Sevilleta National Wildlife Refuge, near Albuquerque, New Mexico

\log

12/19/97 - 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 (1989)


##############################################################
ABSTRACT
This dataset contains 21 separate 14-day composited AVHRR
images for 1989, and the first 2 separate 14-day composited AVHRR
images for 1990, 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.


##############################################################
KEYWORDS
SEV031 AVHRR Advanced_Very_High_Resolution_Radiometer NOAA Satellite_Imagery Remote_Sensing USGS_EROS_Data_Center 1989 1990


##############################################################
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

Twenty-one 14-day composites for 1989, and the first two 14-day
composites for 1990. 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 21 NULL bytes onto the last line of each band, 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 89

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

avhrr89pPP.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->avhrr89pPP.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 avhrr89pPP.img avhrr89pPPnm.img

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

avhrr89pPPnm.img

5. Unix compress the NM clipped image, make an archive directory, and move it
to the archive destination (/db/archive/imagery/avhrr/avhrr89pPP/). 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:

avhrr89pPPnm.img.Z

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

gzip avhrr89pPP.img
mt -f /dev/rmt/0cn fsf <#>
tar cvf /dev/rmt/0cn avhrr89pPP.img.gz
rm avhrr89pPP.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 (avhrr89.dbf) for the images
(note, must also convert from DOS to Unix file):

dos2unix /cdrom/cdrom0/readme.1st avhrr89readme.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
(avhrr89pPPnm.mda), and merge by year for inclusion in SIMS IAF metadata
file (avhrr89.dbf):

dos2unix /cdrom/cdrom0/geom/date.att avhrr89pPP-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 89 > avhrr89date.att

9. Generate (this) SIMS IAF metadata file (i.e., avhrr89.dbf) using template
file (avhrr_dbf.tmpl), appending readme file (avhrr89readme.1st), and date
file (avhrr89date.att).

10. Generate GIS/RS Metadata Abstract file for each image, and put with
image in appropriate directory (/db/archive/imagery/avhrr/avhrr89pPP/):

/db/local/imagery/bincom/get_avhrr_dates.csh 89 avhrr89.dbf 97 \
> avhrr89periods.txt

/db/local/imagery/bincom/batch_make_avhrr_abstract.csh avhrr89periods.txt
which calls:
/db/local/imagery/bincom/make_avhrr_abstract.csh


##############################################################
VII. APPENDIX I - USGS EDC Metadata

THE 1989 CONTERMINOUS U.S. AVHRR BIWEEKLY COMPOSITES

TABLE OF CONTENTS

Introduction . . . . . . . . . . . . . . . . . . . . . . . .Page 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 . . . . . . . . . . . . . . . . . . . . . 9
Geometric Registration. . . . . . . . . . . . . . . . . . . .10
Compositing . . . . . . . . . . . . . . . . . . . . . . . . .12
Miscellaneous Data. . . . . . . . . . . . . . . . . . . . . .13
CD-ROM Organization. . . . . . . . . . . . . . . . . . . . . . .18
References . . . . . . . . . . . . . . . . . . . . . . . . . . .23


THE 1989 CONTERMINOUS U.S. AVHRR BIWEEKLY COMPOSITES

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 meximum NDVI composites. These data are being
published on CD-ROM for easy 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 condition, and provides a foundation for studying
long-term changes resulting from human or natural factors.



DATA SET CHARACTERISTICS

The data set is composed of twenty-one 14-day maximum NDVI composites that were
created from nearly 400 NOAA-11 images and three single date images. The 17
core composite periods represent a continuous period from March 1, 1989, to
October 24, 1989. The first two (periods 1 and 2) and last two (periods 20
and 21) composites represent a 2-week period each for January, February,
November, and December. The 1989 data set is available as six CD-ROM's. Each
of the first five discs has four biweekly composites and miscellaneous data
which are described later in this file. The sixth disc of the 1989 CD-ROM
series contains the December 1989 2-week composite, the first and second 2-week
periods of 1990, and NDVI statistics of all counties in the conterminous United
States for each composite period. The 1990 naming convention used for these
two periods follow in numeric sequence to the 1989 scenes.

