Sevilleta National Wildlife Refuge, near Albuquerque, New Mexico

\log

12/20/97 - Date this file created. G. Shore.
10/30/01 - Added date/time fields to APPENDIX II section. G. Shore.


\doc

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DATA SET CODE AND TITLE

SEV031 AVHRR Biweekly Composites (1994)


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ABSTRACT
This dataset contains 16 separate 14-day composited AVHRR
images for 1994 clipped approximatedly to the New Mexico State
boundaries (plus 50 Km buffer around boundary). These were
obtained from the U.S. Geological Survey's EROS Data Center (EDC),
National Mapping Division, from the "CONTERMINOUS U.S. AVHRR BIWEEKLY
COMPOSITES" CD product series.


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KEYWORDS
SEV031 AVHRR Advanced_Very_High_Resolution_Radiometer NOAA Satellite_Imagery Remote_Sensing USGS_EROS_Data_Center 1994


##############################################################
TABLE OF CONTENTS
I. WHY THE DATA WERE COLLECTED
II. WHEN THE DATA WERE COLLECTED
III. WHO IS INVOLVED WITH THE DATA
IV. WHERE TH DATA WERE COLLECTED
V. HOW THE DATA WERE COLLECTED AND PROCESSED BY THE USGS EDC
VI. HOW THE DATA WERE PROCESSED BY THE SEVILLETA IMS (SIMS)
VII. APPENDIX I - USGS EDC Metadata
VIII. APPENDIX II - Pixel Date Attribute Table


##############################################################
I. WHY THE DATA WERE COLLECTED

See the U.S. Geological Survey's EROS Data Center (EDC)
documentation in APPENDIX I below.


##############################################################
II. WHEN THE DATA WERE COLLECTED

Sixteen 14-day composites for 1994. See the U.S. Geological
Survey's EROS Data Center (EDC) documentation in APPENDIX I below
for specific composite periods.


##############################################################
III. WHO IS INVOLVED WITH THE DATA

SOURCE AGENCY CONTACTS:
See the U.S. Geological Survey's EROS Data Center (EDC) documentation
in APPENDIX I below for USGS EDC contacts.

LOCAL SEVILLETA LTER CONTACTS:
Primary contact:
Greg Shore, Sevilleta LTER (gshore@sevilleta.unm.edu).

Principle investigators:
Bruce Milne, Sevilleta LTER (bmilne@sevilleta.unm.edu)

GIS/GPS specialist:
Greg Shore, Sevilleta LTER (gshore@sevilleta.unm.edu).

Data Management
Greg Shore, Sevilleta LTER (gshore@sevilleta.unm.edu)


##############################################################
IV. WHERE THE DATA WERE COLLECTED

The original biweekly composited images covered the
Conterminous United States. However, the images were clipped
to the approximate New Mexico State boundaries (plus 50 Km buffer
around boundary) for online access purposes, while the full U.S.
scenes are stored offline on tape. The clipping coordinates were
selected to perform exact clipping, so no resampling was required.
The approximate online (NM clipped) boundaries are:

Latitude/Longitude, decimal degrees (Clarke 1866 spheroid)
XMIN: -109.515170 YMIN 30.759247 XMAX -102.454601 YMAX 37.817184

Lambert Azimuthal Equal-area (see EDC document for projection info)
XMIN: -914000 YMIN -1529000 XMAX -216000 YMAX -795000

The source and the clipped images are in the following map projection:
Lambert Azimuthal Equal Area projection
Parameters:
Radius of sphere 6,370,997.0 meters
Longitude of central meridian 100 00 00 West
Latitude of origin 45 00 00 North
False easting 0
False northing 0
Units of measure meters
Pixel size 1,000 meters

Each clipped image has 735 rows and 699 columns, and has a cell size
of 1000 x 1000 m.

See the U.S. Geological Survey's EROS Data Center (EDC) documentation
in APPENDIX I below for spatial extent, projection information, etc.,
related to the full Conterminous US scenes.


##############################################################
V. HOW THE DATA WERE COLLECTED AND PROCESSED BY THE USGS EDC

See the U.S. Geological Survey's EROS Data Center (EDC)
documentation in APPENDIX I below.


##############################################################
VI. HOW THE DATA WERE PROCESSED BY THE SEVILLETA IMS (SIMS)

The general SIMS processing steps for each biweekly composite
period were to read the 10 image bands off the source USGS-EDC CD,
concatenate/import them into a 10-band ERDAS Imagine format image
file, georegister to the USGS-EDC specifications, clip the scene
to the approximate New Mexico State boundaries, move the clipped
scene to the online SIMS archive, and write the full scene to
offline tape.

The band order in the archived scenes is:

1- NOAA CHANNEL 1 6- NDVI
2- NOAA CHANNEL 2 7- SATELLITE ZENITH
3- NOAA CHANNEL 3 8- SOLAR ZENITH
4- NOAA CHANNEL 4 9- RELATIVE AZIMUTH
5- NOAA CHANNEL 5 10- DATE

The bands are described in detail in the U.S. Geological Survey's
EROS Data Center (EDC) documentation in APPENDIX I below. The
attribute data for the "DATE" band is found in APPENDIX II below.

A more precise description of the processing steps is as follows:

1. Mount AVHRR CD

2. Read the 10 bands of information off the CD for each biweekly composited
scene, concatenate the 10 bands into a single file, then import as an
ERDAS Imagine 10-band image file (of size 2889 rows x 4587 cols). This
process was automated with the C-shell script:

/db/local/imagery/bincom/avhrr_import.csh 94

NOTE: this generates 10-band ERDAS Imagine format files, that are of
image size 2889 rows x 4587 cols, with filenames as follows:

avhrr94pPP.img

where: PP = bi-weekly growth period number

and bands in following order::
1- NOAA CHANNEL 1 6- NDVI
2- NOAA CHANNEL 2 7- SATELLITE ZENITH
3- NOAA CHANNEL 3 8- SOLAR ZENITH
4- NOAA CHANNEL 4 9- RELATIVE AZIMUTH
5- NOAA CHANNEL 5 10- DATE

