FLORIDA GEOGRAPHIC DATA LIBRARY DOCUMENTATION
VERSION 2007

TITLE: FLORIDA EXTENT OF THE 1,000 METER, UNITED STATES NATIONAL GRID 

Geodataset Name:       USNG_FL_1K
Geodataset Type:       SHAPEFILE
Geodataset Feature:    Polygon
Feature Count:         363506
GENERAL DESCRIPTION:
This layer represents a 1,000 by 1,000 meter United States National Grid (USNG) for Florida. The USNG is an alpha-numeric reference system based on the UTM coordinate system and is similar to the Military Grid Reference System. Use of the USNG ensures a uniform grid mapping and positional reporting system for search and rescue, emergency planning, response, and recovery. 
DATA SOURCE(S):                    University of Florida GeoPlan Center
SCALE OF ORIGINAL SOURCE MAPS:     N/A
DATE OF AUTOMATION OF SOURCE:      20070426
GEODATASET EXTENT:                 State of Florida

FEATURE ATTRIBUTE TABLES: 

Datafile Name: USNG_FL_1K.DBF
ITEM NAME WIDTH TYPE N. DECIMAL DEGREES
OBJECTID
4 OID ---
X_LWRLFT
19 Number 11
Y_LWRLFT
19 Number 11
GRID100K
2 String ---
GRID10K
3 String ---
GRID1000M
5 String ---
LABEL
7 String ---
DESCRIPT
7 String ---
FGDLAQDATE
8 Date ---
AUTOID
6 Number ---
SHAPE
4 Geometry ---
SHAPE.AREA
0 Double ---
SHAPE.LEN
0 Double ---

FEATURE ATTRIBUTE TABLES CODES AND VALUES:

Item

Item Description





OBJECTID

Internal feature number.
















X_LWRLFT

X coordinate of the lower left hand corner of the polygon.
















Y_LWRLFT

Y coordinate of the lower left hand corner of the polygon.
















GRID100K

100,000-meter Square Identification; for regional areas, identified by two letter values.
















GRID10K

10,000-meter grid label for the local area.
















GRID1000M

1,000-meter grid label for the local area.
















LABEL

Concatenated 100K grid label and 1000 meter grid label.
















DESCRIPT

Based on LABEL.
















FGDLAQDATE

The date FGDL acquired the data from the source.
















AUTOID

GeoPlan internal feature identification number.
















SHAPE

Feature geometry.
















SHAPE.AREA

Area in meters
















SHAPE.LEN

Perimeter in meters




























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.













How to Read a United States National Grid (USNG) Spatial Address
http://www.fgdc.gov/usng/how-to-read-usng/index_html
---------------------------------------------------------------

The USNG is an alpha-numeric reference system that overlays the UTM 
coordinate system.  A USNG spatial address is broken down into three parts, the;
 - Grid Zone Designation; for a world-wide unique address.
 - 100,000-meter Square Identification; for regional areas.
 - Grid Coordinates; for local areas. 

4 digits - 2306 - locates a point with a precision of 1,000-meters (a neighborhood size area).
6 digits - 234064 - locates a point with a precision of 100-meters (a soccer field size area).
8 digits - 23480647 - locates a point with a precision of 10-meters (the size of a  modest home).
10 digits - 2348306479 - locates a point with a precision of 1-meter (within a parking spot).

To review, we can see a complete US National Grid spatial address 
contains three parts as we drill down to a unique location,  18S UJ 23480647
 - Grid Zone Designation (i.e. 18S).
 - 100,000-meter Square Identification (i.e. UJ ).
 - Grid coordinates of some even number of digits ranging from 2 to 10 
(i.e. 23480647  In this case, eight digits identify a place of about the size 
of a modest home.).  You always read right, then up when plotting coordinates. 

A spatial address is customarily written as a single string of values.  
Note how the horizontal datum (NAD 83) has been included: 
USNG: 18SUJ23480647 (NAD 83)


Floridadisaster.org
---------------------------------------------------------------
In an effort to standardize maps in Florida for both emergency and 
other operations, the State Fire Marshal, as the coordinating agency 
for search and rescue under the State Comprehensive Emergency 
Management Plan, and the Division of Emergency Management are 
embarking on a program to adopt the US National Grid (USNG) as the 
standard in Florida. This project will ensure a uniform grid mapping 
system across cities and counties in Florida, and will match the system 
used by the National Guard, the US Coast Guard and the US military 
when they are deployed into our state.

Florida s unique geography of miles of coastlines, multiple river corridors, 
and large watersheds make the use of the common 
Township/Range/Section grid (PLSS) all but impossible except for 
a handful of inland counties. As the grid approaches wetlands, river 
corridors and the coast line, sections become irregular in shape and 
can be significantly larger than the typical square mile, which is too 
large to accommodate the needs of ground crews.

Adoption of a national grid system has been identified as  critical  
in a number of after action reports, investigations and studies 
dating as far back as Hurricane Andrew. FEMA, DHS, the National 
GeoSpatial Intelligence Agency, and the Federal Geographic Data 
Committee all promote the adoption of the USNG. 

Grid cell values are unique and sequentially numbered.















The grid serves as a common means for providing locational information in 
relation to USNG coordinates.















The grid's horizontal accuracy was mathematically generated and is 
accurate to the internal precision of ArcGIS 9.2 coordinates.















