SMEX03 Landsat Thematic Mapper Imagery: Oklahoma

Summary

This data set provides imagery developed from Landsat 5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper (ETM+) data for use in studying land cover features during the Soil Moisture Experiment 2003 (SMEX03). Three false color images are provided for the regional study areas north and south of Oklahoma City, Oklahoma, USA for 13 April, 29 April, and 10 July 2003. The images are the result of combining bands 2, 3, and 4 as blue, green, and red to generate false color composites. Data are provided in GeoTIFF formatted files and are available via FTP.

These data were collected as part of a validation study for the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E). AMSR-E is a mission instrument launched aboard NASA's Aqua Satellite on 04 May 2002. AMSR-E validation studies linked to SMEX are designed to evaluate the accuracy of AMSR-E soil moisture data. Specific validation objectives include assessing and refining soil moisture algorithm performance; verifying soil moisture estimation accuracy; investigating the effects of vegetation, surface temperature, topography, and soil texture on soil moisture accuracy; and determining the regions that are useful for AMSR-E soil moisture measurements.

Citing These Data

The following example shows how to cite the use of this data set in a publication. For more information, see our Use and Copyright Web page.

Jackson, Thomas J. and Michael H. Cosh. 2007. SMEX03 Landsat Thematic Mapper Imagery: Oklahoma. Boulder, Colorado USA: National Snow and Ice Data Center. Digital media.

Overview Table

Category	Description
Data format	GeoTIFF imagery (.tif) and TIFF world files (.tfw)
Spatial coverage and resolution	Southernmost Latitude: 34.42° N Northernmost Latitude: 36.88° N Westernmost Longitude: 98.34° W Easternmost Longitude: 97.42° W
Temporal coverage and resolution	13 April, 29 April, and 10 July 2003
Tools for accessing data	A program which recognizes the GeoTIFF file format is recommended for these images.
File naming convention	TM#_MMDDYY.tif and TM#_MMDDYY.tfw
File size	1 KB to 284 MB
Parameter(s)	Infrared Imagery Visible Imagery
Procedures for obtaining data	Data are available via FTP.

Table of Contents

1. Contacts and Acknowledgments
2. Detailed Data Description
3. Data Access and Tools
4. Data Acquisition and Processing
5. References and Related Publications
6. Document Information

1. Contacts and Acknowledgments

Investigator(s)

Thomas J. Jackson
USDA ARS Hydrology and Remote Sensing Lab
Beltsville, MD 20705
USA

Michael H. Cosh
USDA ARS Hydrology and Remote Sensing Lab
Beltsville, MD 20705
USA

Technical Contact

Acknowledgements

The investigators would like to acknowledge the following people: The many graduate students and volunteers who worked to collect the field data. The Soil Moisture Experiment 2003 Science Team and the Grazinglands Research Laboratory (USDA-ARS) for their assistance. The National Aeronautics and Space Administration for their generous contributions to the study. This work was supported by the NASA Aqua AMSR, Terrestrial Hydrology and Global Water Cycle Programs.

2. Detailed Data Description

For this study, TM and ETM+ bands 2, 3, and 4 were combined to make false color composites.

• Vegetation appear as shades of red. Brighter reds indicate thicker vegetation.
• Soils with little or no vegetation appear as shades from white (sands) to green or brown, depending on moisture and vegetation content.
• Water appears blue.
• Urban areas appear as blue-gray.
• Clouds and snow appear bright white.

Format

Data are provided as GeoTIFF image files with associated TIFF world files (TFW) containing georeferencing information. GeoTIFF defines a set of publicly available TIFF tags that describe cartographic and geodetic information associated with TIFF images. GeoTIFF enables referencing a raster image to a known geodetic model or map projection. The initial tags are followed by image data, that in turn, may be interrupted by more descriptive tags. By using the GeoTIFF format, both metadata and image data can be encoded into the same file.

