Description
The MCD19A2 Version 6.1 data product is a Moderate Resolution Imaging Spectroradiometer (MODIS) Terra and Aqua combined Multi-angle Implementation of Atmospheric Correction (MAIAC) Land Aerosol Optical Depth (AOD) gridded Level 2 product produced daily at 1 kilometer (km) pixel resolution. The MCD19A2 product provides the atmospheric properties and view geometry used to calculate the MAIAC Land Surface Bidirectional Reflectance Factor (BRF) or surface reflectance, MCD19A1 product.
The MCD19A2 AOD data product contains the following Science Dataset (SDS) layers: blue band AOD at 0.47 µm, green band AOD at 0.55 µm, AOD uncertainty, fine mode fraction over water, column water vapor over land and clouds (in cm), smoke injection height (m above ground), AOD QA, AOD model at 1km, cosine of solar zenith angle, cosine of view zenith angle, relative azimuth angle, scattering angle, and glint angle at 5km. A low-resolution browse image is also included showing AOD of the blue band at 0.47 µm created using a composite of all available orbits.
Each SDS layer within each MCD19A2 Hierarchical Data Format 4 (HDF4) file contains a third dimension that represents the number of orbit overpasses. This factor could affect the total number of bands for each SDS layer.
Validation at stage 1 (https://landweb.modaps.eosdis.nasa.gov/cgi-bin/QA_WWW/newPage.cgi?fileName=maturity) has been achieved for the AOD SDS layers. Further details regarding MODIS land product validation for MCD19 data products are available from the MODIS Land Team Validation site (https://modis-land.gsfc.nasa.gov/ValStatus.php?ProductID=MOD19).
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).
* The MCD19 Version 6.1 products have added 250 m resolution bands.
* The previous BRDF product (MCD19A3) was reported once every eight days and the new MCD19A3D is a daily product.
* MCD19A3D introduces gap-filled NDVI and gap-filled 250 m NBAR.
* Snow Fraction, Snow Fit, and Snow Grain size layers were moved from MCD19A1 to the MCD19A3D.
* There are four additional Climate Modeling Grid (CMG) products: MCD19A1CMGL, MCD19A1GO, MCD19A2CMG, and MCD19A3CMG.
Resources
| Name | Format | Description | Link |
|---|---|---|---|
| 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 1 has been achieved for the MODIS MAIAC products. | Open resource |
| View this dataset's science data product validation documentation | HTML | Further details regarding MODIS land product validation for the MCD19 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 |