These data are a copy of MODIS data from the NASA Level-1 and Atmosphere Archive & Distribution System (LAADS) Distributed Active Archive Center (DAAC). The copy is potentially only a subset. Below is the description from https://ladsweb.modaps.eosdis.nasa.gov/missions-and-measurements/products/MCD19A2

MCD19A2 is the shortname for the Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm-based Level-2 gridded (L2G) aerosol optical thickness over land surfaces product. Derived using both Terra and Aqua MODIS inputs, this L2 product is produced daily at 1 km pixel resolution. This product helps generate a number of atmospheric and geometric properties/parameters that are used to produce another facet of the MAIAC algorithm: the land surface Bidirectional Reflectance Factor.

The MCD19A2 product contains two data groups with the following Science Data Set parameters:

Grid500m groupAerosol Optical Depth at 047 micronAerosol Optical Depth at 055 micronAOD Uncertainty at 047 micronFine-Mode Fraction for OceanColumn Water Vapor in cm liquid waterAOD QAAOD Model (Regional background model used)Injection Height (Smoke injection height over local surface height)Grid5km groupCosine of Solar Zenith AngleCosine of View Zenith AngleRelative Azimuth AngleScattering AngleGlint Angle

The MCD19A2 product has achieved Stage-3 validation.

Shortname: MCD19A2 , Platform: Combined Aqua Terra , Instrument: MODIS , Processing Level: Level-2 Tiled , Spatial Resolution: 1 km , Temporal Resolution: daily , ArchiveSets: 6 , Collection: MODIS Collection 6 (ArchiveSet 6) , PGE Number: PGE113 , File Naming Convention: MCD19A2.AYYYYDDD.hHHvVV.CCC.YYYYDDDHHMMSS.hdf YYYYDDD = Year and Day of Year of acquisition hHH = Horizontal tile number (0-35) vVV = Vertical tile number (0-17) CCC = Collection number YYYYDDDHHMMSS = Production Date and Time , Citation: Alexi Lyapustin - NASA GSFC, Yujie Wang - Univeristy of Maryland Baltimore County and MODAPS SIPS - NASA. (2015). MCD19A2 MODIS/Terra+Aqua Aerosol Optical Thickness Daily L2G Global 1km SIN Grid. NASA LP DAAC. http://doi.org/10.5067/MODIS/MCD19A2.006 , Keywords: Atmospheric Correction, MODIS, MAIAC, Bidirectional Surface reflectance, Aerosols