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 1989 were:
___________________________________________________________________
Period Date of coverage Julian day
___________________________________________________________________

1 01/04 - 01/17/1989 004 - 017
2 02/01 - 02/14/1989 032 - 045
3 03/01 - 03/14/1989 060 - 073
4 03/15 - 03/28/1989 074 - 087
5 03/29 - 04/11/1989 088 - 101
6 04/12 - 04/25/1989 102 - 115
7 04/26 - 05/09/1989 116 - 129
8 05/10 - 05/23/1989 130 - 143
9 05/24 - 06/06/1989 144 - 157
10 06/07 - 06/20/1989 158 - 171
11 06/21 - 07/04/1989 172 - 185
12 07/05 - 07/18/1989 186 - 199
13 07/19 - 08/01/1989 200 - 213
14 08/02 - 08/15/1989 214 - 227
15 08/16 - 08/29/1989 228 - 241
16 08/30 - 09/12/1989 242 - 255
17 09/13 - 09/26/1989 256 - 269
18 09/27 - 10/10/1989 270 - 283
19 10/11 - 10/24/1989 284 - 297
20 11/01 - 11/14/1989 305 - 318
21 12/06 - 12/19/1989 340 - 353
___________________________________________________________________

The image dimensions of each band are 2,889 lines and 4,608 samples (13
megabytes).



The 14-day composite periods for 1990 on the sixth disc were:
--------------------------------------------------------------------
Period Date of coverage Julian day
22 01/05 - 01/18/1990 005 - 018
23 02/02 - 02/15/1990 033 - 046
--------------------------------------------------------------------
The image dimensions of each band are 2,889 lines and 4,603 samples (13
megabytes).


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, like 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 non-vegetated 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 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 input 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 are rasterized to 1-km cells and registered to the Lambert
Azimuthal Equal Area map 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 1.0 pixel). The segments are digitally mosaicked to produce a single
base image of the conterminous United States for registering the 1989 growing
season data. The accuracy of this base image is verified with a
root-mean-square error less than 1.0 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 (1989)
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 latitude and longitude:
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 latitude and longitude:
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 1989 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 input 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 form 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
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 output 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), and county boundaries (CTYLINES). 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.

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 1989 compositing periods are available on
the sixth disc. The statistical summary can be imported to a spreadsheet and
graphed 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 is not foolproof so an added indicator, the attribute
%USED, is also included. 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.

Table 3. A list of miscellaneous image file characteristics
__________________________________________________________

Name Type Bands Lines Samples
__________________________________________________________

LRAPOLY I*2 1 2,889 4,608
LRALINES Byte 1 2,889 4,608
CDPOLY I*2 1 2,889 4,608
CDLINES Byte 1 2,889 4,608
CTYPOLY I*2 1 2,889 4,608
CTYLINES Byte 1 2,889 4,608
WATERMSK Byte 1 2,889 4,608
__________________________________________________________
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
\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. The binary image files were put on the CD-ROM with a 512-byte
header record. This header record is used by the LAS image processing system.
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, CA. 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 actual data dimensions of each band are 2,889 lines and 4,587 samples (13
megabytes), but the images are stored as 2,889 lines and 4,608 samples to
accommodate LAS software. The last 21 samples of each line are blank (zero) to
make each line a multiple of 512 as required by LAS, with the exception of the
last line. The images were generated on a UNIX-based system. On UNIX systems,
the portion of the last block does not exist; therefore, lines 1-2,888 contain
4,608 samples and line 2,889 has 4,587 samples. The formula to calculate the
number of disc blocks for an image in a UNIX environment is

#image_bytes_line = #samps * #bytes_samp
#bytes_file_line = INT(((#image_bytes_line - 1) / 512) + 1) * 512
#bytes_file = (#lines * #bytes_file_line * #nbands) -
(#bytes_file_line - #image_bytes_line) + 512

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 sixth disc contains the December 2-week composite
period P21NDVI and the three daily observations D01 - D03. 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.

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, just 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.

COMPOSIT - A utility for combining or compositing 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 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 COMPOSIT utility are
compatible with the IMDISP display program. It takes approximately 4
minutes to process a 512 lines by 512 samples, 3-image composite when
the input and output images are on hard disk. To run this utility
type COMPOSIT 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 detailed technical 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., 1991, unpublished report.

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.



Acknowledgements

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. Richard A. McKinney and Jesslyn F. Brown provided
excellent technical reviews.



