FLORIDA GEOGRAPHIC DATA LIBRARY DOCUMENTATION
VERSION 2006
TITLE: BATHYMETRIC CONTOURS FOR THE STATE OF FLORIDA AND SURROUNDING AREAS
Geodataset Name: BATHYM Geodataset Type: SHAPE Geodataset Feature: LINE
GENERAL DESCRIPTION:
This dataset contains bathymetric contours surrounding Florida and parts of Georgia with increasing resolution in coastal areas.
DATA SOURCE(S): NOAA Coastal Services Center
SCALE OF ORIGINAL SOURCE MAPS: Variable
DATE OF AUTOMATION OR SOURCE: 2000
GEODATASET EXTENT: State of Florida
FEATURE ATTRIBUTE TABLES:
Datafile Name: FLBATHY.DBF ITEM NAME WIDTH TYPE PRECISION SHAPE 9 SHAPELINE 0 DATASET 8 CHARACTER 0 SOURCE 8 CHARACTER 0 RES 5 CHARACTER 0 DEPTH_FT 17 DECIMAL 1 DEPTH_M 17 DECIMAL 1 DEPTH_FA 17 DECIMAL 1 DESCRIPT 50 CHARACTER -
FEATURE ATTRIBUTE TABLES CODES AND VALUES:
ITEM ITEM DESCRIPTION
SHAPE Data attribute inherent to the ESRI shapefile format,
which defines the data as a point, polyline, or polygon.
DATASET Descriptors categorizing arcs by different source data and
processing methods
DEEP = Used DBDB_V- 5min resolution dataset (see SOURCE item)
Data was obtained on-line as an ascii xyz file and
converted into dbf4 format. Imported into ArcView and
converted into a point theme of 5 min resolution. A land
mask was defined out to 10 km seaward of the coastline,
and a seed grid of zero values applied to masked regions.
The resulting point coverage was converted to a grid using
IDW (12 neares neighbors, power 2, cellsize 5 min). The
interpolated grid was contoured twice at 200 and 10 meter
intervals. 200 meter contours were used in regions deeper
than 200 meters and 10 meter contours applied to areas where
no other shelf data was available.
E_COAST = Used NGDC dataset (see SOURCE item)
Data was extracted from the CD ROM for the coverage area in
22 , 1 degree ascii grids of 3 arc-second resolution. Grids
were converted to ArcView grid themes using the ArcView import
utility. Grids were mosaiced into a single 3-arc second grid
theme. The grid was contoured at 2 meter intervals, and all
countours deeper than 10 meters deleted from the attribute table.
E_SHELF = Used NGDC dataset (see SOURCE item)
NGDC Data was extracted from the CD ROM for the coverage area
in 22 , 1 degree ascii grids of 3 arc-second resolution. Grids
were converted to ArcView grid themes using the ArcView import
utility. Grids were mosaiced into a single 30-arc second grid
theme. The grid was contoured at 10 meter intervals, and all
countours shallower than 10 meters deleted from the attribute
table.
FL_COAST = Used GEONEX dataset (see SOURCE item)
Data was obtained as an arc vector coverage. The coverage was
origionally projected in the coordinate system:
Base projection: Albers Cent. merid. -84 Cent. parallel: 24
std. parallel1: 24 std. parallel2: 31.5 Datum: grs 80 unit: meter
The coverage projection was changed to grs80, geographic,
decimal degrees using the ArcView projection utility. Contour
depth units were converted from feet to meters and all special
nondepth contours eliminated. All contours deeper than 10 meters
were also eliminated.
FL_SHELF = Used DBDB_V - 30sec resolution
Data was obtained from the website as lat-long-depth ascii files.
The files were imported converted to DBF4 format and imported as
tables in ArcView. The tables were converted into point themes and
merged to provide complete coverage of the region. The merged
point theme was converted into a grid theme via IDW interpolation
(12 nearest neighbors, power 2, cellsize 30 sec). The grid was
contoured at 10 m intervals. All contours deeper than 200 meters
were eliminated. Several arcs were added by hand to connect
contours to the e_shelf contours. These can be identified by the
source attribute "edit".
