Metadata for Benthic Habitats of the Florida Keys CD-ROM Includes metadata for all geographies. THE DATA PROVIDED ON THIS CD-ROM ARE NOT TO USED FOR NAVIGATION. last updated August 1998 Digital geographies are in geographic coordinates, decimal degrees, datum = NAD83, spheroid = GRS1980. When downloading the digital geographies, be sure to set the data transfer protocol to binary (bin). Data are available in Arc/Info interchange (e00) format. To download the text files, set the data transfer protocol to ASCII (asc). GENERAL INFORMATION - Benthic Habitats digital geography Name: BENTHIC_G Title: FLORIDA KEYS AND BISCAYNE BAY BENTHIC HABITATS Feature Type: POLYGON Geographic Extent: THE FURTHERMOST WESTERN BOUNDARY OF THE FLORIDA KEYS NATIONAL MARINE SANCTUARY (DRY TORTUGAS) NORTH TO WHERE 215TH STREET NORTHEAST IN DADE COUNTY INTERSECTS BISCAYNE BAY Creation Date: UNKNOWN Projection: GEOGRAPHIC COORDINATES, DECIMAL DEGREES Precision: SINGLE Datum: NORTH AMERICAN DATUM OF 1983 Accuracy: ACCURACY OF DISCRETE POINTS IS WITHIN TWO METERS. SHORELINE AND REEF HABITATS HAVE AN ACCURACY OF FIVER METERS. SEAGRASSES AND OTHER LESS RESISTANT HABITATS HAVE AN ACCURACY OF 10 METERS. Abstract: POLYGON GEOGRAPHY TO VISUALLY REPRESENT THE BENTHIC HABITATS GEOSPATIAL DATA OF SOUTH FLORIDA. Report last modified: 19980806 DATA SOURCE INFORMATION Organization: NOAA Contact: STEVE ROHMANN Address: 1305 East West Highway, Silver Spring, MD 20910 Phone Number: 301/713-3000x137 Electronic mail: steve.rohmann@noaa.gov Scale: UNKNOWN Projection: GEOGRAPHIC COORDINATES, DECIMAL DEGREES Precision: SINGLE Datum: NORTH AMERICAN DATUM OF 1983 Format: ARC/INFO e00 and ArcView shapefile DISTRIBUTION INFORMATION QA/QC Status: COMPLETE Distribution Status: AVAILABLE Data Format: ARC/INFO e00 and ArcView shapefile Contact: Steve Rohmann Address: 1305 East West Highway, Silver Spring, MD 20910 Phone Number: 301/713-3000x137 Electronic mail: steve.rohmann@noaa.gov Minimum mapping unit = 0.4 hectare (1 acre) for all habitat. Patch reefs may be <0.5 ha. DATA DICTIONARY Polygon attributes used in Benthic Habitat geography 01. Item: A_CODE ALPHA CODE FOR THE BENTHIC HABITATS Type: Character Length: 5 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: BM CARBONATE MUD BMd CARBONATE MUD; DREDGED/EXCAVATED BO ORGANIC MUD BS CARBONATE SAND BSb CARBONATE SAND; BANKS BSd CARBONATE SAND; DREDGE/EXCAVATED BUd BOTTOM UNKNOWN; DREDGED/EXCAVATED CB BACK REEF CPA AGGREGATED PATCH REEFS CPB CORAL PATCHES IN BARE SAND CPH HALO CPI INDIVIDUAL PATCH REEF CPIH INDIVIDUAL PATCH REEF AND HALO CPR REMNANT REEF CPSD REEF CONTAINING DROWNED SPUR AND GROOVE CPSS REEF CONTAINING SHALLOW SPUR AND GROOVE CR REEF RUBBLE h2o UNCLASSIFIED OCEANIC WATER HC SOFT CORAL,SPONGES,ALGAE HCb SOFT CORAL,SPONGES,ALGAE; BANKS HS HARDBOTTOM WITH PERCEPTIBLE SEAGRASS HSb HARDBOTTOM WITH PERCEPTIBLE SEAGRASS; BANKS HSd HARDBOTTOM WITH PERCEPTIBLE SEAGRASS; DREDGRED/EXCAVATED InW UNCLASSIFIED INLAND WATER LAND LAND SD MODERATE TO DENSE, CONTINUOUS BEDS SDb MODERATE TO DENSE, CONTINUOUS BEDS; BANKS SDd MODERATE TO DENSE, CONTIUOUS BEDS; DREDGED/EXCAVATED SDdr MODERATE TO DENSE, CONTIUOUS BEDS; DREDGED/EXCAVATED; RESTORATION SDr MODERATE TO DENSE, CONTIUOUS BEDS; RESTORATION SDB MODERATE TO DENSE, CONTIUOUS BEDS WITH BLOWOUTS SDBb MODERATE TO DENSE, CONTINUOUS BEDS WITH BLOWOUTS; BANKS SDBd MODERATE TO DENSE, CONTIUOUS BEDS WITH BLOWOUTS; DREDGED/EXCAVATED/RESTORATION SDBdr MODERATE TO DENSE, CONTIUOUS BEDS; DREDGED/EXCAVATED; RESTORATION SDBr MODERATE TO DENSE, CONTIUOUS BEDS WITH BLOWOUTS; RESTORATION SPA LARGELY MACROALGAL COVER WITH SCATTERED SEAGRASS PATCHES SPAb LARGELY MACROALGAL COVER WITH SCATTERED SEAGRASS PATCHES; BANKS SPH DENSE PATCHES OF SEAGRASS (>50%) IN A MATRIX OF HARDBOTTOM SPHb DENSE PATCHES OF SEAGRASS (>50%) IN A MATRIX OF HARDBOTTOM; BANKS SPHd DENSE PATCHES OF SEAGRASS (>50%) IN A MATRIX OF HARDBOTTOM; DREDGED/EXCAVATED SPP DOMINANTLY SAND OR MUD WITH SMALL SCATTERED SEAGRASS PATCHES (<50%) SPPb DOMINANTLY SAND OR MUD WITH SMALL SCATTERED SEAGRASS PATCHES (<50%); BANKS SPPd DOMINANTLY SAND OR MUD WITH SMALL SCATTERED SEAGRASS PATCHES (<50%); DREDGED/EXCAVATED SPS DENSE PATCHES OF SEAGRASS IN A MATRIX OF SPARSE SEAGRASS SPSb DENSE PATCHES OF SEAGRASS IN A MATRIX OF SPARSE SEAGRASS; BANKS SS SPARSE, CONTINUOUS BEDS SSb SPARSE, CONTINUOUS BEDS; BANKS U UNMAPPABLE/UNKNOWN BOTTOM 02. Item: AREA_METER AREA OF BENTHIC HABITAT IN SQUARE METERS Type: Integer Length: 16 Decimals: 0 Format: N/A Mandatory: N Default Values: 0 Item Values: N/A 03. Item: HAB_GROUP A Superclass aggregation of individual benthic habitats types Type: Character Length: 50 Decimals: 0 Format: N/A Mandatory: N Default Values: 0 Item Values: varies 04. Item: HAB_DESC A simplified text description of each benthic habitat type Type: Character Length: 70 Decimals: 0 Format: N/A Mandatory: N Default Values: 0 Item Values: see Additional Metadata - 1 05. Item: MODIFIER A text field containing the applicable special modifier for the benthic habitat polygon Type: Character Length: 50 Decimals: 0 Format: N/A Mandatory: N Default Values: 0 Item Values: see Additional Metadata - 2 for a detailed description of habitat modifiers. ADDITIONAL METADATA - 1 Benthic Habitats of the Florida Keys Classification System (Data Dictionary) Cross Reference Table of ARCINFO benthic_g geography and the ArcView Project files. The benthic habitat types found in the ArcView project files are provided below. Listed in parentheses with each benthic habitat type is the equivalent a_code(s) found in the ARCINFO benthic habitat geography. Within the ArcView project, benthic habitat modifiers (b - banks; d - dredged/excavated; r - restoration) are provided as a separate thematic layer. As a result, they are not included in this list. Also within the ArcView project, land (LAND) is provided as a separate thematic layer. As a result, it is not included in this list. A_CODE in the ArcView Shapefile Polygon Type BENTHIC_G ARCINFO geography ------------------------------------------------------------- Bare Substrate - Carbonate Mud BM Bare Substrate - Carbonate Sand BS Bare Substrate - Organic Mud BO Continuous Seagrass - Dense Patches in a Matrix of Sparse Seagrass (<50%) SPS Continuous Seagrass - Moderate to Dense SD Continuous Seagrass - Sparse SS Hardbottom - Perceptible Seagrass (<50%) HS Hardbottom - Soft Corals, Sponges, Algae HC Inland Water InW Patch Reefs - Aggregated CPA Patch Reefs - Aggregated with Halo CPIH Patch Reefs - Coral or Rock Patches with Bare Sand CPB Patch Reefs - Halo CPH Patch Reefs - Individual CPI Patchy Seagrass - Dense Patches in a Matrix of Hardbottom SPH Patchy Seagrass - Moderate to Dense with Blowouts SDB Patchy Seagrass - Predominantly Microalgae Cover with Scattered Seagrass Patches SPA Patchy Seagrass - Predominantly Sand and-or Mud with Small, Scattered Seagrass Patches (<50%) SPP Platform Margin Reefs - Back Reef CB Platform Margin Reefs - Drowned Spur and Groove CPSD Platform Margin Reefs - Reef Rubble CR Platform Margin Reefs - Remnant - Low Profile CPR Platform Margin Reefs - Shallow Spur and Groove CPSS Unknown Bottom BU; U More Metadata - 2 Descriptions of Benthic Habitats found in both the benthic_g ARCINFO geography and the ArcView project files. I. Coral Reefs A. Patch Reefs Discrete coral communities, typically dome-shaped, usually outside of Hawk Channel, with a few inshore. Can be linear features where several or a series occurs. Mostly off Key Largo and Elliot Key (5,000) with a few off Big Pine, near Key West, and at the Dry Tortugas. Usually composed of hard corals Montastraea sp., Siderastrea sp., Diploria sp., and Colpophyllia sp.. Often surrounded by a whitish appearing halo. 1. Individual Patch (CPI) Isolated, barely visible on aerial photography, with or without a halo. 2. Aggregated patch reefs (CPA) More than one, usually too close together to map individually or where halos coalesce. 