FLORIDA GEOGRAPHIC DATA LIBRARY DOCUMENTATION

TITLE: FLORIDA DIGITAL ELEVATION MODEL (DEM) MOSAIC - 5-METER CELL SIZE - ELEVATION UNITS METERS

Geodataset Name:       FLIDAR_MOSAIC_M
Geodataset Type:       RASTER
Geodataset Feature:    5-METER CELL
Feature Count:         108
GENERAL DESCRIPTION:
This data set represents a five meter cell size Digital Elevation Model (DEM) covering the State of Florida. The elevation units are expressed in meters. The vertical datum is NAVD88, meters, and the projection is Albers Equal Area Conic HARN, meters. The DEM was created by mosaicking data from 4 different sources, with the following order of priority: 1) NWFWMD District DEM 2) FLIDAR Coastal DEM 3) Statewide FWC DEM 4) Contour Derived DEM.
DATA SOURCE(S):                    University of Florida GeoPlan Center
SCALE OF ORIGINAL SOURCE MAPS:     N/A
GEODATASET EXTENT:                 State of Florida
PUBLICATION DATE: 201301 TIME PERIOD OF CONTENT: 2012 DOWNLOAD LINK: http://www.fgdl.org/metadataexplorer/explorer.jsp

FEATURE ATTRIBUTE TABLES:

Datafile Name: FLIDAR_MOSAIC_M
ITEM NAME WIDTH TYPE
OBJECTID
4 OID
Value
4 Integer
Count
8 Double

FEATURE ATTRIBUTE TABLES CODES AND VALUES:

Item
Item Description
OBJECTID Internal feature number.

Value Elevation in meters.

Count Count of cells with the same elevation value.


USER NOTES:
This data is provided 'as is'. GeoPlan relied on the integrity
of the original data layer's topology
This data is provided 'as is' by GeoPlan and is complete to our
knowledge.
GeoPlan relied on the integrity of the attribute information within
the original data.

The data was created to serve as base information for use in GIS systems
for a variety of planning and analytical purposes.

This data is provided 'as is' and its horizontal positional accuracy
has not been verified by GeoPlan

This data is provided 'as is' and its vertical positional accuracy
has not been verified by GeoPlan

None

The Florida Geographic Data Library is a collection of Geospatial Data
compiled by the University of Florida GeoPlan Center with support from
the Florida Department of Transportation. GIS data available in FGDL is
collected from various state, federal, and other agencies (data sources)
who are data stewards, producers, or publishers. The data available in
FGDL may not be the most current version of the data offered by the
data source. University of Florida GeoPlan Center makes no guarantees
about the currentness of the data and suggests that data users check
with the data source to see if more recent versions of the data exist.

Furthermore, the GIS data available in the FGDL are provided 'as is'.
The University of Florida GeoPlan Center makes no warranties, guaranties
or representations as to the truth, accuracy or completeness of the data
provided by the data sources. The University of Florida GeoPlan Center
makes no representations or warranties about the quality or suitability
of the materials, either expressly or implied, including but not limited
to any implied warranties of merchantability, fitness for a particular
purpose, or non-infringement. The University of Florida GeoPlan Center
shall not be liable for any damages suffered as a result of using,
modifying, contributing or distributing the materials.

A note about data scale: 

Scale is an important factor in data usage.  Certain scale datasets
are not suitable for some project, analysis, or modeling 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.
1:125000 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 analysis. 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 webpage at:
http://geoplan.ufl.edu/education.html

REFERENCES:


DATA LINEAGE SUMMARY:
The following source DEMs were used to create a statewide DEM. The sources are 
listed in order of priority:

1) Northwest Florida Water Management District (NWFWMD) DEM 
     description: Received from NWFWMD district in 2012. This DEM was created
      from a variety of different sources, metadata from each source used by 
      NWFWMD is included with the FGDL download and is located in the following 
      folder: ...\meta\nwfwmd
     cell size: 2, 2 (meters)
     pixel type: floating point
     elevation units: feet
     elevation datum: NAVD88
     
2) NOAA FLIDAR Coastal DEM 
      description: This DEM is based on coastal Lidar data sourced from the NOAA 
       Coastal Services Center. Metadata from each source used by NOAA is included 
       with the FGDL download and is located in the following folder: ...\meta\noaa
      cell size: 5.4329891, 5.4329891 (meters)
      pixel type: unsigned integer
      elevation units: inches
      elevation datum: NAVD88
      
3) Florida Fish and Wildlife Conservation Commission (FWC) Florida Statewide 5-Meter DEM 
      description: this is a statewide DEM that has some gaps. The DEM was 
       received from FWC in 2012. Note: the source vertical datum was NGVD29, 
       which was converted to NAVD88. Original metadata for this source DEM is 
       included with the FGDL download and is located in the following folder: 
       ...\meta\fwc
      cell size: 5.4329891, 5.4329891 (meters)
      pixel type: floating point
      elevation units: meters
      elevation datum: NGVD29
  
4) Contour Derived DEM
      description: This DEM is based on 2ft contours from the coastal LiDAR 
       project. The biggest portion of this source data is around Lake Okeechobee, 
       where data was from Merrick. For more information on the contour data please 
       see FGDL layers prefixed with "TOPO2FT_".
      cell size: 5.4329891, 5.4329891 (meters)
      pixel type: unsigned integer
      elevation units: inches
      elevation datum: NAVD88

=============================================================================

Processing steps for statewide DEM: 20121018

Using ArcGIS 10.0, the following process was executed to create the statewide 
DEM. 

