Cable, J.E., Smith, C.G., Blanford, W.J. 2009. Dispersivity and distribution coefficients in marine sediments using Tritium and Radium-226. Radioprotection, 44:185-190.
Christopher G Smith
As a coastal geologist, my research focuses on the transport, transformation, and deposition of particulate and dissolved constituents within the coastal realm and how system processes will respond to large-scale environmental forcings (e.g., climate change).
Biography
Coastal systems provide a dynamic interface between terrestrial and marine realms; anthropogenic activity and natural processes occurring within terrestrial ecosystems can have a significant impact to the coastal zone and adjacent marine system. Augmentation of coastal systems is inevitable from a human perspective as nearly half of the population of the United States reside within coastal counties. Understanding modern processes (sedimentologic, hydrologic, and geochemical) occurring along this terrestrial-marine continuum is critical in predicting the response associated with natural and anthropogenic perturbations.
My research interests generally fall into two categories: 1) fluid exchange (e.g., surface water – groundwater exchange, submarine and coastal groundwater discharge) and 2) fine-grained sediment dynamics, specifically in marsh and estuarine environments. Linking these two seemingly disparate research topics are naturally-occurring (e.g., U-Th series) and anthropogenically-introduced/spiked (e.g., 137Cs) radionuclides. Particle reactive radionuclides (e.g., 7Be, 234Th, 210Pb, 210Po, and 137Cs) provide excellent tracers to quantify sediment deposition and re-mobilization over time-scales of months to decades. Examining the final sedimentary product in the context of the temporal framework and associated transient changes also provide a breadth of knowledge to environmental conditions that persisted in recent past and the outcome that may be expected if similar conditions persist in the present or future. Alternatively, the more conservative behavior of radon and radium isotopes have proven these as excellent tracers to quantify groundwater discharge in both fresh and marine environments.
Over the last three decades, groundwater discharge to the coastal zone has received increasing recognition as a substantial material vector, influencing water quality and nutrient fluxes. Quantification of fresh and marine groundwater end-members and the processes that drive the exchange (e.g., seasonal recharge cycles, hurricanes and tropical cyclones) are critical to assess the overall importance of coastal groundwater and has been at the forefront of my research.
Science and Products
Date published: March 7, 2019
Status: Active Alabama Barrier Island Restoration Assessment
This project is a collaborative effort between the USGS, U.S. Army Corps of Engineers (USACE), and the State of Alabama funded by National Fish and Wildlife Foundation (NFWF) to investigate viable, sustainable restoration options that protect and restore the natural resources of Dauphin Island, Alabama. The project is focused on restoration options that protect and restore habitat and living...
Date published: December 28, 2018
Status: Active Hurricane Sandy Response- Linking the Delmarva Peninsula's Geologic Framework to Coastal Vulnerability
The Delmarva Peninsula is a 220-kilometer-long headland, spit, and barrier island complex that was significantly affected by Hurricane Sandy. In order to better constrain controls on coastal vulnerability and evolution, the region’s sediment sources, transport pathways and sediment sinks must be identified. This project defines the geologic framework of the Delmarva coastal system through...
Contacts: Laura Brothers, Ph.D., Elizabeth Pendleton
Date published: October 29, 2018
Status: Active Sea-level and Storm Impacts on Estuarine Environments and Shorelines (SSIEES)
This project assesses the physical controls of sediment and material exchange between wetlands and estuarine environments along the northern Gulf of Mexico (Grand Bay Alabama/Mississippi and Vermilion Bay, Louisiana) and the Atlantic coast (Chincoteague Bay, Virginia/Maryland).
Date published: October 16, 2018
Status: Active Submarine Groundwater Discharge
Submarine groundwater discharge (SGD) is an ubiquitous coastal process that is driven by a composite of climatologic, hydrogeologic, and oceanographic processes. For example, terrestrial hydraulic gradients that reflect both short and long term climatic conditions almost always transport both surface and ground water toward the coast. In coastal waters, physical oceanographic processes such as...
Date published: December 6, 2017
Status: Active Alabama Barrier Island Restoration Study
Scientists are collecting geologic data and developing a numerical model framework to understand the evolution of Dauphin Island over the last 15-20 years and assess the future evolution of the island over the next 15-50 years, including the impacts of potential restoration scenarios.