3. Halo (CPH) Barren, essentially unvegetated, variable, whitish zone around patch reef resulting from grazing activity of urchins and fishes. Rubble from weathering of patch reef may allow attachment sites for corals to expand the colony. Not always present or large enough to be mapped. 4. Individual Patch Reef and Halo (CPIH) Patch reef and halo combination too small to delineate directly on aerial photography. Delineations of reef and halo performed during compilation. B. Platform Margin Reef Generally, the "reef tract" or "barrier reef." Extends from northern boundary of the Florida Keys National Marine Sanctuary to west of the Marquesas Keys and also found at the Dry Tortugas. Diverse communities variable in morphology and species composition. Both high and low relief. Includes all coral/hardbottom features distinguishable from "patch reefs." 1. Spur and Groove a. Shallow (e.g., Looe Key) (CPSS) Well developed systems on "fore-reef" at major bank reefs on reef tract, with vertical relief to about 4m. Actively growing upward and outward. Distinctive signature on aerial photography due to shallow water (0 - 10m) and high vertical relief. Linear length to approximately 1000m or more. b. Drowned (Transitional = older, drowned) (CPSD) Older, not actively growing (probably eroding) features often being buried by sand migration from shallower zone of reef tract. Nearly typical spur and groove signature in aerial photographs, but sometimes with less resolution or definition. Usually low profile, about 0.5 - 1.5m. Visible to interpretable depth of photography (10m). Often greater linear length than shallow spur and groove. 2. Remnant - Low profile (CPR) Coral/hardbottom features not exhibiting distinctive signature of spur and groove reefs. Usually parallel to line of reef tract, but may form transverse features perpendicular to the reef tract. Relief from less than 0.5m - 1 or 2m. C. Coral Patches in Bare Sand (CPB) Very sparse features that are similar in nature to patch reefs, but are on the outer reef tract. These areas are dominantly sand or a veneer of sand over low relief rock. Scattered throughout are small patches ranging from a single gorgonian, sponge, or small coral head up to a low assemblage that may be a few meters to 10m across. These patches make up a low percentage of the total cover, yet are distinctive. This class is found mainly in the area from Big Pine Shoal to Sombrero Light, and may be associated with the lack of a developed forereef structure in this area. D. Back Reef (CB) Shallow (<2m) platform landward of spur and groove features on bank reefs, typically rubble zone colonized with numerous soft corals and pioneering staghorn, fire and other hard corals. Corals here are widely spaced individuals on a rubble platform. E. Reef Rubble (CR) Zone landward of bank reefs and other high energy reef tract areas where unstable rubble exists with little or no visible colonization. In relatively shallow water (1 - 6m) often in association with Thallassia or Syringodium. Signature on the aerial photographs is distinctive from other coral/hardbottom communities. May form transverse features perpendicular to line of reef tract. II. Hardbottom (Inshore only, stops at Hawk Channel for the Florida Keys National Marine Sanctuary) Solid, flat, low-relief substrate composed of Key Largo limestone (from west end of the Newfound Harbor Keys off Big Pine to the north edge of the Florida Keys National Marine Sanctuary) or Miami oolite (Big Pine Key and west). Depth ranges from intertidal to approximately 7m in deep tidal channels and the inside edge of Hawk Channel. May include a thin veneer of carbonate sand or mud, too thin and unstable to support seagrass. A. Soft Coral, Hard Coral, Sponge, Algae (HC) Benthic community (no perceptible seagrass) is variable and typically a function of sediment, water, depth, and exposure to wind and current. May also include solitary hard corals, Porites sp., Sideratrea sp., and Manicina sp.. Shallowest zones (<1m) may include only attached or drift algae; soft corals are usually more common in deeper zones. B. Hardbottom with perceptible seagrass (<50%) (HS) Usually in patches, seagrasses occur in depressions and basins where adequate sediment has accumulated, but constitute <50% bottom coverage. Hard bottom may include solitary hard corals and soft corals, but most often sponges and benthic algae (attached or in draft). III. Bare Substrate Open and essentially unvegetated, with no benthic community visible on photographs, due to unstable nature of substrate. Can be large seagrass blowouts or active erosional features. Largest areas are on reef tract, in the bottom of Hawk Channel and west of the Marquesas Keys. May have sparse, ephemeral benthic algae or diatom films that are not detectable on photography. Diatom films may develop in a few days. A. Carbonate Sand (usually exposed locations) (BS) Sand-size carbonate sediments, usually in areas exposed to current and wind energy that continually sort out and remove finer sediment fractions. B. Carbonate Mud (usually protected location) (BM) Fine carbonate sediments in deep water (Hawk Channel) or locations protected from wind and wave energy. More depositional than erosional. C. Organic Mud (BO) On windward shorelines where drift seagrass and algae builds up in intertidal and shallow water. Continual deposition and resuspension of organic matter limits development of benthic community on natural as well as disturbed shorelines. Especially common feature on windward shorelines of Big Pine, No Name, and Little Pine Keys. IV. Seagrass A. Moderate to Dense, continuous beds (SD) Solid, continuous Thalassia, Syringodium, and Halodule, individually or in mixed beds. Widespread in occurrence with range in depth from intertidal (bank) to approximately 10m. B. Moderate to Dense, nearly continuous beds (seagrass>50%), with blowouts and/or sand or mud patches. (SDB) Solid, continuous Thalassia or Syringodium, rarely Halodule, individually or in mixed beds. Widespread in occurrence with range in depth from intertidal (bank) to approximately 10m. Moderate to high energy regimes. Here, blowouts or patches are dispersed as holes in otherwise continuous seagrass beds. Usually found on reef tract and near entrances to tidal channels and passes. A common habitat in back country of middle keys with large water movements between the Gulf of Mexico and Atlantic Ocean. C. Sparse, continuous beds (SS) Areas where seagrasses occur in low density (<50 shoots/m sq.). Typically in shallow protected bays where physical conditions or substrate limits development. May be hard to distinguish signature on aerial photographs from barren bottom, requiring ground truthing. D. Patchy Typically the result of depressional basins or creek-like features in seabed that accumulate sediment or contain organic peat deposits from mangrove community occurring during lower sea level. This greater depth of sediment allows seagrass development in an area, or allows denser seagrasses compared to surrounding areas. Widespread feature in inshore areas throughout the Florida Keys National Marine Sanctuary and Biscayne Bay. 1. Dense patches of seagrass (>50%) in a matrix of Hardbottom. (SPH) One of the most common habitat types; patches occur in areas where a thin sediment layer over flat natural rock precludes development of seagrasses. Often numerous in number, highly visible on aerial photographs. 