Jessie Lacy
Research Oceanographer with the USGS Pacific Coastal and Marine Science Center
My research interests include: Hydrodynamics of the coastal ocean, estuaries, and lakes; Lateral dynamics in estuaries with complex topography, and their influence on mixing; The dynamics of stratification and baroclinic transport; Estimation of bottom roughness, bottom shear stress, and sediment resuspension in wave-dominated environments; Interaction between aquatic vegetation and hydrodynamics
Science and Products
Filter Total Items: 14
Hydrodynamic and sediment transport data from San Pablo Bay (northern San Francisco Bay), 2011-2012
The U.S. Geological Survey Pacific Coastal and Marine Science Center collected data to investigate sediment dynamics in the shallows of San Pablo Bay in two deployments: February to March 2011 (ITX11) and May to June 2012 (ITX12). This data release includes time-series data and grain-size distributions from sediment grabs collected during the deployments. During each deployment, time series of cur
Hydrodynamic and sediment transport data from San Pablo Bay and China Camp marsh (northern San Francisco Bay), 2013-2016
The U.S. Geological Survey Pacific Coastal and Marine Science Center collected data to investigate sediment dynamics in the shallows of San Pablo Bay and sediment exchange between bay shallows and the tidal salt marsh in China Camp State Park in a series of deployments between December 2013 and June 2016. This data release includes two related groups of data sets. The first group, denoted by names
Filter Total Items: 40
Bed shear stress estimation under wave conditions using near-bottom measurements: Comparison of methods
Understanding the influence of waves on bed shear stress is critical for predicting morphodynamical behaviours in coastal areas. Near-bed flow was measured on the middle and lower intertidal mudflats along the Jiangsu coast, China, using a three-dimensional acoustic velocimeter that collected a 3.5-cm vertical profile at 1mm resolution and sample rate of 25 Hz. On the lower and middle tidal flats,
Authors
Qian Zhang, Zheng Gong, Changkuan Zhang, Jessica R. Lacy, Bruce E. Jaffe, Beibei Xu
The influence of neap-spring tidal variation and wave energy on sediment flux in salt marsh tidal creeks
Sediment flux in marsh tidal creeks is commonly used to gage sediment supply to marshes. We conducted a field investigation of temporal variability in sediment flux in tidal creeks in the accreting tidal marsh at China Camp State Park adjacent to northern San Francisco Bay. Suspended-sediment concentration (SSC), velocity, and depth were measured near the mouths of two tidal creeks during three
Authors
Jessica R. Lacy, Matthew C. Ferner, John C. Callaway
Three-dimensional modeling of fine sediment transport by waves and currents in a shallow estuary
A suspended sediment transport model is implemented in the unstructured‐grid SUNTANS model and applied to study fine‐grained sediment transport in South San Francisco Bay. The model enables calculation of suspension of bottom sediment based on combined forcing of tidal currents and wind waves. We show that accurate results can be obtained by employing two‐size classes which are representative of m
Authors
Yi-Ju Chou, Kurt S. Nelson, Rusty C. Holleman, Oliver B. Fringer, Mark T. Stacey, Jessica R. Lacy, Stephen G. Monismith, Jeffrey R. Koseff
Wave attenuation across a tidal marsh in San Francisco Bay
Wave attenuation is a central process in the mechanics of a healthy salt marsh. Understanding how wave attenuation varies with vegetation and hydrodynamic conditions informs models of other marsh processes that are a function of wave energy (e.g. sediment transport) and allows for the incorporation of marshes into coastal protection plans. Here, we examine the evolution of wave height across a tid
Authors
Madeline R. Foster-Martinez, Jessica R. Lacy, Matthew C. Ferner, Evan A. Variano
Bathymetric survey and digital elevation model of Little Holland Tract, Sacramento-San Joaquin Delta, California
