predict coastal change in settings with complex geomorphology and variable sedimentology?
The coastal seabed holds clues for answering these questions, and many more. It stores records of past coastal evolution, information about coastal dynamics over event to geological timescales, and hints on how shorelines may evolve under projected sea-level rise.
Mike will discuss these questions using recent and ongoing research from the southeast Australian coast, a microtidal and wave-dominated setting with a strong north-south gradient in geomorphology and sediment availability.
August 15, 2023
Robert Fieglist
University of Georgia
“A Process Based Model for Forecasting Wave Runup Along the Coast of Georgia”:
Topic: X-Beach Wave Runup Modeling
Wave runup is an important nearshore process that impacts water levels, sediment transport, and coastal design. Current methods for forecasting wave runup implement an empirical model (Stockdon et al., 2006) which requires offshore wave height, wave period, and generalized beach slope. A new process-based methodology was created that implements site-specific cross-shore topo-bathy into the phase-resolving numerical model, XBeach non-hydrostatic (XBNH). Wave runup forecasts are generated from offshore wave conditions and a system of equations derived from simulation results at three different still water datums for each beach profile. Using forcings from Hurricanes Ian and Nicole (2022), the model predicts events of collision, overwash, and inundation for the coast of Georgia and suggests that wave runup is significantly impacted by the still water level and topo-bathy. Coupled with a field experiment that provides wave runup data using 12 pressure sensors and highly accurate RTK (Real-Time Kinematic positioning, < 2 cm vertical error), the results show that the pressure sensors effectively capture wave runup events and XBNH accurately models the total water level for the limited wave conditions throughout the experiment.
July 25, 2023
Stephan O'Brien
University of South Florida St. Petersburg
"Geomorphic study of Apollo Marine Park using Multibeam Bathymetry and Backscatter Data"
Abstract
Apollo Marine Park is located in southeast Australia at the western edge of Bass Strait and has a total area of 1184 km2 . The park supports ecologically diverse species of marine life, including fish, lobsters, octopus, and seals. Deakin Marine Mapping completed a study to establish a baseline geomorphic understanding of Apollo Marine Park. A Kongsberg EM2040C dual swath multibeam echo sounder collected bathymetric, water column and backscatter data at the site. A bathymetric surface was generated at a resolution of 2m, and a backscatter mosaic was processed at 1m resolution. High resolution hydrographic mapping of the park identified an extensive hard reef in the northwest and a paleoshoreline south of the hard reef. The reef also consisted of a hard bottom covered in sediment veneer. The western region of the park featured hard and consolidated sedimentary bedforms. Information from this research will assist in identifying hard and soft substrate habitat distributions at the park and locating deep-shelf reefs to aid the planning of biological sampling such as baited camera systems. Biological sampling studies can be utilized in the future to characterize benthic fauna and fish communities present in Apollo Marine Park.
June 29, 2023
Benjamin Tsai
“Coastal Hydrodynamics and its Interaction with Structure and Sediment.”
Abstract
The rise in sea levels and the increase in extreme weather events due to climate change have emerged as significant issues for society. It is imperative to account for their effects when designing coastal structures and formulating resource management strategies. Rapid coastal morphodynamic changes during storms, such as beach erosion and scouring around critical infrastructure like bridge piers, are of particular interest. To address these concerns, this study employs advanced computational fluid dynamics techniques within a multi-phase flow framework, with the aim of deepening our understanding of complex physical processes.
June 20, 2023
Ian Reeves
Woods Hole Oceanographic Institution
"Modeling Cross-Landscape Connectivity and Ecogeomorphic Couplings in Coastal Barrier Systems"
Abstract
Sediment exchange within and among the barriers, marshes and bays of coastal barrier systems is critical to the vertical and horizontal maintenance of these landforms and their resilience to the impacts of storm events. However, long-term (decadal to centurial) morphologic modeling of coastal barrier systems typically considers components of the coupled system in isolation or neglects important internal ecogeomorphic dynamics controlling these sediment pathways. In this talk, I present a series of modeling exercises that demonstrate how these cross-landscape couplings and the ecogeomorphic processes that influence them are essential components of long-term barrier system evolution. I first show that dune-storm interactions can lead to alternating periods of relative barrier stability and rapid transgression, controlling both the rate and style of retreat through the modulation of overwash flux. Next, I suggest that woody vegetation, by obstructing overwash flux across the barrier interior, promotes significantly narrower and less voluminous barrier morphology and increases vulnerability to drowning under certain forcing conditions. Then, in connecting components of the entire barrier system from the shoreface to mainland forest, I demonstrate that landward barrier migration can be a leading cause of back-barrier marsh loss, while periods of barrier stability can allow for recovery of back-barrier marsh extent.