2. Dense patches of seagrass in a matrix of sparse seagrass. (SPS) Depressional features with deep sediment allow denser development of seagrasses than on surrounding bottoms where only a thin layer may be present. May be difficult to discern on aerial photographs from seagrass patches in hardbottom. May occur more in deeper water or protected bays. 3. Dominantly sand or mud with small scattered seagrass patches (<50%). (SPP) Large sand features with recognizable seagrass patches. Similar location to seagrass with blow-outs. Substrate may vary from sand to mud, and algae, either fixed or drift, may be a significant component. Offshore features tend to be more sandy, and inshore protected areas tend to be muddier in composition. 4. Largely MacroAlgal cover with scattered seagrass patches. (SPA) Scattered seagrass patches are a significant habitat component, but dominant is background of macroalgae. Algal cover is banks of Halimeda sp. or Pencillus sp. May be difficult to delineate on aerial photographs without ground truthing. V. Special Modifiers Special Modifiers are attached to a specific community type when applicable. Ex. SDb; BSDBr A. Banks (Xb) Intertidal seagrass and some hardbottom communities, even if only intertidal at spring low tides, often open water features or extending out from a shoreline. Distinctive signature on aerial photographs compared to surrounding bottom. Sometimes burned off patches are present on bank top. If these patches become large enough, they are mapped as separate bare areas. B. Dredged/Excavation (Xd) Those locations where dredging or excavation has occurred for channels, rock mines, or anchorages. C. Restoration (Xr) Site of fill placement or backfilling of dredged area to restore original elevations and intertidal or benthic community. Modifier applied to resulting benthic community. Local knowledge of restoration sites necessary. VI. Bottom Unknown, Unmappable, or Uninterpretable (BU; U) This refers to those areas that are beyond the depth threshold of the aerial photography (approximately 9m), and/or uninterpretable due to glare, or turbid waters. Most narrow or deep access channels such as Key West Harbor, Hawk Channel, or the deeper sides of the reef tract. **************************************** GENERAL INFORMATION - Bathymetric Contours Name: BATHY Originator: NOAA-National Ocean Service Publication_Date: 19980606 Title: Bathymetry contours Publication_Information: Publication_Place: Silver Spring, MD Publisher: NOAA-National Ocean Service Abstract: These Bathymetric Digital Elevation Models (DEM) were generated from original point soundings collected during hydrographic surveys conducted by the National Ocean Service and its predecessors. Mean High Water shoreline as defined by NOAA nautical charts was used as a constraining boundary and assigned its local elevation relative to the local datum (typically Mean Low Water). DEM grid values outside the shoreline (on land) were assigned null values (-32676). In the event of multiple surveys in a region, the most recent survey soundings were retained. Both 7.5 minute and 1 degree DEMs are available. 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 {0.01 meter]) per each profile. The last physical record of the DEM is an accuracy record (C-record). The 1 degree (60-minute) DEMs (3 arc second x 3 arc second dataspacing) is cast on the geographic coordinate system (no projection). It provides coverage in 1 degree square blocks. Each product contains over edge data. Coverage is available for the many estuaries of the conterminous United States, but is not complete. 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. Purpose: Bathymetric DEM's can be used as layers in geographic information systems for earth science analysis. DEM's can also serve as tools for volumetric analysis, for site location of structures, or for drainage basin delineation. The source soundings are collected by the National Ocean Survey. Supplemental_Information: The datum for these bathymetric DEMs (Mean Low Water) is not the same as that used by the US Geological survey (USGS) for land based DEMs (NAV29) which results in a discontinuity of about _ the tidal range. Moreover, the shoreline for the USGS DEMs is indeterminate and not the same as that used for the Bathymetric DEMs. Furthermore, the vertical resolution is smaller and accuracy of the Bathymetric DEMs is better than USGS DEMs. Because of these differences, extreme care should be used in merging NOAA and USGS DEM data. One Degree bathymetric DEMs have profiles (north-south lines) containing 1201 soundings. Missing values (over land as defined by the Mean High Water Line) are filled with null values represented by the value -32676. Profiles within the One degree square which contain only null values are omitted. 7.5-minute DEMs have rows and columns which vary in length and are staggered. The UTM bounding coordinates form a quadrilateral (no two sides are parallel to each other), rather than a rectangle. The user will need to pad out the uneven rows and columns with blanks or flagged data values, if a rectangle is required for the user's application. Some software vendors have incorporated this function into their software for input of standard formatted USGS DEMs. Access_Constraints: none Use_Constraints: Not to be used for Navigation. Acknowledgment of the National Oceanic and Atmospheric Administration, National Ocean Service would be appreciated in products derived from these data. The datum for these bathymetric DEMs (Mean Low Water) is not the same as that used by the US Geological survey (USGS) for land based DEMs (NAV29) which results in a discontinuity of about _ the tidal range. Moreover, the shoreline for the USGS DEMs is indeterminate and not the same as that used for the Bathymetric DEMs. Furthermore, the vertical resolution is smaller and accuracy of the Bathymetric DEMs is better than USGS DEMs. Because of these differences, extreme care should be used in merging NOAA and USGS DEM data. Attribute_Accuracy_Report: The accuracy of a DEM is dependent upon the level of detail of the source soundings and the grid spacing used to sample that source. The primary limiting factor for the level of detail of the source is the scale of the source survey, the technology used to collect soundings, and the resolution of the source soundings. Additional complications is describing accuracy are the ages of the surveys used to collect sounding in a given area. Care was used to use the most recent surveys covering a given area but in some instances adjacent surveys may be decades apart in age. In some regions, the only source data were at fathom (6 feet) resolution. In general, most source surveys were certified to one foot or better by the National Ocean Service. Logical_Consistency_Report: The fidelity of the relationships encoded in the data structure of the DEM are automatically verified using a NOAA-NOS software program upon completion of the data production cycle. The test verifies full compliance to the DEM specification. Completeness_Report: The DEM is visually inspected for completeness on a DEM view and edit system for the purpose of performing a final quality control and if necessary, edit of the DEM. The physical format of each digital elevation model is validated for content completeness and logical consistency during production