{
    "tag": 6571,
    "title": "Digital elevation model (DEM) of south San Francisco Bay, California, created using bathymetry data collected between 2005 and 2020 (MLLW)",
    "pubdate": "20210708",
    "sername": null,
    "series_name": null,
    "issue": "DOI:10.5066\/P9TJTS8M",
    "publish": null,
    "publisher_name": null,
    "onlink": "https:\/\/cmgds.marine.usgs.gov\/catalog\/pcmsc\/DataReleases\/ScienceBase\/DR_P9TJTS8M\/SouthSFBay_DEM_Mosaic_MLLW_1m_metadata.faq.html",
    "format": null,
    "email": null,
    "descript": "A 1-m resolution, continuous surface, bathymetric digital elevation model (DEM) of the southern portion of San Francisco Bay, was constructed from bathymetric surveys collected from 2005 to 2020. In 2014 and 2015 the California Ocean Protection Council (OPC) contracted the collection of bathymetric surveys of large portions of San Francisco Bay. A total of 93 surveys were collected using a combination of multibeam and interferometric side-scan sonar systems. Of those 93 surveys, 75 consist of swaths of data ranging from 18- to just over 100-meters wide. These swaths were separated by data gaps ranging from 10- to just over 300-meters wide. The no-data areas required interpolation to create a continuous surface. The OPC surveys were combined with additional datasets collected by the United States Geological Survey (USGS), National Oceanic and Atmospheric Administration (NOAA), NOAA National Ocean Service (NOS), and the United States Army Corps of Engineers (USACE) to create a continuous, high-resolution digital elevation model (DEM). The creation of this DEM refines techniques developed by the USGS to create DEMs from historic bathymetric data, and allow for the creation of a modern-day bathymetric surface that can be compared to earlier surveys to delineate regions of sediment erosion and deposition.",
    "lang": null,
    "journal": null,
    "pwid": null,
    "originator": [
        {
            "name": "Fregoso, Theresa A.",
            "role": "Author"
        },
        {
            "name": "Jaffe, Bruce E.",
            "role": "Author"
        },
        {
            "name": "Foxgrover, Amy C.",
            "role": "Author"
        }
    ],
    "index_term": [
        {
            "thcode": 2,
            "code": "80",
            "name": "bathymetry",
            "scope": "The elevation of the earth's surface beneath a body of water, especially the ocean, typically determined by measurements of depth from the water surface."
        },
        {
            "thcode": 2,
            "code": "2041",
            "name": "digital elevation models",
            "scope": "Gridded elevation, geographically referenced to the surface of the earth, as digital data"
        },
        {
            "thcode": 2,
            "code": "445",
            "name": "geographic information systems",
            "scope": "Computer software that allows geospatially referenced data to be linked to geographic features. Use this term only for information that is about GIS and not for the use of GIS in applications and projects."
        },
        {
            "thcode": 2,
            "code": "474",
            "name": "geospatial datasets",
            "scope": "Collections of related digital information that are geographically referenced."
        },
        {
            "thcode": 2,
            "code": "492",
            "name": "GPS measurement",
            "scope": "Determination of distance and location using instruments receiving signals from the Global Positioning System, a system of satellites for identifying earth locations."
        },
        {
            "thcode": 2,
            "code": "2036",
            "name": "multibeam sonar",
            "scope": "Acoustic technique for determining depths or creating backscatter imagery in a wide swath of seafloor or lakebed centered below the instrument platform."
        },
        {
            "thcode": 2,
            "code": "2035",
            "name": "single-beam echo sounder",
            "scope": "Acoustic technique for determining seafloor or lakebed depth directly below the instrument platform."
        },
        {
            "thcode": 2,
            "code": "1176",
            "name": "topography",
            "scope": "Configuration of the land surface and sea floor."
        },
        {
            "thcode": 15,
            "code": "006",
            "name": "elevation",
            "scope": "Height above or below sea level, for example altitude, bathymetry, digital elevation models, slope, derived products, DEMs, TINs"
        },
        {
            "thcode": 15,
            "code": "012",
            "name": "inlandWaters",
            "scope": "Inland water features, drainage systems and characteristics, for example rivers and glaciers, salt lakes, water utilization plans, dams, currents, floods and flood hazards, water quality, hydrographic charts, watersheds, wetlands, hydrography"
        },
        {
            "thcode": 23,
            "code": "22",
            "name": "Bathymetry and Elevation",
            "scope": "Includes measures of the height of a location above or below a reference surface. Bathymetry is the elevation of the Earth's surface beneath a body of water, especially the ocean, typically determined by measurements of depth from the water surface at mean lower low water. Distributions are topographic maps and bathymetric charts based on collected data and also include smoothed or gridded maps of bathymetry and elevation from observational data or other associated factors. Assessment data types include models of ecological value, economic value, or current rates of alterations due to erosion, accretion, climate change, and other stressors (for example, wetland habitat loss). Predictions are the results of models or projections of future distributions, values, or ecological impacts of bathymetry, including predicted changes due to natural and human forces such as erosion, deposition, sea-level rise, and dredging activities; predictions also include the results of scenario-based models of bathymetry changes under different management strategies."
        },
        {
            "thcode": 61,
            "code": "707",
            "name": "geographic information systems (GIS)",
            "scope": "geographic subdiscipline that employs computer systems to manage, analyze, and display spatial information."
        },
        {
            "thcode": 61,
            "code": "417",
            "name": "Global Positioning System (GPS) observations",
            "scope": "the use of satellite signals from the Global Positioning System to determine the precise location of a terrestrial receiver."
        },
        {
            "thcode": 61,
            "code": "402",
            "name": "multibeam echo sounder",
            "scope": "acoustic technique for determining sea-floor depths in a wide swath centered below the instrument platform."
        },
        {
            "thcode": 61,
            "code": "404",
            "name": "single-beam echo sounder",
            "scope": "acoustic technique for determining sea-floor depth directly below the instrument platform."
        },
        {
            "thcode": 61,
            "code": "429",
            "name": "topographic mapping",
            "scope": "used for traditional cartographic methods that document the distribution and elevation of geographic and hydrographic features (and usually cultural features and administrative boundaries)."
        }
    ],
    "place_term": [],
    "image": [
        {
            "name": "https:\/\/www.sciencebase.gov\/catalog\/file\/get\/607df116d34e8564d67e3ae6?name=SouthSFBay_DEM_Mosaic_MLLW_1m.jpg&allowOpen=true",
            "description": "Bathymetric map of the southern portion of San Francisco Bay (MLLW)."
        }
    ],
    "fan": [
        "2016-678-FA",
        "2019-614-FA",
        "S0111SF"
    ]
}