Jeffery C. Eidenshink
Michael E. Madigan
Mary C. Weinheimer


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


PERIOD INDEX SCENEID Date GMT
------ ----- ---------------- ------- --------
1 1 ah11010489193950 01-04-89 19:39:50
2 ah11010489175850 01-04-89 17:58:50
3 ah11010589174910 01-05-89 17:49:10
4 ah11011289200050 01-12-89 20:00:50
5 ah11011489175910 01-14-89 17:59:10
6 ah11011589211210 01-15-89 21:12:10
7 ah11011689192000 01-16-89 19:20:00
8 ah11010989203100 01-09-89 20:31:00
9 ah11011789191000 01-17-89 19:10:00
2 101 ah11020189181910 02-01-89 18:19:10
102 ah11020889184920 02-08-89 18:49:20
103 ah11020489211300 02-04-89 21:13:00
104 ah11020789205130 02-07-89 20:51:30
105 ah11020889203120 02-08-89 20:31:20
3 1 ah11030689192900 03-06-89 19:29:00
2 ah11030389181740 03-03-89 18:17:40
3 ah11030789210020 03-07-89 21:00:20
101 ah11030989185820 03-09-89 18:58:20
102 ah11031089184800 03-10-89 18:48:00
103 ah11031189183740 03-11-89 18:37:40
104 ah11031289182740 03-12-89 18:27:40
105 ah11031489194830 03-14-89 19:48:30
106 ah11031389181700 03-13-89 18:17:00
4 1 ah11031589193830 03-15-89 19:38:30
2 ah11031689192830 03-16-89 19:28:30
3 ah11032089202900 03-20-89 20:29:00
4 ah11032189201820 03-21-89 20:18:20
5 ah11031789205930 03-17-89 20:59:30
101 ah11032289200800 03-22-89 20:08:00
102 ah11032389200030 03-23-89 20:00:30
103 ah11032589193930 03-25-89 19:39:30
104 ah11032689192930 03-26-89 19:29:30
105 ah11032889190620 03-28-89 19:06:20
5 1 ah11040289181450 04-02-89 18:14:50
2 ah11040289195610 04-02-89 19:56:10
3 ah11040189200640 04-01-89 20:06:40
4 ah11033089202730 03-30-89 20:27:30
5 ah11040489211750 04-04-89 21:17:50
101 ah11041189200540 04-11-89 20:05:40
102 ah11041089201550 04-10-89 20:15:50
103 ah11040989202610 04-09-89 20:26:10
104 ah11040589210720 04-05-89 21:07:20
105 ah11040789205650 04-07-89 20:56:50
106 ah11040589192540 04-05-89 19:25:40
107 ah11040889203630 04-08-89 20:36:30
6 1 ah11041889203330 04-18-89 20:33:30
2 ah11041689191400 04-16-89 19:14:00
3 ah11041589192410 04-15-89 19:24:10
4 ah11041489193440 04-14-89 19:34:40
5 ah11041389212650 04-13-89 21:26:50
101 ah11041989202320 04-19-89 20:23:20
102 ah11042089183220 04-20-89 18:32:20
103 ah11042189182220 04-21-89 18:22:20
104 ah11042289195310 04-22-89 19:53:10
105 ah11042089201300 04-20-89 20:13:00
106 ah11042489193250 04-24-89 19:32:50
107 ah11042589192220 04-25-89 19:22:20
7 1 ah11042989202130 04-29-89 20:21:30
2 ah11043089201140 04-30-89 20:11:40
3 ah11050189200120 05-01-89 20:01:20
4 ah11050289195100 05-02-89 19:51:00
5 ah11042789204200 04-27-89 20:42:00
101 ah11050689191010 05-06-89 19:10:10
102 ah11050589192040 05-05-89 19:20:40
103 ah11050989202040 05-09-89 20:20:40
104 ah11050989183900 05-09-89 18:39:00
105 ah11050389212300 05-03-89 21:23:00
106 ah11050489211250 05-04-89 21:12:50
107 ah11050889184930 05-08-89 18:49:30
108 ah11050489175040 05-04-89 17:50:40
109 ah11050689205040 05-06-89 20:50:40
110 ah11042989202130 04-29-89 20:21:30
111 ah11043089201140 04-30-89 20:11:40
112 ah11042789204200 04-27-89 20:42:00
