Module 5 - Exploration and Discovery

A) About the Data Files on the CD-ROM

Objectives

Students will learn the origin and type of the data files on the SIR-CED CD-ROM.
Students will know which software package to use to open each data file.

The directory /DATA contains all of the image files and data files to be used in the SIR-CED program. The image files can be opened by using the Sigma0 or Netscape, depending on the type of image. The /DATA directory contains two sub-directories:

/DATA/LOCATION - Images classified by continents and oceans
/DATA/MODS1TO5 - Images for the lesson modules 1 to 5

The directory Mods1to5 contains all the image data files to be used in introducing Modules 1 to 5 of the SIR-CED package. It is recommended that you copy over the data files from Mods1to5 for each module to your own computer before setting up to teach a lesson using these files. You may also want to copy the software you are going to use into this directory (e.g.Sigma0).

A Hint for the Classroom

Data contained in directories Pre-SIRC for each site should be regarded as a look at the sites to be covered by SIR-C. It was generated prior to SIR-C launch, and therefore does not contain any SIR-C data. Data contained in directories labeled Post-SIRC for each site contain radar images, hand-held photographs and other information obtained during the SIR-C mission and put together afterwards.

For each site, varying degrees of data were found to be available. Some sites have radar data from the NASA/JPL AIRSAR (in the Pre-SIRC directories); others have radar images and shuttle hand-held photographs from the SIR-C missions (in the Post-SIRC directories); some have scanned radar images from earlier imaging radar missions such as SEASAT or SIR-B; some have photos taken on the ground; some have digital topographic maps; some have optical or infra-red images; most have a text file describing the aims of the SIR-C investigators for the site or text files describing some of the SIR-C results obtained for that site.

In producing the files contained in this CD, we have tried to ensure that the user can open the files without knowing the file dimensions, as much as possible. Thus many image data files are in GIF format, which are fairly standard (compressed) data formats which many programs can access. We have also tried to keep file sizes down as much as possible to below 1.4Mbytes, so that files can easily be copied onto a high density floppy disk for circulation. The major exceptions to this are most of the movie clips, which tend to be bigger than 1.4 Mbytes, and some of the color images generated during the SIR-C missions.

The directory Software contains software for the PC which can be used to display and interact with the image data on the CD-ROM and open text files. There are three programs in the Software directory which you may wish to install your own computer:

Netscape - Browser program. Used to read all *.htm files.
Quicktime Movie Player - A program which plays video clips using Quicktime. Use to open files with names ending in .mov
Sigma0 - A program for display and interaction with radar images. Used to open files with names ending in .stk

You cannot run these programs directly off the CD-ROM. You must install them on your computer first. In each program directory, there is a README.TXT file that contains installation instructions.

With the three programs listed above you should be able to open most of the files contained on the CD-ROM.

To open a file ending with .stk you should use Sigma0. Simply double click on the Sigma0 icon and under the file menu drag down and select Open Compressed Stokes. Find your way to directories that contain files that end with .stk. Select that file and it will automatically open. For further information, there is an introduction in How Do I Use Sigma0?

File Types

1) PreSIR-C Text Files

These files are all PreSIR-C files in that they were generated before the SIR-C missions. Most of these files originated from a Macintosh computer and have not been translated for the PC (yet).

DirIndex.txt - text file containing an index of the files contained in the site directory. Data are in a Macintosh Teachtext format file. File can be opened using Macintosh Teachtext software by double-clicking on the file icon or opening using the Open option under the FILE menu in Teachtext. The Teachtext software application can be found in the Software directory on the SIR-CED CD-ROM. Teachtext files can also be opened by many other types of word processing programs, such as Microsoft Word, WordPerfect and MacWrite Pro. All of these programs are distributed by commercial vendors and can not be found on the SIR-CED CD-ROM.

SiteWord.txt - text file describing the site in the carefully chosen words of the SIR-C investigators. Contains a technical description of the main thrusts of the investigations being carried out at the site, a list of the SIR-C investigators involved, a description of any planned field work by the investigator team, a list of requirements for SIR-C and Shuttle photo coverage, and anticipated results from the SIR-C experiments conducted at the site. Data are in a Microsoft Word (v5.1) format file. File can be opened using Microsoft Word (v5.1) software by using the Open option under the FILE menu in Microsoft Word (v5.1).