The U.S. Geological Survey conducted a bathymetric survey in Little Holland Tract, a flooded agricultural tract, in the northern Sacramento-San Joaquin Delta (the “Delta”) during the summer of 2015. The new bathymetric data were combined with existing data to generate a digital elevation model (DEM) at 1-meter resolution. Little Holland Tract (LHT) was historically diked off for agricultural uses
Authors
Alexander G. Snyder, Jessica R. Lacy, Andrew W. Stevens, Emily M. Carlson
Wave attenuation in the shallows of San Francisco Bay
Waves propagating over broad, gently-sloped shallows decrease in height due to frictional dissipation at the bed. We quantified wave-height evolution across 7 km of mudflat in San Pablo Bay (northern San Francisco Bay), an environment where tidal mixing prevents the formation of fluid mud. Wave height was measured along a cross shore transect (elevation range−2mto+0.45mMLLW) in winter 2011 and sum
Authors
Jessica R. Lacy, Lissa J. MacVean
Mechanisms of sediment flux between shallows and marshes
We conducted a field study to investigate temporal variation and forcing mechanisms of sediment flux between a salt marsh and adjacent shallows in northern San Francisco Bay. Suspended-sediment concentration (SSC), tidal currents, and wave properties were measured over the marsh, in marsh creeks, and in bay shallows. Cumulative sediment flux in the marsh creeks was bayward during the study, and wa
Authors
Jessica R. Lacy, L.M. Schile, J.C. Callaway, M.C. Ferner
Model-based interpretation of sediment concentration and vertical flux measurements in a shallow estuarine environment
A one-dimensional numerical model describing tidally varying vertical mixing and settling was used to interpret sediment concentrations and vertical fluxes observed in the shoals of South San Francisco Bay by two acoustic Doppler velocimeters (ADVs) at elevations of 0.36 m and 0.72 m above bed. Measured sediment concentrations changed by up to 100 g m−3 over the semidiurnal tidal cycle. These dyna
Authors
Andreas Brand, Jessica R. Lacy, Steve Gladding, Rusty Holleman, Mark T. Stacey
Lateral baroclinic forcing enhances sediment transport from shallows to channel in an estuary
We investigate the dynamics governing exchange of sediment between estuarine shallows and the channel based on field measurements at eight stations spanning the interface between the channel and the extensive eastern shoals of South San Francisco Bay. The study site is characterized by longitudinally homogeneous bathymetry and a straight channel, with friction more important than the Coriolis forc
Authors
Jessica R. Lacy, Steve Gladding, Andreas Brand, Audric Collignon, Mark T. Stacey
Autonomous bed-sediment imaging-systems for revealing temporal variability of grain size
We describe a remotely operated video microscope system, designed to provide high-resolution images of seabed sediments. Two versions were developed, which differ in how they raise the camera from the seabed. The first used hydraulics and the second used the energy associated with wave orbital motion. Images were analyzed using automated frequency-domain methods, which following a rigorous partial
Authors
Daniel Buscombe, David M. Rubin, Jessica R. Lacy, Curt D. Storlazzi, Gerald Hatcher, Henry Chezar, Robert Wyland, Christopher R. Sherwood
Interactions between waves, sediment, and turbulence on a shallow estuarine mudflat
Measurements were collected on a shallow estuarine mudflat in northern San Francisco Bay to examine the physical processes controlling waves, turbulence, sediment resuspension, and their interactions. Tides alone forced weak to moderate currents of 10–30 cm s-1 in depths of 0–3 m, and maintained a background suspension of 30–50 mg L21 of fine sediment. In the presence of wind waves, bottom orbital
Authors
Lissa J. MacVean, Jessica R. Lacy
Currents, drag, and sediment transport induced by a tsunami
We report observations of water surface elevation, currents, and suspended sediment concentration (SSC) from a 10-m deep site on the inner shelf in northern Monterey Bay during the arrival of the 2010 Chile tsunami. Velocity profiles were measured from 3.5 m above the bed (mab) to the surface at 2 min intervals, and from 0.1 to 0.7 mab at 1 Hz. SSC was determined from the acoustic backscatter of t
