San Francisco Bay Bathymetry Completed
USGS research vessel Parke Snavely
Collecting bathymetry in Alviso Slough, south San Francisco Bay, in 2011
Bathymetry of a dynamic tidal estuary, such as San Francisco Bay, provides the observable linkage between anthropogenic modifications of the landscape—such as evolving land use practices, flood control, and water diversions—and natural forces of climate-driven river flow, sea level change, tides, and wind. By examining our record of hydrographic surveys, spanning over 150 years, we can gain insights into the probable effect of future modification including efforts toward restoration.
In addition to historical change analysis, current bathymetry is critical for the calibration and interpretation of hydrodynamic and ecological models. Mass balance and sheer stress are driven by bathymetry—even ecological niches are influenced by bathymetry (depth, turbidity, particle size, light, turbulence, etc.).
Here, we provide information about the bathymetric data available for San Francisco Bay.
Methods
In the example sequence shown below, the first step in the preparation of regular grids displayed on this web site begins with irregular hydrographic survey data (soundings) that have been corrected to a common datum (1).
The National Oceanic and Atmospheric Administration (NOAA) is the primary resource for obtaining these original soundings. Other agencies, including the US Army Corps of Engineers, California Department of Water Resources, US Bureau of Reclamation, and the USGS, have contributed local studies. Once the soundings are in hand they are contoured, and shoreline and marsh perimeters are added and combined into a geographic information system (GIS) (2).
All data layers must be adjusted to a common horizontal and vertical datum and all depths must have the same orientation and units. At this point a grid can be generated.
Quality control is an iterative process, performed on the resulting grid by comparing it with the original soundings (3, 4).
Errors are computed, plotted and repaired when appropriate. Errors are usually a result of incorrect unit tags on the source data or digitizing mistakes, but some are due to gradients in bathymetry that cannot be resolved by a single grid cell.
The final grid (5) can be adjusted to a different tidal datum using an adjustment grid.
This grid is produced by assigning tide levels observed at shore stations to co-tidal lines from the TRIM-2D model (6, 7).
Geostatistics
Using this 100m grid cell representation of the Bay we can compute some primary geomorphic features of the basin--such as surface area and volume--for a given tidal datum, and compare these and other statistical properties in the sub-basins of San Francisco Bay.
Full Bay
TIDAL DATUM | VOLUME (Mm3) | SURFACE AREA (Mm2) | AVG. DEPTH VOL/AREA (m) |
MEDIAN DEPTH (m) |
MLLW | 7142 | 1138 | 6.3 | 2.8 |
MSL | 8446 | 1219 | 6.9 | 3.6 |
MHHW | 9570 | 1244 | 7.7 | 4.4 |
Properties based on the Mean Sea Level grid
PROPERTY | SOUTH BAY | CENTRAL BAY | SAN PABLO BAY | SUISUN BAY |
Area (Mm2) | 426.8 | 326.3 | 273.4 | 169.6 |
Volume (Mm3) | 1971 | 4388 | 1016 | 990 |
Average depth (m) | 4.6 | 13.4 | 3.7 | 5.8 |
Median depth (m) | 3.2 | 10.9 | 2.5 | 3.6 |
% Area < 5 m |
69 | 32 | 82 | 57 |
Bathymetry Change
As described in our METHODS section, a continuous surface representation of each bathymetric survey was created using Topogrid, an Arc/Info module that utilizes sounding and contour information to create a hydrodynamically correct surface. Input data was a combination of point soundings and hand-drawn depth contours (see table below). Once a bathymetric surface has been created for each hydrographic survey, the surfaces are adjusted to a common datum and we compute change or difference grids. These new ‘change’ surfaces identify areas of erosion and deposition.
Here is an example difference map of San Pablo Bay (1856-1887). During this period there was massive sediment accumulation related to hydraulic gold mining.
The data supporting historical change analysis is quite extensive. The following tables summarize the survey dates, digitized soundings, and contours used to produce the bathymetric surfaces and difference maps for San Francisco Bay.