TFW files provide georeference information for the image with the same file name. Each TFW file is a text file with six numbers, described below:

Table 1: TFW File Rows

Row	Description
1	the dimension of a pixel in map units in the x direction
2	rotation term for row
3	rotation term for column
4	the dimension of a pixel in map units in the y direction
5	x coordinate for upper left corner
6	y coordinate for upper left corner

File Naming Convention

Files are named according to the following convention:

Example File Names: TM5_071003.tif and TM5_071003.tfw

TM#_MMDDYY.tif and TM#_MMDDYY.tfw

Where

# = Landsat number (5 or 7)
MM = month
DD = day
YY = year

File Size

File sizes are approximately 284 MB each for the .tif files and 1 KB each for the .tfw files.

Spatial Coverage

Southernmost Latitude: 34.42° N
Northernmost Latitude: 36.88° N
Westernmost Longitude: 98.34° W
Easternmost Longitude: 97.42° W

Spatial Resolution

The Landsat TM and ETM+ data are high-resolution 30 m data.

Projection

Universal Transverse Mercator (UTM) Zone 15.

Temporal Coverage

13 April, 29 April, and 10 July 2003

Parameter or Variable

Infrared Imagery (Band 4)
Visible Imagery (Bands 2 and 3)

Parameter Description

Bands 2, 3, and 4 as blue, green, and red are used to generate false color images that can be used to identify land cover and vegetation.

Parameter Source

TM scenes from Landsat 5 and ETM+ scenes from Landsat 7 were acquired during the study period. The following table details the Landsat coverage for the dates of the study.

Table 2: Landsat Coverage Details

Date	Landsat Number	Path / Row
April 13	7	28/35 & 28/36
April 29	7	28/35 & 28/36
July 10	5	28/35 & 28/36

Sample Data Record

Figure 1: False Color Image of the Oklahoma City Area, Sample from Image File TM5_071003.tif.

3. Data Access and Tools

Data Access

Images are available via FTP.

Volume

Total volume is approximately 850 MB.

Software and Tools

A program which recognizes the GeoTIFF file format is recommended for these images.

Related Data Collections

• AMSR-E Validation Data: Soil Moisture Data: Data sets from SMEX campaigns available at NSIDC.
• AMSR-E/Aqua Data at NSIDC: AMSR-E standard products available at NSIDC.

4. Data Acquisition and Processing

Sensor or Instrument Description

TM is a multispectral scanning radiometer carried on Landsats 4 and 5. The TM has seven spectral bands, with a spatial resolution of 30 m for most bands.

ETM+, an improved version of TM, is carried on Landsat 7. The ETM+ has eight spectral bands with a spatial resolution of 30 m for most bands.

5. References and Related Publications

U.S. Geological Survey (USGS). Landsat Missions. 1 May 2008. http://landsat.usgs.gov/ 1 May 2008.

Sheffner, Ed. Landsat Program. 5 October 1991. http://geo.arc.nasa.gov/sge/landsat/landsat.html 31 October 2007.

Please see the USDA SMEX03 Web site for in depth information on the science mission and goal of the SMEX project.

6. Document Information

Acronyms and Abbreviations

The following acronyms and abbreviations are used in this document.

Table 3: Acronyms and Abbreviations

AMSR-E	Advanced Microwave Scanning Radiometer - Earth Observing System
ARS	Agricultural Research Service
ETM+	Enhanced Thematic Mapper
FTP	File Transfer Protocol
GeoTIFF	Georeferenced Tag(ged) Image File Format
NASA	National Aeronautics and Space Administration
NSIDC	National Snow and Ice Data Center
SMEX	Soil Moisture Experiment
TFW	TIFF World File
TIFF	Tag(ged) Image File Format
TM	Thematic Mapper
URL	Uniform Resource Locator
USDA	United States Department of Agriculture
UTM	Universal Transverse Mercator

Document Creation Date

31 October 2007

Document Revision Date

1 May 2008 - Updated new USGS Landsat web page.

Document URL

http://nsidc.org/data/docs/daac/nsidc0322_smex03_tm_geotiff_ok.gd.html