June 6, 2023
Dawn Kotowicz
USGS St. Petersburg Coastal and Marine Science Center
"Social science? How social science can aid Coastal Change Hazards scientists"
Abstract
This talk will describe how social science can inform and support coastal change hazards scientists and science products. I will introduce myself and my background, including topics and methods that I bring to my work at USGS. I will provide an overview of four specific social science concepts that I propose the program could use to better connect their science with stakeholders, and include several examples where these ideas are being employed.
May 23, 2023
Rose Palermo
USGS St. Petersburg Coastal and Marine Science Center
"Barrier island stability and evolution in microtidal environments"
Abstract
In environments with large tidal ranges, inlets segment barrier chains over a length scale that depends upon a balance between tidal flows and alongshore sediment transport. However, segmented barriers are also found in regions with small tidal ranges. These barriers typically have a curved shoreline and are often hydrodynamically isolated from other barriers. The controls on and scales of barrier segmentation in the relative absence of tides are poorly constrained. It is likely that in microtidal environments, alongshore sediment transport and overwash may plan an outstanding role on the evolution of narrow and low-relief barriers. Here, I present a theoretical framework to estimate the alongshore length scales at which a barrier will either breach or heal following an alongshore disturbance in the barrier morphology. This theory applies a non-dimensional stability analysis that compares overwash (advective) and alongshore sediment transport (diffusive) processes along barrier island chains. I apply this framework to barrier islands in the microtidal Gulf of Mexico using the lengths, widths, heights, and estuary depths measured from remotely sensed geospatial and topobathymetric data. I’ll further evaluate modeled predictions of barrier stability and evolution under increasing rates of sea-level rise and the implications for coastal management.
April 25, 2023
Stefano Conti
University of New South Wales Sydney
"Laboratory Study of Dune Face Erosion Mechanisms Incorporating Variable Dune Porewater Moisture Content"
Abstract
Coastal sand dunes provide significant natural protection against coastal flooding. Understanding the physical drivers of dune erosion is therefore key to improve nature-based methods for coastal protection. This paper presents the results of controlled dune erosion experiments conducted in a wave flume, to examine the potential role of sand moisture content on dune erosion. Two moisture contents, representing a ‘dry’ and ‘wet’ dune (volumetric water content, VWC = 0.03-0.08 and VWC = 0.13-0.18, respectively) showed that dune pore-water content can influence the rate of dune erosion. The dune face consistently receded more rapidly for the higher moisture content cases. However, the final dune recession magnitude was observed to be independent of the initial sand moisture content and instead was a function of the vertical extent of wave runup relative to the dune face.
April 4, 2023
Mike Savarese
Florida Gulf Coast University
"Impact of Hurricane Ian on the Geomorphology of the Southwest Florida Coast"
Abstract
Hurricane Ian, making landfall in Southwest Florida on September 28, 2022, severely impacted the coastal geomorphology of the region’s barrier islands and attached beaches. Incoming storm surge, because of its extreme height, resulted in “inundation regime” impacts, placing the erosional capacity of wave energy well above the substrate. As a result, incoming surge resulted in sand deposition via overwash. Surge return, however, caused channelized erosion on the backshore and foredune. Small breaches were generated at multiple locations, but these too appear to have occurred during surge return. This presentation provides data on the storm’s impact on that geomorphology by comparing LiDAR-generated digital elevation models before and after the storm.
Prior to the storm, geomorphology mapping was undertaken, using UAV-based LiDAR and ground-penetrating radar (GPR), to characterize the coast prior to a major event. That event, unfortunately, came too early with the passage of Ian, preventing a thorough assessment of the pre-storm condition. Nonetheless, this prescient research program provided unique insights into the storm’s effect. Geographically, field work has focused, along the Lee and Collier County coasts, with more extensive work occurring on Sanibel, Fort Myers Beach, Lovers Key, and Naples. GPR was used to characterize subsurface lithosomes in recognized erosional hot spots from earlier storm impacts (e.g., surge channelization caused by Hurricane Charley on North Captiva, Santiva [westernmost Sanibel Island], and Lovers Key), and in depositional strandplains (e.g., Bowman’s Beach, Sanibel; south Keewaydin). This provided stratigraphic signatures for comparison to lithosomes generated by Ian. LiDAR data were collected prior to Ian to produce digital elevation models (DEMs) for these areas. Post-Ian LiDAR flights are underway. Preliminary results demonstrate that massive landward transport and deposition of sediment occurred, which has grossly altered the topography of the backshore, foredune, and backdune. DEMs also document the return storm surge channelization of the foredune, backshore, and foreshore. Interestingly, these seaward-flow channels developed along the traces of anthropogenic trails cut across the dunes for beach access. GPR surveys of the post-Ian condition are scheduled for late spring 2023. Nonetheless, we believe the storm-surge channels, recorded in GPR traces caused by former storms, also represent this same surge-return phenomenon.