SUISUN BAY | ||
SURVEY YEAR | NUMBER OF SOUNDINGS | CONTOUR INTERVALS (ft) |
1867 | 18,202 | -4, 0, 6, 12, 18, 30, 60, 90 |
1887 | 21,753 | -4, 0, 6, 12, 18, 30, 60, 90 |
1922 | 17,303 | -4, 0, 6, 12, 18, 30, 60, 90 |
1942 | 36,169 | -4, 0, 6, 12, 18, 30, 60, 90 |
1990 | 93,393 | -1, 2, 5, 10, 15, 20, 25, 30, 35, 45 (meters) |
SAN PABLO BAY | ||
SURVEY YEAR | NUMBER OF SOUNDINGS | CONTOUR INTERVALS (ft) |
1856 | 4973 | 0, 2, 3, 4, 6, 12, 18, 24, 36, 42, 48, 60 |
1887 | 3679 | -1, 0, 1, 2, 3, 4, 5, 6, 7, 9, 12, 24, 30, 36, 48, 60 |
1898 | 1994 | 0, 3, 6, 12, 18, 24, 30, 36, 60 |
1922 | 42,764 | -1, 0, 1, 2, 3, 4, 5, 6, 12, 18, 30, 60 |
1951 | 62,900 | 0, 6, 12, 30, 48 |
1983 | 65,739 | 0, 6, 12, 18, 30, 36, 60 |
CENTRAL BAY | ||
SURVEY YEAR | NUMBER OF SOUNDINGS | CONTOUR INTERVALS (ft) |
1855 | 21,052 | 0, 6, 12, 18, 30, 60, 90, 120, 180, 240, 300 |
1895 | 289,282 | 0, 6, 12, 18, 30, 60, 90, 120, 180, 240, 300, 360 |
1920 | 48,116 | 0, 6, 12, 18, 30, 60, 90, 120 |
1947 | 229,551 | 0, 6, 12, 18, 30, 60, 90, 120, 180, 240, 300 |
1979 | 177,144 | 0, 6, 12, 18, 30, 60, 90, 120, 180, 240, 300, 360 |
SOUTH BAY | ||
SURVEY YEAR | NUMBER OF SOUNDINGS | CONTOUR INTERVALS (ft) |
1858 | 20,036 | 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70 |
1898 | 99,399 | 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70, 80 |
1931 | 92,451 | 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70, 80 |
1956 | 100,748 | 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70, 80 |
1983 | 136,095 | 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70, 80 |
2005 | ~2.7 million | 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70, 80 |
Official Publications
- San Pablo Bay Historical Analysis
USGS Open-File Report 98-759
Sedimentation and bathymetric change in San Pablo Bay, 1856-1983
- Suisun Bay Historical Analysis
USGS Open-File Report 99-563
Sedimentation and Bathymetry Changes in Suisun Bay: 1867-1990
- Central Bay Historical Analysis
USGS Open-File Report 2008-1312
Sediment Deposition, Erosion, and Bathymetric Change in Central San Francisco Bay: 1855–1979
- South Bay Historical Analysis Part 1
USGS Open-File Report 2004-1192
Deposition, Erosion, and Bathymetric Change in South San Francisco Bay: 1858-1983
- South Bay Historical Analysis Part 2
USGS Open-File Report 2006-1287
Sediment Deposition and Erosion in South San Francisco Bay, California from 1956 to 2005
Animations of change for North Bay
By linear interpolation, we can compute sedimentation maps for years between surveys and combine the maps to produce an animation of sedimentation for the North Bay. This animation gives an overall view of the system in time and space. We can see that, in the more active channels of Suisun Bay, surface sediment is deposited and erodes quickly in response to changing flows (floods/drought) and modifications (such as dredging the southern channel or long term mooring of the mothball fleet).
We assume:
- the sediment deposited in North San Francisco Bay between 1856 and 1887 was dominated by hydraulic mining debris;
- erosion observed in subsequent surveys was not re-deposited locally; and
- material deposited after 1887 was not mining debris.