3. Georegister the scene as follows:
Bring up ERDAS Imagine GUI, then Tools->ImageInfo tool and do:
1. File->Open->avhrr94pPP.img
2. Edit->Change Map Model:
a. Upper Left X: -2050000
b. Upper Left Y: 752000
c. Pixel Size X: 1000
d. Pixel Size Y: 1000
e. Units: meters
f. Projection: Lambert Azimuthal Equal-area
NOTE: click OK, then answer "Yes" to changing Map Model in all layers.
3. Edit->Add/Change Projection:
a. Spheroid Name: Sphere of Radius 6370997m
b. Datum Name: Undefined
c. Longitude of center of projection: 100:00:00 W
d. Latitude of center of projection: 45:00:00 N
e. False easting: 0.0 meters
f. False northing: 0.0 meters
NOTE: click OK, then answer "Yes" to changing Map Model in all layers.
4. Edit->Change Layer Name:
a. Change bands 1 - 5 to Channel_1, Channel_2, ..., Channel_5,respectively
b. Change band 6 to NDVI
c. Change bands 7 - 10 to SATELLITE_ZENITH, SOLAR ZENITH,
RELATIVE_AZIMUTH, and DATE, respectively

4. Clip full-scene to New Mexico minimum bounding box (+50 Km buffer) with
coordinates ULx = -914000, ULy = -795000, LRx = -216000, LRy = -1529000,
and dimensions 735 rows x 699 columns. This process was automated with
the C-shell scripts:

/db/local/imagery/bincom/batch_avhrr_clip2nm.csh, which calls:
/db/local/imagery/bincom/avhrr_clip2nm.csh avhrr94pPP.img avhrr94pPPnm.img

NOTE: this generates 10-band ERDAS Imagine format files, that are of
image size 735 rows x 699 cols, with filenames as follows:

avhrr94pPPnm.img

5. Unix compress the NM clipped image, make an archive directory, and move it
to the archive destination (/db/archive/imagery/avhrr/avhrr94pPP/). This
process was automated with the C-shell scripts:

/db/local/imagery/bincom/avhrr_archive.csh

NOTE: this generates Unix compressed files with filenames as follows:

avhrr94pPPnm.img.Z

6. Compress (gzip) and archive the full scene image to 4mm DAT tape, then
remove from online disk:

gzip avhrr94pPP.img
mt -f /dev/rmt/0cn fsf <#>
tar cvf /dev/rmt/0cn avhrr94pPP.img.gz
rm avhrr94pPP.img.gz

7. Copy the most current yearly "USGS-EDC-AVHRR Dataset README" file off CD for
inclusion in the online SIMS IAF metadata file (avhrr94.dbf) for the images
(note, must also convert from DOS to Unix file):

dos2unix /cdrom/cdrom0/readme.1st avhrr94readme.1st

8. Copy the "Date of Acquisition by Pixel" attribute file off each CD, then
split by biweekly period for inclusion in GIS/RS Metadata Abstract file
(avhrr94pPPnm.mda), and merge by year for inclusion in SIMS IAF metadata
file (avhrr94.dbf):

dos2unix /cdrom/cdrom0/geom/date.att avhrr94pPP-PPdate.att

/db/local/imagery/bincom/batch_avhrr_split_dateatt.csh, which calls:
/db/local/imagery/bincom/avhrr_split_dateatt.csh

/db/local/imagery/bincom/avhrr_concat_dates.csh 94 > avhrr94date.att

9. Generate (this) SIMS IAF metadata file (i.e., avhrr94.dbf) using template
file (avhrr_dbf.tmpl), appending readme file (avhrr94readme.1st), and date
file (avhrr94date.att).

10. Generate GIS/RS Metadata Abstract file for each image, and put with
image in appropriate directory (/db/archive/imagery/avhrr/avhrr94pPP/):

/db/local/imagery/bincom/get_avhrr_dates.csh 94 avhrr94.dbf 97 \
> avhrr94periods.txt

/db/local/imagery/bincom/batch_make_avhrr_abstract.csh avhrr94periods.txt
which calls:
/db/local/imagery/bincom/make_avhrr_abstract.csh


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VII. APPENDIX I - USGS EDC Metadata

THE 1994 CONTERMINOUS U.S. AVHRR BIWEEKLY COMPOSITES
TABLE OF CONTENTS
Page
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Data Set Characteristics . . . . . . . . . . . . . . . . . . . . . . . . .2
Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Scene Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Satellite and Solar Viewing Geometry. . . . . . . . . . . . . . . . . .6
Radiometric Calibration . . . . . . . . . . . . . . . . . . . . . . . .7
Normalized Difference Vegetation Index. . . . . . . . . . . . . . . . .9
Date of Acquisition . . . . . . . . . . . . . . . . . . . . . . . . . 10
Geometric Registration. . . . . . . . . . . . . . . . . . . . . . . . 10
Compositing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Miscellaneous Data. . . . . . . . . . . . . . . . . . . . . . . . . . 15
CD-ROM Organization. . . . . . . . . . . . . . . . . . . . . . . . . . . 20
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26


THE 1994 CONTERMINOUS U.S. AVHRR BIWEEKLY COMPOSITES
PREFACE
The conterminous U.S. Advanced Very High Resolution Radiometer (AVHRR)
biweekly composites data set provided in the past have been developed as
annual data sets, with a single biweekly composite for January and February, a
continuous series of biweekly composites for the months from March through
October, and biweekly composites for the months of November and December. The
biweekly composites are produced from afternoon acquisitions of NOAA-11 data.
Unfortunately, on September 13, 1994 the operational AVHRR sensor on board
NOAA-11 failed. Consequently, the 1994 conterminous U.S. AVHRR biweekly data
set will be for the period of January through September 15, 1994.


INTRODUCTION
In 1987, the U.S. Geological Survey's EROS Data Center (EDC), in Sioux Falls,
South Dakota, began receiving Advanced Very High Resolution Radiometer (AVHRR)
data from NOAA polar-orbiting satellites. The central location of the EDC in
the United States enables direct reception of all AVHRR overpasses of the
lower 48 States, as well as much of Canada and Mexico. Early in the 1990
growing season the EDC started acquiring NOAA-11 AVHRR 1-km resolution daily
observations to produce weekly and biweekly maximum normalized difference
vegetation index (NDVI) composites of the conterminous United States
(Eidenshink, 1992). The objective of the vegetation mapping program is to
compile, annually, a comprehensive series of calibrated, georegistered, daily
observations, and biweekly maximum NDVI composites. These data are being
published on CD-ROM for distribution of the data set. These data sets can be
used in environmental monitoring and global climate change studies.

The vegetation diversity of the conterminous United States provides
opportunities for using both AVHRR data and the NDVI for monitoring vegetation
condition in several different ecosystems, including forests, agricultural
crops, and grasslands. The data set provides a comprehensive growing season
profile of these ecosystems, is extremely useful for assessing seasonal
variations in vegetation conditions, and provides a foundation for studying
long-term changes resulting from human or natural factors.