Attribution: St. Petersburg Coastal and Marine Science Center
Date published: September 20, 2016
Status: Active Improving Our Ability to Forecast Tidal Marsh Response to Sea Level Rise
Our overall objective is to understand what controls the vulnerability of coastal marshes to risks associated with global change drivers and rising sea levels. Fundamental questions pertaining to coastal wetland vulnerability still need to be addressed. What factors explain spatial and geographic variation in tidal wetland vulnerability? How do short term climatic events (storms) influence the...
Year Published: 2018
Assessing the impact of open-ocean and back-barrier shoreline change on Dauphin Island, Alabama, at multiple time scales over the last 75 years
Dauphin Island and Little Dauphin Island, collectively, make up a geomorphically complex barrier island system located along Alabama’s southern coast, separating Mississippi Sound from the Gulf of Mexico and Mobile Bay. The barrier island system provides numerous economical (tourism, fisheries) and natural (habitat for migratory birds, natural...
Smith, Christopher G.; Long, Joseph W.; Henderson, Rachel E.; Nelson, Paul R.Attribution: St. Petersburg Coastal and Marine Science Center
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Smith, C.G., Long, J.W., Henderson, R.E., and Nelson, P.R., 2018, Assessing the impact of open-ocean and back-barrier shoreline change on Dauphin Island, Alabama, at multiple time scales over the last 75 years: U.S. Geological Survey Open-File Report 2018–1170, 20 p., https://doi.org/10.3133/ofr20181170.
Year Published: 2018
The effects of tropical cyclone-generated deposition on the sustainability of the Pearl River marsh, Louisiana: The importance of the geologic framework
Shoreline retreat is a tremendously important issue along the coast of the northern Gulf of Mexico, especially in Louisiana. Although this marine transgression results from a variety of causes, the crucial factor is the difference between marsh surface elevation and rising sea levels. In most cases, the primary cause of a marsh's inability to keep...
McCloskey, Terrence A.; Smith, Christopher G.; Liu, Kam-Biu; Nelson, Paul R.Attribution: Wetland and Aquatic Research Center, Ecosystems
Year Published: 2018
The foraminifera of Chincoteague Bay, Assateague Island, and the surrounding areas: A regional distribution study
Foraminiferal census data from Chincoteague Bay, Newport Bay, the salt marshes of Assateague Island, adjacent mainland salt marshes, and the inner-shelf, were assessed to determine the current assemblages in Chincoteague Bay, and how the different environments surrounding the bay, and the gradients within the bay, influence the microfossil...
Smith, Christopher G.; Ellis, Alisha M.; Shaw, Jaimie E.; Osterman, Lisa E.; Smith, Christopher G.Attribution: St. Petersburg Coastal and Marine Science Center
Year Published: 2018
Barrier-island and estuarine-wetland physical-change assessment after Hurricane Sandy
IntroductionThe Nation’s eastern coast is fringed by beaches, dunes, barrier islands, wetlands, and bluffs. These natural coastal barriers provide critical benefits and services, and can mitigate the impact of storms, erosion, and sea-level rise on our coastal communities. Waves and storm surge resulting from Hurricane Sandy, which made landfall...
Plant, Nathaniel G.; Smith, Kathryn E.L.; Passeri, Davina L.; Smith, Christopher G.; Bernier, Julie C.Attribution: St. Petersburg Coastal and Marine Science Center
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Plant, N.G., Smith, K.E.L., Passeri, D.L., Smith, C.G., and Bernier, J.C., 2018, Barrier-island and estuarine-wetland physical-change assessment after Hurricane Sandy: U.S. Geological Survey Open-File Report 2017–1157, 36 p., https://doi.org/10.3133/ofr20171157.
Year Published: 2018
The sedimentological characteristics and geochronology of the marshes of Dauphin Island, Alabama
In August 2015, scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center collected 11 push cores from the marshes of Dauphin Island and Little Dauphin Island, Alabama. Sample site environments included high marshes, low salt marshes, and salt flats, and varied in distance from the shoreline. The sampling efforts...
Ellis, Alisha M.; Smith, Christopher G.; Marot, Marci E.Attribution: St. Petersburg Coastal and Marine Science Center
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Ellis, A.M., Smith, C.G., and Marot, M.E., 2018, The sedimentological characteristics and geochronology of the marshes of Dauphin Island, Alabama: U.S. Geological Survey Open-File Report 2017–1165, https://doi.org/10.3133/ofr20171165.
Year Published: 2018
How could a freshwater swamp produce a chemical signature characteristic of a saltmarsh?