Making these assumptions, we can predict the location and thickness of the original hydraulic mining debris. It is especially notable that the mercury employed in gold mining in the Sierra Nevada was refined liquid quicksilver or elemental mercury; this is a form of mercury much more likely to foster net methylation than is cinnabar, the form of mercury in most mercury mines. Approximately 10,000 tonnes of refined mercury were lost to the watershed during the Gold Rush mining era. Much of the mercury consumed by gold mining could have been incorporated into the 12 billion cubic meters of sediments extracted by the mining activities and released to the rivers of the Bay-Delta watershed. The mercury-laced hydraulic mining debris was ultimately transported to the bay-delta; it is known that large deposits of hydraulic mining debris remain in bay sediments. These wastes formed marshes, islands, or filled or diked marsh, or were deposited in shallow waters. Under the right circumstances this mercury contamination is transported through the food chain and concentrated in some commercial and sport fish. Human consumption of fish caught in the Bay is already restricted because of mercury contamination. Specifically, adults are advised to limit consumption of sport fish from the Bay to two times a month; pregnant or nursing women and children 6 or under should limit consumption to one time a month. Large shark and striped bass from the Bay should not be consumed at all. As we study the feasibility of restoration of marshes that were sinks for mining debris, the possibility of releasing mercury to the Bay must be considered.
Animations of mining debris deposition and subsequent erosion
Below are publications associated with this project.
Factors controlling floc settling velocity along a longitudinal estuarine transect
Influence of history and environment on the sediment dynamics of intertidal flats
Comparison of sediment supply to San Francisco Bay from watersheds draining the Bay Area and the Central Valley of California
Heavy mineral analysis for assessing the provenance of sandy sediment in the San Francisco Bay Coastal System
Distribution of biologic, anthropogenic, and volcanic constituents as a proxy for sediment transport in the San Francisco Bay Coastal System
Integration of bed characteristics, geochemical tracers, current measurements, and numerical modeling for assessing the provenance of beach sand in the San Francisco Bay Coastal System
Over 150 million m3 of sand-sized sediment has disappeared from the central region of the San Francisco Bay Coastal System during the last half century. This enormous loss may reflect numerous anthropogenic influences, such as watershed damming, bay-fill development, aggregate mining, and dredging. The reduction in Bay sediment also appears to be linked to a reduction in sediment supply and recent
Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 2009
Bathymetry and digital elevation models of Coyote Creek and Alviso Slough, South San Francisco Bay, California
Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 2008
Estuarine sedimentation, sediment character, and foraminiferal distribution in central San Francisco Bay, California
Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2007
Patterns and scales of phytoplankton variability in estuarine: Coastal ecosystems
Below are partners associated with this project.
- Overview
Bathymetry of a dynamic tidal estuary, such as San Francisco Bay, provides the observable linkage between anthropogenic modifications of the landscape—such as evolving land use practices, flood control, and water diversions—and natural forces of climate-driven river flow, sea level change, tides, and wind. By examining our record of hydrographic surveys, spanning over 150 years, we can gain insights into the probable effect of future modification including efforts toward restoration.
In addition to historical change analysis, current bathymetry is critical for the calibration and interpretation of hydrodynamic and ecological models. Mass balance and sheer stress are driven by bathymetry—even ecological niches are influenced by bathymetry (depth, turbidity, particle size, light, turbulence, etc.).
Here, we provide information about the bathymetric data available for San Francisco Bay.
Methods
Sources/Usage: Public Domain. View Media DetailsIn the example sequence shown below, the first step in the preparation of regular grids displayed on this web site begins with irregular hydrographic survey data (soundings) that have been corrected to a common datum (1).
The National Oceanic and Atmospheric Administration (NOAA) is the primary resource for obtaining these original soundings. Other agencies, including the US Army Corps of Engineers, California Department of Water Resources, US Bureau of Reclamation, and the USGS, have contributed local studies. Once the soundings are in hand they are contoured, and shoreline and marsh perimeters are added and combined into a geographic information system (GIS) (2).
All data layers must be adjusted to a common horizontal and vertical datum and all depths must have the same orientation and units. At this point a grid can be generated.
Quality control is an iterative process, performed on the resulting grid by comparing it with the original soundings (3, 4).
Errors are computed, plotted and repaired when appropriate. Errors are usually a result of incorrect unit tags on the source data or digitizing mistakes, but some are due to gradients in bathymetry that cannot be resolved by a single grid cell.
The final grid (5) can be adjusted to a different tidal datum using an adjustment grid.
This grid is produced by assigning tide levels observed at shore stations to co-tidal lines from the TRIM-2D model (6, 7).
