Northern
California Census Block Groups Metadata
GEODATASET NAME: NCA_BLKGRPA83
IDENTIFICATION INFORMATION
Description:
Northern California Pilot Study Area Census Block Groups.
Abstract:
Derived from the ESRI California and Oregon Census Block Groups dataset. This
dataset is the actual census block groups as defined by the Bureau of the Census.
Data Type:
Coverage, polygon
Data Originator:
Environmental Systems Research Institute Inc. (ESRI)
380 New York Street
Redlands CA, 92373-8100
(909) 793-2853
www.esri.com
Data Processor:
Ed Evanson
Lockheed Martin Environmental Services
1050 E. Flamingo Road, Suite E120
Las Vegas, NV 89119
(702)897-3208
eevanson@lmepo.com
Data Provider:
Dan Heggem
U.S. Environmental Protection Agency NERL
P.O. Box 93478
Las Vegas, NV 89193-3478
(702)798-2278
heggem.daniel@epa.gov
Keywords:
Northern California, Pilot Study Area, Census Block Groups
Version:
N/A
Status:
Interim
Revision Number:
0
Series Name:
Online Link (URL):
Time Period of Content:
Use Constraints:
None. Acknowledgment of the originating agencies would be appreciated in
products derived from these data.
Purpose:
Northern California data browser
Date of metadata entry/update:
09/06/2001
No Publication Information Available
No File Security Information Available
DATA QUALITY INFORMATION
Cloud Cover:
Not applicable
Software:
Arc/Info 7.2
Operating System:
Unix
Path Name:
/gis/wemap/nca/census_blkgrp
Logical Consistency Report:
Not presently available
Completeness Report:
Not presently available
Horizontal Positional Accuracy:
Not presently available
Vertical Positional Accuracy:
Not presently available
Attribute Accuracy:
Not presently available
Procedures:
Using Arcview, ESRI Census Block Groups for the state of California and Oregon
were merged
and clipped to the Northern California boundary. The resulting Arcview
Shapefile was converted to an Arc/Info coverage and projected to region 9 Albers
projection.
Reviews Applied to Data
Lockheed Martin Environmental Services internal review
Related Spatial Data Files:
All geodatasets with nca_ prefix.
Other References Cited:
Notes:
Update Frequency:
As needed
SPATIAL REFERENCE INFORMATION
Description of DOUBLE precision coverage nca_blkgrpa83
FEATURE CLASSES
Number of Attribute Spatial
Feature Class Subclass Features data (bytes) Index? Topology?
------------- -------- --------- ------------ ------- ---------
ARCS 2129
POLYGONS 738 324 Yes
NODES 1401
SECONDARY FEATURES
Tics 4
Arc Segments 113090
Polygon Labels 737
TOLERANCES
Fuzzy = 51.383 V Dangle = 0.000 N
COVERAGE BOUNDARY
Xmin = -649332.863 Xmax = -314106.531
Ymin = 4044266.250 Ymax = 4544241.500
STATUS
The coverage has not been Edited since the last BUILD or CLEAN.
COORDINATE SYSTEM DESCRIPTION
Projection ALBERS
Datum NAD83
Units METERS Spheroid GRS1980
Parameters:
1st standard parallel 33 15 0.000
2nd standard parallel 40 15 0.000
central meridian -116 45 0.00
latitude of projection's origin 0 0 0.000
false easting (meters) 0.00000
false northing (meters) 0.00000
ENTITY AND ATTRIBUTE INFORMATION
Annotation Name:
ATTRIBUTE LISTING FOR: nca_blkgrpa83.pat
COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME INDEXED?
1 AREA 8 18 F 5 -
9 PERIMETER 8 18 F 5 -
17 NCA_BLKGRPA83# 4 5 B - -
21 NCA_BLKGRPA83-ID 4 5 B - -
25 BKG_KEY 12 12 C - -
37 POP1990 8 9 F 0 -
45 POP90_SQMI 8 10 F 1 -
53 HOUSEHOLDS 8 9 F 0 -
61 MALES 8 9 F 0 -
69 FEMALES 8 9 F 0 -
77 WHITE 8 9 F 0 -
85 BLACK 8 8 F 0 -
93 AMERI_ES 4 7 B - -
97 ASIAN_PI 8 8 F 0 -
105 OTHER 8 8 F 0 -
113 HISPANIC 8 8 F 0 -
121 AGE_UNDER5 8 8 F 0 -
129 AGE_5_17 8 8 F 0 -
137 AGE_18_29 8 8 F 0 -
145 AGE_30_49 8 8 F 0 -
153 AGE_50_64 8 8 F 0 -
161 AGE_65_UP 8 8 F 0 -
169 NEVERMARRY 8 8 F 0 -
177 MARRIED 8 9 F 0 -
185 SEPARATED 4 7 B - -
189 WIDOWED 8 8 F 0 -
197 DIVORCED 8 8 F 0 -
205 HSEHLD_1_M 8 8 F 0 -
213 HSEHLD_1_F 8 8 F 0 -
221 MARHH_CHD 8 8 F 0 -
229 MARHH_NO_C 8 8 F 0 -
237 MHH_CHILD 4 7 B - -
241 FHH_CHILD 4 7 B - -
245 HSE_UNITS 8 9 F 0 -
253 VACANT 4 7 B - -
257 OWNER_OCC 8 8 F 0 -
265 RENTER_OCC 8 8 F 0 -
273 MEDIAN_VAL 4 7 B - -
277 MEDIANRENT 4 4 B - -
281 UNITS_1DET 8 8 F 0 -
289 UNITS_1ATT 4 7 B - -
293 UNITS2 4 7 B - -
297 UNITS3_9 8 8 F 0 -
305 UNITS10_49 8 8 F 0 -
313 UNITS50_UP 8 8 F 0 -
321 MOBILEHOME 4 7 B - -
METADATA REFERENCE SECTION
FGDC Content Standards for Digital Geospatial Metadata
FGDC Standards Version 6/98 / metadata.aml ver. 1.3 5/21/99
SUPPLEMENTAL METADATA (where available)
Census Block Groups: The U.S. Census Block Groups data set represents a
collection of ESRI shapefiles that depicts the census block groups for an
area. These data sets are the actual census block groups as defined by the
Bureau of the Census. Census block groups are geographic entities within the
same census tract or BNA having the same first digit of their three-digit
block numbers. Block groups never cross the boundaries of county subdivisions,
places, urbanized areas, voting districts, congressional districts, and
American Indian/Alaska Native areas. Block groups generally contain between
250 and 550 housing units. Each block group usually covers a contiguous area.
Each census tract/BNA contains at least one block group. Block groups are
uniquely numbered within each census tract/BNA.