Christopher Sherwood, PhD
Coastal oceanographer with expertise in measuring and modeling sediment transport and coastal morphology changes.
Biography
Education
Ph.D. Geological Oceanography, University of Washington, Seattle, Washington 1995
M.S. Geological Oceanography, University of Washington, Seattle, Washington 1982
A.B. Economics and Environmental Studies, Bowdoin College, Brunswick, Maine 1976
Employment
Research Oceanographer, U.S. Geological Survey, Menlo Park, CA and Woods Hole, MA, 1999 – present.
Affiliate Faculty, Ocean Engineering, University of New Hampshire, Durham, NH, 2009 – present
Guest Investigator, Applied Ocean Physics & Engineering, Woods Hole Oceanographic Institution, Woods Hole, MA, 2011 – present
Senior Research Scientist, Commonwealth Scientific and Industrial Research Organisation, Hobart, Tasmania, 1996 – 1999
Senior Research Scientist, Battelle Marine Sciences Laboratory, Richland and Sequim, WA, 1991 – 1996
Science and Products
Remote Sensing Coastal Change
We use remote-sensing technologies—such as aerial photography, satellite imagery, structure-from-motion (SfM) photogrammetry, and lidar (laser-based surveying)—to measure coastal change along U.S. shorelines.
Morphologic changes from sound-side inundation of North Core Banks, NC during Hurricane Dorian
Morphologic changes from sound-side inundation of North Core Banks, Cape Lookout National Seashore, North Carolina, during Hurricane Dorian
Using Video Imagery to Study Head of the Meadow Beach
Two video cameras are mounted on a bluff near Head of the Meadow Beach, Cape Cod National Seashore, North Truro, MA. One camera looks alongshore toward the north-northeast, and the second looks directly offshore (northeast). The cameras are part of a U.S. Geological Survey research project to study the beach and nearshore environment shared by beachgoers, shorebirds, seals, and sharks. The...
Using Video Imagery to Study Head of the Meadow Beach
Two video cameras are mounted on a bluff near Head of the Meadow Beach, Cape Cod National Seashore, North Truro, MA. One camera looks alongshore toward the north-northeast, and the second looks directly offshore (northeast). The cameras are part of a U.S. Geological Survey research project to study the beach and nearshore environment shared by beachgoers, shorebirds, seals, and sharks. The...
Sea Floor Stress and Sediment Mobility Database
The U.S. Geological Survey Sea Floor Stress and Sediment Mobility Database contains estimates of wave-current bottom stress and sediment mobility for the U.S. Atlantic and Gulf Coast continental shelf regions.
Coastal Model Applications and Field Measurements- Field Measurements and Model Applications
Several components of this project are applications to evaluate the model against critical field measurements or to test new model components. Data from field measurements is described in our publications and available in our databases.
Coastal Model Applications and Field Measurements- Advances in Instrumentation
Ongoing acquisition of new instruments and development of analytical methods provides us with the means to make better observations of coastal ocean processes. The measurements provide us with insight and data for critical evaluation of model performance. Advances in a range of measurement capabilities, including bottom stress, sediment erodibility, water properties and nutrient concentrations...
Coastal Model Applications and Field Measurements- Ocean Model Contributions
The U.S. Geological Survey (USGS) and Woods Hole Oceanographic Institution (WHOI) led a project funded by the National Oceanographic Partnership Program (NOPP) with support from the Office of Naval Research (ONR) and the National Science Foundation (NSF), to develop a community sediment-transport modeling system (CSTMS).
Coastal Model Applications and Field Measurements
Numerical models are used by scientists, engineers, coastal managers, and the public to understand and predict processes in the coastal ocean. This project supports the development and application of open-source coastal models and has several objectives: 1) improve the code of numerical sediment-transport models by implementing new or improved algorithms; 2) obtain measurements of coastal...
Mapping Land-Use, Hazard Vulnerability and Habitat Suitability Using Deep Neural Networks
Deep learning is a computer analysis technique inspired by the human brain’s ability to learn. It involves several layers of artificial neural networks to learn and subsequently recognize patterns in data, forming the basis of many state-of-the-art applications from self-driving cars to drug discovery and cancer detection. Deep neural networks are capable of learning many levels of abstraction...
