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Julie Bernier

I have worked at the USGS - St. Petersburg Coastal and Marine Science Center since receiving my M.S. in Geology from the University of Utah in 2003. My research interests include applying sedimentologic, stratigraphic, remote sensing, and geophysical techniques to better understand coastal wetland and barrier-island change at historic to geologic time scales.

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Filter Total Items: 15
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An island with sections of short grasses has been covered by a large sand fan that was washed landward by waves.

Storm-Related Barrier Island Morphological Evolution

Storms quickly and dramatically alter barrier island environments by changing adjacent seafloor morphology, eroding beaches, scarping or leveling dunes, and sometimes creating new inlets. Measuring the magnitude of barrier island sediment movement during and after storms allows us to track rates of beach recovery, dune growth, and inlet-related alterations to barrier island sediment supply.
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Natural Hazards, Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center
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Storm-Related Barrier Island Morphological Evolution

Storms quickly and dramatically alter barrier island environments by changing adjacent seafloor morphology, eroding beaches, scarping or leveling dunes, and sometimes creating new inlets. Measuring the magnitude of barrier island sediment movement during and after storms allows us to track rates of beach recovery, dune growth, and inlet-related alterations to barrier island sediment supply.
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A long barrier island, mainly sandy with some vegetation, has a sediment berm placed along the shoreface.

Barrier Island Sensitivity to Changes in Sediment Supply

Observations and models show that maintaining barrier islands requires a balance between sea-level rise and sediment supply. However, most estimates of sediment supply are not based on modern conditions, which could result in less accurate predictions of sediment fluxes. We explore how natural and human alterations impact modern sediment fluxes, or changes, on barrier islands – research that has...
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Natural Hazards, Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center
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Barrier Island Sensitivity to Changes in Sediment Supply

Observations and models show that maintaining barrier islands requires a balance between sea-level rise and sediment supply. However, most estimates of sediment supply are not based on modern conditions, which could result in less accurate predictions of sediment fluxes. We explore how natural and human alterations impact modern sediment fluxes, or changes, on barrier islands – research that has...
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Scientists operate scientific sediment coring equipment with a tall metal barrel and tripod on a sandy beach near the water.

Coastal Sediment Availability and Flux (CSAF) Capabilities

As part of the Coastal Sediment Availability and Flux project, we use innovative technology and integrate a variety of techniques to characterize barrier island environments, reconstruct their past history, and predict their future vulnerability.
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Natural Hazards, Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center
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Coastal Sediment Availability and Flux (CSAF) Capabilities

As part of the Coastal Sediment Availability and Flux project, we use innovative technology and integrate a variety of techniques to characterize barrier island environments, reconstruct their past history, and predict their future vulnerability.
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Pre- and post- land loss aerial photographs and historical wetland-loss trends at selected lower delta-plain study areas

Historical Wetland Loss - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

Analysis of historical satellite imagery and previously interpreted land-classification datasets identified more than 4,600 km2 of low-lying wetlands in coastal Louisiana that converted to open water between 1932 and 2004.
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St. Petersburg Coastal and Marine Science Center
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Historical Wetland Loss - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

Analysis of historical satellite imagery and previously interpreted land-classification datasets identified more than 4,600 km2 of low-lying wetlands in coastal Louisiana that converted to open water between 1932 and 2004.
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Conceptual diagram showing the stratigraphic relationships used to estimate subsidence and erosion at an open-water core site.

Wetland Subsidence and Erosion - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

The magnitudes of subsidence and erosion at the wetland-loss core sites were estimated by comparing marsh-surface elevations, water depths, and vertical displacements of stratigraphic contacts that were correlated between short sediment cores.
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St. Petersburg Coastal and Marine Science Center
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Wetland Subsidence and Erosion - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

The magnitudes of subsidence and erosion at the wetland-loss core sites were estimated by comparing marsh-surface elevations, water depths, and vertical displacements of stratigraphic contacts that were correlated between short sediment cores.
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Regional map showing historical wetland losses and geologic setting of the Mississippi River delta plain, Louisiana

Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

Research (2000 - 2011) at the St. Petersburg Coastal and Marine Science Center focused on better understanding the physical processes and human activities that contributed to historical wetland loss in coastal Louisiana and the spatial and temporal trends of that loss.
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St. Petersburg Coastal and Marine Science Center
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Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