DATA SET CHARACTERISTICS
The data set is composed of sixteen 14-day maximum NDVI composites, created
from nearly 300 NOAA-11 images. The sixteen core composite periods represent
a continuous period from March 4, 1994, to September 15, 1994. The first two
(periods 1 and 2) composites represent a 2-week period each for January and
February. The 1994 data set is available as a set of four CD-ROM's. Each of
the four discs has four biweekly composites, miscellaneous data, and that are
described later in this file. Each disc also contains the NDVI statistics of
all counties in the conterminous United States for each composite period.

Each daily observation includes nine bands of information: AVHRR channels 1-5,
NDVI, satellite zenith, solar zenith, and relative azimuth. The daily
observations have been calibrated to reflectance, scaled to byte data, and
geometrically registered to the Lambert Azimuthal Equal Area map projection.

Each 14-day composite includes 10 bands of information, the 9 bands described
above for each daily observation and a 10th band, which is a pointer to
identify the date of the source daily observation scene. The data for each
pixel in the composite are extracted from the daily observation scene on the
basis of the maximum NDVI compositing process.

The 14-day composite periods for 1994 were:
____________________________________________________
Period Date of coverage Julian day
____________________________________________________

1 01/07 - 01/20/1994 007 - 020
2 02/11 - 02/24/1994 042 - 055
3 03/04 - 03/17/1994 063 - 076
4 03/18 - 03/31/1994 077 - 090
5 04/01 - 04/14/1994 091 - 104
6 04/15 - 04/28/1994 105 - 118
7 04/29 - 05/12/1994 119 - 132
8 05/13 - 05/26/1994 133 - 146
9 05/27 - 06/09/1994 147 - 160
10 06/10 - 06/23/1994 161 - 174
11 06/24 - 07/07/1994 175 - 188
12 07/08 - 07/21/1994 189 - 202
13 07/22 - 08/04/1994 203 - 216
14 08/05 - 08/18/1994 217 - 230
15 08/19 - 09/01/1994 231 - 244
16 09/02 - 09/15/1994 245 - 258
____________________________________________________
The image dimensions of each band are 2,889 lines and 4,587 samples (13
megabytes).

NOTE: Prior to the 1994 image compositing the format of the Land Analysis
System (LAS) files contained a 512 byte header record followed by data blocked
into 512 byte segments for each line. As a result the dimension increased to
4,608 samples. The LAS software package no longer has this criteria. Actual
image data is processed and reported as 2,889 lines by 4,587 samples.


PROCEDURES
The sections that follow describe the data processing flow that was used at
the EDC to create a composite data set. All image processing was conducted
using Land Analysis System (Ailts and others, 1990) software.

Scene Selection
Cloud-free AVHRR observations of the land surface are necessary for monitoring
the vegetation conditions. A single AVHRR overpass is seldom completely cloud
free. Holben (1986) showed that compositing AVHRR data acquired over several
days produces spatially continuous cloud-free images over large areas with
sufficient temporal resolution to study green vegetation dynamics. The
duration of consecutive daily observations is called the compositing period.
On a daily basis during a composite period, each observation of NOAA-11 data
over the conterminous United States was evaluated for cloud cover. Typically,
there are two satellite overpasses per day, one over the eastern portion of
North America and a second pass over the western part of the continent. Every
image that provided a clear observation of a large ground surface area at
reasonable nadir viewing angles is included in the composite. On an average,
18 daily observations per biweekly period are included in the composite.

Satellite and Solar Viewing Geometry
The availability of the viewing geometry information allows studies on the
effects of off-nadir viewing and the investigation of potential data
correction techniques. The solar zenith angle is used during the calibration
process to correct the solar illumination variability along an orbit.

The computation of the solar and satellite geometry is a process that derives
the satellite zenith, solar zenith, and relative azimuth angle for each image
pixel. The relative azimuth is the absolute difference between the satellite
and solar azimuth angles. The computed angles do not exceed 180 degrees. A
separate image band is created for each of these three angle computations.

The satellite zenith angle is computed in degrees, in which nadir is
represented as 90 degrees. Therefore, values less than 90 degrees represent
view angles in the backscattered (easterly) direction and values greater than
90 represent the forward scatter (westerly) direction. Note that the
effective field of view of the satellite is approximately 55 degrees each side
of nadir, but computed satellite zenith angles can exceed 55 degrees because
of the curvature of the Earth.

The relative azimuth angle is computed as the absolute difference between the
solar azimuth and the satellite azimuth angles. The computed values are in
the 0 - 180 range. The relative azimuth angle is computed instead of separate
azimuth angles because only the absolute difference between the azimuth angles
is required for atmospheric correction algorithms. Also, saving only the
computed relative azimuth angle requires only one band in a daily observation
and composite image instead of two, which reduces the image storage
requirements on CD-ROM.

Radiometric Calibration
Radiometric calibration of the AVHRR visible and near-infrared channels
(channels 1 and 2) is an important consideration because there is poor
preflight calibration, no onboard calibration, and difficulty with inflight
calibration. Preflight calibration coefficients can change while the
instrument is in storage, or after launch, because of the space environment.
Degradation of AVHRR sensors after launch has been well documented (Rao, 1987;
Price, 1987; Holben and others, 1990). Several studies have used stable sites
such as homogeneous desert targets to monitor the degradation of the sensors
after the satellite had been launched. Corrections are made for sensor
degradation by using coefficients developed from a study by Teillet and Holben
(1992) [unpublished report]. Their calculation takes into account the desert
calibration approach (Holben and others, 1990) to develop a set of
time-dependent calibration coefficients for the AVHRR sensor on NOAA-11. The
time-dependent coefficients are based on a piecewise linear fit of the desert
results. Piecewise linear fits are recommended for operational use because,
unlike polynomial fits, they will not change retroactively when new data are
added to the end of the time series.

In addition to radiometric calibration, the solar illumination variability,
which occurs in the north/south direction within an orbit, was corrected using
the cosine of the solar zenith angle. The calibration and solar illumination
correction of channels 1 and 2 was completed using the following formula:
R = (d*d/z)*kb(c-C)
where:
R is reflectance,
d is the mean earth-sun distance in astronomical units,
z is the cosine of the solar zenith angle,
k is the mean solar flux,
b is the gain coefficient,
c is the digital count, and
C is the deep space digital counts.

Reflectance values for channels 1 and 2 were converted to byte data, where the
range 0 - 254 represents 0 to 63.5 percent reflectance (0.25 percent per bin)
and the value 255 is a grouping of reflectance values greater than 63.5
percent. Any feature with greater than 63 percent reflectance is a cloud,
snow, or other bright nonvegetated surface.

