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Raritan Bay, NJ/NY (M060R) Bathymetric Digital Elevation Model (30 meter resolution) Derived From Source Hydrographic Survey Soundings Collected by NOAA
NEW - the following surveys were added because they represent more recent data than those formerly in the same geographic location. They are FE0239 (1979) and H07841 (1950). Bathymetry for Raritan Bay was derived from twenty- five surveys containing 230,575 soundings. Seventeen overlapping, older, less accurate surveys were entirely omitted, and the overlap from one older, less accurate survey was omitted before tinning the data. The average separation between soundings was 44 meters. The twenty-five surveys used dated from 1927 to 1988. The survey from 1927 was located in the southeast. The eight surveys from 1934 to 1936 were located in the extreme east and west. The remaining surveys dated from 1950 to 1988. The total range of sounding data was 1.9 meters to - 33.7 meters at mean low water. Mean high water values between 0.8 and 1.8 meters were assigned to the shoreline. Sixteen points were found that were not consistent with the surrounding data. These were removed prior to tinning. DEM grid values outside the shoreline (on land) were assigned null values (-32676). Raritan Bay has seventeen 7.5 minute DEMs and two one degree DEMs. The 1 degree DEMs were generated from the higher resolution 7.5 minute DEMs which covered the estuary. A Digital Elevation Model (DEM) contains a series of elevations ordered from south to north with the order of the columns from west to east. The DEM is formatted as one ASCII header record (A- record), followed by a series of profile records (B- records) each of which include a short B-record header followed by a series of ASCII integer elevations (typically in units of 1 centimeter) per each profile. The last physical record of the DEM is an accuracy record (C-record). The 7.5-minute DEM (30- by 30-m data spacing) is cast on the Universal Transverse Mercator (UTM) projection. It provides coverage in 7.5- by 7.5-minute blocks. Each product provides the same coverage as a standard USGS 7.5-minute quadrangle but the DEM contains over edge data. Coverage is available for many estuaries of the contiguous United States but is not complete.