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Full catalog/MYD09Q1
MYD09Q1·v006·dataset

True surface color, red and near-infrared (Aqua, 250 m, 8-day)

MODIS/Aqua Surface Reflectance 8-Day L3 Global 250m SIN Grid V006
land NASA LPCLOUD Level 3 HDF-EOS2
In plain English

What it measures. What the land surface actually looks like in two channels of light — red and near-infrared — after removing the haze, gases, and scattering the atmosphere adds, at a fairly fine 250-meter scale.

How it's made. Pieced together from eight days of MODIS observations off the Aqua satellite, picking the clearest, least-cloudy reading for each spot to make one composite image.

How & where you'd use it. A foundation for tracking vegetation, land cover, and how green or bare the ground is; note this version was retired in 2023 in favor of an updated release.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCE

Coverage & cadence

  • Time span2002-07-04 → 2023-02-26
  • Measured byAqua (MODIS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • StatusDEPRECATED

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 MYD09Q1 Version 6 data product was decommissioned on July 31, 2023. Users are encouraged to use the [MYD09Q1 Version 6.1](https://doi.org/10.5067/MODIS/MYD09Q1.061) data product. The MYD09Q1 Version 6 product provides an estimate of the surface spectral reflectance of Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) Bands 1 and 2, corrected for atmospheric conditions such as gasses, aerosols, and Rayleigh scattering. Provided along with the 250 meter (m) surface reflectance bands are two quality layers. For each pixel, a value is selected from all the acquisitions within the 8-day composite period. The criteria for the pixel choice include cloud and solar zenith. When several acquisitions meet the criteria the pixel with the minimum channel 3 (blue) value is used. Known Issues * The Collection 6 MODIS Land Surface Reflectance product (MYD09) may [incorrectly flag retrievals as ‘High Aerosol’](https://landweb.modaps.eosdis.nasa.gov/displayissue?id=174) over brighter surfaces and at higher view angles. This will impact the downstream MODIS BRDF/Albedo (MCD43) and Vegetation Index (MOD13 and MYD13) data products which use the aerosol quantity flag to screen out high aerosol values. * [Corrections](https://landweb.modaps.eosdis.nasa.gov/data/userguide/LSRHighAerosolFlagFinal.pdf) were implemented in Collection 6.1 reprocessing. * 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=Aqua&as=6).

Get the data

myd09q1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MYD09Q1",
    version="006",
    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.