Research (2000 - 2011) at the St. Petersburg Coastal and Marine Science Center focused on better understanding the physical processes and human activities that contributed to historical wetland loss in coastal Louisiana and the spatial and temporal trends of that loss.
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Sequence of production-related subsurface events that may induce land subsidence and reactivate faults

Induced Subsidence Related to Hydrocarbon Production - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

One of the primary goals of this project was to test the hypothesis that long-term, large-volume hydrocarbon production along the Gulf Coast resulted in land-surface subsidence, reactivation of deep-seated faults, and wetland loss in Texas and Louisiana.
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St. Petersburg Coastal and Marine Science Center
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Induced Subsidence Related to Hydrocarbon Production - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

One of the primary goals of this project was to test the hypothesis that long-term, large-volume hydrocarbon production along the Gulf Coast resulted in land-surface subsidence, reactivation of deep-seated faults, and wetland loss in Texas and Louisiana.
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Example bathymetric grids with superimposed core locations

Historical Accommodation Formation - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

Bathymetric data acquired at the Madison Bay, Point au Chien, Bully Camp, Leeville, Fourchon, Caminada, and Sabine National Wildlife Refuge study areas provided average one-dimensional accommodation distances at those sites. These results were integrated with the two-dimensional extent of historical wetland loss from 1956 to 2004 to estimate the total 3D (volume) accommodation space that formed...
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St. Petersburg Coastal and Marine Science Center
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Historical Accommodation Formation - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

Bathymetric data acquired at the Madison Bay, Point au Chien, Bully Camp, Leeville, Fourchon, Caminada, and Sabine National Wildlife Refuge study areas provided average one-dimensional accommodation distances at those sites. These results were integrated with the two-dimensional extent of historical wetland loss from 1956 to 2004 to estimate the total 3D (volume) accommodation space that formed...
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photos of shallow-water benthic foraminifera

Natural Subsidence and Sea-Level Rise - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

Geologic proxies may shed light on long-term environmental trends and stability of the Louisiana coastal marsh. The combined processes of accretion, sea-level rise and subsidence influence wetland elevation and determine marsh stability.
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St. Petersburg Coastal and Marine Science Center
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Natural Subsidence and Sea-Level Rise - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

Geologic proxies may shed light on long-term environmental trends and stability of the Louisiana coastal marsh. The combined processes of accretion, sea-level rise and subsidence influence wetland elevation and determine marsh stability.
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Jim Flocks and Nick Ferina collect a vibracore

Photo Gallery - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

Gallery of photos taken during fieldwork.
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St. Petersburg Coastal and Marine Science Center
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Photo Gallery - Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin

Gallery of photos taken during fieldwork.
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Photo of Fire Island showing back barrier, dunes, beach, and nearshore environments

Coastal Sediment Availability and Flux (CSAF)

Sediments are the foundation of coastal systems, including barrier islands. Their behavior is driven by not only sediment availability, but also sediment exchanges between barrier island environments. We collect geophysical, remote sensing, and sediment data to estimate these parameters, which are integrated with models to improve prediction of coastal response to extreme storms and sea-level rise...
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Natural Hazards, Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center
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Coastal Sediment Availability and Flux (CSAF)

Sediments are the foundation of coastal systems, including barrier islands. Their behavior is driven by not only sediment availability, but also sediment exchanges between barrier island environments. We collect geophysical, remote sensing, and sediment data to estimate these parameters, which are integrated with models to improve prediction of coastal response to extreme storms and sea-level rise...
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Photo of a larger research vessel towing a smaller one at the beach

Geology and Sediment Availability - Coastal System Change at Fire Island, New York

Sediment supply is a critical control on barrier island vulnerability and resilience over a variety of time scales (e.g., storms to sea level rise). Past work at Fire Island and elsewhere has demonstrated a link between inner shelf sediment availability and barrier island evolution over geologic and historical time scales. However, there have been few opportunities to explore nearshore sediment...
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Natural Hazards, Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center
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Geology and Sediment Availability - Coastal System Change at Fire Island, New York

