{
    "tag": 19298,
    "title": "Central San Francisco Bay bathymetric change: 1855 to 1979",
    "pubdate": "20241004",
    "sername": null,
    "series_name": null,
    "issue": "doi:10.5066\/P13H35QB",
    "publish": null,
    "publisher_name": null,
    "onlink": "https:\/\/cmgds.marine.usgs.gov\/catalog\/pcmsc\/DataReleases\/ScienceBase\/DR_P13H35QB\/CentralBay_BathyChange_metadata.faq.html",
    "format": null,
    "email": null,
    "descript": "This data release provides a series of four bathymetric change grids generated from historical bathymetric surveys collected in central San Francisco Bay, CA from the 1855 to 1979. The National Ocean Service (NOS) and its predecessor, the United States Coast and Geodetic Survey, collected hydrographic surveys in 1855, 1895, 1920, 1947, and 1979. Surface modeling software was used to generate bathymetric DEMs of each of these surveys. The bathymetric DEMs were then adjusted to account for gridding interpolation bias and changes in sea level through time. The adjusted DEMs for consecutive surveys were then differenced to reveal the amount of sediment erosion and deposition and changes from human activities (e.g., dredging, sand mining, and sediment placement) that occurred through time. These bathymetric change grids are provided here in GeoTIFF format with a horizontal resolution of 25 meters and can be used to quantify net sediment volume change and rates of change throughout the bay.",
    "lang": null,
    "journal": null,
    "pwid": null,
    "originator": [
        {
            "name": "Foxgrover, Amy C.",
            "role": "Author"
        },
        {
            "name": "Fregoso, Theresa A.",
            "role": "Author"
        },
        {
            "name": "Jaffe, Bruce E.",
            "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": "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": "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\/66760496d34e3cf50fef28ef?name=CB_chg_map_1855_1895.png&allowOpen=true",
            "description": "Sample map of central Bay bathymetric change from 1855 to 1895."
        }
    ],
    "fan": []
}