Exploring the USGS Science Data Life Cycle in the Cloud
Executive Summary Traditionally in the USGS, data is processed and analyzed on local researcher computers, then moved to centralized, remote computers for preservation and publishing (ScienceBase, Pubs Warehouse). This approach requires each researcher to have the necessary hardware and software for processing and analysis, and also to bring all external data required for the workflow over the...
Community Model for Coastal Sediment Transport
This project is complete and the website is archived and no longer updated.
The U.S. Geological Survey and others are promoting the development of an open-source numerical model for sediment-transport in coastal regions. We are collaborating with other federal agencies...
Geotagged Low-Altitude Aerial Imagery From Unmanned Aerial System Flights Over Town Neck Beach, in Sandwich, Massachusetts, on February 11, 2016
Low-altitude (30-120 meters above ground level) digital images of Town Neck Beach in Sandwich, Massachusetts, were obtained with a series of cameras mounted on small unmanned aerial systems (UAS, also known as a drone). Imagery was collected at close to low tide on five days to observe changes in beach and dune morphology. The images were geolocated by using the single-frequency geo
Geotagged Low-Altitude Aerial Imagery From Unmanned Aerial Systems Flights Over Town Neck Beach, in Sandwich, Massachusetts, on January 25, 2016
Low-altitude (30-120 meters above ground level) digital images of Town Neck Beach in Sandwich, Massachusetts, were obtained with a series of cameras mounted on small unmanned aerial systems (UAS, also known as a drone). Imagery was collected at close to low tide on five days to observe changes in beach and dune morphology. The images were geolocated by using the single-frequency geo
Oceanographic, Atmospheric and Water-Quality Measurements Sandwich Town Neck Beach, Massachusetts, 2016
These measurements provide information about waves, tides, and overwash during a winter storm in January 2016; about waves, tides, currents, and water properties between February and May, 2016; and about waves and tides between May and June 2016, during a period that overlaps with offshore bathymetric surveys.
Oceanographic, Atmospheric and Water-Quality Measurements Sandwich Town Neck Beach, Massachusetts, 2017
These measurements provide short-duration datasets of waves, tides, and overwash from portable pressure sensors deployed on the beach during major winter storms on these dates: January 23-26; February 9-10; February 13-15; and March 13-15, 2017. Longer datasets were obtained from sensors on a platform deployed on the seafloor north of the beach in seven meters depth.
Sidescan sonar, single beam bathymetry, and navigation collected offshore of Sandwich Beach in 2016, U.S. Geological Field Activity 2016-030-FA
The objectives of the survey were to provide bathymetric and sidescan sonar data for sediment transport studies and coastal change model development for ongoing studies of nearshore coastal dynamics along Sandwich Town Neck Beach, MA. Data collection equipment used for this investigation are mounted on an unmanned surface vehicle (USV) uniquely adapted from a commercially sold gas-powered...
Aerial imagery and photogrammetric products from unmanned aerial systems (UAS) flights over the Lake Ontario shoreline at Sodus Bay, New York, July 12 to 14, 2017
This data release includes images tagged with locations determined from the UAS GPS; tables with updated estimates of camera positions and attitudes based on the photogrammetric reconstruction; tables listing locations of the base stations, ground control points, and transect points; geolocated, RGB-colored point clouds; orthomosaic images; and digital elevation models for each of the regions...
Aerial imagery and photogrammetric products from unmanned aerial systems (UAS) flights over the Lake Ontario shoreline at Sodus Bay, New York, July 12 to 14, 2017
This data release includes images tagged with locations determined from the UAS GPS; tables with updated estimates of camera positions and attitudes based on the photogrammetric reconstruction; tables listing locations of the base stations, ground control points, and transect points; geolocated, RGB-colored point clouds; orthomosaic images; and digital elevation models for each of the regions...