Authors
Jessica R. Lacy, David M. Rubin, Daniel Buscombe
Science and Products
Filter Total Items: 14
Hydrodynamic and sediment transport data from San Pablo Bay (northern San Francisco Bay), 2011-2012
The U.S. Geological Survey Pacific Coastal and Marine Science Center collected data to investigate sediment dynamics in the shallows of San Pablo Bay in two deployments: February to March 2011 (ITX11) and May to June 2012 (ITX12). This data release includes time-series data and grain-size distributions from sediment grabs collected during the deployments. During each deployment, time series of cur
Hydrodynamic and sediment transport data from San Pablo Bay and China Camp marsh (northern San Francisco Bay), 2013-2016
The U.S. Geological Survey Pacific Coastal and Marine Science Center collected data to investigate sediment dynamics in the shallows of San Pablo Bay and sediment exchange between bay shallows and the tidal salt marsh in China Camp State Park in a series of deployments between December 2013 and June 2016. This data release includes two related groups of data sets. The first group, denoted by names
Filter Total Items: 40
Bed shear stress estimation under wave conditions using near-bottom measurements: Comparison of methods
Understanding the influence of waves on bed shear stress is critical for predicting morphodynamical behaviours in coastal areas. Near-bed flow was measured on the middle and lower intertidal mudflats along the Jiangsu coast, China, using a three-dimensional acoustic velocimeter that collected a 3.5-cm vertical profile at 1mm resolution and sample rate of 25 Hz. On the lower and middle tidal flats,
Authors
Qian Zhang, Zheng Gong, Changkuan Zhang, Jessica R. Lacy, Bruce E. Jaffe, Beibei Xu
The influence of neap-spring tidal variation and wave energy on sediment flux in salt marsh tidal creeks
Sediment flux in marsh tidal creeks is commonly used to gage sediment supply to marshes. We conducted a field investigation of temporal variability in sediment flux in tidal creeks in the accreting tidal marsh at China Camp State Park adjacent to northern San Francisco Bay. Suspended-sediment concentration (SSC), velocity, and depth were measured near the mouths of two tidal creeks during three
Authors
Jessica R. Lacy, Matthew C. Ferner, John C. Callaway
Three-dimensional modeling of fine sediment transport by waves and currents in a shallow estuary
A suspended sediment transport model is implemented in the unstructured‐grid SUNTANS model and applied to study fine‐grained sediment transport in South San Francisco Bay. The model enables calculation of suspension of bottom sediment based on combined forcing of tidal currents and wind waves. We show that accurate results can be obtained by employing two‐size classes which are representative of m
Authors
Yi-Ju Chou, Kurt S. Nelson, Rusty C. Holleman, Oliver B. Fringer, Mark T. Stacey, Jessica R. Lacy, Stephen G. Monismith, Jeffrey R. Koseff
Wave attenuation across a tidal marsh in San Francisco Bay
Wave attenuation is a central process in the mechanics of a healthy salt marsh. Understanding how wave attenuation varies with vegetation and hydrodynamic conditions informs models of other marsh processes that are a function of wave energy (e.g. sediment transport) and allows for the incorporation of marshes into coastal protection plans. Here, we examine the evolution of wave height across a tid
Authors
Madeline R. Foster-Martinez, Jessica R. Lacy, Matthew C. Ferner, Evan A. Variano
Bathymetric survey and digital elevation model of Little Holland Tract, Sacramento-San Joaquin Delta, California
The U.S. Geological Survey conducted a bathymetric survey in Little Holland Tract, a flooded agricultural tract, in the northern Sacramento-San Joaquin Delta (the “Delta”) during the summer of 2015. The new bathymetric data were combined with existing data to generate a digital elevation model (DEM) at 1-meter resolution. Little Holland Tract (LHT) was historically diked off for agricultural uses