During any command that was executed the following environment settings were used:
  set snap raster as NOAA  FLIDAR Coastal DEM
  set cell size = NOAA FLIDAR Coastal DEM  (5.4329891, 5.4329891)


-Copy Raster command was executed to resample NWFWMD District DEM from 2 
meter cells to 5 meter cells. Converted raster from floating point to integer and 
changed units to inches.
-Mosaic to New Raster command executed to combine the NWFWMD District 
DEM and  the FLIDAR Coastal DEM. The NWFWMD District DEM was given 
priority.
-Used Raster Calculator to convert the FWC DEM to integer and used the 
 following formula (("fwc_mos88" * 39.3696) + 0.5) to convert to inches 
 (please note: the 0.5 was added to account for ArcMaps rounding rules)
-Mosaic to New Raster command executed to combine the previous mosaic with 
 processed FWC DEM. Priority was given to the mosaic.
-Used Contour to DEM tool to create a DEM of the area where gaps existed. 
 The 2ft contours from the coastal LiDAR project were used.
-Mosaic to New Raster command executed to combine previous mosaic with 
 contour derived DEM, priority was given to previous mosaic.
-Set all negative (-302 to -1) values to null
-Created a water grid using water areas from 5 Water Management District Landuse/Landcover layers where:
   - LEVEL1='WATER'
   - SFWMD where FLUCCS = 1660 (HOLDING PONDS)
   - SRWMD where FLUCCS = 8160 (CANALS AND LOCKS)
   - NWFWMD where FLUCCS = 8160 (CANALS AND LOCKS)
-Reclassed all water grid values to -1
-Mosaic to New Raster command executed to combine the water grid and previous mosaic.
-The final output raster feature class was named flidar_mosaic_in and was 
 copied into a 9.3.1 file geodatabase with the following properties:
   pixel units: inches
   single band
   16bit signed integer
   cell size: 5.4329891, 5.4329891 meters
   projection: Albers HPGN
   vertical datum: NAVD88
-The final product (flidar_mosaic_in) was converted to feet, centimeters, and meters 
and named flidar_mosaic_ft, flidar_mosaic_cm, flidar_mosaic_m

Notes:
-The Northwest Florida Water Management District DEM was considered the 
highest order data source based on a nominal 2-meter horizontal resolution, which 
is  closer to the native resolution of the original coastal Lidar data collection 
than all other sources used in this mosaic.  Vertical values for the NWFWMD DEM 
are recorded in feet, while the vertical accuracy for the original Lidar data 
collection is reported in inches.  Therefore, the decision was made to 
standardize all data sets and construct the mosaic with inches as the vertical 
unit. 
-No smoothing was done when executing mosaic commands. In some areas where 
DEMs  come together there are discrepancies, typically these differences are 
minimal and can't be seen at all when zooming out beyond 1:240K.
-A feature class representing the source data used for the DEM can be found in 
 the same file geodatabase as the DEM and called flidar_mosaic_source.
-The processing for this data was done primarily using ArcGIS Desktop 10.0, all 
data is delivered in a 9.3.1 compliant File GeoDatabase.
Process Date: 201021018

Metadata imported. Process Date: 20130117
MAP PROJECTION PARAMETERS:

Projection                          ALBERS
Datum                               HPGN
Units                               METERS
Spheroid                            GRS1980
1st Standard Parallel               24  0  0.000
2nd Standard Parallel               31 30  0.000
Central Meridian                   -84 00  0.000
Latitude of Projection's Origin     24  0  0.000
False Easting (meters)              400000.00000
False Northing (meters)             0.00000

DATA SOURCE CONTACT (S):

Name:
Abbr. Name:
Address:


Phone:

Web site:
E-mail:
Contact Person:
         Phone:
        E-mail:
University of Florida GeoPlan Center
GeoPlan
431 Architecture Building
Gainesville, FL
32611
n/a

http://www.fgdl.org/metadataexplorer/explorer.jsp Russell Watkins

FGDL CONTACT:
Name:                   FLORIDA GEOGRAPHIC DATA LIBRARY
Abbr. Name:             FGDL
Address:                Florida Geographic Data Library
                        431 Architecture Building
                        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