Point cloud from low-altitude aerial imagery from unmanned aerial system (UAS) flights over Coast Guard Beach, Nauset Spit, Nauset Inlet, and Nauset Marsh, Cape Cod National Seashore, Eastham, Massachusetts on 1 March 2016 (LAZ file)
This point cloud was derived from low-altitude aerial images collected from an unmanned aerial system (UAS) flown in the Cape Cod National Seashore on 1 March, 2016. The objective of the project was to evaluate the quality and cost of mapping from UAS images. The point cloud contains 434,096,824 unclassifed and unedited geolocated points.
Water level measurements collected in West Falmouth Harbor, MA, 2017
Water-level gauges were deployed at two sites in West Falmouth Harbor between April and June 2017. One gauge was mounted under the town-owned West Falmouth boat dock and the other on the private Associates dock near the mouth of the Harbor. Data from the upper sensor at the Associates dock were used to make atmospheric pressure corrections at both sites.
Investigating bedload transport under asymmetrical waves using a coupled ocean-wave model
Transport by asymmetrical wave motions plays a key role in cross-shore movement of sand, which is important for bar migration, exchange through tidal inlets, and beach recovery after storms. We have implemented a modified version of the SANTOSS formulation in the three-dimensional open-source Coupled-Ocean-Atmosphere-Wave-Sediment Transport (...
Kalra, Tarandeep S.; Sherwood, Christopher R.; Warner, John C.; Rafati, Yashar; Hsu, Tian Jian Modeling the morphological response of a barrier island to Hurricane Matthew
Surge and wave forcing from Hurricane Matthew caused a breach south of Matanzas Inlet (FL, USA) on a complex barrier island, including sandy dunes, hard structures (residential buildings and a highway), wetlands, and the US Intracoastal Waterway. In this paper, the skill of the XBeach model to predict hurricane-induced barrier island overwash,...
Quataert, Ellen; van der Lugt, Marlies; Sherwood, Christopher R.; van Oormondt, Maarten; van Dongeran, Ap Wave-current interaction between Hurricane Matthew wave fields and the Gulf Stream
Hurricanes interact with the Gulf Stream in the South Atlantic Bight (SAB) through a wide variety of processes, which are crucial to understand for prediction of open-ocean and coastal hazards during storms. However, it remains unclear how waves are modified by large-scale ocean currents under storm conditions, when waves are aligned with the...
Hegermiller, Christie; Warner, John C.; Olabarrieta, Maitane; Sherwood, Christopher R. Morphodynamic modeling of the response of two barrier islands to Atlantic hurricane forcing
The accurate prediction of a barrier island response to storms is challenging because of the complex interaction between hydro- and morphodynamic processes that changes at different stages during an event. Assessment of the predictive skill is further complicated because of uncertainty in the hydraulic forcing, initial conditions, and the...
van der Lugt, Marlies; Quataert, Ellen; van Dongeren, Ap; van Ormondt, Maarten; Sherwood, Christopher R. Tidal variation in cohesive sediment distribution in an idealized, partially-mixed estuary
Particle settling velocity and erodibility are key factors that govern the transport of sediment through coastal environments including estuaries. These are difficult to parameterize in models that represent mud, whose properties can change in response to many factors, including tidally varying suspended sediment concentration (SSC) and shear...
Tarpley, D.; Harris, Courtney K.; Friedrichs, Carl T.; Sherwood, Christopher R.
Unmanned aerial systems capabilities of the U.S. Geological Survey Woods Hole Coastal and Marine Science Center
Unmanned aerial system (UAS) technology provides a rapid and low-cost solution for mapping coastal environments and assessing short- and long-term changes. The interdisciplinary nature of the data collected and the breadth of applications make UAS technology applicable to multiple scientific investigations. The Aerial Imaging and Mapping (AIM)...
Brosnahan, Sandra; Sherwood, Christopher R. Advantages and limitations to the use of optical measurements to study sediment properties
Measurements of optical properties have been used for decades to study particle distributions in the ocean. They are useful for estimating suspended mass concentration as well as particle-related properties such as size, composition, packing (particle porosity or density), and settling velocity. Measurements of optical properties are, however,...