Geostatistics
Using this 100m grid cell representation of the Bay we can compute some primary geomorphic features of the basin--such as surface area and volume--for a given tidal datum, and compare these and other statistical properties in the sub-basins of San Francisco Bay.
Sources/Usage: Public Domain. View Media DetailsSources/Usage: Public Domain. View Media DetailsFull Bay
TIDAL DATUM VOLUME (Mm3) SURFACE AREA (Mm2) AVG. DEPTH
VOL/AREA (m)MEDIAN DEPTH (m) MLLW 7142 1138 6.3 2.8 MSL 8446 1219 6.9 3.6 MHHW 9570 1244 7.7 4.4 Properties based on the Mean Sea Level grid
PROPERTY SOUTH BAY CENTRAL BAY SAN PABLO BAY SUISUN BAY Area (Mm2) 426.8 326.3 273.4 169.6 Volume (Mm3) 1971 4388 1016 990 Average depth (m) 4.6 13.4 3.7 5.8 Median depth (m) 3.2 10.9 2.5 3.6 % Area
< 5 m69 32 82 57 Bathymetry Change
As described in our METHODS section, a continuous surface representation of each bathymetric survey was created using Topogrid, an Arc/Info module that utilizes sounding and contour information to create a hydrodynamically correct surface. Input data was a combination of point soundings and hand-drawn depth contours (see table below). Once a bathymetric surface has been created for each hydrographic survey, the surfaces are adjusted to a common datum and we compute change or difference grids. These new ‘change’ surfaces identify areas of erosion and deposition.
Here is an example difference map of San Pablo Bay (1856-1887). During this period there was massive sediment accumulation related to hydraulic gold mining.
The data supporting historical change analysis is quite extensive. The following tables summarize the survey dates, digitized soundings, and contours used to produce the bathymetric surfaces and difference maps for San Francisco Bay.
SUISUN BAY SURVEY YEAR NUMBER OF SOUNDINGS CONTOUR INTERVALS (ft) 1867 18,202 -4, 0, 6, 12, 18, 30, 60, 90 1887 21,753 -4, 0, 6, 12, 18, 30, 60, 90 1922 17,303 -4, 0, 6, 12, 18, 30, 60, 90 1942 36,169 -4, 0, 6, 12, 18, 30, 60, 90 1990 93,393 -1, 2, 5, 10, 15, 20, 25, 30, 35, 45 (meters) SAN PABLO BAY SURVEY YEAR NUMBER OF SOUNDINGS CONTOUR INTERVALS (ft) 1856 4973 0, 2, 3, 4, 6, 12, 18, 24, 36, 42, 48, 60 1887 3679 -1, 0, 1, 2, 3, 4, 5, 6, 7, 9, 12, 24, 30, 36, 48, 60 1898 1994 0, 3, 6, 12, 18, 24, 30, 36, 60 1922 42,764 -1, 0, 1, 2, 3, 4, 5, 6, 12, 18, 30, 60 1951 62,900 0, 6, 12, 30, 48 1983 65,739 0, 6, 12, 18, 30, 36, 60 CENTRAL BAY SURVEY YEAR NUMBER OF SOUNDINGS CONTOUR INTERVALS (ft) 1855 21,052 0, 6, 12, 18, 30, 60, 90, 120, 180, 240, 300 1895 289,282 0, 6, 12, 18, 30, 60, 90, 120, 180, 240, 300, 360 1920 48,116 0, 6, 12, 18, 30, 60, 90, 120 1947 229,551 0, 6, 12, 18, 30, 60, 90, 120, 180, 240, 300 1979 177,144 0, 6, 12, 18, 30, 60, 90, 120, 180, 240, 300, 360 SOUTH BAY SURVEY YEAR NUMBER OF SOUNDINGS CONTOUR INTERVALS (ft) 1858 20,036 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70 1898 99,399 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70, 80 1931 92,451 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70, 80 1956 100,748 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70, 80 1983 136,095 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70, 80 2005 ~2.7 million 0, 3, 6, 12, 18, 24, 30, 36, 50, 60, 70, 80 Official Publications
- San Pablo Bay Historical Analysis
USGS Open-File Report 98-759
Sedimentation and bathymetric change in San Pablo Bay, 1856-1983
- Suisun Bay Historical Analysis
USGS Open-File Report 99-563
Sedimentation and Bathymetry Changes in Suisun Bay: 1867-1990
- Central Bay Historical Analysis
USGS Open-File Report 2008-1312
Sediment Deposition, Erosion, and Bathymetric Change in Central San Francisco Bay: 1855–1979
- South Bay Historical Analysis Part 1
USGS Open-File Report 2004-1192
Deposition, Erosion, and Bathymetric Change in South San Francisco Bay: 1858-1983
- South Bay Historical Analysis Part 2
USGS Open-File Report 2006-1287
Sediment Deposition and Erosion in South San Francisco Bay, California from 1956 to 2005
Animations of change for North Bay
Sources/Usage: Public Domain. View Media DetailsBy linear interpolation, we can compute sedimentation maps for years between surveys and combine the maps to produce an animation of sedimentation for the North Bay. This animation gives an overall view of the system in time and space. We can see that, in the more active channels of Suisun Bay, surface sediment is deposited and erodes quickly in response to changing flows (floods/drought) and modifications (such as dredging the southern channel or long term mooring of the mothball fleet).
