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Full catalog/MCD19A2CMG
MCD19A2CMG·v061·dataset

Haze, dust and water vapor in the air (Terra+Aqua, daily)

MODIS/Terra+Aqua AOD and Water Vapor from MAIAC, Daily L3 Global 0.05Deg CMG V061
land NASA LPCLOUD Level 3 active HDF-EOS2
In plain English

What it measures. Provides daily worldwide maps of two things in the air: how hazy the sky is from particles like dust and smoke (aerosol optical depth at a few light colors), and how much water vapor is in the air column. It also includes uncertainty estimates, cloud cover, and viewing details.

How it's made. Produced from MODIS instruments on the Terra and Aqua satellites using the MAIAC processing method, gridded daily to about 5.6 km cells.

How & where you'd use it. Used to monitor air quality and haze, study dust and smoke, and as the atmospheric correction information needed to make accurate land surface reflectance maps.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCE

Coverage & cadence

  • Time span2000-02-24 → ongoing
  • Measured byTerra (MODIS) · Aqua (MODIS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The MCD19A2CMG 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) and Water Vapor Level 3 product produced daily in a 0.05 degree (5,600 meters at the equator) Climate Modeling Grid (CMG). The MCD19A2CMG product provides the atmospheric properties and view geometry used to calculate the MAIAC Surface Reflectance data products ([MCD19A1CMGL](https://doi.org/10.5067/MODIS/MCD19A1CMGL.061) and [MCD19A1CMGO](https://doi.org/10.5067/MODIS/MCD19A1CMGO.061)). The MCD19A2CMG 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, column water vapor for Terra, column water vapor for Aqua, average cloud fraction, available AOD, satellite overpass times, line and sample number, offset, and number of AOD records. 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. Known Issues * Known issues are described in Section 6 of the User Guide. * For complete information about known issues please refer to the [MODIS/VIIRS Land Quality Assessment website](https://landweb.modaps.eosdis.nasa.gov/knownissue?sensor=MODIS&sat=TerraAqua&as=61).

Get the data

mcd19a2cmg_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MCD19A2CMG",
    version="061",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from LPCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.