EDG Data Set Name |
Granule Shortname |
MODIS/Aqua Vegetation Indices 16-Day L3 Global 1km SIN Grid |
MYD13A2 |
Version |
Acquisition Range |
Science Quality Status |
V003 |
March 6 2003 (2003065) - February 1 2004 (2004032) |
Provisional |
V004 |
July 4 2002 (2002185) |
Provisional |
MODIS Level 3 Tile h08v05, July 12 2002
Data Set Characteristics
Area = ~ 10° x 10° lat/long
Image Dimensions = 2 (1200x1200 row/column)
Average File Size = 32 MB
Resolution = 1 km
Projection = Sinusoidal
Data Format = HDF-EOS
Science Data Sets (SDSs) = 11
Product Description
The MYD13A2 image shown is a sample of the MODIS Level 3 16-day composite of Vegetation Indices at 1km resolution that has been pseudo-colored. This product uses, as input, MODIS Aqua surface reflectances, corrected for molecular scattering, ozone absorption, and aerosols. Two vegetation index (VI) algorithms are produced globally for land. One is the standard normalized difference vegetation index (NDVI), which is referred to as the "continuity index" to the existing NOAA-AVHRR derived NDVI. The other is an 'enhanced' vegetation index with improved sensitivity into high biomass regions and improved vegetation monitoring through a de-coupling of the canopy background signal and a reduction in atmosphere influences. The two VIs compliment each other in global vegetation studies and improve upon the extraction of canopy biophysical parameters. A new compositing scheme that reduces angular, sun-target-sensor variations is also utilized. The gridded vegetation indices will include quality assurance (QA) flags with statistical data that indicate the quality of the VI product and input data. Due to their simplicity, ease of application, and widespread familiarity, vegetation indices have a wide range of use within the user community. Some of the more common applications may include global biogeochemical and hydrologic modeling, agricultural monitoring and forecasting, land-use planning, land cover characterization, and land cover change detection.
NOTE: These products are still experimental in nature upon their initial release. Investigations are underway to assess the scientific validity of these products.
Each VI product contains 11 parameters, listed below:
SDS |
Units |
Data Type-bit |
Fill Value |
Valid Range |
Divide by SCALE FACTOR |
1km 16 days NDVI |
NDVI |
16-bit signed integer |
-3000 |
-2000 - 10000 |
10000 |
1km 16 days EVI |
EVI |
16-bit signed integer |
-3000 |
-2000 - 10000 |
10000 |
*1km 16 days NDVI Quality |
bit field |
16-bit unsigned integer |
65535 |
0 - 65535 |
na |
*1km 16 days EVI Quality |
bit field |
16-bit unsigned integer |
65535 |
0 - 65535 |
na |
1km 16 days red reflectance MODIS Band # 1, 620 - 670 nm |
reflectance |
16-bit signed integer |
-1000 |
0 - 10000 |
10000 |
1km 16 days NIR reflectance MODIS Band # 2, 841- 876 nm |
reflectance |
16-bit signed integer |
-1000 |
0 - 10000 |
10000 |
1km 16 days blue reflectance MODIS Band # 3, 459 - 479 nm |
reflectance |
16-bit signed integer |
-1000 |
0 - 10000 |
10000 |
1km 16 days MIR reflectance MODIS Band # 7, 2105-2155 nm |
reflectance |
16-bit signed integer |
-1000 |
0 - 10000 |
10000 |
1km 16 days average view zenith angle View zenith of the chosen pixel |
degree |
16-bit signed integer |
-10000 |
-9000 - 9000 |
100 |
1km 16 days average sun zenith angle Sun zenith of the chosen pixel |
degree |
16-bit signed integer |
-10000 |
-9000 - 9000 |
100 |
1km 16 days average relative azimuth angle Relative Azimuth of the chosen pixel |
degree |
16-bit signed integer |
-4000 |
-3600 - 3600 |
10 |
*Quality Control Bit Index
Bit |
Description |
0-1 |
NDVI quality |
|
00 NDVI produced, good quality; |
|
01 NDVI produced, but check QA |
|
10 produced but most likely cloudy pixel |
|
11 pixel not produced due to other reasons than clouds |
2-5 |
VI usefulness four bit range 0= highest quality |
|
13 no atmospheric correction performed |
|
14 quality too low to be useful |
|
15 not useful for any other reason |
6-7 |
aerosol quantity: |
|
00 climatology |
|
01 low |
|
10 average |
|
11 high |
8 |
1 yes adjacency correction performed |
|
0 no adjacency correction performed |
9 |
1 yes atmosphere BRDF correction performed |
|
0 no atmosphere BRDF correction performed |
10 |
1 yes mixed clouds |
|
0 no mixed clouds |
11-12 |
land/water flag |
|
00 ocean |
|
01 coast |
|
10 wetland |
|
11 land |
13 |
1 yes possible snow/ice |
|
0 no possible snow/ice |
14 |
1 yes possible shadow |
|
0 no possible shadow |
15 |
composite method for NDVI |
|
0 BRDF model based nadir equivalent VI |
|
1 CVMVC (constraint view angle maximum value VI) |
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Retrieve the MYD13A2v4 MODIS product through the LP DAAC Data Pool
Via Search Tool: http://e0dps01u.ecs.nasa.gov:22000/OPS/drill?attrib=esdt&esdt;=MYD13A2.4&group;=MOLA
Via FTP Directory: ftp://e0dps01u.ecs.nasa.gov/MOLA/MYD13A2.004/
Order Data through the EOS Data Gateway
( http://edcimswww.cr.usgs.gov/pub/imswelcome/)
EOS Data Gateway Search Tips
Source: |
Aqua |
Sensor: |
MODIS |
Dataset: |
MODIS/Aqua Vegetation Indices 16-Day L3 Global 1km SIN Grid |
Spatial: |
HORIZONTALTILENUMBER Max/Min VERTICALTILENUMBER Max/Min |
Geographic Extent: |
Type Lat/Long Range or Draw on Map |
Temporal Extent: |
2003-03-06 to 2004-02-01 (V003); 2002-07-04 to present (V004) |
Product Information
Contact Information
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