N: 90 S: -90 E: 180 W: -180
Description
The Terra Moderate Resolution Imaging Spectroradiometer (MODIS) Vegetation Indices 16-Day (MOD13C1) Version 6.1 product provides a Vegetation Index (VI) value at a per pixel basis. There are two primary vegetation layers. The first is the Normalized Difference Vegetation Index (NDVI) which is referred to as the continuity index to the existing National Oceanic and Atmospheric Administration-Advanced Very High Resolution Radiometer (NOAA-AVHRR) derived NDVI. The second vegetation layer is the Enhanced Vegetation Index (EVI), which has improved sensitivity over high biomass regions.
The Climate Modeling Grid (CMG) consists 3,600 rows and 7,200 columns of 5,600 meter (m) pixels. Global MOD13C1 data are cloud-free spatial composites of the gridded 16-day 1 kilometer MOD13A2 data, and are provided as a Level 3 product projected on a 0.05 degree (5,600 m) geographic CMG. The MOD13C1 has data fields for NDVI, EVI, VI QA, reflectance data, angular information, and spatial statistics such as mean, standard deviation, and number of used input pixels at the 0.05 degree CMG resolution.
Known Issues
- For complete information about known issues please refer to the MODIS/VIIRS Land Quality Assessment website.
Improvements/Changes from Previous Versions
- The Version 6.1 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: changes to the response-versus-scan angle (RVS) approach that affects reflectance bands for Aqua and Terra MODIS, corrections to adjust for the optical crosstalk in Terra MODIS infrared (IR) bands, and corrections to the Terra MODIS forward look-up table (LUT) update for the period 2012 - 2017.
- A polarization correction has been applied to the L1B Reflective Solar Bands (RSB).
Product Summary
Citation
Citation is critically important for dataset documentation and discovery. This dataset is openly shared, without restriction, in accordance with the EOSDIS Data Use and Citation Guidance.
Copy Citation
File Naming Convention
The file name begins with the Product Short Name (MOD13C1) followed by the Julian Date of Acquisition formatted as AYYYYDDD (A2025193), the Version of the data collection (061), the Julian Date and Time of Production designated as YYYYDDDHHMMSS (2025212174201), and the Data Format (hdf).
Documents
USER'S GUIDE
ALGORITHM THEORETICAL BASIS DOCUMENT (ATBD)
PRODUCT QUALITY ASSESSMENT
SCIENCE DATA PRODUCT VALIDATION
Variables
Variables are a set of physical properties whose values determine the characteristics or behavior of something. For example, temperature and pressure are variables of the atmosphere. Parameters and variables can be used interchangeably. Variable level attributes provide individual information for each variable.
The Name in this table is the variable name. Fill value indicates missing or undefined data points in a variable. Valid range is the range of values the variable can store. Scale factor is used to increase or decrease the size of an object and can be used to correct for distortion. For questions on a specific variable, please use the Earthdata Forum.
| Name Sort descending | Description | Units | Data Type | Fill Value | Valid Range | Scale Factor |
|---|---|---|---|---|---|---|
| CMG 0.05 Deg 16 days #1km pix +-30deg VZ | Number of 1km pixels used with VZ angle less than + or - 30 degs | Number | uint8 | 255 | 0 to 36 | N/A |
| CMG 0.05 Deg 16 days Avg sun zen angle | View zenith angle of VI Pixel | Degree | int16 | -10000 | -9000 to 9000 | 0.01 |
| CMG 0.05 Deg 16 days blue reflectance | Surface Reflectance Band 3 | N/A | int16 | -1000 | 0 to 10000 | 0.0001 |
| CMG 0.05 Deg 16 days EVI | 16 day EVI | EVI | int16 | -3000 | -2000 to 10000 | 0.0001 |
| CMG 0.05 Deg 16 days EVI std dev | Standard deviation computed from input EVI pixels | EVI | int16 | -3000 | 0 to 10000 | 0.0001 |
| CMG 0.05 Deg 16 days MIR reflectance | Surface Reflectance Band 7 | N/A | int16 | -1000 | 0 to 10000 | 0.0001 |
| CMG 0.05 Deg 16 days NDVI | 16 day NDVI | NDVI | int16 | -3000 | -2000 to 10000 | 0.0001 |
| CMG 0.05 Deg 16 days NDVI std dev | Standard deviation computed from input NDVI pixels | NDVI | int16 | -3000 | 0 to 10000 | 0.0001 |
| CMG 0.05 Deg 16 days NIR reflectance | Surface Reflectance Band 2 | N/A | int16 | -1000 | 0 to 10000 | 0.0001 |
| CMG 0.05 Deg 16 days number of 1km pix used | Number of 1 km input pixels used | Number | uint8 | 255 | 0 to 36 | N/A |
| CMG 0.05 Deg 16 days pixel reliabilty | Quality reliability of VI pixel | Rank | int8 | -1 | 0 to 4 | N/A |
| CMG 0.05 Deg 16 days red reflectance | Surface Reflectance Band 1 | N/A | int16 | -1000 | 0 to 10000 | 0.0001 |
| CMG 0.05 Deg 16 days VI Quality | VI quality indicators | Bit Field | uint16 | 65535 | 0 to 65534 | N/A |