Boss, Emmanuel; Sherwood, Christopher R.; Hill, Paul; Milligan, Tim Rapid, remote assessment of Hurricane Matthew impacts using four-dimensional structure-from-motion photogrammetry
Timely assessment of coastal landforms and structures after storms is important for evaluating storm impacts, aiding emergency response and restoration, and initializing and assessing morphological models. Four-dimensional multiview photogrammetry, also known as structure from motion (4D SfM), provides a method for generating three-dimensional...
Sherwood, Christopher R.; Warrick, Jonathan; Hill, Andrew D.; Ritchie, Andrew C.; Andrews, Brian D.; Plant, Nathaniel G. Reductive dechlorination rates of 4,4′-DDE (1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethenyl]benzene) in sediments of the Palos Verdes Shelf, CA
Wastes from the world's largest manufacturer of DDT (1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene) were released into the Los Angeles County municipal sewer system from 1947 to 1971. Following primary treatment, the effluent was discharged through a submarine outfall system whereupon a portion of the DDT and associated degradation...
Eganhouse, Robert P.; Sherwood, Christopher R.; Pontolillo, James; Edwards, Brian; Dickhudt, Patrick J. Numerical model of geochronological tracers for deposition and reworking applied to the Mississippi subaqueous delta
Measurements of naturally occurring, short-lived radioisotopes from sediment cores on the Mississippi subaqueous delta have been used to infer event bed characteristics such as depositional thicknesses and accumulation rates. Specifically, the presence of Beryllium-7 (7Be) indicates recent riverine-derived terrestrial sediment deposition; while...
Birchler, Justin J.; Harris, Courtney K.; Kniskern, Tara A.; Sherwood, Christopher R. Direct measurements of mean Reynolds stress and ripple roughness in the presence of energetic forcing by surface waves
Direct covariance observations of the mean flow Reynolds stress and sonar images of the seafloor collected on a wave‐exposed inner continental shelf demonstrate that the drag exerted by the seabed on the overlying flow is consistent with boundary layer models for wave‐current interaction, provided that the orientation and anisotropy of the bed...
Scully, Malcolm; Trowbridge, John; Sherwood, Christopher R.; Jones, Katie R.; Traykovski, Peter A. Final data report for factors controlling DDE dechlorination rates on the Palos Verdes Shelf: A field and laboratory investigation
This data report provides a compilation of information developed over the last 6+ years by a multi-disciplinary, multi-institutional research team. The overall goal of this work has been to identify the biological, chemical, and physical factors that control rates of reductive dechlorination of DDE and DDMU in sediments of the Palos Verdes Shelf (...
Eganhouse, Robert P.; Pontolillo, James; Orem, William H.; Webster, Daniel M.; Hackley, Paul C.; Edwards, Brian D.; Rosenberger, Kurt J.; Dickhudt, Patrick; Sherwood, Christopher R.; Reinhard, Martin; Qin, Sujie; Dougherty, Jennifer; Hopkins, Gary; Marshall, Ian; Spormann, Alfred
USGS and Army Corps of Engineers conduct simultaneous measurements at Sandy Neck beach, Cape Cod, MA
Woods Hole Coastal and Marine Science Center Aerial Imaging and Mapping (AIM) group conducted drone flights from atop a dune at Sandy Neck (Cape Cod) while the Joint Airborne Lidar Bathymetry Technical Center of Expertise (JALBTCX) aircraft collected data overhead.
Data from Three Recent Studies Released in the USGS Oceanographic Time-Series Data Collection
Three new oceanographic time-series datasets were released in the USGS Oceanographic Time-Series Data Collection.
Coastal and Marine Geology is Airborne!
A number of Coastal and Marine Geology researchers have completed the Unmanned Aerial Systems certification classes held by the Department of Interior Office of Aviation Safety and the USGS Unmanned Aerial Systems program, creating a fast and inexpensive way to make accurate three-dimensional maps and take aerial photos.