The image above is a global monthly composite of the MODIS Normalized Difference Vegetation Index (NDVI) included in the MOD13C2 product. The NDVI values have been pseudo-colored to represent biomass health across the globe using data acquired in January 2001.
Global MODIS vegetation indices are designed to provide consistent spatial and temporal comparisons of vegetation conditions. Blue, red, and near-infrared reflectances, centered at 470-nanometers, 648-nanometers, and 848-nanometers, respectively, are used to determine the MODIS daily vegetation indices.
The MODIS Normalized Difference Vegetation Index (NDVI) complements NOAA's Advanced Very High Resolution Radiometer (AVHRR) NDVI products and provides continuity for historical applications. The MODIS NDVI product contains atmospherically corrected bi-directional surface reflectances masked for water, clouds, and cloud shadows. Another MODIS index, the Enhanced Vegetation Index or EVI, uses the blue band to remove residual atmospheric contamination caused by smoke and sub-pixel thin clouds. The EVI also uses feedback adjustment to minimize canopy background variations and to enhance vegetation sensitivity from sparse to dense vegetation conditions.
Global MOD13C2 data are cloud-free spatial composites of the gridded 16-day 1-kilometer MOD13A2, and are provided monthly as a level-3 product projected on a 0.05 degree (5600-meter) geographic Climate Modeling Grid (CMG). Cloud-free global coverage is achieved by replacing clouds with the historical MODIS time series climatology record.
Vegetation indices are used for globally monitoring vegetation conditions and are used in products displaying land cover and land cover changes. These data may be used as input for modeling global biogeochemical and hydrologic processes and global and regional climate. These data also may be used for characterizing land surface biophysical properties, including land cover.
Version-5 MODIS/Terra Vegetation Indices products are Validated Stage 2, meaning that accuracy has been assessed over a widely distributed set of locations and time periods via several ground-truth and validation efforts. Although there may be later improved versions, these data are ready for use in scientific publications.
Temporal Coverage | February 18, 2000 - |
Area | Global |
File Size | ~19 MB |
Projection | Lat/Lon |
Data Format | HDF-EOS |
Dimensions | 3600 x 7200 rows/columns |
Resolution | 0.05 degree (5600-meter) |
Science Data Sets (SDS HDF Layers) | 13 |
Science Data Sets for MODIS Terra Vegetation Indices Monthly L3 Global 0.05Deg CMG V005 (MOD13C2):
Science Data Sets (HDF Layers) (13) |
UNITS |
BIT TYPE |
FILL |
VALID RANGE |
MULTIPLY BY SCALE FACTOR |
---|---|---|---|---|---|
CMG 0.05 Deg Monthly NDVI | NDVI | 16-bit signed integer | -3000 | -2000, 10000 | 0.0001 |
CMG 0.05 Deg Monthly EVI | EVI | 16-bit signed integer | -3000 | -2000, 10000 | 0.0001 |
CMG 0.05 Deg Monthly VI Quality | Bit Field | 16-bit unsigned integer | 65535 | 0, 65534 | NA |
CMG 0.05 Deg Monthly red reflectance (Band 1) | Reflectance | 16-bit signed integer | -1000 | 0, 10000 | 0.0001 |
CMG 0.05 Deg Monthly NIR reflectance (Band 2) | Reflectance | 16-bit signed integer | -1000 | 0, 10000 | 0.0001 |
CMG 0.05 Deg Monthly blue reflectance (Band 3) | Reflectance | 16-bit signed integer | -1000 | 0, 10000 | 0.0001 |
CMG 0.05 Deg Monthly MIR reflectance (Band 7) | Reflectance | 16-bit signed integer | -1000 | 0, 10000 | 0.0001 |
CMG 0.05 Deg Monthly Avg sun zenith angle | Degree | 16-bit signed integer | -10000 | -9000, 9000 | 0.01 |
CMG 0.05 Deg Monthly NDVI std dev | NDVI | 16-bit signed integer | -3000 | -2000–10000 | 0.0001 |
CMG 0.05 Deg Monthly EVI std dev | EVI | 16-bit signed integer | -3000 | -2000–10000 | 0.0001 |
CMG 0.05 Deg Monthly #1km pix used | Pixels | 8-bit unsigned integer | 255 | 0–36 | 1.0 |
CMG 0.05 Deg Monthly #1km pix +-30deg VZ | Pixels | 8-bit unsigned integer | 255 | 0–36 | 1.0 |
CMG 0.05 Deg Monthly pixel reliability | Rank | 8-bit signed integer | -1 | 0–4 | 1.0 |
The QA information below is excerpted from the Quality Science Data Set within an HDF-EOS MOD13C2 file.