We assume:
- the sediment deposited in North San Francisco Bay between 1856 and 1887 was dominated by hydraulic mining debris;
- erosion observed in subsequent surveys was not re-deposited locally; and
- material deposited after 1887 was not mining debris.
Making these assumptions, we can predict the location and thickness of the original hydraulic mining debris. It is especially notable that the mercury employed in gold mining in the Sierra Nevada was refined liquid quicksilver or elemental mercury; this is a form of mercury much more likely to foster net methylation than is cinnabar, the form of mercury in most mercury mines. Approximately 10,000 tonnes of refined mercury were lost to the watershed during the Gold Rush mining era. Much of the mercury consumed by gold mining could have been incorporated into the 12 billion cubic meters of sediments extracted by the mining activities and released to the rivers of the Bay-Delta watershed. The mercury-laced hydraulic mining debris was ultimately transported to the bay-delta; it is known that large deposits of hydraulic mining debris remain in bay sediments. These wastes formed marshes, islands, or filled or diked marsh, or were deposited in shallow waters. Under the right circumstances this mercury contamination is transported through the food chain and concentrated in some commercial and sport fish. Human consumption of fish caught in the Bay is already restricted because of mercury contamination. Specifically, adults are advised to limit consumption of sport fish from the Bay to two times a month; pregnant or nursing women and children 6 or under should limit consumption to one time a month. Large shark and striped bass from the Bay should not be consumed at all. As we study the feasibility of restoration of marshes that were sinks for mining debris, the possibility of releasing mercury to the Bay must be considered.
Animations of mining debris deposition and subsequent erosion
Sources/Usage: Public Domain. View Media DetailsSources/Usage: Public Domain. View Media Details - San Pablo Bay Historical Analysis
- Publications
Below are publications associated with this project.
Filter Total Items: 446Factors controlling floc settling velocity along a longitudinal estuarine transect
A 147 km longitudinal transect of flocculated cohesive sediment properties in San Francisco Bay (SFB) was conducted on June 17th, 2008. Our aim was to determine the factors that control floc settling velocity along the longitudinal axis of the estuary. The INSSEV-LF video system was used to measure floc diameters and settling velocities at 30 stations at a distance of 0.7 m above the estuary bed.AuthorsA.J. Manning, David H. SchoellhamerInfluence of history and environment on the sediment dynamics of intertidal flats
Morphological trends of three distinct intertidal environments in South San Francisco Bay were investigated using a combination of measurement and modeling tools. Because of the inherent relationship between the physical environment and the sediment properties, the sediment properties provide a good indicator of morphologic trends. A significant finding of this study is that surface sediment erodiAuthorsCraig A. Jones, Bruce E. JaffeComparison of sediment supply to San Francisco Bay from watersheds draining the Bay Area and the Central Valley of California
Quantifying suspended sediment loads is important for managing the world's estuaries in the context of navigation, pollutant transport, wetland restoration, and coastal erosion. To address these needs, a comprehensive analysis was completed on sediment supply to San Francisco Bay from fluvial sources. Suspended sediment, optical backscatter, velocity data near the head of the estuary, and dischargAuthorsL.J. McKee, M. Lewicki, David H. Schoellhamer, Neil K. GanjuHeavy mineral analysis for assessing the provenance of sandy sediment in the San Francisco Bay Coastal System
Heavy or high-specific gravity minerals make up a small but diagnostic component of sediment that is well suited for determining the provenance and distribution of sediment transported through estuarine and coastal systems worldwide. By this means, we see that surficial sand-sized sediment in the San Francisco Bay Coastal System comes primarily from the Sierra Nevada and associated terranes by wayAuthorsFlorence L. Wong, Donald L. Woodrow, Mary McGannDistribution of biologic, anthropogenic, and volcanic constituents as a proxy for sediment transport in the San Francisco Bay Coastal System