Reduction–oxidation (redox) reaction conditions, which are of great importance for the soil chemistry of coastal marshes, can be temporally dynamic. We present a transect of cores from northwest Florida wherein radical postdepositional changes in the redox regime has created atypical geochemical profiles at the bottom of the sedimentary column....
McCloskey, Terrence A.; Smith, Christopher G.; Liu, Kam-biu; Marot, Marci E.; Haller, ChristianAttribution: St. Petersburg Coastal and Marine Science Center
Year Published: 2017
Single-beam bathymetry data collected in 2015 from Grand Bay, Alabama-Mississippi
As part of the Sea-level and Storm Impacts on Estuarine Environments and Shorelines (SSIEES) project, scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted a single-beam bathymetry survey within the estuarine, open-bay, and tidal creek environments of Grand Bay, Alabama-Mississippi, from May...
DeWitt, Nancy T.; Stalk, Chelsea A.; Smith, Christopher G.; Locker, Stanley D.; Fredericks, Jake J.; McCloskey, Terrence A.; Wheaton, Cathryn J.Attribution: St. Petersburg Coastal and Marine Science Center
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DeWitt, N.T., Stalk, C.A., Smith, C.G., Locker, S.D., Fredericks, J.J., McCloskey, T.A., and Wheaton, C.J., 2017, Single-beam bathymetry data collected in 2015 from Grand Bay, Alabama-Mississippi: U.S. Geological Survey Data Series 1070, https://doi.org/10.3133/ds1070.
Year Published: 2017
A seasonal and spatial comparison of metals, and stable carbon and nitrogen isotopes, in Chincoteague Bay and the marsh deposits of Assateague Island and the adjacent vicinity, Maryland and Virginia
After Hurricane Sandy, scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of estuarine, marsh, and sandy overwash surface sediments from Chincoteague Bay, Tom’s Cove, and the surrounding Assateague Island and Delmarva Peninsula in March–April and October 2014. Surplus...
Ellis, Alisha M.; Smith, Christopher G.Attribution: St. Petersburg Coastal and Marine Science Center
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Ellis, A.M., and Smith, C.G., 2017, A seasonal and spatial comparison of metals, and stable carbon and nitrogen isotopes, in Chincoteague Bay and the marsh deposits of Assateague Island and the adjacent vicinity, Maryland and Virginia: U.S. Geological Survey Data Series 1059, https://doi.org/10.3133/ds1059.
Year Published: 2017
Distribution of foraminifera in Chincoteague Bay and the marshes of Assateague Island and the adjacent vicinity, Maryland and Virginia
Scientists from the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of estuarine, marsh, and sandy washover surface sediments from Chincoteague Bay, Tom’s Cove, and the surrounding Assateague Island and Delmarva Peninsula in March–April and October 2014, after Hurricane Sandy....
Ellis, Alisha M.; Shaw, Jaimie; Osterman, Lisa E.; Smith, Christopher G.Attribution: St. Petersburg Coastal and Marine Science Center
View Citation
Ellis, A.M., Shaw, J.E., Osterman, L.E., and Smith, C.G., 2017, Distribution of foraminifera in Chincoteague Bay and the marshes of Assateague Island and the adjacent vicinity, Maryland and Virginia: U.S. Geological Survey Data Series 1060, available at https://doi.org/10.3133/ds1060.
Year Published: 2017
The magnitude and origin of groundwater discharge to eastern U.S. and Gulf of Mexico coastal waters
Fresh groundwater discharge to coastal environments contributes to the physical and chemical conditions of coastal waters, but the role of coastal groundwater at regional to continental scales remains poorly defined due to diverse hydrologic conditions and the difficulty of tracking coastal groundwater flow paths through heterogeneous subsurface...
Befus, Kevin; Kroeger, Kevin D.; Smith, Christopher G.; Swarzenski, Peter W.Attribution: Woods Hole Coastal and Marine Science Center
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Befus, K. M., Kroeger, K. D., Smith, C. G., & Swarzenski, P. W. (2017). The magnitude and origin of groundwater discharge to eastern U.S. and Gulf of Mexico coastal waters. Geophysical Research Letters, 44. https://doi.org/10.1002/2017GL075238
Year Published: 2017
Archive of sediment physical properties and grain-size data for sediment samples collected offshore of Assateague Island, Maryland and Virginia:
This data release serves as an archive of sediment physical properties and grain-size data for surficial samples collected offshore of Assateague Island, Maryland and Virginia, for comparison with surficial estuarine and subaerial sedimentological samples collected and assessed following Hurricane Sandy (Ellis and others, 2015; Smith and others,...