February 21, 2023
Paul Knorr
Bureau of Ocean Energy Management
Topic: Marine minerals
2022 Seminars
November 15, 2022
Dr. Robert Poirier, Research Geologist
USGS Florence Bascom Geoscience Center
"Refining the age of late Quaternary marine deposits in Florida: implications for previous dating studies and future sea-level rise projections"
Abstract
The age and stratigraphic relationships of several late Quaternary paleo-reef tracts in the Florida Keys are relatively well-constrained in time, being dated to at least the last several interglacial periods. For example, the Q5e reef tract, equivalent to the Key Largo and Miami Limestones, has been dated extensively to the last interglacial period (~80-130 kiloannum [ka]). During this interglacial period, also known as Marine Isotope Stage (MIS) 5, globally averaged eustatic sea level is thought to have peaked between ~118-125 ka, with local (relative) sea level reaching between 6-9m above present in the Florida Keys. Several other stratigraphically older paleo-reef tracts have been dated to the penultimate interglacial period (i.e., Q4 reef tract dated to MIS 7 - ~200-240 ka), and possibly at least one additional late Quaternary interglacial period, possible corresponding with either MIS 9 or MIS 11 (Q3 reef tract). Relative sea level elevations during those time periods are less well-constrained, but likely reached as high as ~3-5m and ~14-15m above present, respectively. Despite the many ages generated between Miami and the Florida Keys, only a limited number of attempts have been made to date marine deposits in mainland Florida. All of the available published dates north of the Keys were open-system, meaning there has been some gain and/or loss of 238U, 234U, and/or 230Th at some point since the associated fossil corals died. Furthermore, in some areas the inferred ages from open-system results conflict with those generated alternative dating methods. I present new U-Th results from six sites throughout Florida (submitted to Quaternary Science Reviews), which include the first closed-system U-Th coral dates (i.e., likely little to no post-depositional alteration) from north of the Florida Keys. These dates confirm correlation with the Q5e reef-tract on mainland Florida and can be associated with an apparent paleo-shoreline with a toe that reaches ~7-8m above present. Additional insights from new open-system U-Th coral dates also suggest correlation with both older and younger paleo-reef tracts from the Florida Keys, each with associated paleo-shorelines. While Florida chronology will continue to be a major focus of research, I will discuss several implications related to the application of other dating methods in southern Florida; background rates of land-subsidence related to post-glacial isostatic adjustment; and future sea-level rise projections.
October 18, 2022
Dr. Nora
USGS Pacific Coastal and Marine Science Center
"Sediment routing across the southern Cascadia subduction margin and its implications for understanding earthquake records"
Abstract
Megathrust earthquakes along the Cascadia Subduction Zone have the potential to remobilize significant volumes of sediment, yet the provenance and evolving dispersal patterns of sediment in response to earthquake shaking (or any other trigger) remain unconstrained. Sediment cores and geophysical data from the offshore Eel River forearc basin reveal a robust Pleistocene–Holocene stratigraphic record with differences in sedimentation that can be linked to sea level fluctuations. These new data show thick, regionally extensive accumulation of late Pleistocene to Holocene sediment on the mid-slope, while cores collected within and at the head of Klamath Canyon, located on the seaward edge of Eel River Basin, do not contain Holocene event deposits or any evidence of sediment bypass. This suggests a lack of connectivity of the basin to this lower-slope canyon during present highstand sea level and challenges the conventional model of shelf-to-abyssal plain sediment transfer in southern Cascadia.
