Description
The Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) Vegetation Indices (MYD13A3) Version 6.1 data are provided monthly at 1 kilometer (km) spatial resolution as a gridded Level 3 product in the sinusoidal projection. In generating this monthly product, the algorithm ingests all the MYD13A2 (https://doi.org/10.5067/MODIS/MYD13A2.061) products that overlap the month and employs a weighted temporal average.
The MODIS Normalized Difference Vegetation Index (NDVI) complements NOAA's Advanced Very High Resolution Radiometer (AVHRR) NDVI products and provides continuity for time series historical applications. MODIS also includes an Enhanced Vegetation Index (EVI) that minimizes canopy background variations and maintains sensitivity over dense vegetation conditions. The EVI uses the blue band to remove residual atmosphere contamination caused by smoke and sub-pixel thin clouds. The MODIS NDVI and EVI products are computed from surface reflectances corrected for molecular scattering, ozone absorption, and aerosols.
Vegetation indices are used for global monitoring of 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 as well as global and regional climate. Additional applications include characterizing land surface biophysical properties and processes, such as primary production and land cover conversion.
Provided along with the vegetation layers and the two quality assurance (QA) layers are reflectance bands 1 (red), 2 (near-infrared), 3 (blue), and 7 (mid-infrared), as well as three observation layers.
Validation at stage 3 (https://modis-land.gsfc.nasa.gov/MODLAND_val.html) has been achieved for the MODIS Vegetation Index product suite. Further details regarding MODIS land product validation for the MOD13 data products are available from the MODIS Land Team Validation site (https://modis-land.gsfc.nasa.gov/ValStatus.php?ProductID=MOD13).
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).
Resources
| Name | Format | Description | Link |
|---|---|---|---|
| Download this dataset through APPEEARS | HTML | The Application for Extracting and Exploring Analysis Ready Samples (AρρEEARS) offers a simple and efficient way to perform data access and transformation processes. | Open resource |
| Get a related visualization | HTML | Browse image for Earthdata Search. | Open resource |
| This dataset's landing page | HTML | The LP DAAC product page provides information on Science Data Set layers and links for user guides, ATBDs, data access, tools, customer support, etc. | Open resource |
| Download this dataset | HDF | LP DAAC Data Pool provides direct access to available products via HTTPS. | Open resource |
| View documentation related to this dataset | HTML | The File Specification provides a description of the product file including Scientific Data Sets and their attributes. | Open resource |
| View this dataset's product quality assessment | HTML | Quality Assessment provides information regarding the usability and usefulness of the data product. | Open resource |
| The dataset's project home page | HTML | The LP DAAC website provides detailed information on discovery, distribution, access, and support of land data products. | Open resource |
| View this dataset's algorithm theoretical basis document | The Algorithm Theoretical Basis Document (ATBD) describes the physical and mathematical algorithms for the product. | Open resource | |
| View this dataset's user's guide | The technical information in the User's Guide enables users to interpret and use the data products. | Open resource | |
| View this dataset's science data product validation documentation | HTML | Validation at stage 3 has been achieved for the MODIS Vegetation Index product suite. | Open resource |
| View this dataset's science data product validation documentation | HTML | Further details regarding MODIS land product validation for the MYD13 data products are available from the MODIS Land Team Validation site. | Open resource |
| Use OPeNDAP to access the dataset's data | HTML | Access data via Open-source Project for a Network Data Access Protocol. | Open resource |
| Google Scholar search results | HTML | Search results for publications that cite this dataset by its DOI. | Open resource |
| Download this dataset through Earthdata Search | HDF | Earthdata Search allows users to search, discover, visualize, refine, and access NASA Earth Observation data. | Open resource |