The calibration coefficients for AVHRR thermal channels 3, 4, and 5 are
derived onboard the satellite using a view of a stable blackbody and deep
space as a reference (Kidwell, 1991). The calibration process converts raw
data values to energy (milliwatts/m2-steradian-cm-1) using the following
formula:

E=a+bc
where:
E is energy,
a is the intercept,
b is the gain coefficient, and
c is the digital count.

Energy is converted to brightness temperature using the inverse of Planck's
radiation function. The brightness temperatures are represented in Kelvin
units. A scaling factor was used to convert the brightness temperatures to
byte data. A scaling factor of 202.5 is subtracted from the brightness
temperature value and the difference is multiplied by 2 to maintain one half
percent accuracy (i.e., a brightness temperature of 280 becomes 155).

Normalized Difference Vegetation Index (NDVI)
The NDVI is the difference of near-infrared (channel 2) and visible
(channel 1) reflectance values normalized over the sum of channels 1 and 2
(NIR-VIS)/(NIR+VIS). The NDVI equation produces values in the range of -1.0
to 1.0, where increasing positive values indicate increasing green vegetation
and negative values indicate nonvegetated surface features such as water,
barren, ice, snow, or clouds. The NDVI can be derived at several points in
the processing flow. To retain the most precision, the NDVI is derived after
calibration of channels 1 and 2, prior to scaling to byte range. Computation
of the NDVI must precede geometric registration and resampling to maintain
precision in this calculation.

To scale the computed NDVI results to byte data range, the NDVI computed
value, which ranges from -1.0 to 1.0, is scaled to the range of 0 to 200,
where computed -1.0 equals 0, computed 0 equals 100, and computed 1.0 equals
200. As a result, NDVI values less than 100 now represent clouds, snow,
water, and other nonvegetative surfaces and values equal to or greater than
100 represent vegetative surfaces.

Date of Acquisition
The date of acquisition images are provided to allow a user to identify the
specific daily observation used for each pixel. The date images for each
composite identify each daily image as a unique value. The unique value is
linked to an inventory of the daily observations. A complete list of daily
observations used in each composite period is on this CD-ROM under the \GEOM
directory in file DATE.ATT.

Geometric Registration
The process of compositing daily observations for each biweekly period
required each daily overpass to be registered to a common map projection to
ensure that, from day to day, each 1-km pixel represented the same ground
location. The map projection chosen for the data is the Lambert Azimuthal
Equal Area. This projection is appropriate for the North American Continent
because of its visual presentation and equal area characteristic, which allows
easy measurement of area throughout the data set.

To perform the image-to-image registration of the data a base image was
developed as a reference. Tests have shown that the best way to prepare the
base image is to register individual daily orbits to an accurate base map.
The map base used is the hydrography layer of the U.S. Geological Survey
1:2,000,000-scale digital line graph (DLG). The features in the DLG data,
such as water bodies, rivers, and streams, are identifiable features in the
AVHRR 1-km data. The DLG data are rasterized to 1-km cells and registered to
the Lambert Azimuthal Equal Area projection before being used as the map base
for the data.

Approximately 20 near-nadir cloud-free segments of NOAA-11 channel 2 daily
observations from the 1989 and 1990 growing season are manually registered to
the DLG data. Each segment is verified for accuracy (root-mean-square error
less than 1 pixel). The segments are digitally mosaicked to produce a single
base image of the conterminous United States for registering the 1994 growing
season data. The accuracy of this base image is verified with a
root-mean-square error less than 1 pixel. Table 1 provides details on
projection parameters.

Table 1. Lambert Azimuthal Equal Area (LAZEA) projection
_______________________________________________________________
Parameters:
Radius of sphere 6,370,997.0 meters
Longitude of central meridian 100 00 00 West
Latitude of origin 45 00 00 North
False easting 0
False northing 0
Units of measure meters
Pixel size 1,000 meters
For the conterminous United States (1994)
Center of pixel (1,1) ( -2050000, 752000 )
Number of lines 2,889
Number of samples 4,587
LAZEA minimum bounding rectangle:
In projection meters:
Lower left ( -2050500, -2136500 )
Upper left ( -2050500, 752500 )
Upper right ( 2536500, 752500 )
Lower right ( 2536500, -2136500 )
In decimal degrees of longitude and latitude:
Lower left ( -119.9722899 23.5837576 )
Upper left ( -128.5300591 48.4030555 )
Upper right ( -65.3946489 46.7048989 )
Lower right ( -75.4163527 22.4793919 )


In degrees, minutes, and seconds of longitude and latitude:
Lower left ( -119 58 20 23 35 02 )
Upper left ( -128 31 48 48 24 11 )
Upper right ( -65 23 41 46 42 18 )
Lower right ( -75 24 59 22 28 46 )
________________________________________________________________

Each daily observation for the 1994 growing season is registered to the base
image using image-to-image correlation. To improve overall registration
accuracy, 150 samples are eliminated from each edge of the raw data image.
The 150 samples represent the most extreme off-nadir pixels and are often the
source of error in the image correlation process. Then, the channel 2 data
for each daily observation are transformed using the satellite orbit model.
Next, correlation of the original image to the reference image is performed
using a set of 255 selected ground control points. If most of the ground
control points are cloud covered in the daily observation, no correlation is
defined and the image is rejected. Otherwise, the correlation is determined
and the satellite transformation coefficients from the orbital model are
revised. Then the raw data (channels 1 - 5), NDVI, and satellite geometry
data are transformed using the revised coefficients and nearest neighbor
resampling.

Compositing
The method for determining the portion of each overpass to be included in the
composite image was to retain pixels having the highest NDVI values. The NDVI
was examined pixel by pixel for each overpass within the biweekly compositing
period to determine the maximum value.

The retention of the highest NDVI value reduces the number of
cloud-contaminated pixels because values for clouds and cloud shadows are
generally less than 100 (in the byte-scaled data) and clear day observations
of vegetated surfaces are equal to or greater than 100 (in the byte-scaled
data). The result is a near cloud-free image that depicts the maximum
vegetative greenness for the compositing period.

The product of the compositing process was a 10-band image that included the
maximum NDVI value for each pixel during the composite period, the channels
1-5 and satellite viewing geometry data from the chosen daily observations,
and a pointer value that identified the satellite overpass from which that
pixel was taken. Table 2 lists the data included in each of the 10 bands.