Authors
Alexander G. Snyder, Jessica R. Lacy, Andrew W. Stevens, Emily M. Carlson
Wave attenuation in the shallows of San Francisco Bay
Waves propagating over broad, gently-sloped shallows decrease in height due to frictional dissipation at the bed. We quantified wave-height evolution across 7 km of mudflat in San Pablo Bay (northern San Francisco Bay), an environment where tidal mixing prevents the formation of fluid mud. Wave height was measured along a cross shore transect (elevation range−2mto+0.45mMLLW) in winter 2011 and sum
Authors
Jessica R. Lacy, Lissa J. MacVean
Mechanisms of sediment flux between shallows and marshes
We conducted a field study to investigate temporal variation and forcing mechanisms of sediment flux between a salt marsh and adjacent shallows in northern San Francisco Bay. Suspended-sediment concentration (SSC), tidal currents, and wave properties were measured over the marsh, in marsh creeks, and in bay shallows. Cumulative sediment flux in the marsh creeks was bayward during the study, and wa
Authors
Jessica R. Lacy, L.M. Schile, J.C. Callaway, M.C. Ferner
Model-based interpretation of sediment concentration and vertical flux measurements in a shallow estuarine environment
A one-dimensional numerical model describing tidally varying vertical mixing and settling was used to interpret sediment concentrations and vertical fluxes observed in the shoals of South San Francisco Bay by two acoustic Doppler velocimeters (ADVs) at elevations of 0.36 m and 0.72 m above bed. Measured sediment concentrations changed by up to 100 g m−3 over the semidiurnal tidal cycle. These dyna
Authors
Andreas Brand, Jessica R. Lacy, Steve Gladding, Rusty Holleman, Mark T. Stacey
Lateral baroclinic forcing enhances sediment transport from shallows to channel in an estuary
We investigate the dynamics governing exchange of sediment between estuarine shallows and the channel based on field measurements at eight stations spanning the interface between the channel and the extensive eastern shoals of South San Francisco Bay. The study site is characterized by longitudinally homogeneous bathymetry and a straight channel, with friction more important than the Coriolis forc
Authors
Jessica R. Lacy, Steve Gladding, Andreas Brand, Audric Collignon, Mark T. Stacey
Autonomous bed-sediment imaging-systems for revealing temporal variability of grain size
We describe a remotely operated video microscope system, designed to provide high-resolution images of seabed sediments. Two versions were developed, which differ in how they raise the camera from the seabed. The first used hydraulics and the second used the energy associated with wave orbital motion. Images were analyzed using automated frequency-domain methods, which following a rigorous partial
Authors
Daniel Buscombe, David M. Rubin, Jessica R. Lacy, Curt D. Storlazzi, Gerald Hatcher, Henry Chezar, Robert Wyland, Christopher R. Sherwood
Interactions between waves, sediment, and turbulence on a shallow estuarine mudflat
Measurements were collected on a shallow estuarine mudflat in northern San Francisco Bay to examine the physical processes controlling waves, turbulence, sediment resuspension, and their interactions. Tides alone forced weak to moderate currents of 10–30 cm s-1 in depths of 0–3 m, and maintained a background suspension of 30–50 mg L21 of fine sediment. In the presence of wind waves, bottom orbital
Authors
Lissa J. MacVean, Jessica R. Lacy
Currents, drag, and sediment transport induced by a tsunami
We report observations of water surface elevation, currents, and suspended sediment concentration (SSC) from a 10-m deep site on the inner shelf in northern Monterey Bay during the arrival of the 2010 Chile tsunami. Velocity profiles were measured from 3.5 m above the bed (mab) to the surface at 2 min intervals, and from 0.1 to 0.7 mab at 1 Hz. SSC was determined from the acoustic backscatter of t
Authors
Jessica R. Lacy, David M. Rubin, Daniel Buscombe