The Global Inventory Modeling and Mapping (GIMMS) group at NASA/GSFC provided SAFARI 2000 with remotely sensed satellite data products at the site and regional level. These Advanced Very High Resolution Radiometer (AVHRR) data contain two main sets of data: site extracts of SAFARI core sites (Mongu, Etosha, Kasungu, Maun, Skukuza, and Tshane) and regional 15-day composites from sets of single-day images. These AVHRR data contain four main sets of data:
1.5-km daily site extracts of SAFARI core sites (2000)
1.5-km 15-day composites of SAFARI core sites (1998-2000)
1.5-km 15-day composites of the southern African region (March, September 2000)
6-km 15-day composites of the southern African region (1998-2000)
The primary data layers for site extracts and regional composites are fire pixel counts and maximum normalized difference vegetation index (NDVI). The fire product is different for the daily and for the composited products (see readme file) and a fire product is not included in the 1.5-km regional data set. NDVI composite-associated data layers for the regional data sets include land surface temperature, reflectance, solar zenith angle, view zenith angle, and relative azimuth angle. NDVI composite-associated data layers for the site extracts include these same variables as well as brightness temperature, fire mask composite, latitude, and longitude.
The data are stored in binary image format files. There is a metadata file for each site and date/compositing period, in ASCII format.
Cite this data set as follows:
Tucker, C. J., A. S. Morahan, and J. Kendall. 2005. SAFARI 2000 AVHRR Daily Site (1.5 km) and 15-Day Regional (1.5- and 6-km) Imagery. Data set. Available on-line [http://daac.ornl.gov/] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. doi:10.3334/ORNLDAAC/822.
El Saleous, N. Z., E. F. Vermote, C. O. Justice, J. R. Townshend, C. J. Tucker, and S. N. Goward. 2000. Improvements in the global biospheric record from the Advanced Very High Resolution Radiometer (AVHRR). International Journal of Remote Sensing, 21(6-7): 1251-1277.
Townshend, J. (ed.). 1995. Global data sets for the land from AVHRR. International Journal of Remote Sensing, 15: 3315-3639 (special issue describing several program-generating composite AVHRR image data sets).
The images are all flat binary files, the number of bits per pixel are given in the metadata files, as are the image sizes, also given below. There is a metadata file for each site and date/compositing period, in ASCII format.
6 km Regional Composites
515 image rows
639 image columns
1.5 km Regional Composites
2060 image rows
2556 image columns
Site Extracts, Daily and Composites
150 image rows
150 image columns
The bands contained within each image product are:
6 km and 1.5 km Regional Composites
Primary Data Layers
| ID | Description | BITS | UNITS | SCALE | OFFSET | SPECIAL |
| FIRE | Fire Pixel Count | 8 | -- | 1.0 | 0 | X=640 Y=752 *(6 km only) |
| NDVI | Median 1.5-Km Max NDVI | 16 | -- | 0.001 | 0 |
|
NDVI Composite-Associated Data Layers
| ID | Description | BITS | UNITS | SCALE | OFFSET |
| LST | Land Surface Temperature | 16 | Kelvin | 0.1 | 0 |
| R1 | Reflectance Channel 1 | 16 | percent | 0.01 | 0 |
| R2 | Reflectance Channel 2 | 16 | percent | 0.01 | 0 |
| TS | Solar Zenith Angle | 16 | percent | 0.01 | 0 |
| TV | View Zenith Angle | 16 | percent | 0.01 | 0 |
| PHI | Relative Azimuth Angle | 16 | percent | 0.01 | 0 |
Site Extract Composites
Primary Data Layers
| ID | Description | BITS | UNITS | SCALE | OFFSET | NOTE |
| FIRE | Fire Pixel Count | 8 | -- | 0.1 | 0 | |
| NDVI | Maximum NDVI | 16 | -- | 0.001 | 0 | |
| LAT | Latitude | 32 | -- | -- | -- | signed integer |
| LON | Longitude | 32 | -- | -- | -- | signed integer |
NDVI Composite-Associated Data Layers
| ID | Description | BITS | UNITS | SCALE | OFFSET |
| LST | Land Surface Temperature | 16 | Kelvin | 0.1 | 0 |
| R1 | Reflectance Channel 1 | 16 | percent | 0.01 | 0 |
| R2 | Reflectance Channel 2 | 16 | percent | 0.01 | 0 |
| TS | Solar Zenith Angle | 16 | percent | 0.01 | 0 |
| TV | View Zenith Angle | 16 | percent | 0.01 | 0 |
| PHI | Relative Azimuth Angle | 16 | percent | 0.01 | 0 |
| DAY | Composite Day Index | 8 | -- | -- | -- |
Site Extract Daily
| ID | Description | BITS | UNITS | SCALE | OFFSET | NOTE |
| LST | Land Surface Temperature | 16 | Kelvin | 0.1 | 0 | |
| R1 | Reflectance Channel 1 | 16 | percent | 0.01 | 0 | |
| R2 | Reflectance Channel 2 | 16 | percent | 0.01 | 0 | |
| T3 | Brightness Temperature Channel 3 | 16 | Kelvin | 0.01 | 0 | |
| T4 | Brightness Temperature Channel 4 | 16 | Kelvin | 0.01 | 0 | |
| T5 | Brightness Temperature Channel 5 | 16 | Kelvin | 0.01 | 0 | |
| TS | Solar Zenith Angle | 16 | degrees | 0.01 | 0 | |
| TV | View Zenith Angle | 16 | degrees | 0.01 | 0 | |
| PHI | Relative Azimuth Angle | 16 | degrees | 0.01 | 0 | |
| NDVI | Maximum NDVI | 16 | -- | 0.001 | 0 | |
| LST | Land Surface Temperature | 16 | Kelvin | 0.01 | 0 | |
| FIRE | Fire Mask Composite | 8 | -- | -- | -- | |
| LAT | Latitude | 32 | -- | -- | -- | signed integer |
| LON | Longitude | 32 | -- | -- | -- | signed integer |
Fire Mask Classes:
0 missing
1 water
2 cloud
3 no fire (and not even a potential fire)
4 no fire (but was a potential fire)
5 unknown
6 fire (low confidence)
7 fire (nominal confidence)
8 fire (high confidence)
Additional information about the AVHRR parameters/variables, AVHRR data manipulations, and sensor/instrument description is found in the companion file: http://daac.ornl.gov/daacdata/safari2k/remote_sensing/avhrr/comp/avhrr_site_regional_imagery_readme.pdf.
2005/6/29
2005/6/29
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