Table 2. Band description of composite images
__________________________________________________________________
Band Description | Band Description
__________________________________________________________________

1 AVHRR channel 1 | 6 NDVI
2 AVHRR channel 2 | 7 Satellite zenith
3 AVHRR channel 3 | 8 Solar zenith
4 AVHRR channel 4 | 9 Relative azimuth
5 AVHRR channel 5 | 10 Date
__________________________________________________________________

The date of acquisition pointer is provided to allow a user to identify the
specific AVHRR daily observation (satellite scene number) used for each pixel.
To determine the date and scene number, first identify the date pointer value
for the pixel within a composite period, then use the reference table in file
DATE.ATT to determine the scene number.

Miscellaneous Data
When displaying large areas with AVHRR data, an overlay or mask of familiar
linework, such as county boundaries, can be used as a location aid. Several
images are included in the \MISC directory to provide location information.
All of the linework images represent lines in raster format as 1-km cells.
These data sets include climatic division boundaries (CDLINES), major land
resource areas boundaries (LRALINES), county boundaries (CTYLINES), and water
bodies (WATERMSK). The climatic division lines were digitized from NOAA base
maps. The county lines are a modified version of the 1:2,000,000-scale DLG
data. The major land resource area boundaries were digitized from the U.S.
Department of Agriculture, Soil Conservation Service (1981) maps.

The linework in the CDLINES and LRALINES images is coded at the byte value
255. In the CTYLINES image, the county boundaries identified by the coasts
and international borders are at value 253, the county borders that are
coincident with State borders are at value 254, and other county boundaries
are at value 255. This variable coding provides the capability to display
coastal, State, or county boundaries from the same image. The water bodies
image has two unique identifiers. Water has a 0 value and land has a value
of 1.

Also included are three raster polygon images that can be used in an overlay
process where histograms or descriptive statistics could be computed for the
NDVI values within a polygon. These images include counties (CTYPOLY), major
land resource areas (LRAPOLY), and climatic divisions (CDPOLY).

Each polygon is in raster format and has a unique numeric identifier. Images
that include more than 256 unique polygons are stored in I*2 integer (16 bit)
format.

The attribute information that identifies or characterizes each polygon is
included under the \MISC directory. The attributes for the major land
resource area polygons are in LRAPOLY.ATT. The fields in the file are

polyid -- the unique polygon identification number
mlra -- the major land resource area (MLRA) identification code used by
the Soil Conservation Service
lratext -- text description of the MLRA used by the Soil Conservation
Service

The unique polygon identification number for the climatic division polygons
can be parsed into the State and climatic division number within that State.
For example, climatic district one in Arizona is polygon number 401. The 4 is
the Federal Information Processing Standard (FIPS) State identification number
for Arizona, and the 01 identifies the polygon as division one. Climatic
district one in Oklahoma is polygon number 4001, where 40 is the FIPS State
code and 01 is division one.


The attributes for the county polygons are in CTYPOLY.ATT. The fields in the
file are

cntyid -- the unique polygon identification number
npixels -- the number of pixels in each county
FIPS -- the FIPS State and county code for each county
cname -- the county name
sname -- the State name

One of the standard products calculated from the conterminous U.S. AVHRR data
set is a statistical summary of the NDVI, by county, for each composite
period. The statistical summaries for all 1994 compositing periods are
available on each of the discs. The statistical summary can be imported to a
spreadsheet and a graph can be created to show seasonal NDVI profiles. The
statistical summary is linked to the CTYPOLY image by the key attribute CNTYID
that is included in the CTYPOLY.ATT. This summary can be merged with the
CTYPOLY image for representation in image form.

The statistical summary for each composite period is stored in separate tables
with a standard naming convention (CNTYP01.DAT is the table for period 1,
CNTYP02.DAT for period 2, and so on). These tables are 80-character ASCII
files with the following attributes and format:
___________________________________________________________________________
Col # Fortran stmt. Description Definition
___________________________________________________________________________
1- 4 i4 CNTYID Unique identifier for
each county polygon
5-10 1x,i5 FIPS FIPS code
11-18 1x,f7.2 MEAN Mean NDVI (with clouds,
water, negative NDVI not
counted)
19-22 1x,i3 %USED The portion of all pixels
in county which are counted.
23-30 1x,f7.3 SD Standard deviation
31-34 1x,i3 MIN Minimum value in county
35-38 1x,i3 MAX Maximum value in county
39-46 1x,f7.2 MEDIAN Median value
47-50 1x,i3 MODE Mode value
51-54 1x,i3 PERIOD # Composite period number
___________________________________________________________________________

The NDVI statistics are calculated for each county after clouded pixels, water
bodies, and negative NDVI values (the 0 - 100 range of the scaled NDVI) are
masked out. The cloud screening is done independently (and is not applied to
image data on the CD-ROM) by using a threshold value of 240 for the sum of
channels 1 and 2 (values greater than 240 are considered clouds). The cloud-
screening technique includes an added indicator, the attribute %USED. The
attribute %USED represents the proportion of the pixels in a county (excluding
water bodies) that were counted in the computation. A low value in this
attribute can indicate cloud contamination.

Added to the miscellaneous image file was the surface water bodies mask.
These water bodies were separated using channel 2 from daily AVHRR scenes.
Cloud-free scenes were selected through a visual quality assessment of the
images. After a threshold between land and water values was identified, a
binary mask was computed and the water bodies data was added to a land
characteristic data base. Approximately 50 AVHRR scenes were used to create
the mask. Unique numeric identifiers were used in the raster formatted
polygons - water has the value of 0 and land has the value of 1.

Table 3. A list of miscellaneous image file characteristics
__________________________________________________________
Name Type Bands Lines Samples
__________________________________________________________
LRAPOLY I*2 1 2,889 4,587
LRALINES Byte 1 2,889 4,587
CDPOLY I*2 1 2,889 4,587
CDLINES Byte 1 2,889 4,587
CTYPOLY I*2 1 2,889 4,587
CTYLINES Byte 1 2,889 4,587
WATERMSK Byte 1 2,889 4,587
__________________________________________________________


CD-ROM ORGANIZATION

A large volume of data was generated during the construction of this data
base. The data stored on each CD-ROM required ten 6,250-bpi magnetic tapes.
The data are organized in a directory structure that logically separates the
data components. This structure is:

README.1ST
\AVHRR
README \LABELS \IMAGES
\NDVI
README \LABELS \IMAGES
\GEOM
README \LABELS \IMAGES
\MISC
README \LABELS \IMAGES \STATS
\DEMO
README
\SOFTWARE
README

Each directory on the disc contains data that are similar in type. Each
directory also contains an ASCII text file (README) that details the contents
of the directory.