SiteText.txt - text file describing the site in the carefully chosen words of the SIR-C investigators. Contains a technical description of the main thrusts of the investigations being carried out at the site, a list of the SIR-C investigators involved, a description of any planned field work by the investigator team, a list of requirements for SIR-C and Shuttle photo coverage, and anticipated results from the SIR-C experiments conducted at the site. Data are in a Teachtext format file which is a duplicate of the Microsoft Word (v5.1) file SiteWord.txt. File can be opened using Teachtext software by double-clicking on the file icon or opening using the Open option under the FILE menu in Teachtext.

2) PreSIR-C AIRSAR Data Files

CBandRed.STK - NASA/JPL AIRSAR data, corresponding to C-band wavelength (6cm), in Stokes matrix compressed format. From the Stokes matrix format, images representing radar backscatter for different polarizations can easily be generated. Data was generated by NASA's airborne imaging radar system, known as AIRSAR, which produces Stokes matrix data for three frequencies at the same time. Data have been reduced from original size by averaging over a box of four by four (4x4) pixels to produce one output pixel. File can be opened using the Open Compressed Stokes option under the FILE menu of the Sigma0 software.

LBandRed.STK - NASA/JPL AIRSAR data, corresponding to L-band wavelength (24cm), in Stokes matrix compressed format. From the Stokes matrix format, images representing radar backscatter for different polarizations can easily be generated. Data was generated by NASA's airborne imaging radar system, known as AIRSAR, which produces Stokes matrix data for three frequencies at the same time. Data have been reduced from original size by averaging over a box of four by four (4x4) pixels to produce one output pixel. File can be opened using the Open Compressed Stokes option under the FILE menu of the Sigma0 software.

PBandRed.STK - NASA/JPL AIRSAR data, corresponding to P-band wavelength (68cm), in Stokes matrix compressed format. From the Stokes matrix format, images representing radar backscatter for different polarizations can easily be generated. Data was generated by NASA's airborne imaging radar system, known as AIRSAR, which produces Stokes matrix data for three frequencies at the same time. Data have been reduced from original size by averaging over a box of four by four (4x4) pixels to produce one output pixel. File can be opened using the Open Compressed Stokes option under the FILE menu of the Sigma0 software.

LBandFul.gif - NASA/JPL AIRSAR data, corresponding to L-band wavelength (24cm), with HH polarization. Data was generated by NASA's airborne imaging radar system, known as AIRSAR, which produces Stokes matrix data for three frequencies at the same time. Data are a GIF format file corresponding to a full-size L-band HH image generated from the original AIRSAR data.

3) SIR-C data Files (in PostSIRC directories)

CMnnnnnC.STK - SIR-C data, corresponding to C-band wavelength (6cm), in Stokes matrix compressed format. From the Stokes matrix format, images representing radar backscatter for different polarizations can easily be generated. Data was generated by NASA's Spaceborne Imaging Radar-C, known as SIR-C, which produces Stokes matrix data for two frequencies at the same time. Data have been reduced from original size by averaging. File can be opened using the Open Compressed Stokes option under the FILE menu of the Sigma0 software.

CMnnnnnL.gif - SIR-C data, corresponding to C-band wavelength (6cm), total power, which is all polarizations added together. Data was generated by NASA's Spaceborne Imaging Radar-C, known as SIR-C, which produces Stokes matrix data for two frequencies at the same time. Data are a GIF format file corresponding to a C-band image generated from the original SIR-C data (in the .stk file).

CMnnnnnL.STK - SIR-C data, corresponding to L-band wavelength (24cm), in Stokes matrix compressed format. From the Stokes matrix format, images representing radar backscatter for different polarizations can easily be generated. Data was generated by NASA's Spaceborne Imaging Radar-C, known as SIR-C, which produces Stokes matrix data for two frequencies at the same time. Data have been reduced from original size by averaging. File can be opened using the Open Compressed Stokes option under the FILE menu of the Sigma0 software.

