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Full catalog/MOD09A1
MOD09A1·v006·dataset

True surface color (Terra, 8-day, 500 m)

MODIS/Terra Surface Reflectance 8-Day L3 Global 500m SIN Grid V006
land NASA LPCLOUD Level 3 HDF-EOS2
In plain English

What it measures. The true color of the land surface in seven color bands at 500-meter detail, corrected for atmospheric haze and scattering, picking the single best (least cloudy) view from each 8-day window. (This older version was retired in July 2023 for a newer one.)

How it's made. Compiled from the MODIS instrument on Terra by gathering 8 days of observations and choosing the clearest pixel for each spot, then mapping it onto a global grid.

How & where you'd use it. The cloud-screened 8-day compositing makes it a clean foundation for tracking seasonal vegetation and surface changes, and it feeds many downstream MODIS land products.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCE

Coverage & cadence

  • Time span2000-02-24 → 2023-02-17
  • Measured byTerra (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 MOD09A1 Version 6 data product was decommissioned on July 31, 2023. Users are encouraged to use the [MOD09A1 Version 6.1](https://doi.org/10.5067/MODIS/MOD09A1.061) data product. The Moderate Resolution Imaging Spectroradiometer (MODIS) Terra MOD09A1 Version 6 product provides an estimate of the surface spectral reflectance of Terra MODIS Bands 1 through 7 corrected for atmospheric conditions such as gasses, aerosols, and Rayleigh scattering. Along with the seven 500 meter (m) reflectance bands are two quality layers and four observation bands. 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 * Striping due to a dead detector is noticeable for bands 5, 6, and 7 in scenes acquired February 24 through October 31, 2000. Corrections were implemented to reduce the striping in data acquired after November 1, 2000. Users should always check the band quality for dead detectors even though reflectance values may be in the valid range. * The Collection 6 MODIS Land Surface Reflectance product (MOD09) may [incorrectly flag retrievals as ‘High Aerosol’](https://landweb.modaps.eosdis.nasa.gov/displayissue?id=86) 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=Terra&as=6).

Get the data

mod09a1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MOD09A1",
    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.