Ellis, Alisha M.; Wheaton, Cathryn J.; Smith, Christopher G.Attribution: St. Petersburg Coastal and Marine Science Center
View Citation
Ellis, A.M., Wheaton, C.J., Smith, C.G., 2017, Archive of sediment physical properties and grain-size data for sediment samples collected offshore of Assateague Island, Maryland and Virginia: U.S. Geological Survey data release, https://doi.org/10.5066/F7HX19WB.
Year Published: 2017
Hydrological data concerning submarine groundwater discharge along the western margin of Indian River Lagoon, east-central Florida - December 2016 and January 2017
Indian River Lagoon, one of the most biologically diverse estuarine systems in the continental United States, is a shallow brackish lagoon stretching along approximately 200 kilometers (km) of the Atlantic coast of central Florida. Lagoon width varies from ~0.5 – 9.0 km, with substantial human infrastructure lining both shores. Scientists from the...
McCloskey, Terrence A.; Smith, Christopher G.; Zaremba, Nicholas; McBride, Elsie; Everhart, CheyenneAttribution: St. Petersburg Coastal and Marine Science Center
View Citation
McCloskey, T.A., Smith, C.G., Zaremba, N.J., McBride, E., and Everhart, C., 2017, Hydrological data concerning submarine groundwater discharge along the western margin of Indian River Lagoon, east-central Florida - December 2016 and January 2017: U.S. Geological Survey data release, https://doi.org/10.5066/F7PZ5725.
Pre-USGS Publications
Smith, C.G., Cable, J.E., Martin, J.B., and Roy, M. 2008. Evaluating the source and seasonality of submarine groundwater discharge using a Radon-222 pore water transport model, Earth and Planetary Science Letters 273:312-322.
Culver, S.J., Grand Pre, C., Mallinson, D., Riggs, S., Corbett, D.R., Foley, J., Hale, M., Ricardo, J., Rosenberger, J., Smith, C.G., Smith, C.W., Snyder, S., Twamley, D., Farrell, K., Horton, B. 2007. Late Holocene barrier island collapse: Outer Banks, North Carolina, U.S.A. The Sedimentary Record 5:4-8.
Smith, C.G., Cable, J.E., Martin, J.B. 2008. Episodic high intensity mixing events in a subterranean estuary: Effects of tropical cyclones, Limnology and Oceanography 53:666-674.
Smith, C.G., Culver, S.J., Riggs, S.R., Ames, D., Corbett, D.R., Mallinson, D.J. 2008. Geospatial analysis of barrier island width of two segments of the Outer Banks, North Carolina, USA: anthropogenic curtailment of natural self-sustaining processes. Journal of Coastal Research 24:70-83.
Martin, J.B., Cable, J., Smith, C.G., Roy, M. and Cherrier, J. 2007. Magnitudes of submarine groundwater discharge from marine and terrestrial sources: Indian River Lagoon, Florida. Water Resources Research 43: doi:10.1029/2006WR005266.
Smith, C.G., Cable, J.E., Martin, J.B., Cherrier, J., and Roy, M. 2006. Mixing in the subterranean estuary: a comparison of Radon-222 pore water models. p. 355-368, In V. P. Singh and Y. J. Xu [eds.], Annual American Institute of Hydrology Meeting & International Conference: Challenges in Coastal Hydrology and Water Quality. Water Resources Publications, LLC, 534 pp.
Martin, J.B., Cable, J.E., Jaeger, J., Hartl, K.M., and Smith, C.G. 2006. Thermal and chemical evidence for rapid water exchange across the sediment-water interface by bioirrigation in the Indian River Lagoon, Florida. Limnology and Oceanography 51:1332-1341.
Culver, S.J., Ames, D.V., Corbett, D.R., Malllinson, D., Riggs, S.R., Smith, C.G., and Vance, D. 2005. Foraminiferal and sedimentary record of late Holocene barrier island evolution, Pea Island, North Carolina. Journal of Coastal Research 21:406-416.
Date published: May 17, 2019
Collaborative research will advance knowledge on coastal erosion hazards of marsh shorelines and the impact of living shorelines
Coastal wetland loss has been well documented and attributed to many factors, including increased shoreline erosion from human activities, sea level rise, and storms.