The grid's vertical accuracy was mathematically generated and is 
accurate to the internal precision of ArcGIS 9.2 coordinates.















THE DATA INCLUDED IN FGDL ARE 'AS IS' AND SHOULD NOT BE CONSTRUED
AS LEGALLY BINDING. 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: 






Florida State Emergency Response Team
United States National Grid
http://floridadisaster.org/gis/usng/

Guidelines for Building US National Grid Polygons with ArcGIS
http://floridadisaster.org/gis/usng/Documents/build_usng_polygons.pdf









DATA LINEAGE SUMMARY: 








The University of Florida GeoPlan Center produced a grid in an ArcMap 
data viewer with the coordinate system set to NAD_83_UTM_Zone_17N. 
A 1,000-meter by 1,000 grid was generated, using the XTools Fishnet function 
and covering the area of Florida contained within the UTM 17 N zone. 
Overlap was included for use in neighboring areas.

Next the XTools Add XY function was used to produce X and Y coordinates 
for each polygon.

Added fields: X_LWRLFT, Y_LWRLFT, GRID100K, GRID10K, GRID1000M, 
LABEL, DESCRIPT, FGDLAQDATE, and AUTOID.

Calculated the AUTOID field as follows;
[FID] + 1

Created Centroids for the 1000M Grid and spatially joined it to the existing 
usng_fl_10k_utm17.shp Grid.

Joined the Centroids with the 10K Grid information back to the 1000M Grid, 
via a table join based on AUTOID.

Calculated the GRID100K field based on the joined GRID100K field from the Centroids.

Calculated the GRID10K field based on the joined GRID10K field from the Centroids.

Calculate X_LWRLFT and Y_LWRLFT values as follows;
Round ( [XCOORD] - 500, 0 ) 
Round ( [YCOORD] - 500, 0 )
After these calculations, the XCOORD and YCOORD fields may be deleted.

Calculate GRID1000M as follows;
Mid ( [X_LWRLFT] , 2, 2 ) + " " + Mid ( [Y_LWRLFT] , 3 ,2 )

Calculate LABEL as follows;
[GRID100K] + " " + Mid ( [X_LWRLFT] , 2, 2 ) + Mid ( [Y_LWRLFT] , 3 ,2 )

Calculated DESCRIPT based on LABEL.

After field calculations were completed the join was removed.

For more information on field calculations please see 
Guidelines for Building US National Grid Polygons with ArcGIS
http://floridadisaster.org/gis/usng/Documents/build_usng_polygons.pdf
Process Date: 20070426


The University of Florida GeoPlan Center produced a grid in an ArcMap 
data viewer with the coordinate system set to NAD_83_UTM_Zone_16N. 
A 1,000-meter by 1,000 grid was generated, using the XTools Fishnet function 
and covering the area of Florida contained within the UTM 16 N zone. 
Overlap was included for use in neighboring areas.

Next the XTools Add XY function was used to produce X and Y coordinates 
for each polygon.

Added fields: X_LWRLFT, Y_LWRLFT, GRID100K, GRID10K, GRID1000M, 
LABEL, DESCRIPT, FGDLAQDATE, and AUTOID.

Calculated the AUTOID field as follows;
[FID] + 250,001

Created Centroids for the 1000M Grid and spatially joined it to the existing 
usng_fl_10k_utm16.shp Grid.

Joined the Centroids with the 10K Grid information back to the 1000M Grid, 
via a table join based on AUTOID.

Calculated the GRID100K field based on the joined GRID100K field from the Centroids.

Calculated the GRID10K field based on the joined GRID10K field from the Centroids.

Calculate X_LWRLFT and Y_LWRLFT values as follows;
Round ( [XCOORD] - 500, 0 ) 
Round ( [YCOORD] - 500, 0 )
After these calculations, the XCOORD and YCOORD fields may be deleted.

Calculate GRID1000M as follows;
Mid ( [X_LWRLFT] , 2, 2 ) + " " + Mid ( [Y_LWRLFT] , 3 ,2 )

Calculate LABEL as follows;
[GRID100K] + " " + Mid ( [X_LWRLFT] , 2, 2 ) + Mid ( [Y_LWRLFT] , 3 ,2 )

Calculated DESCRIPT based on LABEL.

After field calculations were completed the join was removed.

For more information on field calculations please see 
Guidelines for Building US National Grid Polygons with ArcGIS
http://floridadisaster.org/gis/usng/Documents/build_usng_polygons.pdf
Process Date: 20070426


The University of Florida GeoPlan Center then brought the two UTM 1K 
Grids into an ArcMap data viewer with the coordinate system set to FGDL Albers.

Next the UTM Zone 17N and UTM Zone 16N shapefiles were 
reprojected to the FGDL Albers projection (NAD83 Albers HPGH).

Next selections were taken from each UTM zone where as they did not 
interest each other.  These two selections were then appended together 
to create a statewide layer where areas containing the over lap contained 
no data.

Next each zone was selected for where features overlaped each zone 
and these overlap features were exported for each shapefile.  

Each exported zones over lap features were then erased, this erase 
was base on features falling outside their designated 100K grid, this 
erase was based on the usgn_fl_100k.shp

Next the remaining parts of the two erased zone shapefiles were 
appended back to the statewide 1K layer creating a continuous 
statewide 1K layer.
Process Date: 20070426









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 ARCH BLDG
Gainesville, FL
32611



www.fgdl.org
data@fgdl.org










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