Geographic Projection
Files for available water capacity
Files for available water capacity
Data set reference code -- 1996-0089
To accommodate users with a variety of GIS software, the data giving the
available water capacity are available in several different formats.
The files needed by each of the types of user below are described
separately.
NOTE -- Most of these files have been compressed using
the GNU gzip program, as indicated by the .gz file
extension. Users who do not have access to the gunzip
decompression program can request that files be uncompressed prior to
transfer via ftp. In some cases, however, the uncompressed file may be
very much larger than the compressed version, greatly increasing file
transfer time.
The orginal STATSGO mapunits for the 48 states have been merged into a
single Arc/Info polygon (vector) coverage. The available water capacity
for each mapunit is given by the INFO table MU_AWC, which may be RELATEd
to the mapunit coverage using "MUID" as the relate item. The needed
files are
-
mu_poly.e00.gz (101 Mbyte, uncompresses to 269 Mbyte)
- Mapunit polygon coverage in Arc/Info EXPORT format.
-
mu_awc.e00.gz (86 kbyte, uncompresses to 301 kbyte)
- INFO table giving mean available water capacity for each mapunit, in
Arc/Info EXPORT format.
The mapunits have been gridded at 30-arcsec cell size. The available water
capacity for each grid cell may be downloaded as a single file:
Warning -- The uncompressed version of the grid
file below is very much larger than the compressed version.
-
awcgrid.e00.gz (10.4 Mbyte, uncompresses to 191 Mbyte)
- 30-arcsec grid giving available water capacity, in Arc/Info grid format.
The 30-arcsec gridded data are also available as a three-dimensional array of
8-bit unsigned binary values. The data are organized as three
two-dimensional layers, giving, respectively, total AWC for columns of
100, 150, and 250 cm. Within each layer, the values are arranged by
horizontal rows. All values for the first layer (100 cm AWC) are given
first, starting with the value for the left (western) end of the top
(northern-most) row, and continuing left to right along the row. The
data for the last row of the first layer are then followed by the top
row of the second layer, and so on.
The array contains 2984 rows of 6936 values each. Code for reading the
binary array is available in Fortran 77
and C.
The data are contained in a single file:
-
awc.bsq.gz (6.2 Mbyte, uncompresses to 62 Mbyte)
- Three-dimensional array of 8-bit unsigned integer values for available
water capacity for each grid cell.
The same array is also available in LAS format (files awc.img.gz and
awc.ddr).
The filesystems containing the datasets are cross-mounted on the local
ESSC computer network. Local Arc/Info users may find it more convenient
to copy necessary files directly to their own workspaces using the
Arc/Info COPY and COPYINFO commands. The needed directories and files
(under directory $DSREF/1996-0089/) are
- awcgrid
- Arc/Info grid giving available water capacity for each 30-arcsec grid
cell.
- ../mapunits/mu_poly
- Arc/Info coverage containing polygon version of mapunit boundaries.
- info!MU_AWC
- INFO table giving available water capacity for each mapunit.
Last change: 2006 Apr 14,
R. A. White / raw@essc.psu.edu
Methodws |
Datasets |
Image
STATSGO Mapunits |
Soil Texture Class |
Depth to Bedrock
Sand, Silt, Clay Fractions |
Rock Fragment Class |
Rock Fragment Volume
Bulk Density |
Porosity |
Permeability
Available Water Capacity |
pH |
Plasticity
K-Factor |
Hydrologic Soil Groups |
Curve Numbers
Background |
Methods |
Data Coverages |
Citation |
Feedback
CONUS-Soil |
STATSGO |
SSURGO
|