TABLE 1: MOD13C2 Pixel Reliability
A summary Quality layer has been included in the MOD13C2: “pixel reliability.” This layer contains ranked values describing overall pixel quality (Table 1 below).
Rank Key | Summary QA | Description |
-1 | Fill/No Data | Not Processed |
0 | Good Data | Use with confidence |
1 | Marginal data | Useful, but look at other QA information |
2 | Snow/Ice | Target covered with snow/ice |
3 | Cloudy | Target not visible, covered with cloud |
4 | Estimated | From MODIS historic time series |
TABLE 2: MOD13C2 VI Quality
Bit 0 is the least significant (read bit words right to left)
bit |
Long Name |
Value |
Key |
---|---|---|---|
0–1 | MODLAND_QA | 00 | VI produced, good quality |
01 | VI produced, but check other QA | ||
10 | Pixel produced, but most probably cloudy | ||
11 | Pixel not produced due to other reasons than clouds | ||
2–5 | VI usefulness | 0000 | Highest quality |
0001 | Lower quality | ||
0010 | Decreasing quality | ||
0100 | Decreasing quality | ||
1000 | Decreasing quality | ||
1001 | Decreasing quality | ||
1010 | Decreasing quality | ||
1100 | Lowest quality | ||
1101 | Quality so low that it is not useful | ||
1110 | L1B data faulty | ||
1111 | Not useful for any other reason/not processed | ||
6–7 | Aerosol quantity | 00 | Climatology |
01 | Low | ||
10 | Average | ||
11 | High | ||
8 | Adjacent cloud detected | 1 | Yes |
0 | No | ||
9 | Atmosphere BRDF correction performed | 1 | Yes |
0 | No | ||
10 | Mixed Clouds | 1 | Yes |
0 | No | ||
11–13 | Land/Water Flag | 000 | Shallow ocean |
001 | Land (Nothing else but land) | ||
010 | Ocean coastlines and lake shorelines | ||
011 | Shallow inland water | ||
100 | Ephemeral water | ||
101 | Deep inland water | ||
110 | Moderate or continental ocean | ||
111 | Deep ocean | ||
14–15 | Geospatial quality | 00 | <= 25% of the finer 1km resolution contributed to this CMG pixel |
01 | >25% and <= 50% of the finer 1km resolution contributed to this CMG pixel | ||
10 | >50% and <= 75% of the finer 1km resolution contributed to this CMG pixel | ||
11 | >75% and <=100% of the finer 1km resolution contributed to this CMG pixel |
Please find the current MODIS-related Data Redistribution and Pricing policies on the MODIS Policies Section of this Web Site
LP DAAC Acknowledgement and Citations Policy
In the event that data distributed from the Land Processes DAAC are incorporated into your research, please supply the following acknowledgment within your published work: "These data are distributed by the Land Processes Distributed Active Archive Center (LP DAAC), located at the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center (lpdaac.usgs.gov)." If possible, please e-mail or send us reprints/citations of papers or oral presentations based on data obtained from the LP DAAC (see below for mailing address and e-mail address). This will help us to stay informed of how the data are being utilized.
LP DAAC User Services
U.S. Geological Survey (USGS)
Earth Resources Observation and Science (EROS) Center
47914 252nd Street
Sioux Falls, SD 57198-0001
The complete data record for this product is available through the WIST search and order interface. A near-complete record is available on-line through the Data Pool.
Please find links to (and information about) these data access tools on the Get Data Section of this Web Site.
U.S. Geological Survey (USGS)
Center for Earth Resources Observation and Science (EROS)
47914 252nd Street
Sioux Falls, SD 57198-0001
Phone Number: | 605-594-6116 |
Toll Free: | 866-573-3222 |
866-LPE-DAAC | |
Fax: | 605-594-6963 |
Email: | lpdaac@eos.nasa.gov |
Web: | http://lpdaac.usgs.gov |