Sediment supply is a critical control on barrier island vulnerability and resilience over a variety of time scales (e.g., storms to sea level rise). Past work at Fire Island and elsewhere has demonstrated a link between inner shelf sediment availability and barrier island evolution over geologic and historical time scales. However, there have been few opportunities to explore nearshore sediment...
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Coastal Land-Cover and Feature Datasets Extracted from Landsat Satellite Imagery, Northern Chandeleur Islands, Louisiana

This data release serves as an archive of coastal land-cover and feature datasets derived from Landsat satellite imagery at the northern Chandeleur Islands, Louisiana. To minimize effects of tidal water-level variations, 75 cloud-free, low-water images acquired between 1984 and 2019 were analyzed. Water, bare earth (sand), vegetated, and intertidal land-cover classes were mapped from Hewes Point t
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Single-Beam Bathymetric Data Collected in 2004 and 2008 from the Mississippi River Delta Plain, Louisiana

This data release serves as an archive of single-beam bathymetric (SBB) data collected in July 2004 (Madison Bay study area; U.S. Geological Survey [USGS] Field Activity Number [FAN] 2004-303-FA) and August 2008 (Bully Camp, Point au Chien, Caminada, Fourchon, and Leeville study areas; USGS FAN 08SWL02) at six study areas in the Mississippi River Delta Plain (MRDP), Louisiana. Data were collected
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Archive of Sediment Data from Vibracores Collected in 2016 from Fire Island, New York

Researchers from the U.S. Geological Survey (USGS) conducted a long-term coastal morphologic-change study at Fire Island, New York, prior to and after Hurricane Sandy impacted the area in October 2012. The Fire Island Coastal Change project objectives include understanding the morphologic evolution of the barrier island system on a variety of time scales (months to centuries) and resolving storm-r
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Coastal Single-Beam Bathymetry Data Collected in 2017 from the Chenier Plain, Louisiana

As part of the Louisiana Coastal Protection and Restoration Authority's Barrier Island Comprehensive Monitoring Program, scientist from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted a nearshore single-beam bathymetry survey along the Chenier Plain, Louisiana from Marsh Island to Sabine Pass. The goal of the BICM program is to provide long-term data on
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Sediment Data for Samples Collected in 2015, 2016, and 2017 from Coastal Louisiana

This data release serves as an archive of sediment data collected in 2015, 2016, and 2017 from coastal Louisiana. In 2015 and 2016, sediment grab samples (N=874) were collected coast-wide along shore-perpendicular transects that included back-barrier, emergent (beach and barrier island), shoreface, and nearshore environments. Sample locations were selected to re-occupy as closely as possible locat
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Archive of Ground Penetrating Radar and Differential Global Positioning System Data Collected in April 2016 from Fire Island, New York

Researchers from the U.S. Geological Survey (USGS) conducted a long-term, coastal morphologic-change study at Fire Island, New York, prior to and after Hurricane Sandy impacted the area in October 2012. The Fire Island Coastal Change project objectives include understanding the morphologic evolution of the barrier island system on a variety of time scales (months to centuries) and resolving storm-
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Wetland-Change Data Derived from Landsat Imagery, Assateague Island to Metompkin Island, Maryland and Virginia, 1984 to 2015

This data release includes geospatial datasets that were created to analyze wetland changes along the Virginia and Maryland Atlantic coasts between 1984 and 2015 as part of the U.S. Geological Survey's (USGS) Barrier Island and Estuarine Wetland Physical Change Assessment. Wetland change was determined by assessing two metrics: wetland persistence and land-cover switching. Because seasonal water l
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Single-Beam Bathymetry Data Collected in 2015 Nearshore Dauphin Island, Alabama

Dauphin Island, Alabama is a barrier island located in the Northern Gulf of Mexico that supports local residences, tourism, commercial infrastructure, and the historical Fort Gaines. During the past decade, Dauphin Island has been impacted by several major hurricanes (Ivan, 2004; Katrina, 2005; Isaac, 2012). Storms, along with sea level rise, present a continued threat to island stability. State a
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Elevation Data Collected in 2010 from Sabine National Wildlife Refuge, Louisiana

