Data Set ID:

SMEX03 Land Use Classification Data: Georgia, Version 1

This data set is a subset of data acquired from the United States Geological Survey's (USGS) National Land Cover Dataset (NLCD). The NLCD is comprised of Landsat data collected during 2001 that are representative of the land cover conditions present in the Georgia, USA regional study area during the Soil Moisture Experiment of 2003 (SMEX03).

This is the most recent version of these data.

Data Format(s):
  • ASCII Text
Spatial Coverage:
N: 31.90326, 
S: 30.96107, 
E: -83.36425, 
W: -83.97085
Spatial Resolution:Not SpecifiedSensor(s):TM
Temporal Coverage:
  • 1 June 2003 to 31 July 2003
Temporal ResolutionNot specifiedMetadata XML:View Metadata Record
Data Contributor(s):Michael Cosh

Geographic Coverage

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As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.

Cosh, M. and J. Birch. 2009. SMEX03 Land Use Classification Data: Georgia, Version 1. [Indicate subset used]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. doi: [Date Accessed].

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Detailed Data Description


Data are provided in one ArcInfo ASCII Grid data file named ga_land_cover.txt. The first six rows of the file contain header information, while the remaining rows contain the actual grid data. Refer to Table 1 for clarification of ASCII Grid header variables, or to the Sample Record section of this document to view the sample data record. Missing data are represented by -9999. The Georgia study area image dimensions are 3440 rows by 1840 columns.

Table 1. ArcInfo ASCII Grid Header Values
Variable Description
ncols Number of columns in the grid
nrows Number of rows in the grid
xllcorner Western edge of the grid
yllcorner Southern edge of the grid
cellsize Spatial resolution of the grid
NODATA_value Refers to value representing missing data, such as -9999

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File and Directory Structure

Both the ga_land_cover.txt data file and readme.txt file are available on the HTTPS site in the following directory:

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File Naming Convention

The abbreviation ga in the ASCII file name ga_land_cover.txt indicates Georgia as the regional study area.

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The data file is approximately 19 MB.

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Spatial Coverage

Southernmost Latitude: 30.96106485° N
Northernmost Latitude: 31.90325745° N
Westernmost Longitude: 83.97084687° W
Easternmost Longitude: 83.36425277° W

Spatial Resolution

The pixel size is 30 m by 30 m.

Projection and Grid Description

Universal Transverse Mercator (UTM), Zone 17, North American Datum 1983 (NAD 83)

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Temporal Coverage

The NLCD 2001 land use classification data are representative of typical conditions in Georgia during the approximate timeline of the SMEX03 campaign, conducted between June and July 2003.

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Parameter or Variable

The measured parameter for this data set is land use classification.

Parameter Range

The parameter range for Georgia land cover types is described in Table 2. Valid values range from 1 to 99, with not all values present in the Georgia study area. For more complete descriptions of land cover types, and for more information on land cover types not present in the Georgia study area, please refer to the USGS Web GIS Web site.

Table 2. Land Cover Parameter Range and Description
Parameter Values Description
11 Open Water
21 Developed, Open Space
22 Developed, Low Intensity
23 Developed, Medium Intensity
24 Developed, High Intensity
31 Barren Land (Rock/Sand/Clay)
41 Deciduous Forest
42 Evergreen Forest
43 Mixed Forest
52 Shrub/Scrub
71 Grassland/Herbaceous
81 Pasture/Hay
82 Cultivated Crops
90 Woody Wetlands
95 Emergent Herbaceous Wetlands

Sample Data Record

Figure 1 displays a sample of the data file ga_land_cover.txt containing Georgia land use classification data. The first six rows display ArcInfo ASCII Grid header information, while the last six rows of this partial data record contain land use classification measurements. Only the first thirteen columns and first twelve rows of the data record are shown in this sample. For clarification of ASCII Grid header variables, refer to Table 1 in the Format section.

Figure 1. Sample Data Record
ncols 1840
nrows 3440
xllcorner 219000
yllcorner 3429000
cellsize 30
NODATA_value -9999
42 42 42 41 41 41  90  42  42  42  42  42  90  ...
43 42 42 41 90 41 90 42 42 42 42 42 82 ...
41 43 43 90 90 90 90 42 42 42 41 42 42 ...
41 43 90 90 90 41 41 42 42 41 41 42 82 ...
43 90 90 90 90 41 42 42 43 41 41 42 42 ...
41 43 41 41 90 41 43 41 41 41 43 43 43 ...
... ... ... ... ... ... ... ... ... ... ... ... ... ...
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Software and Tools

Any text editor or Web browser is recommended to view these data.

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Data Acquisition and Processing

Data Acquisition Methods

The Georgia land use classification data were retrieved from an online USGS database called WebGIS, a Landsat-based land cover database with several independent data layers. From this database, the National Land Cover Dataset (NLCD) for 2001 was selected. The NLCD 2001 data were then exported with ArcMap as ArcInfo ASCII Grid data files. No extensive ground-based land cover retrieval was conducted as part of SMEX03. Instead, the NLCD 2001 is considered the base land cover map since land cover over the SMEX03 study regions is minimally dynamic.

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References and Related Publications

Contacts and Acknowledgments

Michael H. Cosh
Hydrology/Remote Sensing Laboratory
US Department of Agriculture (USDA) - Agricultural Research Service (ARS)
Bldg. 007, Rm. 104, BARC-West
Beltsville, MD 20705 USA

Joanna Birch
Hydrology/Remote Sensing Laboratory
US Department of Agriculture (USDA) - Agricultural Research Service (ARS)
Bldg. 007, Rm. 104, BARC-West
Beltsville, MD 20705 USA

Document Information



No technical references available for this data set.

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