quality control and prior to archiving in the National Geographic Data Center. Due to the variable orientation of the 7.5 minute quadrilateral in relation to the Universal Transverse Mercator (UTM) projection grid, profiles that pass within the bounds of the DEM quadrilateral may be void of elevation grid points and are not represented in the DEM. This condition occurs infrequently and is always the first or last profile of the dataset. DEM's may contain void areas caused by elevations being above Mean High Water or on non tidal land. Void area elevation grid posts are assigned the value of -32,767. In addition, suspect elevation areas may exist in the DEM but are not specifically identified. Horizontal_Positional_Accuracy_Report: The horizontal accuracy of the DEM is expressed as an estimated root mean square error (RMSE). The estimate of the RMSE is based upon horizontal accuracy tests of the source soundings used to generate the DEM. As a first approximation the locational accuracy of the source soundings are 0.0015 m at source smooth sheet scale (120 m @ 1:80,000 to 15 m @ 1:10,000) Horizontal_Positional_Accuracy_Explanation: Digital elevation models meet horizontal National Map Accuracy Standards (NMAS) accuracy requirements. Vertical_Positional_Accuracy_Report: The vertical RMSE statistic is used to describe the vertical accuracy of a DEM. It encompasses both random and systematic errors introduced during production of the data. The RMSE is encoded in element number 5 of record C of the DEM. This accuracy estimate includes components related to quantization of the source soundings (1.3 to 0.15 m), the systematic editing of the source data (1% or 0.10m), un-sampled bathymetric features (estimated at less than 5% of depth), time related changes (erosion, deposition, and seismic shifts), and dredging operations (cut and fill) It is estimated that the accuracy of the Bathymetric DEMs is 2% of depth or 1 meter for depths grater than 20 meters and 2 % of depth or 0.20 meters for depths shallower than 20 meters. These DEMs are NOT to be used for navigation. There are three types of DEM vertical errors: blunder, systematic, and random. These errors are reduced in magnitude by editing but cannot be completely eliminated. Blunders are errors of major proportions and are easily identified and removed during interactive editing. Systematic errors follow some fixed pattern and are introduced by data collection procedures and systems. Systematic error artifacts include vertical unsampled elevation shifts, relative spacing of the source soundings, misinterpretation of terrain surface caused by softness or poor reflectivity and by the resolution of the collected soundings (feet, feet & fractions, fathoms, fathoms & fractions, meters, tenths of meters etc.). Random errors result from unknown or accidental causes. The 1 degree (DSQ) DEMs are generated from 30 m grids on UTM projection. The rms difference between these surfaces is an estimate of the vertical accuracy of the DSQ DEMs. Originator: National Oceanic and Atmospheric Administration Publication_Date: 19970000 Title: National Ocean Service- Hydrographic Survey Data Publication_Place: Boulder CO Publisher: National Geophysical Data Center Type_of_Source_Media: CD-ROM Range_of_Date/Time: the date of Hydrographic Survey Begining_Date: "Unknown" Ending_Date: "Unknown" Source_Currentness_Reference: date of surveys Source_Citation_Abbreviation: GEODAS vol 2 ver 3.3 Source_Contribution: Hydrographic Soundings Source_Citation: Originator: U.S. Geological Survey or National Geodetic Survey (NGS) Publication_Date: 19920503 Title: project control Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Type_of_Source_Media: magnetic tape Source_Time_Period_of_Content: Single_Date/Time: Unknown Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: CONTROL1 Source_Contribution: ground control points Process_Description: The production procedures, instrumentation, hardware, and software used in the collection of standard National Oceanic and Atmospheric Administration (NOAA) Bathymetric Digital Elevation Models (DEM's) vary depending on systems used at the time of the survey. Documentation Logsheets were kept at all stages of processing to track file names, dates, hydrographic survey coverage, and soundings or hydrographic surveys that were deleted as part of the quality control process. A short summary of the processing steps for each estuary is available on the individual data pages. In addition, a list of each of the surveys which were included is accessible through the individual data pages. Overview Original hydrographic data from the National Ocean Service and it predecessors was used exclusively as source data. Processing was performed on desktop computers using a variety of commercial and custom software systems. The two main software systems used were Digital Optimization of Grid Systems (DOGS) version 1.5x software developed by NOAA and MapInfo Professional version 4.5 published by MapInfo augmented by a MapInfo add-on named Vertical Mapper published by Northwood Geosciences. The processing sequence for each estuary started with the generation of a comprehensive source data set from the NOS archives, These source sounding were quality controlled to eliminate outliers and superseded surveys, optimized to reduce the number of data values, augmented with points representing the Mean High Water shoreline, and then gridded. The gridded data sets were converted from the internal proprietary grid format to Digital Elevation Model (DEM) format for public distribution. Creating Point Sets of Hydrographic Survey Data Sounding data obtained from Hydrographic Surveys were extracted using DOGS from the GEODAS CD distributed by the National Geophysical Data Center using each estuary's shoreline as a clipping boundary. Large estuaries were broken into several overlapping regions and subsets of points were extracted and processed. Most historic hydrographic surveys are included on the GEODAS CD. For those regions which were missing data (parts of southern Florida & Chesapeake Bays only), soundings were digitized from a hard copy Smooth sheets generated by the Hydrographic surveys. Editing and Quality Control of Bathymetry Point Data The first step of the quality control was to review the data using the DOGS software. The data were first examined for surveys or parts of surveys that are redundant. For many areas there are more surveys than are actually useful. Entire surveys or large portions of surveys were deleted for the following reasons. Another more recent survey fully covers the same area. The survey has questionable values which can not be fixed by way of figuring out a mathematical update value for the entire survey, and there are too many bad points to pick out probable 'good' values. Sections of surveys were omitted if they were overlapped by more accurate surveys or by similar yet denser coverage. The second step was to display the data by depth values and to remove stray points that were obvious outliers from the surrounding data values. Optimizing the Bathymetry Point Data using DOGS The data was first triangulated in DOGS in order to optimize the set of points. The computer program DOGS can analyze a large set of bathymetric data and create from it a smaller set of optimized points which describes the bathymetry of a geographic region to within a user defined error. This smaller data set then can be used on its own as a representation of the area's bathymetry, or as input into other computer programs or Geographical Information