This data release serves as an archive of elevation data collected in August 2010 from Sabine National Wildlife Refuge (SNWR), Louisiana. Point (xyz) elevations were collected from historically formed open-water bodies and the surrounding emergent marsh using a combination of stop-and-go (semi-kinematic) and kinematic differential Global Positioning System (DGPS) surveying techniques. These data w
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Archive of Sediment Data Collected in 2014 and 2015 From Around Breton and Gosier Islands, Breton National Wildlife Refuge, Louisiana

Breton Island, located at the southern end of the Chandeleur Islands, supports one of Louisiana's largest historical brown pelican nesting colonies. Although the brown pelican (Pelecanus occidentalis) was delisted as an endangered species in 2009, nesting areas are threatened by continued land loss and are extremely vulnerable to storm impacts. The U.S. Fish and Wildlife Service proposed to restor
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Land area change in coastal Louisiana: A multidecadal perspective (from 1956 to 2006)

The U.S. Geological Survey (USGS) analyzed changes in the configuration of land and water in coastal Louisiana by using a sequential series of 14 data sets summarizing land and water areas from 1956 to 2006. The purpose of this study is to provide a spatially and temporally consistent source of quantitative information on land area across coastal Louisiana, broken into three physiographic province
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Documenting the multiple facets of a subsiding landscape from coastal cities and wetlands to the continental shelf

Land subsidence is a settling, sinking, or collapse of the land surface. In the southeastern United States, subsidence is frequently observed as sinkhole collapse in karst environments, wetland degradation and loss in coastal and other low-lying areas, and inundation of coastal urban communities. Human activities such as fluid extraction, mining, and overburden alteration can cause or exacerbate s
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Natural Hazards, Water Resources, Coastal and Marine Hazards and Resources Program, Caribbean-Florida Water Science Center (CFWSC), Lower Mississippi-Gulf Water Science Center, Ohio-Kentucky-Indiana Water Science Center, South Atlantic Water Science Center (SAWSC), St. Petersburg Coastal and Marine Science Center

Chandeleur Islands to Breton Island bathymetric and topographic datasets and operational sediment budget development: Methodology and analysis report

This study is part of the Coastal Protection and Restoration Authority (CPRA) Louisiana Barrier Island Comprehensive Monitoring (BICM) program. The goal of the BICM program is to provide long-term data on the barrier islands of Louisiana for monitoring change and assisting in coastal management. The BICM program uses historical data and acquires new data to map and monitor shoreline position, sedi
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Chenier Plain region bathymetric and topographic datasets: Methodology report

The goal of the Louisiana Barrier Island Comprehensive Monitoring (BICM) program is to provide long-term data on coastal Louisiana for monitoring change and assisting in coastal management. This study (carried out under Coastal Protection and Restoration Authority contract number 2000339324, BICM2—Chenier TopoBathy DEM) builds upon the previous BICM physical assessment of the Chenier Plain region
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Satellite-derived barrier response and recovery following natural and anthropogenic perturbations, northern Chandeleur Islands, Louisiana

The magnitude and frequency of storm events, relative sea-level rise (RSLR), sediment supply, and anthropogenic alterations drive the morphologic evolution of barrier island systems, although the relative importance of any one driver will vary with the spatial and temporal scales considered. To explore the relative contributions of storms and human alterations to sediment supply on de-cadal change
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Louisiana Coastal Zone sediment characterization; comparison of sediment grain sizes for samples collected in 2008 and 2015–2016 from the western Chenier plain to the Chandeleur Islands, Louisiana—Louisiana Barrier Island Comprehensive Monitoring (BICM) P

Repeated sampling and grain-size analysis of surficial sediments along the sandy shorelines of Louisiana is necessary to characterize coastal-zone sediment properties and evaluate sediment transport patterns within the nearshore environments. In 2008, and again in 2015 and 2016, sediment grab samples were collected along the shorelines of the western Chenier plain, the Isles Dernieres (Raccoon, Wh
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Application of sediment end-member analysis for understanding sediment fluxes, northern Chandeleur Islands, Louisiana

We analyzed grain-size distributions (GSDs) from a time-series of sediment samples to evaluate sediment transport following anthropogenic sand-berm emplacement at the northern Chandeleur Islands, Louisiana. End-member analysis (EMA) was applied to compare the end-member (EM) GSD of a known sediment source to GSDs from surrounding environments and characterize the physical redistribution of source
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Sediment data from vibracores collected in 2016 from Fire Island, New York

