| Bogue Sound, NC (S030) Bathymetric Digital Elevation Model (30 meter resolution) Derived
From Source Hydrographic Survey Soundings Collected by NOAA |
| Bathymetry for Bogue Sound was derived from eleven surveys containing 52,366 soundings.
Two older, overlapping, less accurate surveys were entirely omitted. The overlap from
one older, less accurate survey was omitted before tinning the data. The average separation
between soundings was 72 meters. Surveys dating from 1876 to 1953 covered the east
and west portions of the sound. Surveys from 1974 covered the center portion of the
sound. The total range of sounding data was 0.9 to -17.1 meters at mean low water.
Mean high water values between 0.5 to 1.0 meters were assigned to the shoreline. One
point that was not consistent with the surrounding data was removed prior to tinning.
DEM grid values outside the shoreline (on land) were assigned null values (-32676).
Bogue Sound has six 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. |
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