113 ah11050889203000 05-08-89 20:30:00
114 ah11050289195100 05-02-89 19:51:00
8 1 ah11051089201020 05-10-89 20:10:20
2 ah11051189195940 05-11-89 19:59:40
3 ah11051389193920 05-13-89 19:39:20
4 ah11051689190810 05-16-89 19:08:10
5 ah11051589210020 05-15-89 21:00:20
6 ah11051389212100 05-13-89 21:21:00
101 ah11052289194700 05-22-89 19:47:00
102 ah11051789203900 05-17-89 20:39:00
103 ah11052089200740 05-20-89 20:07:40
104 ah11052289212930 05-22-89 21:29:30
9 1 ah11052789185530 05-27-89 18:55:30
2 ah11052889184510 05-28-89 18:45:10
3 ah11053089200730 05-30-89 20:07:30
4 ah11052489210820 05-24-89 21:08:20
5 ah11052589205750 05-25-89 20:57:50
6 ah11052789203630 05-27-89 20:36:30
7 ah11052689204740 05-26-89 20:47:40
101 ah11053189213740 05-31-89 21:37:40
102 ah11060189212710 06-01-89 21:27:10
103 ah11060189194700 06-01-89 19:47:00
104 ah11060189180410 06-01-89 18:04:10
105 ah11060289211640 06-02-89 21:16:40
106 ah11060289175420 06-02-89 17:54:20
107 ah11060389210600 06-03-89 21:06:00
108 ah11060389174410 06-03-89 17:44:10
109 ah11060589204430 06-05-89 20:44:30
110 ah11060589190340 06-05-89 19:03:40
111 ah11060689185310 06-06-89 18:53:10
112 ah11060689203500 06-06-89 20:35:00
10 1 ah11060789202440 06-07-89 20:24:40
2 ah11060789184240 06-07-89 18:42:40
3 ah11060889201420 06-08-89 20:14:20
4 ah11060889183210 06-08-89 18:32:10
5 ah11060989200350 06-09-89 20:03:50
6 ah11061089213520 06-10-89 21:35:20
7 ah11061089195300 06-10-89 19:53:00
8 ah11061089181150 06-10-89 18:11:50
9 ah11061189194300 06-11-89 19:43:00
10 ah11061189180150 06-11-89 18:01:50
11 ah11061289211420 06-12-89 21:14:20
12 ah11061289175200 06-12-89 17:52:00
13 ah11061389210340 06-13-89 21:03:40
14 ah11061389192150 06-13-89 19:21:50
15 ah11061289193240 06-12-89 19:32:40
101 ah11061489205330 06-14-89 20:53:30
102 ah11061489191300 06-14-89 19:13:00
103 ah11061689203200 06-16-89 20:32:00
104 ah11061789202200 06-17-89 20:22:00
105 ah11061889201240 06-18-89 20:12:40
106 ah11061789184020 06-17-89 18:40:20
107 ah11061889182950 06-18-89 18:29:50
108 ah11061989200130 06-19-89 20:01:30
109 ah11061989181930 06-19-89 18:19:30
110 ah11062089213300 06-20-89 21:33:00
111 ah11062089195100 06-20-89 19:51:00
112 ah11061589204230 06-15-89 20:42:30
11 1 ah11062189212220 06-21-89 21:22:20
2 ah11062189194130 06-21-89 19:41:30
3 ah11062189175940 06-21-89 17:59:40
4 ah11062289211150 06-22-89 21:11:50
5 ah11062289174930 06-22-89 17:49:30
6 ah11062389210110 06-23-89 21:01:10
7 ah11062389192210 06-23-89 19:22:10
8 ah11062389173910 06-23-89 17:39:10
9 ah11062489190930 06-24-89 19:09:30
10 ah11062589203910 06-25-89 20:39:10
11 ah11062589185830 06-25-89 18:58:30
12 ah11062689202910 06-26-89 20:29:10
13 ah11062689184810 06-26-89 18:48:10
14 ah11062789183740 06-27-89 18:37:40
101 ah11062989214030 06-29-89 21:40:30
102 ah11062989195900 06-29-89 19:59:00
103 ah11063089195000 06-30-89 19:50:00
104 ah11063089180700 06-30-89 18:07:00
105 ah11070189211930 07-01-89 21:19:30
106 ah11070189193930 07-01-89 19:39:30
107 ah11070189175700 07-01-89 17:57:00
108 ah11070289210840 07-02-89 21:08:40