Systems. There are two calculation options for triangulation in DOGS: relative and absolute. Bathymetry point files were cut into sections for separate processing based on mean depth of 10 meters. A relative height error criteria of 0.01 was used for the triangulation of regions whose depths averaged above 10 meters. An absolute height error criteria of 0.1 meters was used for areas with average depths less than 10 meters. The two resultant files were saved as text files. After combining these files, the vertical error associated with the optimized data set was 1% of depth or 0.1 meters, whichever was greater. The optimized DOG file was imported into MapInfo's MapInfo Professional desktop mapping software. Augmenting the data set with Shoreline Points The final bathymetry was clipped to NOAA's 1:250,000 or 1:80,000 Coastal Assessment Framework (CAF) shoreline, depending on which was available at the time of processing (Only a few of the estuaries have 1:80K shoreline data). A copy of the shoreline file was edited to create a point file from the vector vertices and optimized using DOGS to produce a more workable, smaller file, with little compromise to the shape of the shoreline. Mean High Water tide level was assigned to the shoreline points to give them a height. These Shoreline data points were added to the set of bathymetry points before doing the final triangulation in MapInfo. Generation of a Gridded Bathymetry Dataset Linear triangulation of the combined point files were done in MapInfo using the Vertical Mapper 2.0 partner product software. The resultant TIN file was then used to create a continuous grid file with 30 meter resolution on a UTM projection using a NAD27 horizontal datum. A second grid was created from the first by aggregating the 30 meter grid values to 90 meter resolution and performing a rectangular interpolation to a geographic 3 arc second resolution grid. Both grids were cut to the estuary boundary shoreline. 7.5 minute and 1 degree sections were then created from these grids. The 7.5 minute grids have 30 meter resolution in a UTM projection using the NAD27 datum. The 1 degree grids have a 3 arc second resolution in a geographic projection (Latitude/Longitude) using the NAD27 datum. In their native form, both of these grids are in proprietary formats. Creating Polygon Contour Intervals (available for Florida Bay only) 12 separate 1 degree sections (3 arc second) were contoured using Vertical Mapper's contouring tools within MapInfo. The contours are created from the GRD files created by processes described in the preceding paragraph. Each grid was contoured individually, and contour intervals were input by the technician. Each of the 1 degree polygon contour sections was exported from MapInfo's MIF format to ArcView's SHP format. The 12 SHP files were then imported into ArcView 3.0 and like depths joined with the Śmerge features' tool after straight-line heads-up editing was performed to close gaps or eliminate overlaps as necessary, thus creating a single continuous data file. Creating DEM files The MapInfo grid files were converted to a public domain USGS format DEM files using the NOAA DEM maker software. The formats available for downloading are 30 meter & 3 arc second DEMs in USGS DEM format. DEM's are viewed on interactive editing systems to identify and correct blunder and systematic errors. DEM's are verified for physical format and logical consistency. Direct_Spatial_Reference_Method: raster Raster_Object_Information: Raster_Object_Type: grid cell Row_Count: 1201 Column_Count: up to 1201 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude resolution: 0.000833333 Longitude resolution: 0.000833333 Geographic_Coordinate_Units: Decimal degrees Geodetic_Model: Horizontal_Datum_Name: North American Datum 1983 Ellipsoid_Name: GRS80 Altitude_Datum_Name: Mean Low Water Datum Altitude_Resolution: 1 Altitude_Distance_Units: meters Altitude_Encoding_Method: explicit elevation coordinate included with horizontal coordinates Entity_and_Attribute_Overview: The digital elevation model is composed of a elevation value linked to a grid cell location representing a gridded form of a bathymetric map overlay. Each grid cell entity contains a 6-character integer value between -32,767 and 32,768. The grid is generated from profiles of data each containing header information (profile identifier, starting point, relative datum for profile values (deepest value within the DEM), number of values, etc) followed by profile values relative to the relative datum for the profile. All non-null values in the profile are positive. DATA DICTIONARY .PAT FILE 01. Item: MIN_DEPTH Description: Minimum depth in meters associated with bathymetric contour Type: Integer Length: 4 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: varies 02. Item: MAX_DEPTH Description: Maximum depth in meters associated with bathymetric contour Type: Integer Length: 1 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: varies 03. Item: DEPTHRANGE Description: Range of depths in meters characterized by the bathymetric contour Type: Character Length: 12 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: varies 04. Item: DEPTH_ZONE Description: Aggregated range of depths in meters characterized by the bathymetric contour. This attribute used for legend display. Type: Character Length: 12 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: varies 05. Item: RANGEORDER Description: A code used to control bathymetric contour display order and for legend display. Type: Character Length: 2 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: varies 06. Item: ZONE_ORDER Description: A code used to control bathymetric contour display order and for legend display. Type: Character Length: 1 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: varies **************************************** GENERAL INFORMATION - Aids to Navigation Name: ATONS Title: U. S. COAST GUARD AIDS TO NAVIGATION (ATONS) Feature Type: POINT Geographic Extent: STATEWIDE Creation Date: UNKNOWN Projection: GEOGRAPHIC COORDINATES Units: DECIMAL DEGREES Spheroid: GRS1980 Precision: SINGLE Datum: NAD83 Accuracy: UNKNOWN Purpose: TO VISUALLY REPRESENT GEOSPATIAL DATA Description-Abstract: THE TERM "AIDS TO NAVIGATION" REFERS TO A DEVICE OUTSIDE OF A VESSEL USED TO ASSIST MARINERS IN DETERMINING THEIR POSITION OR SAFE COURSE, OR TO WARN THEM OF OBSTRUCTIONS. AIDS TO NAVIGATION INCLUDE LIGHTHOUSES, LIGHTS, BOUYS, SOUND SIGNALS, LANDMARKS, RACONS, RADIO BEACONS, LORAN, AND OMAGA. THESE INCLUDE AIDS WHICH ARE INSTALLED AND MAINTAINED BY THE COAST GUARD AS WELL AS PRIVATELY INSTALLED AND MAINTAINED AIDS (PERMIT REQUIRED). THIS DOES NOT INCLUDE UNOFFICIAL AIDS (ILLEGAL) SUCH AS STAKES, PVC PIPES, AND SUCH PLACED WITHOUT PERMISSION. THIS DATA SET IS NOT CERTIFIED FOR NAVIGATION AND IS NOT INTENDED TO BE USED FOR NAVIGATION PURPOSES. EACH USCG DISTRICT HEADQUARTERS IS RESPONSIBLE FOR UPDATING THEIR DATABASE ON AN "AS NEEDED" BASIS. WHEN EXISTING AIDS ARE DESTROYED OR RELOCATED AND NEW AIDS ARE INSTALLED THE DATABASE IS UPDATED. EACH AID IS ASSIGNED AN OFFICIAL "LIGHT LISTING NUMBER." THE LIGHT LIST IS A DOCUMENT LISTING THE CURRENT STATUS OF ATONS AND IT IS PUBLISHED AND DISTRIBUTED ON A REGULAR BASIS. INTERIM CHANGES TO THE LIGHT LIST ARE PUBLISHED IN LOCAL NOTICES TO MARINERS WHICH ARE THE OFFICIAL MEANS WHICH NAVIGATORS ARE SUPPOSED TO KEEP THEIR CHARTS CURRENT. IN ADDITION, THE USCG BROADCASTS NOTICES TO MARINERS ON THE MARINE BAND RADIO AS SOON AS CHANGES OF THE STATUS OF INDIVIDUAL AIDS ARE REPORTED. THE LIGHT LIST NUMBER AND