Additionally, we use detrital zircon (DZ) U-Pb geochronology as a provenance tracer of onshore rivers, whose catchments contain distinct geologic units with unique U-Pb age distributions, that deliver sand offshore. Mixture modeling results show that the offshore Eel River Basin DZ U-Pb distributions can be statistically characterized by the Eel, Mad, Klamath, and Smith River sources. There is no evidence of Rogue River contributing sand to the basin. Contrary to previous studies, DZ U-Pb geochronology results indicate that the Klamath River, rather than the Eel River, is the dominant source of sand to the Eel River Basin. The disconnect in sediment pathways between the upper slope and the subduction front suggests more local sources to abyssal turbidites in southern Cascadia and indicates that we need to re-evaluate the existing model of shelf to deep-sea sediment transport for earthquake triggered sediment remobilization and seismo-turbidite emplacement
August 16, 2022
Dr. John Warner
USGS Woods Hole Coastal and Marine Science Center
"Development and Applications of an Ocean, Infragravity Wave, Morphological, and Structural Response Coupled Nearshore Prediction System"
Abstract
Prediction of extreme storms and their local effects on geomorphology, habitat, and infrastructure are crucial for effective management decisions and to provide early warning for evacuations and to minimize loss of life and property. The National Oceanographic Partnership Program (NOPP) Hurricanes Coastal Impacts (NHCI) project is providing a unique opportunity that combines significant cross-discipline efforts. Here we describe the Coupled Ocean Atmosphere Waves Sediment Transport (COAWST) numerical modeling system where we have recently added a nearshore infragravity wave model (InWave), implemented a 5th order sediment bed elevation updating scheme, included an implicit vertical advection algorithm, integrated a vegetation module, and linked to a statistical structure response algorithm. The model is applied to idealized and realistic applications with a focus on Hurricane Michael (2018) and demonstrate the necessity of including small scale (order several meters) land features such as vegetation cover that modify breaching behavior. Impacts to coastal structures near Mexico Beach, FL are characterized based on predicted damage assessments. Accurate predictions of impacts to these realistic systems requires high resolution nearshore and coastal information of landcover, structure types, bathymetry, topography, and oceanographic observations for comparison to model predictions. This study demonstrates the importance of coupling waves, currents, and coastal land use to predict nearshore morphological change and coastal structure impacts.
June 21, 2022
Alisha Ellis
USGS St. Petersburg Coastal and Marine Science Center
"Identifying and constraining marsh-type transitions in response to an increasingly erosive shoreline over the past century (Grand Bay, Mississippi-Alabama)"
Dr. James Evans
USGS St. Petersburg Coastal and Marine Science Center
"The potential role of biofilms in the spread of stony coral tissue loss disease (SCTLD) into new regions"
May 17, 2022
Dr. Laura D’Acunto, Ecologist
USGS Wetland and Aquatic Research Center
"Co-creating predictive models to meet conservation needs in the Everglades"
Abstract
Predictive ecological models can be powerful tools to support decisions about conservation actions, species management, or choosing between competing restoration plans. Models are most effective when the model is well understood by its users and can generate outputs that easily translate into a manager’s or practitioner’s decision criteria. The process of co-creating predictive models involves engaging the end users of the models throughout the model creation process. This results in a model that is more likely to be trusted and utilized by its intended users. Laura will discuss several predictive models they developed at USGS under this co-creation process to support Everglades restoration.
March 15, 2022
Dr. Benjamin Norris
USGS Pacific Coastal Marine Science Center
The Role of Mangrove Forests and Coral Reefs in Enhancing Coastal Resilience
Natural habitats such as coral reefs and mangrove forests protect coastal communities against the impacts of waves, thereby mitigating hazards such as flooding and erosion. These valuable ecosystem services are the result of characteristic bio-physical feedbacks between the physical roughness of the ecosystem and the hydrodynamics within coastal zone. This feedback generates turbulence at the scale of the roughness elements, modifying wave energy and sediment transport. Here we investigate the evolution of turbulence in mangrove and coral reef systems to explore these feedback mechanisms and develop an understanding of their role in enhancing coastal resilience. In mangroves, we discover that long-period infragravity waves have the greatest effect on turbulence and sediment transport at the scale of the mangrove roots. Changes in the across-shore intensity of turbulence suggest a feedback mechanism that enables the forest to prograde seaward with time. In coral reefs, we explore the potential for restoration by comparing the hydrodynamics of natural seabed roughness at two locations, representing a hypothetical “pre” and “post” restoration state. We determine that increasing seabed roughness would enhance short-period wave dissipation by one half to one order of magnitude, or by 45% per across-shore meter of restoration.
January 18 2022
Rangley C. Mickey
USGS St. Pete Coastal and Marine Science Center
"Generation of a topo-bathy profile and metric database for the Atlantic and Gulf sandy coastlines"
Abstract
Rangley (R.C.) Mickey is a Physical Scientist that works with the coastal hazards group at St. Pete. He started working at the USGS SPCMSC after completing his Master's Degree at Coastal Carolina University in Conway, SC. His research with the coastal hazards group focuses on morphodynamic and hydrodynamic modeling related storm events on sandy coastlines. He works with various colleagues on projects related to hindcasting and forecasting major storm events to inform coastal restoration studies. His recent work, and a portion of which he will present on, has been to lead a Coop with USGS and Deltares scientist to develop a probabilistic model that can predict magnitudes of morphologic change prior to landfall of tropical storms and hurricanes on the Atlantic and Gulf coasts. This work is an expansion of the existing operational model that predicts the probability of coastal erosion, overwash, and inundation.
Please see our upcoming seminar schedule.
Seminar recordings can be requested by contacting mitzkin@usgs.gov.