109 ah11070289192820 07-02-89 19:28:20
110 ah11070289174650 07-02-89 17:46:50
111 ah11070389205810 07-03-89 20:58:10
112 ah11070389191800 07-03-89 19:18:00
113 ah11070389173620 07-03-89 17:36:20
114 ah11070489204800 07-04-89 20:48:00
115 ah11070489190700 07-04-89 19:07:00
12 1 ah11070589203630 07-05-89 20:36:30
2 ah11070589185540 07-05-89 18:55:40
3 ah11070689202600 07-06-89 20:26:00
4 ah11070689184510 07-06-89 18:45:10
5 ah11070789201600 07-07-89 20:16:00
6 ah11070789183500 07-07-89 18:35:00
7 ah11070889200600 07-08-89 20:06:00
8 ah11070889182440 07-08-89 18:24:40
9 ah11070989213740 07-09-89 21:37:40
10 ah11070989195600 07-09-89 19:56:00
11 ah11071089212650 07-10-89 21:26:50
12 ah11071089194530 07-10-89 19:45:30
13 ah11071089180410 07-10-89 18:04:10
14 ah11071189211640 07-11-89 21:16:40
15 ah11071189193600 07-11-89 19:36:00
16 ah11071189175420 07-11-89 17:54:20
101 ah11071289210600 07-12-89 21:06:00
102 ah11071289174410 07-12-89 17:44:10
103 ah11071489204520 07-14-89 20:45:20
104 ah11071489190330 07-14-89 19:03:30
105 ah11071889200400 07-18-89 20:04:00
106 ah11071289192500 07-12-89 19:25:00
107 ah11071389205550 07-13-89 20:55:50
108 ah11071589203330 07-15-89 20:33:30
109 ah11071689202500 07-16-89 20:25:00
110 ah11071789201400 07-17-89 20:14:00
111 ah11071889182140 07-18-89 18:21:40
13 1 ah11071989213450 07-19-89 21:34:50
2 ah11071989195400 07-19-89 19:54:00
3 ah11071989181130 07-19-89 18:11:30
4 ah11072089212410 07-20-89 21:24:10
5 ah11072089194400 07-20-89 19:44:00
6 ah11072189211350 07-21-89 21:13:50
7 ah11072189193330 07-21-89 19:33:30
8 ah11072189175130 07-21-89 17:51:30
8 ah11072189175130 07-21-89 17:51:30
9 ah11072289192300 07-22-89 19:23:00
10 ah11072289174110 07-22-89 17:41:10
11 ah11072489204220 07-24-89 20:42:20
12 ah11072489190020 07-24-89 19:00:20
13 ah11072589203030 07-25-89 20:30:30
14 ah11072589185000 07-25-89 18:50:00
101 ah11072689202200 07-26-89 20:22:00
102 ah11072689183930 07-26-89 18:39:30
103 ah11072789201200 07-27-89 20:12:00
104 ah11072789182900 07-27-89 18:29:00
105 ah11072889214220 07-28-89 21:42:20
106 ah11072889200100 07-28-89 20:01:00
107 ah11072889181840 07-28-89 18:18:40
108 ah11072989213150 07-29-89 21:31:50
109 ah11072989180840 07-29-89 18:08:40
110 ah11073089212120 07-30-89 21:21:20
111 ah11073089194200 07-30-89 19:42:00
112 ah11073189211030 07-31-89 21:10:30
113 ah11073189193100 07-31-89 19:31:00
114 ah11073189174820 07-31-89 17:48:20
115 ah11080189210000 08-01-89 21:00:00
116 ah11080189191930 08-01-89 19:19:30
117 ah11072989195130 07-29-89 19:51:30
118 ah11080189173810 08-01-89 17:38:10
14 1 ah11080289204940 08-02-89 20:49:40
2 ah11080289190930 08-02-89 19:09:30
3 ah11080389203910 08-03-89 20:39:10
4 ah11080389185720 08-03-89 18:57:20
5 ah11080489202730 08-04-89 20:27:30
6 ah11080489184650 08-04-89 18:46:50
7 ah11080589201820 08-05-89 20:18:20
8 ah11080589183630 08-05-89 18:36:30
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113 ah11021490213700 02-14-90 21:37:00



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