LOCAL NOTICE TO MARINERS ARE SUGGESTED WAYS TO KEEP THE DATABASE CURRENT ON A REGULAR OR EVEN "REAL TIME" BASIS. HOWEVER, ANNUAL (OR MORE FREQUENT) UPDATES OF THE ENTIRE DATASET COULD BE OBTAINED FROM EACH USCG DISTRICT HEADQUARTERS. POSITIONAL ACCURACY: THE LOCATIONS OF THESE AIDS ARE DETERMINED BY VARIOUS MEANS INCLUDING USCG MAINTENANCE CREWS, INSTATLLATION CONTRACTORS, USCG AUXILIARY CREWS, AND PERMIT APPLICATIONS. ALTHOUGH THE USCG CONDUCTS ROUTINE CHECKS ON POSITIONS, THE COORDINATES IN THIS DATASET MIGHT NOT REPRESENT THE EXACT LOCATION OF INDIVIDUAL AIDS. BOUYS ARE ATTACHED TO THE SEA FLOOR WITH LONG CHAINS AND WILL NOT HAVE CONSISTENT POSITIONS. BE WARNED THAT TYPOGRAPHICAL ERRORS DO EXISTS IN THIS DATASET. Report last modified: 19970630 DATA SOURCE INFORMATION Organization: AIDS TO NAVIGATION AND WATERWAYS MANAGEMENT BRANCH Contact: COMMANDER (OAN) Address: SEVENTH COAST GUARD DISTRICT 909 SE FIRST AVENUE MIAMI, FLORIDA 33131-3050 Phone Number: (305) 536-5621 OR FAX (305) 530-7655 Scale: UNKNOWN Projection: UNKNOWN Precision: UNKNOWN Datum: UNKNOWN Accuracy: UNKNOWN Source Format: COAST AND GEODETIC SURVEY. THE COORDIINATES OF THE ATONS WERE USED WITH THE ARC/INFO 'GENERATE' COMMAND TO CREATE THE COVERAGE. *NOTE: DATA FOR THE EIGHTH DISTRICT (PANHANDLE) WAS OBTAINED FROM THE EIGTH DISTRICT, MOBILE, ALABAMA. DISTRIBUTION INFORMATION QA/QC Status: INCOMPLETE Distribution Status: CONDITIONALLY AVAILABLE Data Format: ARC/INFO EXPORT FILE (.e00), ARC/VIEW SHAPEFILE FWRI Contact: Kathleen O'Keife FWRI Address: FLORIDA FISH AND WILDLIFE CONSERVATION COMMISSION FISH AND WILDLIFE RESEARCH INSTITUTE 100 8TH AVENUE S.E. ST. PETERSBURG, FL 33701-5095 FWRI Phone: 727/896-8626 DATA DICTIONARY .PAT 01. Item: LINK Description: USED TO CREATE COVERAGE, USELESS Type: B Length: 4 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: UNIQUE 02. Item: UNIQUE_ID Description: UNIQUE NUMBER FOR EACH ATON ASSIGNED AFTER DATA WERE RECEIVED FROM THE USCG. THE USCG LIGHT LIST NUMBER CAN NOT BE USED TO PERMANENTLY IDENTIFY ATONS BECAUSE THESE NUMBERS ARE REASSIGNED EVERY SIX TO TWELVE MONTHS. Type: N Length: 5 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: UNIQUE 03. Item: DATA_DATE Description: DATE THE DATA WAS RECEIVED FROM THE USCG OR UPDATED THROUGH USE OF LOCAL NOTICE TO MARINERS, NOAA NAUTICAL CHARTS, OR FIELD MEASUREMENTS. Type: DATE Length: 8 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: VARIES 04. Item: CLASS Description: INDICATES FEDERAL OR PRIVATE ATON Type: C Length: 7 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: "FEDERAL", "PRIVATE", OR BLANK 05. Item: AID_NAME Description: BRIEF DESCRIPTION OR NAME ASSIGNED BY THE USCG Type: C Length: 35 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: VARIES 06. Item: AID_TYPE Description: CODE IDENTIFYING THE TYPE OF AID. EACH TYPE OF AID HAS A SPECIFIC FUNCTION FOR NAVIGATION AND IS USUALLY READILY IDENTIFIABLE IN THE FIELD BY ITS UNIQUE PHYSICAL CHARACTERISTICS. Type: C Length: 8 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: DBN - DAYBEACON: A LARGE WOODEN POLE WITH EITHER A RED TRIANGULAR OR A GREEN SQUARE PLACARD ON TOP. INFORMATINAL DAYBEACONS WILL HAVE A WHITE SQUARE PLACARD. THESE ARE THE MOST COMMON AIDS AND ARE INTENDED PRIMARILY FOR USE DURING DAYLIGHT HOURS, HENCE THE NAME. LT - LIGHT: A DAYBEACON WITH A FLASHING LIGHT FOR USE DURING PERIODS OF DARKNESS. LH - LIGHTHOUSE: VERY TALL, LARGE, SOLID STRUCTURE WITH A VERY INTENSE LIGHT. IN THE KEYS REEF SYSTEM THESE ARE THE IRON FRAME TOWERS. B - BUOY WB - WHISTLE BUOY BB - BELL BUOY LB - Lighted Buoy LGB - Lighted Gong Buoy LWB - Lighted Whistle Buoy LBB - LIGHTED BELL BUOY RFL - RANGE LIGHT FORWARD RRL - RANGE LIGHT REAR RBN - RADIO BEACON ANTENNA ODAS - OCEAN DATA ACQUISTION SYSTEM. NOAA'S AUTOMATED DATA COLLECTION BUOYS. PLATFORM - PLATFORM TWR - N/A 07. Item: AID_LABEL Description: ANY IDENTIFICATION MARKS DISPLAYED ON THE ACTUAL AID. MOST OFTEN THIS IS A NUMBER BUT PORT ENTRANCE BOUYS WILL HAVE THE PORT INITIALS PAINTED ON THE BOUY AND SOME BOUYS WHICH MARK HAZARDOUS WRECKS WILL BE IDENTIFIED WITH "WR". Type: C Length: 12 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: VARIES 08. Item: ODD_EVEN Description: IN MOST CASES AIDS MARKING A NARROW CHANNEL WILL BE LOCATED AS GATED PAIRS WITH AIDS ON ONE SIDE OF THE CHANNEL BEING ASSIGNED AN ODD NUMBER AND AIDS ON THE OTHER SIDE BEING ASSIGNED AN EVEN NUMBER. "E" FOR EVEN, "O" FOR ODD. IF THE AID HAS NO NUMBER THEN THIS FIELD IS BLANK. WHEN AIDS ALONG A NARROW CHANNEL ARE DISPLAYED ON A SMALL SCALE MAP, THE MAP CAN BE CLUTTERED WITH AID SYMBOLS. THIS ODD/EVEN DESIGNATION ALLOWS FOR ONLY AIDS ON ONE SIDE OF A CHANNEL TO BE DISPLAYED THEREBY ELIMINATING CLUTTER. Type: C Length: 1 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: O = ODD E = EVEN 09. Item: DECI_LAT Description: LATITUDE IN DECIMAL DEGREES (NAD 83) Type: N Length: 10 Decimals: 7 Format: N/A Mandatory: N Default Values: N/A Item Values: VARIES 10. Item: DECI_LON Description: LONGITUDE IN DECIMAL DEGREES (NAD 83) Type: N Length: 11 Decimals: 7 Format: N/A Mandatory: N Default Values: N/A Item Values: VARIES 11. Item: COMMENTS Description: SPECIFIC COMMENTS, WARNINGS, OR INSTRUCTIONS REGARDING THE STATUS OR USE OF THE ATON. "TEMPORARY" IS A COMMON VALUE WHICH INDICATES THAT, AT THE TIME OF DATA RELEASE, THE AID AT THIS LOCATION WAS A TEMPORARY AID REPLACING A DESTROYED AID. THIS ALERTS THE DATABASE ADMINISTRATOR OF THE NEED TO OBTAIN NEW DATA ABOUT THE AID IN THE FUTURE. Type: C Length: 40 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: VARIES 12. Item: SYMBOL Description: VALUES PLACED IN THIS FIELD DESIGNATE WHAT SYMBOL BEST REPRRESENTS THE AID FOR CARTOGRAPHIC PURPOSES. Type: C Length: 2 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: RANGE 1 TO 26 13. Item: DISTRICT Description: INDICATES THE COAST GUARD DISTRICT IN WHICH THE ATON IS LOCATED Type: C Length: 12 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: "SEVENTH" OR "EIGHTH" 14. Item: METHOD Description: METHOD OF IDNTIFYING ATON LOCATION Type: C Length: 2 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: BG = BEST GUESS (POSITION APPROXIMATE) CG = REPORTED BY USCG DG = FIELD MEASUREMENT BY DIFFERENTIAL GPS WG = WILD GUESS (POSITION QUESTIONABLE) YE = PLOTTED FROM NAUTICAL CHART 15. Item: SYM Description: A CATEGORY ITEM USED WHEN ADDING LEGEND FEATURES TO ATONS WITHIN ARCVIEW Type: C Length: 2 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A ************************************ GENERAL INFORMATION - Roads Name: ROADS Title: CENSUS 1:100000 ROADS IN FLORIDA Feature Type: ARC Geographic Extent: STATEWIDE Creation Date: 1990 Projection: GEOGRAPHIC COORDINATES Units: DECIMAL DEGREES Spheroid: GRS1980 Precision: SINGLE Datum: NAD83 Accuracy: UNKNOWN Description-Abstract: THIS IS A LINE COVERAGE OF ROADS FROM 1990 TIGER DATA. DATA SOURCE INFORMATION Organization: FLORIDA SENATE REAPPORTIONMENT COMMITTEE Contact: LINK CLAY Address: UNKNOWN Phone Number: (904) 487-0400 Scale: 1:100000 Projection: UNKNOWN Precision: UNKNOWN Datum: UNKNOWN Accuracy: UNKNOWN Source Format: UNKNOWN DISTRIBUTION INFORMATION QA/QC Status: INCOMPLETE Distribution Status: AVAILABLE WITH PERMISSION Data Format: ArcView shapefile FWRI Contact: KATHLEEN O'KEIFE FWRI Address: FLORIDA FISH AND WILDLIFE CONSERVATION COMMISSION FISH AND WILFLIFE RESEARCH INSTITUTE 100 8TH AVE S.E. ST. PETERSBURG, FL 33701-5095 FWRI Phone: (727) 896-8626 DATA DICTIONARY .AAT FILE 01. Item: RECNUM Description: UNIQUE NUMBER FOR EACH ARC Type: F Length: 8 Decimals: 0 Format: N/A Mandatory: Y Default Values: N/A Item Values: UNIQUE FOR EACH ARC 02. Item: CFCC Description: CENSUS FEATURE CLASS CODE. A CFCC IS USED TO IDENTIFY THE MOST NOTICABLE CHARACTERISTIC OF A FEATURE. FOR THIS COVERAGE, ALL FEATURES ARE ROADS OF DIFFERENT TYPES. THE CFCC, AS USED IN THE TIGER/LINE(TM) FILES, IS A THREE-CHARACTER CODE. THE FIRST CHARACTER IS A LETTER DESCRIBIBG THE FEATURE CLASS ('A' FOR ROADS); THE SECOND CHARACTER IS A NUMBER DESCRIBING THE MAJOR CATEGORY; AND THE THIRD CHARACTER IS A NUMBER DESCRIBING THE MINOR CATEGORY. FEATURE CLASS 'A', ROADS DEFINITIONS APPLICABLE TO ROAD THE DEFINITION OF A DIVIDED HIGHWAY HAS BEEN THE SOURCE OF CONSIDERABLE DISCUSSION. EARLIER SPECIFICATIONS HAVE DEFINED A "DIVIDED" ROAD AS HAVING "... OPPOSING TRAFFIC LANES THAT ARE PHYSICALLY SEPARATED BY A MEDIAN STRIP NO LESS THAN 70 FEET WIDE IN FORMER GBF/DIME AREAS OR NO LESS THAN 200 FEET WIDE IN NON-GBF/DIME AREAS." THIS DEFINITION CAUSED CONFUSION IN THE PROPER CODING OF INTERSTATES HAVING NARROW MEDIANS. TO CLARIFY THE SITUATION, THE CENSUS BUREAU NOW USES THE TERM "DIVIDED" TO REFER TO A ROAD WITH OPPOSING TRAFFIC LANES SEPARATED BY ANY SIZE MEDIAN, AND "SEPARATED" TO REFER TO LANES THAT ARE REPRESENTED IN THE CENSUS TIGER DATA BASE AS TWO DISTINCT COMPLETE CHAINS. EARLIER OPERATIONS MAY HAVE DEPICTED WIDELY SEPARATED LANES AS A SINGLE LINE IN THE DATA BASE OR CREATED SEPARATE LINES WHEN THE MEDIAN WAS SMALL, DEPENDING ON THE AVAILABLE SOURCE USED DURING THE UPDATE. THE TERM "RAIL LINE IN CENTER" INDICATES THAT A RAIL LINE SHARES THE ROAD RIGHT-OF-WAY. THE RAIL LINE MAY FOLLOW THE CENTER OF THE ROAD OR BE DIRECTLY NEXT TO THE ROAD, REPRESENTATION IS DEPENDENT UPON THE AVAILABLE SOURCE USED DURING THE UPDATE. THE RAIL LINE CAN REPRESENT A RAILROAD, A STREET CAR LINE, OR OTHER CARLINE. ROAD WITH MAJOR CATEGORY UNKNOWN (A0_): SOURCE MATERIALS DO NOT ALLOW DETERMINATION OF THE MAJOR ROAD CATEGORY. THESE CODES SHOULD NOT, UNDER MOST CIRCUMSTANCES, BE USED SINCE THE SOURCE MATERIALS USUALLY PROVIDE ENOUGH INFORMATION TO DETERMINE THE MAJOR CATEGORY. CFCC DESCRIPTION A00 ROAD, MAJOR AND MINOR CATEGORIES UNKNOWN A01 ROAD, UNSEPARATED A02 ROAD, UNSEPARATED, IN TUNNEL A03 ROAD, UNSEPARATED, UNDERPASSING A04 ROAD, UNSEPARATED, WITH RAIL LINE IN CENTER A05 ROAD, SEPARATED A06 ROAD, SEPARATED, IN TUNNEL A07 ROAD, SEPARATED, UNDERPASSING A08 ROAD, SEPARATED, WITH RAIL LINE IN CENTER PRIMARY HIGHWAY WITH LIMITED ACCESS (A1_): THIS ROAD IS DISTINGUISHED BY THE PRESENCE OF INTER- CHANGES, ACCESS TO THE HIGHWAY IS BY WAY OF RAMPS, AND THERE ARE MULTIPLE LANES OF TRAFFIC. A ROAD IN THIS CATEGORY HAS THE OPPOSING TRAFFIC LANES "DIVIDED" BY A MEDIAN STRIP. INTERSTATE HIGHWAYS AND SOME TOLL HIGHWAYS ARE IN THIS MAJOR CATEGORY. THE TIGER/LINE(TM) FILES MAY DEPICT THE OPPOSING LANES OF A ROAD IN THIS CATEGORY AS TWO DISTINCT LINES; IN THIS CASE THE ROAD IS CALLED "SEPARATED." CFCC DESCRIPTION A10 PRIMARY ROAD WITH LIMITED ACCESS OR INTERSTATE HIGHWAY, MAJOR CATEGORY USED ALONE WHEN THE MINOR CATEGORY COULD NOT BE DETERMINED A11 PRIMARY ROAD WITH LIMITED ACCESS OR INTERSTATE HIGHWAY, UNSEPARATED A12 PRIMARY ROAD WITH LIMITED ACCESS OR INTERSTATE HIGHWAY, UNSEPARATED, IN TUNNEL A13 PRIMARY ROAD WITH LIMITED ACCESS OR INTERSTATE HIGHWAY, UNSEPARATED, UNDERPASSING A14 PRIMARY ROAD WITH LIMITED ACCESS OR INTERSTATE HIGHWAY, UNSEPARATED, WITH RAIL LINE IN CENTER A15 PRIMARY ROAD WITH LIMITED ACCESS OR INTERSTATE HIGHWAY, SEPARATED A16 PRIMARY ROAD WITH LIMITED ACCESS OR INTERSTATE HIGHWAY, SEPARATED, IN TUNNEL A17 PRIMARY ROAD WITH LIMITED ACCESS OR INTERSTATE HIGHWAY, SEPARATED, UNDERPASSING A18 PRIMARY ROAD WITH LIMITED ACCESS OR INTERSTATE HIGHWAY, SEPARATED, WITH RAIL LINE IN CENTER PRIMARY ROAD WITHOUT LIMITED ACCESS: A ROAD IN THIS MAJOR CATEGORY MUST BE HARD SURFACE, THAT IS, CONCRETE OR ASPHALT, AND MAY BE DIVIDED OR UNDIVIDED AND HAVE MULTI-LANE OR SINGLE LANE CHARACTERISTICS. THIS ROAD HAS INTERSECTIONS WITH OTHER ROADS, USUALLY CONTROLLED WITH TRAFFIC LIGHTS. THIS MAJOR CATEGORY INCLUDES NATIONALLY AND REGIONALLY IMPORTANT HIGHWAYS THAT DO NOT HAVE LIMITED ACCESS AS REQUIRED BY MAJOR CATEGORY A1. THUS, MAJOR CATEGORY A2 INCLUDES MOST U.S. AND STATE HIGHWAYS AND SOME COUNTY HIGHWAYS THAT CONNECT CITIES AND LARGER TOWNS. CFCC DESCRIPTION A20 PRIMARY ROAD WITHOUT LIMITED ACCESS, U.S. AND STATE HIGHWAY, MAJOR CATEGORY USED ALONE WHEN THE MINOR CATEGORY COULD NOT BE DETERMINED A21 PRIMARY ROAD WITHOUT LIMITED ACCESS, U.S. AND STATE HIGHWAYS, UNSEPARATED A22 PRIMARY ROAD WITHOUT LIMITED ACCESS, U.S. AND STATE HIGHWAYS, UNSEPARATED, IN TUNNEL A23 PRIMARY ROAD WITHOUT LIMITED ACCESS, U.S. AND STATE HIGHWAYS, UNSEPARATED, UNDERPASSING A24 PRIMARY ROAD WITHOUT LIMITED ACCESS, U.S. AND STATE HIGHWAYS, UNSEPARATED, WITH RAIL LINE IN CENTER A25 PRIMARY ROAD WITHOUT LIMITED ACCESS, U.S. AND STATE HIGHWAYS, SEPARATED A26 PRIMARY ROAD WITHOUT LIMITED ACCESS, U.S. AND STATE HIGHWAYS, SEPARATED, IN TUNNEL A27 PRIMARY ROAD WITHOUT LIMITED ACCESS, U.S. AND STATE HIGHWAYS, SEPARATED, UNDERPASSING A28 PRIMARY ROAD WITHOUT LIMITED ACCESS, U.S. AND STATE HIGHWAYS, SEPARATED, WITH RAIL LINE IN CENTER SECONDARY AND CONNECTING ROAD (A3_): A ROAD IN THIS MAJOR CATEGORY MUST BE HARD SURFACE, THAT IS, CONCRETE OR ASPHALT, USUALLY UNDIVIDED WITH SINGLE LANE CHARACTERISTICS. THIS ROAD HAS INTERSECTIONS WITH OTHER ROADS, CONTROLLED WITH TRAFFIC LIGHTS AND STOP SIGNS. THIS MAJOR CATEGORY INCLUDES STATE AND COUNTY HIGHWAYS THAT CONNECT SMALLER TOWNS, SUBDIVISIONS, AND NEIGHBORHOODS, THUS THE ROAD IS SMALLER THAN A ROAD IN MAJOR CATEGORY A2. THIS ROAD, USUALLY WITH A LOCAL NAME ALONG WITH A ROUTE NUMBER, INTERSECTS WITH MANY OTHER ROADS AND DRIVEWAYS. CFCC DESCRIPTION A30 SECONDARY AND CONNECTING ROAD, STATE AND COUNTY HIGHWAYS, MAJOR CATEGORY USED ALONE WHEN THE MINOR CATEGORY COULD NOT BE DETERMINED A31 SECONDARY AND CONNECTING ROAD, STATE AND COUNTY HIGHWAYS, UNSEPARATED A32 SECONDARY AND CONNECTING ROAD, STATE AND COUNTY HIGHWAYS, UNSEPARATED, IN TUNNEL A33 SECONDARY AND CONNECTING ROAD, STATE AND COUNTY HIGHWAYS, UNSEPARATED, UNDERPASSING A34 SECONDARY AND CONNECTING ROAD, STATE AND COUNTY HIGHWAYS, UNSEPARATED, WITH RAIL LINE IN CENTER A35 SECONDARY AND CONNECTING ROAD, STATE AND COUNTY HIGHWAYS, SEPARATED A36 SECONDARY AND CONNECTING ROAD, STATE AND COUNTY HIGHWAYS, SEPARATED, IN TUNNEL A37 SECONDARY AND CONNECTING ROAD, STATE AND COUNTY HIGHWAYS, SEPARATED, UNDERPASSING A38 SECONDARY AND CONNECTING ROAD, STATE AND COUNTY HIGHWAY, SEPARATED, WITH RAIL LINE IN CENTER LOCAL, NEIGHBORHOOD, AND RURAL ROADS (A4_): A ROAD IN THIS MAJOR CATEGORY IS USED FOR LOCAL TRAFFIC, USUALLY WITH A SINGLE LANE OF TRAFFIC IN EACH DIRECTION. IN AN URBAN AREA, THIS IS A NEIGHBORHOOD ROAD AND STREET THAT IS NOT A THOROUGHFARE BELONGING IN CATEGORIES A2 OR A3. IN A RURAL AREA, THIS IS A SHORT DISTANCE ROAD CONNECTING THE SMALLEST TOWNS; THE ROAD MAY OR MAY NOT HAVE A STATE OR COUNTY ROUTE NUMBER. IN ADDITION, THIS MAJOR CATEGORY INCLUDES SCENIC PARK ROADS, UNIMPROVED OR UNPAVED ROADS, AND INDUSTRIAL ROADS. MOST ROADS IN THE NATION ARE CLASSIFIED IN THIS MAJOR CATEGORY. CFCC DESCRIPTION A40 LOCAL, NEIGHBORHOOD, AND RURAL ROAD, CITY STREET, MAJOR CATEGORY USED ALONE WHEN THE MINOR CATEGORY COULD NOT BE DETERMINED A41 LOCAL, NEIGHBORHOOD, AND RURAL ROAD, CITY STREET, UNSEPARATED A42 LOCAL, NEIGHBORHOOD, AND RURAL ROAD, CITY STREET, UNSEPARATED, IN TUNNEL A43 LOCAL, NEIGHBORHOOD, AND RURAL ROAD, CITY STREET, UNSEPARATED, UNDERPASSING A44 LOCAL, NEIGHBORHOOD, AND RURAL ROAD, CITY STREET, UNSEPARATED, WITH RAIL LINE IN CENTER A45 LOCAL, NEIGHBORHOOD, AND