The data files and LAS header files (files with name extensions .DDR) are in
the \IMAGES subdirectories, and the image label files are in the \LABELS
subdirectories. To get a quick start looking at the image files, label files
for each image are included in the \LABELS directory using the same file name
as the image file it describes in the \IMAGES subdirectory. These label files
were designed for use by the public domain MS-DOS personal computer IMDISP
image display software developed by NASA's Jet Propulsion Laboratory in
Pasadena, California. IMDISP users can access the images on this CD-ROM by
selecting the image name in the \LABELS subdirectory, which automatically
accesses the header information required by the software to retrieve the image
data. The data dimensions of each band are 2,889 lines and 4,587 samples (13
megabytes).

The \AVHRR directory contains the five channels of AVHRR data associated with
the four biweekly composites on each CD-ROM. Each band of each biweekly
composite file is uniquely named using the convention
P01CH1.IMG
where P01 identifies composite period 1 and CH1 identifies the image as
channel 1. The daily observations on the sixth disc are named using the same
convention, with D01 referring to the first daily observation. The image
files are stored in the \IMAGES subdirectory.

The \NDVI directory contains the single band computed NDVI for the biweekly
AVHRR composite data sets and is named using the convention:
P01NDVI.IMG
where P01 identifies composite period 1 and NDVI identifies the image as a
vegetation index image. The image files are stored in the \IMAGES
subdirectory.

The \GEOM directory contains the satellite and solar zenith and relative
azimuth information for each pixel in the AVHRR composite images. This
directory also contains the date images for each of the composites, as well as
the DATE.ATT attribute file.

The \MISC directory contains the political (CTYLINES, CTYPOLY), climatic
divisions (CDLINES, CDPOLY), and land resource area (LRALINES, LRAPOLY) raster
line and polygon images, which are useful for display or in digital analysis
procedures. Attribute files related to these are included as files
CTYPOLY.ATT and LRAPOLY.ATT. Each MISC directory also has a subdirectory,
STATS, which contains the NDVI statistics of all counties for each composite
period.

The \DEMO directory contains a batch job that runs under DOS and uses the
display program, IMDISP. This program displays images from the 1990
Conterminous U.S. AVHRR Biweekly Composites set. The display files are
compressed samples of these images. To initiate the demo program, enter
"DEMO" at the DOS prompt.

The \SOFTWARE directory contains programs to allow the PC-DOS user to display
and interact with the digital images on the CD's. These public domain
programs include

IMDISP - An image display program developed by NASA's Jet Propulsion
Laboratory. The most recent version is included on this disc. See
the IMDISP documentation file IMDISP.DOC, located in the \SOFTWARE
directory, and use the IMDISP help command for further details.

CONVERT - A conversion program included with IMDISP that allows the
conversion of a raster image to integer, byte, nibble, or binary
format.

COPIM - A copy program that allows copying all or portions of a raster
image and puts IMDISP compatible label records at the front of the
image.

COMBINE - A utility for combining two or more images as a single new image.
This utility has options to:

1. Combine up to three separate images into a single new
black-and-white image and also create a customized color
palette of up to 255 colors that, along with the new combined
image, allows a color simulation of a 3-band false color
composite image suitable for display on an 8-bit PC color
monitor; these colors are a very close approximation of how the
image would appear on a 24-bit color display.

2. Automatically "stretch" or brighten an existing palette.

3. Embed one image (such as raster linework) within
a second image.

The resultant images and palettes created by the COMBINE
utility are compatible with the IMDISP display program.
It takes approximately 4 minutes to process a 512 lines
by 512 samples, 3-image false color composite when the
input and output images are on hard disk. To run this
utility type COMBINE and respond to the prompts
requesting the input image names, output image name, and
output palette name.

LL2LAM - Converts latitude and longitude coordinates to Lambert Azimuthal
Equal Area projection coordinates.

LAM2LL - Converts Lambert Azimuthal Equal Area projection coordinates to
latitude and longitude coordinates.

LL2LS - Converts latitude and longitude to line and sample coordinates in
the Conterminous U.S. AVHRR data set. This data set is in the
Lambert Azimuthal Equal Area projection.

LS2LL - Converts line and sample coordinates in the Conterminous U.S.
AVHRR data set to latitude and longitude.

There are no restrictions on making copies of IMDISP or any of the other
public domain programs for use on other PC's or with other raster images.

* NOTE: Prior to displaying any of the following images with IMDISP, the
command "SET SWAP" must be run to reset the display for 16-bit
integer data. This command must be run after the image has been
selected with the IMDISP "FILES" command.

CTYPOLY.LBL - County polygon data
CDPOLY.LBL - Climatic polygon data
LRAPOLY.LBL - LRA polygon data
DEM.LBL - Digital elevation data

For more information please contact Customer Services, EROS Data Center, U.S.
Geological Survey, Sioux Falls, SD 57198, (605)594-6151, FAX (605)594-6589.


REFERENCES

Ailts, B., Akkerman, D., Quirk, B., and Steinwand, D., 1990, LAS 5.0 -- an
image processing system for research and production environments:
American Society for Photogrammetry and Remote Sensing-American Congress
on Surveying and Mapping Annual Convention, Denver, Colorado,
March 18-23, 1990, Proceedings, v. 4, p. 1-12.

Eidenshink, J.C., 1992, The 1990 conterminous U.S. AVHRR data set:
Photogrammetric Engineering and Remote Sensing, vol. 58, no. 6,
pp. 809-813.

Holben, B.N., 1986, Characteristics of maximum-value composite images from
temporal AVHRR data: The International Journal of Remote Sensing, v. 7,
no. 11, p. 1417.

Holben, B.N., Kaufman, Y.J., and Kendall, J.D., 1990, NOAA-11 AVHRR visible
and near-IR inflight calibration: The International Journal of Remote
Sensing, v. 11, no. 8, p. 1511.

Kidwell, K.B., 1991, NOAA Polar Orbiter Data Users' Guide: National Oceanic
and Atmospheric Administration, World Weather Building, Room 100,
Washington, D.C.

Price, John C., 1987, Calibration of satellite radiometers and the comparison
of vegetation indices: Remote Sensing of the Environment, v. 21, no.
15, pp. 15-27.

Rao, Nagaraja C. R., 1987, Pre-launch calibration of channels 1 and 2 of
Advanced Very High Resolution Radiometer: NOAA Technical Report NESDIS
36, Satellite Research Laboratory, National Environmental Satellite,
Data, and Information Service, Washington, D.C., 62 p.