Although conventional sediment parameters (mean grain size, sorting, and skewness) and provenance have typically been used to infer sediment transport pathways, most freshwater, brackish, and marine environments are also characterized by abundant sediment constituents of biological, and possibly anthropogenic and volcanic, origin that can provide additional insight into local sedimentary processesAuthorsMary McGann, Li H. Erikson, Elmira Wan, Charles L. Powell, Rosalie F. MaddocksIntegration of bed characteristics, geochemical tracers, current measurements, and numerical modeling for assessing the provenance of beach sand in the San Francisco Bay Coastal System
Over 150 million m3 of sand-sized sediment has disappeared from the central region of the San Francisco Bay Coastal System during the last half century. This enormous loss may reflect numerous anthropogenic influences, such as watershed damming, bay-fill development, aggregate mining, and dredging. The reduction in Bay sediment also appears to be linked to a reduction in sediment supply and recent
AuthorsPatrick L. Barnard, Amy C. Foxgrover, Edwin P.L. Elias, Li H. Erikson, James R. Hein, Mary McGann, Kira Mizell, Robert J. Rosenbauer, Peter W. Swarzenski, Renee K. Takesue, Florence L. Wong, Don WoodrowSummary of suspended-sediment concentration data, San Francisco Bay, California, water year 2009
Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2009 (October 1, 2008–September 30, 2009). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, one site in San Pablo Bay, two sites in Central San Francisco Bay, and one site in South San Francisco Bay. Sensors werAuthorsPaul A. Buchanan, Tara L. MorganBathymetry and digital elevation models of Coyote Creek and Alviso Slough, South San Francisco Bay, California
In 2010, the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center completed three cruises to map the bathymetry of the main channel and shallow intertidal mudflats in the southernmost part of south San Francisco Bay. The three surveys were merged to generate comprehensive maps of Coyote Creek (from Calaveras Point east to the railroad bridge) and Alviso Slough (from the bay toAuthorsAmy C. Foxgrover, David P. Finlayson, Bruce E. Jaffe, Theresa A. FregosoSummary of suspended-sediment concentration data, San Francisco Bay, California, water year 2008
Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2008 (October 1, 2007–September 30, 2008). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, two sites in Central San Francisco Bay, and one site in South San Francisco Bay. Sensors were positioned at two depthsAuthorsPaul A. Buchanan, Tara L. MorganEstuarine sedimentation, sediment character, and foraminiferal distribution in central San Francisco Bay, California
Central San Francisco Bay is the deepest subembayment in the San Francisco Bay estuary and hence has the largest water volume of any of the subembayments. It also has the strongest tidal currents and the coarsest sediment within the estuary. Tidal currents are strongest over the west-central part of central bay and, correspondingly, this area is dominated by sand-size sediment. Much of the area eaAuthorsJohn L. Chin, Donald L. Woodrow, Mary McGann, Florence L. Wong, Theresa A. Fregoso, Bruce E. JaffeSummary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2007
Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2007 (October 1, 2006-September 30, 2007). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, two sites in Central San Francisco Bay, and one site in South San Francisco Bay. Sensors were positioned at two depthsAuthorsPaul A. Buchanan, Tara L. MorganPatterns and scales of phytoplankton variability in estuarine: Coastal ecosystems
Phytoplankton variability is a primary driver of chemical and biological dynamics in the coastal zone because it directly affects water quality, biogeochemical cycling of reactive elements, and food supply to consumer organisms. Much has been learned about patterns of phytoplankton variability within individual ecosystems, but patterns have not been compared across the diversity of ecosystem typesAuthorsJames E. Cloern, Alan D. Jassby - Partners
Below are partners associated with this project.