RURAL ROAD, CITY STREET, SEPARATED A46 LOCAL, NEIGHBORHOOD, AND RURAL ROAD, CITY STREET, SEPARATED, IN TUNNEL A47 LOCAL, NEIGHBORHOOD, AND RURAL ROAD, CITY STREET, SEPARATED, UNDERPASSING A48 LOCAL, NEIGHBORHOOD, AND RURAL ROAD, CITY STREET, SEPARATED, WITH RAIL LINE IN CENTER VEHICULAR TRAIL: A ROAD IN THIS MAJOR CATEGORY IS USABLE ONLY BY FOUR- WHEEL DRIVE VEHICLES AND IS USUALLY A ONE LANE, DIRT TRAIL. THE ROAD IS FOUND ALMOST EXCLUSIVELY IN A VERY RURAL AREA, SOMETIMES THE ROAD IS CALLED A FIRE ROAD OR LOGGING ROAD AND MAY INCLUDE AN ABANDONED RAILROAD GRADE WHERE THE TRACKS HAVE BEEN REMOVED. MINOR, UNPAVED ROADS USABLE BY ORDINARY CARS AND TRUCKS BELONG IN MAJOR CATEGORY A4. CFCC DESCRIPTION A50 VEHICULAR TRAIL, ROAD PASSABLE ONLY BY FOUR- WHEEL DRIVE (4WD) VEHICLE, MAJOR CATEGORY USED ALONE WHEN THE MINOR CATEGORY COULD NOT BE DETERMINED A51 VEHICULAR TRAIL, ROAD PASSABLE ONLY BY 4WD VEHICLE, UNSEPARATED A52 VEHICULAR TRAIL, ROAD PASSABLE ONLY BY 4WD VEHICLE, UNSEPARATED, IN TUNNEL A53 VEHICULAR TRAIL, ROAD PASSABLE ONLY BY 4WD VEHICLE, UNSEPARATED, UNDERPASSING ROAD WITH SPECIAL CHARACTERISTICS (A6_): A ROAD, PORTION OF A ROAD, INTERSECTION OF A ROAD, OR THE ENDS OF A ROAD THAT ARE PARTS OF THE VEHICULAR HIGHWAY SYSTEM THAT HAVE SEPARATELY IDENTIFIABLE CHARACTERISTICS. CFCC DESCRIPTION A60 ROAD WITH CHARACTERISTIC UNSPECIFIED, MAJOR CATEGORY USED ALONE WHEN THE MINOR CATEGORY COULD NOT BE DETERMINED A61 CUL-DE-SAC, THE CLOSED END OF A ROAD THAT FORMS A LOOP OR TURN AROUND (THE NODE SYMBOL THAT APPEARS ON SOME CENSUS MAPS IS NOT INCLUDED IN THE TIGER/LINE(TM) FILES) A62 TRAFFIC CIRCLE, THE PORTION OF A ROAD OR INTER- SECTION OF ROADS THAT FORM A ROUNDABOUT (THE NODE SYMBOL THAT APPEARS ON SOME CENSUS MAPS IS NOT INCLUDED IN THE TIGER/LINE(TM) FILES) A63 ACCESS RAMP, THE PORTION OF A ROAD THAT FORMS A CLOVERLEAF OR LIMITED ACCESS INTERCHANGE (THE NODE SYMBOL THAT APPEARS ON SOME CENSUS MAPS IS NOT INCLUDED IN THE TIGER/LINE(TM) FILES) A64 SERVICE DRIVE, THE ROAD OR PORTION OF A ROAD THAT PROVIDES ACCESS TO BUSINESSES, FACILITIES, AND REST AREAS ALONG A LIMITED ACCESS HIGHWAY, THIS FRONTAGE ROAD MAY INTERSECT OTHER ROADS AND BE NAMED A65 FERRY CROSSING, THE PORTION OF A ROAD OVER WATER THAT CONSISTS OF SHIPS, CARRYING AUTOMOBILES, CONNECTING ROADS ON OPPOSITE SHORES ROAD AS OTHER THOROUGHFARE: A ROAD THAT IS NOT PART OF THE VEHICULAR HIGHWAY SYSTEM. THIS ROAD IS USED BY BICYCLISTS OR PEDESTRIANS AND IS TPICALLY INACCESSIBLE TO MAINSTREAM MOTOR TRAFFIC EXCEPT BY SERVICE VEHICLES. A STAIR AND WALKWAY MAY FOLLOW A ROAD RIGHT-OF-WAY AND BE NAMED AS IF IT WERE A ROAD. THIS MAJOR CATEGORY INCLUDES FOOT AND HIKING TRAILS LOCATED ON PARK AND FOREST LAND. CFCC DESCRIPTION A70 OTHER THOROUGHFARE, MAJOR CATEGORY USED ALONE WHEN THE MINOR CATEGORY COULD NOT BE DETERMINED A71 WALKWAY, NEARLY LEVEL ROAD FOR PEDESTRIANS, USUALLY UNNAMED A72 STAIRWAY, STEPPED ROAD FOR PEDESTRIANS, USUALLY UNNAMED A73 ALLEY, ROAD FOR SERVICE VEHICLES, USUALLY UNNAMED, LOCATED AT THE REAR OF BUILDINGS AND PROPERTY Type: C Length: 3 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: SEE DESCRIPTION ABOVE 03. Item: FIPS Description: FEDERAL CODE FOR COUNTIES Type: C Length: 3 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: 025 DADE COUNTY 087 MONROE COUNTY 04. Item: PREFIX Description: PREFIX Type: C Length: 2 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: E, N, NE, NW, S, SE, SW, W 05. Item: NAME Description: STREET NAME Type: C Length: 30 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: VARIES 06. Item: TYPE Description: STREET TYPE Type: C Length: 4 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: AL, AVE, BLVD, BRDG, BYP, C, CIR, COVE, CRES, CSWY, CT, CTR, DR, EXWY, HWY, LANE, LOOP, MALL, PARK, PASS, PATH, PKWY, PL, PLZ, PT, ROAD, ROW, SQ, ST, TER, TPKE, TRL, WALK, WAY 07. Item: LEGEND Description: AN ATTRIBUTE USED TO DISPLAY US ROUTE 1 SEPARATELY FROM ALL OTHER ROADS Type: C Length: 2 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: US1, OTHER ************************************ GENERAL INFORMATION - Protected Areas Name: Prot_Areas Title: Protected Areas within the Florida Keys National Marine Sanctuary Type: POLYGON Geographic Extent: southern Florida Creation Date: 1998 Projection: GEOGRAPHIC COORDINATES Units: DECIMAL DEGREES Spheroid: GRS1980 Precision: SINGLE Datum: NAD83 Accuracy: UNKNOWN Description-Abstract: This is a polygon geography showing the extents and locations of 23 special protected areas within the Florida Keys National Marine Sanctuary. DATA SOURCE INFORMATION Organization: NOAA Contact: Steve Rohmann Address: 1305 East West Highway, Silver Spring, MD 20910 Phone Number: 301/713-3000x137 Scale: 1:80000 Projection: geographic coordinates Precision: UNKNOWN Datum: NAD83 Accuracy: UNKNOWN Source Format: NOS nautical chart DISTRIBUTION INFORMATION QA/QC Status: COMPLETE Distribution Status: AVAILABLE Data Format: ArcView shapefile Contact: Steve Rohmann Address: 1305 East West Highway, Silver Spring, MD 20910 Phone Number: 301/713-3000x137 DATA DICTIONARY .PAT FILE 01. Item: NAME Description: NAME ASSIGNED TO EACH SPECIAL PROTECTED AREA Type: Character Length: 50 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: varies 02. Item: INDEX Description: Attribute used within ArcView to index what region within the Florida Keys the protected area lies Type: Character Length: 1 Decimals: 0 Format: N/A Mandatory: N Default Values: N/A Item Values: A; B; C; D ************************************ GENERAL INFORMATION - Florida Keys National Marine Sanctuary boundary Name: FKNMS Title: boundary of the Florida Keys National Marine Sanctuary Type: POLYGON Geographic Extent: southern Florida Creation Date: 1996 Projection: GEOGRAPHIC COORDINATES Units: DECIMAL DEGREES Spheroid: GRS1980 Precision: SINGLE Datum: NAD83 Accuracy: UNKNOWN Description-Abstract: This is a polygon showing the extent of the Florida Keys National Marine Sanctuary. DATA SOURCE INFORMATION Organization: NOAA Contact: Christine Taylor Address: 1305 East West Highway, Silver Spring, MD 20910 Phone Number: 301/713-7277 Scale: 1:80000 Projection: geographic coordinates Precision: UNKNOWN Datum: NAD83 Accuracy: UNKNOWN Source Format: NOS nautical chart DISTRIBUTION INFORMATION QA/QC Status: COMPLETE Distribution Status: AVAILABLE Data Format: ArcView shapefile Contact: Steve Rohmann Address: 1305 East West Highway, Silver Spring, MD 20910 Phone Number: 301/713-3000x137 DATA DICTIONARY - None needed for this geography ************************************ GENERAL INFORMATION - Geographic Place Names Name: Place Names Title: The names of places found within the Florida Keys region Type: POINT Geographic Extent: southern Florida Creation Date: 1998 Projection: GEOGRAPHIC COORDINATES Units: DECIMAL DEGREES Spheroid: GRS1980 Precision: SINGLE Datum: NAD83 Accuracy: UNKNOWN Description-Abstract: This is a point geography showing the names of land masses, water bodies, and other geographic features within the Florida Keys region. DATA SOURCE INFORMATION Organization: UNKNOWN Contact: Steve Rohmann Address: 1305 East West Highway, Silver Spring, MD 20910 Phone Number: 301/713-3000x137 Scale: 1:80000 Projection: geographic coordinates Precision: UNKNOWN Datum: NAD83 Accuracy: UNKNOWN Source Format: NOS nautical chart DISTRIBUTION INFORMATION QA/QC Status: COMPLETE Distribution Status: AVAILABLE Data Format: ArcView shapefile Contact: Steve Rohmann Address: 1305 East West Highway, Silver Spring, MD 20910 Phone Number: 301/713-3000x137 DATA DICTIONARY - None needed for this geography. *******