SOURCE Categorizes arcs by source data
NGDC = National Geophysical Data Center Coastal Relief Model
DBDB_V = Digital Bathymetric Data Base
GEONEX = GEONEX Florida Coastal Contours
EDIT = Arcs added by hand to connect fl_shelf contours to e_shelf contours.
RES Defines maximum horizontal resolution of source data
DEPTH_FT Depth in feet
DEPTH_M Depth in meters
DEPTH_FA Depth in fathoms
DESCRIPT FGDL added item based on DATASET
USER NOTES:
These data are based on interpretation of available information and should not be construed as legally binding. These data should not be used for navigation. Florida regional bathymetric contours consist of a shapefile of bathymetric contours with increasing resolution in coastal areas. Contours were derived from a composite of several bathymetric datasets of varying regional coverage and resolution. The various input datasets and processing methods used to create this dataset are listed under the "SOURCE" and "DATASET" items. Online listing for the National Geophysical Data Center Coastal Relief is: http://www.ngdc.noaa.gov/mgg/coastal Online listing for the Digital Bathymetric Data Base is: http://128.160.23.42/dbdbv/dbdbv.html Isobath intervals range from 2 meter in coastal areas to 200 meters in deep offshore areas. This coverage was developed to compliment other regional spatial data utilized by ocean planners in addressing management issues. It is intended only to provide general information on regional scale ocean depth and bottom morphology. There is a known gap in the Georgia coastal area, just north of Florida. A note concerning data scale: Scale is an important factor in data usage. Certain scale datasets are not suitable for some project, analysis, or modelling purposes. Please be sure you are using the best available data. 1:24000 scale datasets are recommended for projects that are at the county level. 1:24000 data should NOT be used for high accuracy base mapping such as property parcel boundaries. 1:100000 scale datasets are recommended for projects that are at the multi-county or regional level. 1:250000 scale datasets are recommended for projects that are at the regional or state level or larger. Vector datasets with no defined scale or accuracy should be considered suspect. Make sure you are familiar with your data before using it for projects or analyses. Every effort has been made to supply the user with data documentation. For additional information, see the References section and the Data Source Contact section of this documentation. For more information regarding scale and accuracy, see our web pages at: http://www.geoplan.ufl.edu/education.html
FGDL QUALITY ASSURANCE STATUS:
-Reprojected data to FGDL Albers HPGN (See "Map Projection Parameters" below) -Extent set to the State of Florida -DESCRIPT item was added based on DATASET -Upcased all character records
DATA LINEAGE SUMMARY:
In 2002, the GeoPlan Center downloaded this data in shapefile format from the Ocean Planning and Governance Geographic Information System (Ocean GIS) website: http://www.csc.noaa.gov/opis/html/data.htm. When received, the data was in the following projection: Geographic, Datum: NAD83, Spheroid: GRS1980, Units: Decimal degrees. The data was clipped to the State of Florida and lowercase characters within the attribute table were upcased.
MAP PROJECTION PARAMETERS:
Projection ALBERS Units METERS Datum HPGN Spheroid GRS1980 1st standard parallel 24 0 0.000 2nd standard parallel 31 30 0.000 Central meridian -84 0 0.000 Latitude of projection's origin 24 0 0.000 False easting (meters) 400000.00000 False northing (meters) 0.00000
DATA SOURCES CONTACT(S):
Name: NOAA Coastal Services Center
Abbr.name: NOAA
Address: 2234 South Hobson Ave.
Charelston, South Carolina,29405
Phone: (843) 740-1210
Fax: (843) 740-1224
Email: clearinghouse@csc.noaa.gov
FGDL CONTACT:
Name: Florida Geographic Data Library
Abbr. Name: FGDL
Address: Florida Geographic Data Library
431 Architecture
PO Box 115706
Gainesville, FL 32611-5706
Web site: http://www.fgdl.org
Contact FGDL:
Technical Support: http://www.fgdl.org/fgdlfeed.html
FGDL Frequently Asked Questions: http://www.fgdl.org/fgdlfaq.html
FGDL Mailing Lists: http://www.fgdl.org/fgdl-l.html
For FGDL Software: http://www.fgdl.org/software.html