Researchers from the U.S. Geological Survey (USGS) conducted a long-term coastal morphologic-change study at Fire Island, New York, prior to and after Hurricane Sandy impacted the area in October 2012. The Fire Island Coastal Change project objectives include understanding the morphologic evolution of the barrier island system on a variety of time scales (months to centuries) and resolving storm-r
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Analysis of multi-decadal wetland changes, and cumulative impact of multiple storms 1984 to 2017

Land-cover classification analysis using Landsat satellite imagery acquired between 1984 and 2017 quantified short- (post-Hurricane Sandy) and long-term wetland-change trends along the Maryland and Virginia coasts between Metompkin Bay, VA and Ocean City, MD. Although there are limited options for upland migration of wetlands in the study area, regression analysis showed that wetland area increase
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Nearshore single-beam bathymetry data collected in 2015, Dauphin Island, Alabama

Dauphin Island, Alabama, is a barrier island located in the northern Gulf of Mexico that supports local residences, tourism, commercial infrastructure, and historic Fort Gaines. During the past decade, Dauphin Island was affected by several major hurricanes—Hurricanes Ivan (2004), Katrina (2005), and Isaac (2012)—and storms, along with sea-level rise, continue to present a threat to island stabili
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

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 along the New Jersey coast on October 29, 2012, impa
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Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Ground penetrating radar and differential global positioning system data collected in April 2016 from Fire Island, New York

Researchers from the U.S. Geological Survey (USGS) conducted a long-term coastal morphologic-change study at Fire Island, New York, prior to and after Hurricane Sandy impacted the area in October 2012. The Fire Island Coastal Change project objectives include understanding the morphologic evolution of the barrier island system on a variety of time scales (months to centuries) and resolving storm-r
By
Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center

Sediment data collected in 2014 and 2015 from around Breton and Gosier Islands, Breton National Wildlife Refuge, Louisiana

Breton Island, located at the southern end of the Chandeleur Islands, supports one of Louisiana’s largest historical brown pelican (Pelecanus occidentalis) nesting colonies. Although the brown pelican was delisted as an endangered species in 2009, nesting areas are threatened by continued land loss and are extremely vulnerable to storm impacts. The U.S. Fish and Wildlife Service proposed to restor
By
Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center
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SPCMSC scientists publish paper documenting recent historical evolution of the northern Chandeleur Islands, Louisiana

SPCMSC geologist Julie Bernier, with co-authors Jennifer Miselis and Nathaniel Plant, published a paper, "Satellite-Derived Barrier Response and...

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SPCMSC scientist interviewed for story about using Landsat to study coastal wetlands

SPCMSC geologist Julie Bernier was interviewed for an outreach story, "Keeping an Eye on Vulnerable Coastal...

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SPCMSC scientists to present at the State of the Coast 2021 conference

SPCMSC geologists are giving presentations on research of recent geomorphologic changes at the Chandeleur Islands, Louisiana, at the virtual State of...

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Geologist Julie Bernier presents findings from the Gulf Coast Subsidence Project at the Louisiana Coastal Neotectonics Workshop

SPCMSC geologist Julie Bernier was invited to present findings from the Gulf Coast Subsidence Project at the Louisiana Coastal Neotectonics workshop...

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SPCMSC scientists to present at Coastal Sediments '19 conference

SPCMSC scientists Julie Bernier, Noreen Buster, Kara Doran, Karen Morgan, and Tim Nelson will present their research at the Coastal Sediments '19...

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USGS scientists publish study documenting recent wetland-changes along Maryland and Virginia coastline

New study analyzed Landsat satellite imagery to document historical and recent (post-Hurricane Sandy) wetland changes that occurred along the Maryland...

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Julie Bernier to serve as panelist at the 2018 State of the Coast Conference

Julie Bernier (SPCMSC geologist) was invited to serve as a panelist for the session "Extraction Related Subsidence and the Potential for Uplift" at...

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Text, "Secrets of the Sediment on Barrier Islands" St. Pete Coastal/Marine Science Center" over photo of hand holding sand link
Text, "Secrets of the Sediment on Barrier Islands" St. Pete Coastal/Marine Science Center" over photo of hand holding sand link

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