{
    "tag": 9975,
    "title": "Image showing bathymetry data for the coastal region of Rincon, Puerto Rico (rincon_lidar.tif)",
    "pubdate": "2007",
    "sername": null,
    "series_name": null,
    "issue": "2007-1017",
    "publish": null,
    "publisher_name": null,
    "onlink": "https:\/\/cmgds.marine.usgs.gov\/catalog\/whcmsc\/open_file_report\/ofr2007-1017\/rincon_lidar_meta.faq.html",
    "format": null,
    "email": null,
    "descript": "These data were collected by the SHOALS (Scanning Hydrographic Operational Airborne Lidar Survey) system which consists of an airborne laser transmitter\/receiver capable of measuring 400 soundings per second.  The system operates from a deHavilland DHC-6 Twin Otter flying at altitudes between 200 and 400 meters with a ground speed of about 100 knots.  The SHOALS system also includes a ground-based data processing system for calculating acurate horizontal position and water depth. Lidar is an acronym for LIght Detection And Ranging.  The system operates by emitting a pulse of light that travels from an airborne platform to the water surface where a small portion of the laser energy is backscattered to the airborne receiver.  The remaining energy at the water's surface propogates through the water column and reflects off the sea bottom and back to the airborne detector.  The time difference between the surface return and the bottom return corresponds to water depth.  The maximum depth the system is able to sense is related to the complex interaction of radiance of bottom material, incident sun angle and intensity, and the type and quantity of organics or sediments in the water column.  As a rule-of-thumb, the SHOALS system should be capable of sensing bottom to depths equal to two or three times the Secchi depth.",
    "lang": null,
    "journal": null,
    "pwid": null,
    "originator": [
        {
            "name": "U.S. Geological Survey",
            "role": "Author"
        },
        {
            "name": "Thieler, E. Robert",
            "role": "Author"
        },
        {
            "name": "Rodriguez, Rafael W.",
            "role": "Author"
        },
        {
            "name": "Himmelstoss, Emily A.",
            "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": "474",
            "name": "geospatial datasets",
            "scope": "Collections of related digital information that are geographically referenced."
        },
        {
            "thcode": 2,
            "code": "2046",
            "name": "image mosaics",
            "scope": "Composite images formed by overlapping existing images, typically arranged to achieve greater spatial coverage."
        },
        {
            "thcode": 2,
            "code": "648",
            "name": "lidar",
            "scope": "Light detection and ranging, an airborne, spaceborne or ground-based laser-ranging technique commonly used for acquiring high-resolution topographic data."
        },
        {
            "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": "010",
            "name": "imageryBaseMapsEarthCover",
            "scope": "Base maps, for example land\/earth cover, topographic maps, imagery, unclassified images, annotations, digital ortho imagery"
        },
        {
            "thcode": 15,
            "code": "014",
            "name": "oceans",
            "scope": "Features and characteristics of salt water bodies (excluding inland waters), for example tides, tidal waves, coastal information, reefs, maritime, outer continental shelf submerged lands, shoreline"
        }
    ],
    "place_term": [],
    "image": [],
    "fan": []
}