Teillet, P.M. and Holben, B.N., 1994, Towards operational radiometric
calibration of NOAA-AVHRR imagery in the visible and infrared channels:
Canadian Journal of Remote Sensing, v.20, no.1, pp 1-10.

U.S. Department of Agriculture, Soil Conservation Service, 1981, Land resource
regions and major land resource areas of the United States: Agricultural
Handbook 296, 156 p.


Acknowledgments

A number of individuals contributed to the successful completion of the AVHRR
Conterminous U.S. composite data, including various operations staff and
digital data production scientists. Jesslyn F. Brown and Richard A. McKinney
provided excellent technical reviews.



Jeffery C. Eidenshink

Mary C. Weinheimer

Michael E. Madigan


##############################################################
VIII. APPENDIX II - Pixel Date Attribute Table


PERIOD INDEX SCENEID Date GMT
------ ----- ---------------- ------- --------
01 1 ah11010794231507 01-07-94 23:15:07
2 ah11010894230229 01-08-94 23:02:29
3 ah11010894212135 01-08-94 21:21:35
4 ah11010994224953 01-09-94 22:49:53
5 ah11011094223733 01-10-94 22:37:33
6 ah11011194222500 01-11-94 22:25:00
7 ah11011294235637 01-12-94 23:56:37
8 ah11011394234339 01-13-94 23:43:39
9 ah11010994210941 01-09-94 21:09:41
10 ah11011494233043 01-14-94 23:30:43
11 ah11011494214810 01-14-94 21:48:10
12 ah11011594213612 01-15-94 21:36:12
13 ah11011794225305 01-17-94 22:53:05
14 ah11011894224013 01-18-94 22:40:13
15 ah11011994204833 01-19-94 20:48:33
16 ah11012094235935 01-20-94 23:59:35
02 101 ah11021194224810 02-11-94 22:48:10
102 ah11021294223535 02-12-94 22:35:35
103 ah11021394222316 02-13-94 22:23:16
104 ah11021494235434 02-14-94 23:54:34
105 ah11021594215844 02-15-94 21:58:44
106 ah11021694214645 02-16-94 21:46:45
107 ah11021994211040 02-19-94 21:10:40
108 ah11022294203519 02-22-94 20:35:19
109 ah11022394234414 02-23-94 23:44:14
110 ah11022494233128 02-24-94 23:31:28
03 1 ah11030494233407 03-04-94 23:34:07
2 ah11030494215153 03-04-94 21:51:53
3 ah11030594232112 03-05-94 23:21:12
4 ah11030594213939 03-05-94 21:39:39
5 ah11030694230834 03-06-94 23:08:34
7 ah11030794225556 03-07-94 22:55:56
8 ah11030994223100 03-09-94 22:31:00
9 ah11031094221842 03-10-94 22:18:42
101 ah11031194234937 03-11-94 23:49:37
102 ah11031194220625 03-11-94 22:06:25
103 ah11031294233640 03-12-94 23:36:40
104 ah11031294215425 03-12-94 21:54:25
105 ah11031394232345 03-13-94 23:23:45
106 ah11031494231106 03-14-94 23:11:06
107 ah11031594225828 03-15-94 22:58:28
108 ah11031694210621 03-16-94 21:06:21
109 ah11031494213013 03-14-94 21:30:13
110 ah11031594211816 03-15-94 21:18:16
111 ah11031694224606 03-16-94 22:46:06
112 ah11031794223332 03-17-94 22:33:32
04 1 ah11031894222113 03-18-94 22:21:13
3 ah11031994235210 03-19-94 23:52:10
4 ah11032194214441 03-21-94 21:44:41
5 ah11032194232527 03-21-94 23:25:27
6 ah11032094233912 03-20-94 23:39:12
7 ah11032294213321 03-22-94 21:33:21
8 ah11032294231416 03-22-94 23:14:16
9 ah11032394212126 03-23-94 21:21:26
10 ah11032494224919 03-24-94 22:49:19
101 ah11032794235527 03-27-94 23:55:27
102 ah11032894234231 03-28-94 23:42:31
103 ah11032994232951 03-29-94 23:29:51
104 ah11032994214758 03-29-94 21:47:58
105 ah11033094213600 03-30-94 21:36:00
106 ah11033094231657 03-30-94 23:16:57
107 ah11033194212405 03-31-94 21:24:05
108 ah11033194230420 03-31-94 23:04:20
5 1 ah11040194211211 04-01-94 21:12:11
3 ah11040294210018 04-02-94 21:00:18
4 ah11040394222707 04-03-94 22:27:07
5 ah11040494235823 04-04-94 23:58:23
6 ah11040494221451 04-04-94 22:14:51
7 ah11040594234527 04-05-94 23:45:27
9 ah11040694233232 04-06-94 23:32:32
10 ah11040794213840 04-07-94 21:38:40
101 ah11040894212629 04-08-94 21:26:29
102 ah11040994225440 04-09-94 22:54:40
103 ah11041094224206 04-10-94 22:42:06
104 ah11041194222948 04-11-94 22:29:48
105 ah11041394234808 04-13-94 23:48:08
106 ah11041394220516 04-13-94 22:05:16
107 ah11041494233513 04-14-94 23:35:13
108 ah11041494215317 04-14-94 21:53:17
6 1 ah11041594232234 04-15-94 23:22:34
2 ah11041694230957 04-16-94 23:09:57
3 ah11041794225721 04-17-94 22:57:21
5 ah11041894224447 04-18-94 22:44:47
6 ah11041894210521 04-18-94 21:05:21
7 ah11041994223109 04-19-94 22:31:09
8 ah11042094001524 04-20-94 00:15:24
10 ah11042194220634 04-21-94 22:06:34
11 ah11042194234925 04-21-94 23:49:25
12 ah11042094221851 04-20-94 22:18:51
101 ah11042294215434 04-22-94 21:54:34
102 ah11042394214235 04-23-94 21:42:35
103 ah11042494213022 04-24-94 21:30:22
105 ah11042594225831 04-25-94 22:58:31
106 ah11042594211826 04-25-94 21:18:26
107 ah11042694224556 04-26-94 22:45:56
108 ah11042694210647 04-26-94 21:06:47
110 al11042994000224 04-29-94 00:02:24
7 1 ah11042994235154 04-29-94 23:51:54
2 ah11042994220901 04-29-94 22:09:01
3 ah11043094233857 04-30-94 23:38:57
4 ah11050194232616 05-01-94 23:26:16