CMnnnnnL.gif - SIR-C data, corresponding to L-band wavelength (24cm), total power, which is all polarizations added together. Data was generated by NASA's Spaceborne Imaging Radar-C, known as SIR-C, which produces Stokes matrix data for two frequencies at the same time. Data are a GIF format file corresponding to an L-band image generated from the original SIR-C data (in the .stk file).

4) Other Image Files

Shuttlen.gif - digitized hand-held photograph, taken by the NASA Space Shuttle crew. Data are a GIF format file.

SEASATim.gif - SEASAT (L-band HH) radar image of the area from the SEASAT mission in 1978. Data have been scanned from a photo product and are not calibrated. Data are in a GIF format file.

SIRAimgn.gif - SIR-A (L-band HH) radar image of the area from the SIR-A mission in 1981. Data have been scanned from a photo product and are not calibrated. Data are in a GIF format file.

SIRBimgn.gif - SIR-B (L-band HH) radar image of the area from the SIR-B mission in 1984. Data have been scanned from a photo product and are not calibrated. Data are in a GIF format file.

JERS1imn.gif - JERS-1 (L-band HH) radar image of the area from the Japanese JERS-1 imaging radar mission. Image was generated in 1992. Data have been scanned from a photo product and are not calibrated. Data are in a GIF format file.

ESARimag.gif - X-band radar image of the area from the German E-SAR airborne SAR system, operated by the German Aerospace Research Institute (DLR). Data have been scanned from a photo product and are not calibrated. Data are in a GIF format file.

AerialPn.gif - aerial photograph taken from a plane. Data have been scanned from a photo product. Data are in a GIF format file.

GroundVn.gif - digitized photograph taken from the ground by a SIR-C investigator or a member of the SIR-C team. Data are in a GIF format file.

LocatMpn.gif - digitized map of the area, taken by from a USGS map of the site, or from a map provided by the SIR-C investigator. Data are in a GIF format file.

Landsatn.gif - Landsat image of the area. Data may be optical, infra-red or a combination of bands. Data are in a GIF format file.

Topomapn.gif - digitized topographic map of the area, taken from a NASA/JPL TOPSAR image data set or a USGS topographic map of the site. Data are in a GIF format file. When opened the 'pixel value' should correspond to the height above sea level in meters.

Other.gif - many of the images generated during the SIR-C mission have been named according to what they represent. They usually have a text file (named Other.txt) which explains what the GIFure shows.

5) Vegetation Map files (in Pre-SIR-C directories)

Vegmpbyt.gif - vegetation map of the area, generated from NASA/JPL AIRSAR data, using an algorithm developed by A. Freeman of JPL. Each pixel is classified as corresponding to an urban area (e.g. a city or town); a forest; medium vegetation, such as shrubs or a mature corn field; low vegetation, such as grassland, scrub or low-lying agricultural crops (e.g. wheat or barley); no vegetation (rocks, bare soil and water surfaces). Within the three vegetated classes (forest, medium and low vegetation) there is a further subdivision into, for example, forest which has a significant amount of double-bounce [Forest (D)] and forest which doesn't [Forest]. The classification is based on a model of the scattering mechanisms expected from these different ground cover types at all three AIRSAR frequencies and was trained on AIRSAR data from a few different types of scene. Some pixels are unclassified and are designated as bright, medium or dark. These pixels do not match the models. Data are in a GIF format file.

WARNING - the vegetation maps in the Vegmpbyt.gif files are our best estimate of the ground cover class based on current models and understanding of radar backscatter. They may be wrong in some cases.

Vegmpkey.gif - color-coded key to the Vegmpbyt.gif files. Displayed at the same time as the Vegmpbyt.gif image data file, it allows the vegetation map to be visually interpreted. Data are in a GIF format file.

VegmpHdr.txt - header file for the Vegmpbyt.gif files. Lists the source file, the classes used in the classifier, the byte value (between 1 and 12) assigned to each, and the percentage occurrence of each class when the classifier was ran. Data are in a Macintosh Teachtext format file.

Teacher's Guide - Table of Contents

Converted to the IBM-PC by Al Wong, sirced03@southport.jpl.nasa.gov

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