5 ah11050294213249 05-02-94 21:32:49
6 ah11050294231337 05-02-94 23:13:37
8 ah11050494224823 05-04-94 22:48:23
10 ah11050594223603 05-05-94 22:36:03
11 ah11050694002035 05-06-94 00:20:35
101 ah11050994232843 05-09-94 23:28:43
102 ah11050994214712 05-09-94 21:47:12
104 ah11050794221127 05-07-94 22:11:27
105 ah11050794235421 05-07-94 23:54:21
107 ah11050894234124 05-08-94 23:41:24
108 ah11051094213514 05-10-94 21:35:14
109 ah11051094231603 05-10-94 23:16:03
110 ah11051194212317 05-11-94 21:23:17
111 ah11051194230325 05-11-94 23:03:25
112 ah11051294211122 05-12-94 21:11:22
8 1 ah11051394205944 05-13-94 20:59:44
2 ah11051494204752 05-14-94 20:47:52
3 ah11051494222712 05-14-94 22:27:12
4 ah11051594221352 05-15-94 22:13:52
5 ah11051594235647 05-15-94 23:56:47
6 ah11051694220152 05-16-94 22:01:52
7 ah11051694234350 05-16-94 23:43:50
8 ah11051794214936 05-17-94 21:49:36
9 ah11051794233108 05-17-94 23:31:08
10 ah11051994212541 05-19-94 21:25:41
102 ah11052094225313 05-20-94 22:53:13
103 ah11052194210152 05-21-94 21:01:52
104 ah11052194224053 05-21-94 22:40:53
106 ah11052294222834 05-22-94 22:28:34
107 ah11052394001236 05-23-94 00:12:36
108 ah11052394221616 05-23-94 22:16:16
109 ah11052494220414 05-24-94 22:04:14
110 ah11052294002551 05-22-94 00:25:51
111 ah11052594215159 05-25-94 21:51:59
112 ah11052594233331 05-25-94 23:33:31
113 ah11052694214000 05-26-94 21:40:00
114 ah11052694232051 05-26-94 23:20:51
9 1 ah11052794212803 05-27-94 21:28:03
2 ah11052794230813 05-27-94 23:08:13
3 ah11052894211607 05-28-94 21:16:07
4 ah11052894225535 05-28-94 22:55:35
5 ah11052994210413 05-29-94 21:04:13
6 ah11052994224315 05-29-94 22:43:15
7 ah11053094002813 05-30-94 00:28:13
8 ah11053094205235 05-30-94 20:52:35
9 ah11053094223055 05-30-94 22:30:55
10 ah11053194001449 05-31-94 00:14:49
11 ah11060194220636 06-01-94 22:06:36
12 ah11060194234851 06-01-94 23:48:51
13 ah11060294215420 06-02-94 21:54:20
14 ah11060294233554 06-02-94 23:35:54
101 ah11060394214222 06-03-94 21:42:22
102 ah11060394232314 06-03-94 23:23:14
103 ah11060494213024 06-04-94 21:30:24
104 ah11060494231553 06-04-94 23:15:53
107 ah11060794003028 06-07-94 00:30:28
108 ah11060794223317 06-07-94 22:33:17
109 ah11060894001712 06-08-94 00:17:12
110 ah11060894204320 06-08-94 20:43:20
111 ah11060894222059 06-08-94 22:20:59
112 ah11060994220857 06-09-94 22:08:57
113 ah11060994235113 06-09-94 23:51:13
10 1 ah11061094233816 06-10-94 23:38:16
2 ah11061194232535 06-11-94 23:25:35
3 ah11061194214442 06-11-94 21:44:42
4 ah11061094215641 06-10-94 21:56:41
5 ah11061294231256 06-12-94 23:12:56
6 ah11061294213244 06-12-94 21:32:44
7 ah11061394212048 06-13-94 21:20:48
9 ah11061494210853 06-14-94 21:08:53
11 ah11061594205715 06-15-94 20:57:15
13 ah11061694001933 06-16-94 00:19:33
14 ah11061694204538 06-16-94 20:45:38
15 ah11061694222318 06-16-94 22:23:18
101 ah11061794235334 06-17-94 23:53:34
103 ah11061994232756 06-19-94 23:27:56
104 ah11062094231516 06-20-94 23:15:16
105 ah11062094213503 06-20-94 21:35:03
106 ah11062194212305 06-21-94 21:23:05
107 ah11062194230252 06-21-94 23:02:52
108 ah11061894234036 06-18-94 23:40:36
109 ah11061894215901 06-18-94 21:59:01
111 ah11062394003524 06-23-94 00:35:24
112 ah11062294211110 06-22-94 21:11:10
114 ah11062494002206 06-24-94 00:22:06
11 2 ah11062594221333 06-25-94 22:13:33
5 ah11062794214916 06-27-94 21:49:16
6 ah11062794233012 06-27-94 23:30:12
7 ah11062894213718 06-28-94 21:37:18
8 ah11062894231732 06-28-94 23:17:32
9 ah11062994230509 06-29-94 23:05:09
10 ah11063094225232 06-30-94 22:52:32
11 ah11070194003742 07-01-94 00:37:42
103 ah11070294222753 07-02-94 22:27:53
104 ah11070294002425 07-02-94 00:24:25
106 ah11070394235809 07-03-94 23:58:09
107 ah11070394001109 07-03-94 00:11:09
108 ah11070494220334 07-04-94 22:03:34
109 ah11070494234526 07-04-94 23:45:26
110 ah11070594233230 07-05-94 23:32:30
111 ah11070594215134 07-05-94 21:51:34
113 ah11070694232425 07-06-94 23:24:25
114 ah11070194210132 07-01-94 21:01:32
12 3 ah11071094223007 07-10-94 22:30:07
4 ah11071194221804 07-11-94 22:18:04
5 ah11071294220547 07-12-94 22:05:47
6 ah11071294234740 07-12-94 23:47:40
7 ah11071394215346 07-13-94 21:53:46
8 ah11071394233459 07-13-94 23:34:59
9 ah11071494232218 07-14-94 23:22:18
10 ah11071494214132 07-14-94 21:41:32
11 ah11070894211543 07-08-94 21:15:43
101 ah11071594212935 07-15-94 21:29:35
102 ah11071594230939 07-15-94 23:09:39
105 ah11071794224529 07-17-94 22:45:29
108 al11072094000051 07-20-94 00:00:51
109 ah11072094234955 07-20-94 23:49:55
110 ah11071694211754 07-16-94 21:17:54
111 ah11072194233713 07-21-94 23:37:13
112 ah11072094220801 07-20-94 22:08:01
13 1 ah11072294232432 07-22-94 23:24:32
2 ah11072394213148 07-23-94 21:31:48
3 ah11072394231153 07-23-94 23:11:53
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